NCube/papyrus huggingface dataset:
Rôle des astrocytes dans la décharge rythmique neuronale du noyau sensoriel principal du trijumeau

Communication between neurons rests on their capacity to change their firing pattern to encode different messages. For several vital functions, such as respiration and mastication, neurons need to generate a repetitive firing pattern, and the groups of neurons responsible for these rhythmic discharges are called central pattern generator (CPG). Despite intense research in this field, the exact mechanisms underlying rhythmogenesis in CPGs are not completely defined. In most instances, the potential contribution of astrocytes is largely unexplored, even though these cells are now well known to be involved in neuronal synaptic modulation. In our work, the trigeminal main sensory nucleus (NVsnpr) was used as a model owing to its central role in the rhythmic movement of mastication. Previous work have shown that rhythmic bursting discharge is triggered in NVsnpr neurons when extracellular calcium concentration ([Ca2+]e) is artificially decreased. Based on this observation, our first hypothesis postulated that the reduction of [Ca2+]e could also happen physiologically in relation to relevant sensory stimulation. Secondly, because astrocytes have been involved in the buffering and the homeostasis of extracellular ions like potassium, we have postulated that these cells could also play a role in the control of [Ca2+]e. The results presented in this thesis show that astrocytes can regulate [Ca2+]e and thus control the ability of neurons to change their firing pattern. First, we showed that stimulation of sensory afferent fibers to the NVsnpr induced neuronal rhythmic bursting and in parallel reduction of [Ca2+]e . Secondly, we have demonstrated that astrocytes respond to the same sensory stimuli that induce neuronal rhythmic activity, and their blockade with a Ca2+ chelator prevents generation of neuronal rhythmic bursting. This ability is restored by adding S100β, an astrocytic Ca2+-binding protein, to the extracellular space, while the application of an anti- S100β antibody prevents generation of rhythmic activity. These results indicate that astrocytes regulate a fundamental neuronal property: that is the capacity to change their firing pattern. Thus, CPG functions result from integrated neuronal and glial activities. These findings may have broad implications for many other neural networks whose functions depend on the generation of rhythmic activity.

Keyphrases: Mastication, Calcium, Astrocyte, S100β, Trigeminal main sensory nucleus, Rhythmicity, Central pattern generator
Caractérisation physiologique et génétique des épilepsies d'origine focale chez l'humain et dans les modèles animaux

Epilepsy is a chronic neurological disease affecting approximately 3% of individuals at some time in their life. While seizures can generally be controlled with pharmacological treatments, there are 30% of epileptic patients that are not responding to any medication. These pharmaco-resistant epilepsies are associated with high morbidity and mortality resulting in massive human and societal costs. Sudden unexpected death in epilepsy (SUDEP) is responsible for up to 50% of death in pharmaco-resistant patients. The highest level of pharmaco-resistance is associated with focal epilepsies. Temporal lobe epilepsy (TLE), the most frequent focal epilepsy, is often associated with hippocampal sclerosis (HS), a pathology characterized by neuronal loss and gliosis. Initially considered as a symptomatic and acquired form of epilepsy, we now know that genetic factors play a major role in the development of TLE and HS. In this context, it is of great interest to study the molecular mechanisms underlying focal epilepsies and their associated pathologies in order to better understand the disease. The main goal of this thesis is to assess the genetic components of these epilepsies using two different approaches: the study of human genetic and experimentation using animal models.   Due to the advances of new sequencing technologies, several new genes have been associated with focal epilepsies. In the first chapter of this thesis, we assess the importance of mutations in the DEPDC5 gene in our French-Canadian cohort of focal epilepsy and familial focal epilepsy with variable foci. We discovered a new mutation as well as a recurrent mutation explaining 5% of our cases with focal epilepsy. The second chapter focus on genetic factors associated with hippocampal sclerosis in animal models of TLE. We demonstrated that the Galr1 gene plays an important role in the susceptibility to neuronal death in inbred strains of rats. The third part of this thesis aim at describing a new animal model of SUDEP, which is a common complication of pharmaco-resistant focal epilepsies. Indeed, SHR rats, an inbred strain of rats, dies suddenly following prolonged generalized tonico-clonic seizures.  We therefore show that genetic background plays an important role in the susceptibility to SUDEP. We suggest that a combination of cardiac and respiratory abnormalities is responsible for the death of the animal.  Our results allow a better understanding of the molecular mechanisms underlying focal epilepsies. Furthermore, using inbred strains of rats, we demonstrated the importance of genetic factors for the development of prolonged seizure-induced cell death and SUDEP. These new inbred animal models will eventually lead to the findings of new genes associated with the susceptibility to neuronal death as well as the risk of premature death in epileptic patients.

Keyphrases: Focal epilepsy, Temporal lobe epilepsy, Hippocampal sclerosis, Genetic, Animal models, SUDEP
El análisis de la actividad de enseñanza en el contexto real de trabajo : un dispositivo de formación pedagógica para docentes universitarios

Concerning the issue of the pedagogical training intended for university professors, I believe that it is necessary and relevant to contribute to the development of devices that allow university professors to broaden the understanding of their own actions, values, and intentions, integrating the notion of transformation and professional development from their authentic work contexts. Taking into account the above-mentioned, I raised as research question: How do  university professors build their work experience through the analysis of their teaching practices in an authentic working context, and how do they develop their pedagogical competences? To respond to this question, I have proposed a pedagogical device that allows the analysis of teaching practices on the university professor in their authentic working context, as a strategy to develop the pedagogical dimension concerning their the academic work. I pursue three specific objectives: I) to identify the organizing elements of the teaching practice of university professors; II) to understand the existing correlation between the prescribed teaching practice and the authentic teaching practice according to the way the actors themselves conceive it and develop it, and (III) to assess the contributions of a pedagogical device that assumes the analysis of teaching practices in the university context as an instrument of professional development. To better understand the phenomenon of study and to answer the question research, I rely on three statements: First, I conceive the analysis of activity (teaching practice) from an ergonomic approach, according to the French tradition; secondly, the notion of situated action is adopted as a perspective of analysis of the teaching practice, and, thirdly, the pedagogical training is conceived, within this research, as a historic process, situated and individual, of comprehension and understanding. I have adopted the perspective of collaborative research and the professional development, which enabled me to recognize the voice of the professors participating, as builders of their own learning process. The training device allowed me to analyze the teaching practices of university professors from their own conceptions, and frames of reference, taking into account the complexity and the emerging nature of authentic teaching practices as a perspective of pedagogical development. The process developed allowed professors collaborating to understand and transform their practice teaching from product based frameworks, where what "must" be done in class is delimitated toward more constructive frameworks that enrich educational actions due to the process of analysis of teaching practices, and due to proposals of change built as apprentices inside the pedagogical device.

Keyphrases: Pedagogical formation, university teaching, university teaching practices, real work, teaching as situated action
Les compétences informationnelles des futurs enseignants québécois sur le Web

While Québec’s students from elementary schools to university now mainly use the Web to find information for their studies. many have difficulties getting the information they need. Faced with this new reality, inservice and preservice teachers must give students the proper information literacy training, that is to learn how to search, evaluate and use information to meet their needs. This study aims to analyze if Québec’s preservice teachers have the information literacy competencies to meet their own needs and if they are adequately trained to teach information literacy. To achieve this goal, this research uses a conceptual framework developed around three complementary elements: the information literacy concept, the information seeking process, and information literacy teaching methods. To meet the specific research objectives that resulted from the synthesis of these elements, a mixed methodology combines data collected from a survey, interviews and observations conducted with 353 preservice teachers of a university in Québec. Results on reported and actual practices of the students’ information seeking process on the Web show, firstly, that a majority of them are novice information searchers, as they plan little or not at all their research on the Web, use basic search strategies, and scarcely diversify their research tools, with Google as their preferred tool by far. Secondly, results show that most preservice teachers evaluate the information they find on the Web according to several criteria, including information verifiability and potential use for teaching and learning. But while a majority of preservice teachers are able to synthesize the information found on the Web, only a minority cites correctly their sources. Thirdly, results indicate that preservice teachers perceive their initial training in information literacy as clearly insufficient, for it has been mainly received at the beginning of their program and in the form of workshops by the university’s librarians. Our results also show that while a majority of preservice teachers plan to teach how to evaluate information found on the Web using many criteria and educate them about plagiarism, they will put less emphasis on teaching how to search for information on the Web. We conclude our study by summarizing and analyzing our results in the light of the existing literature and offering recommandations to improve information literacy teacher training.

Keyphrases: information literacy, information searching, information evaluation, information use, teacher training
Aspectos determinantes en el desempeño profesoral universitario en posgrados : un estudio desde los factores propios

This research belongs to the field of Measurement and Evaluation and, more specifically, is related to the evaluation of professorial work. There is a lot of literature on this matter, where authors address the problem using a variety of angles, evaluative perspectives, methodologies, techniques and instruments. These studies are usually conducted at the undergraduate level, as the number of courses gives larger samples of participants, which allow making some generalizations and broadening the scope. On the other hand, in most cases, it seems that, as far as graduate studies are concerned, we often find extrapolations which ignore the objectives, differences and specificities.  The research we proposed was emerging from this concern about the evaluation of professorial work in the context of advanced studies – scenarios of a Masters’ degree in Engineering.  To this extent, it is a fundamental research that did not aim at implementing a professorial work evaluation system but, starting from specific factors, was seeking the key aspects that affect stakeholders perceptions (professors, students and director) regarding professors’ teaching performance. Accordingly, we tried to define specific factors as elements that are related to the Teaching & Learning process but are particularly relevant for graduates studies.  The study that has been conducted allowed us to take into consideration the stakeholders’ perceptions that may shed some light on the determinants of teaching quality in a Masters’ degree in Engineering, using quantitative and qualitative research techniques in order to identify and explain, within a mixed-method framework, the most important factors. From this point of view, the study aggregates factors that are important in the context such as institutional environment, theory vs practice balance in courses, professor’s experience as researcher or consultant, students’ characteristics as well as their previous experiences, tutoring, role of research.  These factors – that are connected to teaching support – become strategic whenever professors’ performance in Masters’ degree in Engineering is evaluated.  Among the findings, this research lead to the conclusion that even though they are part of a common educative process, professors, students and directors’ ideals with regard of teaching quality may be slightly different.  In this sense, aspects such as professors’ methodology and research experience are highly valued by the students, whereas professors underline the importance of their work as a peer, i.e. being recognized in the academic community as a reference in the discipline. In addition, the academic Director brings another perspective where the professors’ engagement in relation with the programme goals and objectives becomes crucial.

Keyphrases: Techniques quantitatives, Techniques qualitatives, Teacher assessment, Graduate engineering, Quantitative techniques, Qualitative techniques
Le féminisme dans les manuels d’histoire nationale : enquête auprès d’élèves québécois de quatrième secondaire

Several research in history education have focused on the low number of women found in textbooks. However, none has looked at the issues of gender in the historical understanding of students. This study proposes to address these questions through an exploratory case study conducted with grade 10 students of national history. We asked these teenagers about their conceptions of the history textbook and feminism; first by using a questionnaire (n = 595) and then with the help of individual interviews (n = 9). During these interviews, excerpts of textbooks offering divergent narratives on feminism were presented. This thesis describes and analyzes the use of the textbooks by students, their conceptions of feminist struggles in history, as well as their understanding of the role of women in historical accounts (agency). Students perceive the history textbook as true and neutral. They first and foremost use it to answer queries related to specific historical content. They are reluctant to question it, even when faced with conflicting accounts. They tend to lessen the differences found in the narratives so that it reflects their initial conceptions of the subject. A majority of student associate the feminist movement with the past and make little links with the present. Their knowledge of feminism is predominantly limited to the right to vote and a very few other events, all devoid of context. Gender stereotypes are evident in the responses of many teenagers as well as anti-feminism, to a lesser extent. However, the majority of students interviewed were able to identify some differences in terms of the agency of women found in textbooks. This leads us to believe that the development of historical thinking in a classroom context could lead students to think more critically about gender issues in history.  Keywords: textbooks; feminism; women’s history; gender ; national history; high school; agency; historical thinking. 

Keyphrases: textbooks, feminism, women’s history, gender, national history, high school, agency, historical thinking
Quantification de l’équilibre dynamique lors de différentes conditions de marche chez les personnes en santé et hémiparétiques

Balance problems associated with sensorimotor impairments in individuals with hemiparesis post-stroke are a risk factor for falls during locomotion. This thesis aimed to foster knowledge on balance ability in this post-stroke population during locomotor tasks compared to healthy individuals. The first objective was to quantify difficulty in maintaining dynamic (i.e. related to body displacements) and postural (i.e. related to segment alignment) balance among individuals post-stroke walking on a treadmill. The second objective was to better understand the relationship between balance and gait pattern changes associated with stroke-related deficits such as reduced gait speed and asymmetry, or those associated with certain rehabilitation interventions such as using a split-belt treadmill with asymmetrical belt speeds or adding a load on the ankle. The results showed that individuals post-stroke had less difficulty in maintaining balance than their healthy counterparts when they walked at a self-selected speed (study #1). However, at a similar speed, the stroke group experienced greater difficulty in maintaining balance than the healthy group (study #1). Assessment of how walking on a split-belt treadmill with both asymmetrical and symmetrical belt speeds affects gait pattern and balance showed that healthy older individuals had similar ability in adapting and de-adapting, as demonstrated by changes in ground reaction forces, compared to healthy young adults (study #2). However, balance among older individuals, as measured by the difference in ground reaction forces during the braking and propulsive phases, was more affected by asymmetrical belt speeds than young adults (study #2). In individuals post-stroke, a more symmetrical gait pattern did not alter difficulty in maintaining balance (study #3). However, balance was more affected during the stance phase of the leg on the slow belt when walking with asymmetrical belt speeds (study #3). Finally, adding a load on the ankle, placed on the non-paretic side then on the paretic side, when walking did not affect dynamic balance among individuals post-stroke, but it did improve their postural balance (study #4). In summary, these results suggest that individuals post-stroke reduce their gait speed in order to maintain their balance. Moreover, the split-belt treadmill protocol does affect their balance but not as a result of their gait pattern becoming more symmetrical. Finally, adding a load on the ankle remains a relevant approach to improve gait function, however, it is not recommended to train balance in individuals post-stroke. Lastly, adding a load on the ankle is not a recommended balance training method. Gait speed when assessing balance and gait training at speeds faster than a self-selected gait speed are important factors to consider during rehabilitation of individuals post-stroke.

Keyphrases: Balance, Gait speed, Locomotor asymmetry, Load, Hemiparesis, Rehabilitation
Reconciling transition paradigms : a cross-national analysis of democratization during the third wave

This thesis studies transitions from authoritarianism that lead to democracy. We ask: Which conditions are necessary for the instauration of a minimally democratic regime? Our answer to this question is that successful democratization hinges on the presence of essentially two factors: (1) pressure "from below" in the form of mass mobilization; and (2) willingness "from above" to carry out reforms, evidenced by a crisis of the authoritarian regime. On one hand, mass mobilization is an unmistakable indicator to rulers that liberalization is inevitable. It shakes up the internal unity of the ruling block and fulfils a crucial watchdog function throughout the transition process. On the other hand, reform is only possible if moderate forces embracing the idea of opening up the political space manage to grab "the reins of power" within the authoritarian regime. Both elements are thus key to understanding why and how countries democratize. To demonstrate our argument we examine twenty-five transition cases between 1973 and 2004 using multi-value qualitative comparative analysis (QCA) and supplement our results with three illustrative case studies of Tanzania, Togo and Indonesia. The central contribution of our thesis is to reconcile the two main theoretical debates in the democratization literature by showing the complementarity of theories on transitions "from above" and transitions "from below".

Keyphrases: transitions "from above", transitions "from below", transitions to democracy, authoritarian regime crisis, mass mobilization, minimal democracy
Effets de divers stimuli sur les caractéristiques des cardiomyocytes en culture dans le but de définir les conditions optimisées pour la fabrication de tissu cardiaque de remplacement

In 2015, there are still a large number of people who die due to diseases of uncontrolled heart rhythm or due to lack of availability of compatible donor organs. Tissue engineering aim to create, repair or improve the function by different techniques. Tissue engineering is a viable option to reduce the mortality associated with many heart conditions. The overall goal of my PhD research was to study the functional impact of different stimuli in cardiac environment (mechanical and electrical stimulation) on cardiac cell cultures. This, in order to define optimized culture conditions for the production of replacement tissue using tissue engineering. This thesis presents the stages of creation and development of a bioreactor; a system that permits the culture of cardiac cells by integrating various stimuli. The optimization of culture conditions by using the bioreactor was confirmed by cell culture experiments that focus on cell proliferation, cell organization, gene and protein expression as well as on spontaneous activity. In the first place, our results show that although mean frequency of spontaneous activity remained unaltered, incidence of reentrant activity was significantly higher in samples cultured on glass compared to PDMS substrates. Higher spatial and temporal instability of the spontaneous rate activation was found when cardiomyocytes were cultured on PDMS, and correlated with decreased connexin-43 (unsignificant) and a significant increased CaV3.1 and HCN2 mRNA levels. Compared to cultures on glass, cultures on PDMS were associated with the strongest response to isoproterenol (β-adrenergic) and acetylcholine (parasympathetic). Secondly, we present the design of our bioreactor with an emphasis on its characteristics and by putting in perspective the relevance of our approach to optimize culture conditions and to improve profitability culture experiences and production stages of replacement heart tissue. Finally, a new approach is proposed to evaluate the characteristics of the contractile cells in culture which allows to validate the functional impact of stimuli, evaluate the heterogeneity in the beating behavior of the cells and to detect localized abnormal activity that could favour arrhythmia.

Keyphrases: cellules pacemakers, substrat de culture, Tissue engineering, autonomous activity, pacemaker cells, electrical stimulation, mechanical stimulation, culture substrate, stiffness