We consider the motion of a Brownian particle trapped in an arbitrary bounded two or three-dimensional domain, whose boundary is reflecting except for a small absorbing window through which the particle can escape. We use the method of matched asymptotic expansions to calculate the mean first passage time, defined as the time taken for the Brownian particle to escape from the domain through the absorbing window. This is known as the narrow escape problem. Since the mean escape time diverges as the window shrinks, the calculation is a singular perturbation problem. We extend our results to include N absorbing windows of varying length in two dimensions and varying radius in three dimensions. We present findings in two dimensions for the unit disk, unit square and ellipse and in three dimensions for the unit sphere. The narrow escape problem has various applications in many fields including finance, biology, and statistical mechanics. / Science, Faculty of / Mathematics, Department of / Graduate

In the stochastic modeling of neurons, the first passage time problem arises as a natural object of study when considering the inter spike interval distribution. In this report, we study some aspects of this problem as it arises in the context of neuroscience. In the first chapter we describe the basic neurophysiology required to model the neuron. In the second, we study the Poisson model, Stein’s model, and some diffusion models, calculating or indicating methods to compute the density of the first passage time random variable or its moments. In the third and fourth chapters, we study the Fokker-Planck equation, and use it to compute the first passage time in the discrete and continuous time random walk cases. In the final chapter, we study sequences of neurons and the change in the density of the waiting time distributions, and hence in the inter spike intervals, as the output spike train from one neuron is considered as the input in the subsequent neuron.

En 2003, le comité permanent de la justice et des droits de la personne a été chargé d’étudier le projet de loi C-23, qui visait la mise en place d’un registre national des délinquants sexuels au Canada. Lors de ce processus, 12 mémoires ont été présentés au comité par des organismes et des individus qui désiraient se prononcer sur la controverse soulevée par ce projet de loi. Cette thèse vise deux objectifs inter-reliés : l’un empirique, l’autre théorique. Tout d’abord, il s’agit de mener une analyse des diverses problématisations que les auteurs de ces mémoires ont fait de la controverse. Dans un deuxième temps, cet analyse est aussi un exercice d’application théorique, où les concepts d’acteurs, d’actant et de point de passage obligé, qui sont proposés par la sociologie de l’acteur-réseau de Bruno Latour, sont utilisés.

This thesis solves estimation and control problems in computational neuroscience, mathematically dealing with the first-passage times of diffusion stochastic processes. We first derive estimation algorithms for model parameters from first-passage time observations, and then we derive algorithms for the control of first-passage times. Finally, we solve an optimal design problem which combines elements of the first two: we ask how to elicit first-passage times such as to facilitate model estimation based on said first-passage observations. The main mathematical tools used are the Fokker-Planck partial differential equation for evolution of probability densities, the Hamilton-Jacobi-Bellman equation of optimal control and the adjoint optimization principle from optimal control theory. The focus is on developing computational schemes for the solution of the problems. The schemes are implemented and are tested for a wide range of parameters.

Cette thèse a pour but d’analyser l’émergence et l’évolution de différents discours portant sur la sécurité et la souveraineté arctiques au Canada, pendant la décennie 2000-2010. Notre regard portera plus précisément sur le discours du Grand Nord assiégé. Une de nos questions de recherche fut de comprendre comment des évaluations optimistes et pessimistes du portrait sécuritaire arctique au Canada se sont traduites dans les discours sécuritaires arctiques tenus par différents acteurs politiques canadiens au cours de la décennie 2000-2010. De plus, une deuxième question de recherche se demandera si des groupes de la société civile canadienne ont été à même de formuler des idées sécuritaires alternatives à celles défendues par le gouvernement canadien. Pour ce faire, nous réaliserons une analyse de contenu qualitative de trois différents acteurs politiques canadiens : le gouvernement fédéral, les médias, plus particulièrement les textes d’opinion dans les quotidiens canadiens, et les groupes inuits. Une attention particulière sera portée à trois crises de souveraineté ayant éclaté durant cette période : la crise de l’île de Hans (été 2005), celle du sous-américain USS Charlotte (hiver 2005-2006) et la crise du drapeau russe sous le pôle nord (été 2007). Nos conclusions nous indiquent que le discours pessimiste a été exprimé en tout premier lieu dans les médias canadiens avant d’être inséré dans la rhétorique gouvernementale en 2005. De plus, les menaces étatiques vont davantage mobiliser les différents acteurs politiques canadiens étudiés que les menaces non-étatiques. La menace russe en particulier a été utilisée pour justifier des mesures additionnelles de défense de la souveraineté canadienne en Arctique. Sur notre deuxième question de recherche, nous pouvons observer que la société civile canadienne a été capable d’exprimer des idées sécuritaires alternatives. Par contre, les idées dominantes du continentalisme et du nationalisme ont guidé la politique étrangère canadienne pendant une bonne partie de la décennie, l’internationalisme libéral étant marginalisé par la prédominance de celles-ci. De plus, les groupes inuits ont été les plus à même de formuler des conceptualisations alternatives de la sécurité et de la souveraineté arctiques au Canada.

Les tests couramment utilisés pour évaluer le déficit sensori-moteur induit par une lésion du cerveau chez le rat posent problèmes en termes de sensibilité, d’objectivité et de quantification. Nous avons émis l'hypothèse selon laquelle l'analyse 3D de la cinématique de la locomotion constitue un paradigme expérimental approprié pour quantifier un tel déficit. Aussi, la locomotion a été étudiée lors d'une course sur tapis roulant (25 cm/s) muni ou pas d'obstacles (deux obstacles de 3cm de haut et 1,2 cm de large) à l'aide du système optoélectronique VICON. Le mouvement des quatre pattes a été simultanément enregistré avant et après induction d'une lésion unilatérale soit du striatum (mort d'origine métabolique des neurones striataux) soit du cortex cérébral (infarctus du cortex moteur) chez le rat adulte. Le laboratoire a précédemment montré que ces deux modèles de lésion conduisaient à une anomalie plus ou moins durable de la traversée d'une poutre étroite et surélevée, test classiquement utilisé pour évaluer la locomotion du rat. La première étude décrit pour la première fois la stratégie utilisée par le rat pour franchir un obstacle. Elle révèle que le franchissement s'accompagne d'une rupture complète du pattern locomoteur de base et que l'élévation des ceintures contribue de façon notable au passage de chacune des pattes au- dessus de l'obstacle. La seconde étude montre que la lésion du striatum s'accompagne d'un déficit locomoteur durable lors des deux modalités de course, l'anomalie portant sélectivement sur les pattes contralatérales à la lésion. Plus précisément, ces pattes présentent une flexion exagérée pendant la phase d'appui dont la durée est augmentée. Par ailleurs, lorsque que la patte antérieure opposée à la lésion conduit la manœuvre de franchissement, elle prend fréquemment appui sur l'obstacle suite à une initiation trop précoce de son élévation. Dans ce cas, la patte postérieure homolatérale franchit ou non correctement l'obstacle. L’ensemble de ces résultats suggère l’implication du striatum dans la programmation des mouvements guidés par la vue. La dernière expérience montre qu'aucune des modalités de locomotion n'est affectée par la lésion corticale, suggérant que le faisceau corticospinal n’est indispensable ni à la locomotion ni à son adaptation à l’environnement. En conclusion, notre travail montre que nos modalités d'enregistrement de la locomotion sont appropriées pour quantifier le déficit fonctionnel induit par une lésion du striatum, mais pas celui induit par une lésion du cortex moteur. Il serait intéressant de répéter les expériences lors d'une course volontaire, de manière à s'affranchir de la stimulation sensitive générée par le déroulement du tapis sous les pattes et d’étudier la réversibilité du déficit en cas de lésion partielle du striatum. / Although the rat has become the favourite animal model in preclinical researches on locomotion, studies designed to assess the strategy used by rats to avoid obstacle avoidance are lacking in rats. Using an optoelectronic 3D motion analysis system, we have, therefore, compared the step pattern, timing and length variables of locomotor cycles, trajectories and joint angles values of limbs when rats stepped between and overcame obstacles (3 cm-height) fixed on a treadmill belt (25 cm/s). Motion of all the four limbs was serially recorded for a 10 weeks long-period in adult animals with an initial age of 11 weeks. The results show that obstacle avoidance results in disruption of the basic step pattern thus resulting in increased stride length of all limbs, increased duration of the swing phase of forelimbs, only, and appearance of quadrupedal stance phases. They also reveal that elevation of limbs above the obstacle not only involved their flexion but also displacement of corresponding girdles. Remarkably, trajectory of the forelimb that was the second to overcome obstacle was the mirror image of that of the leading forelimb. Lastly, all measured parameters remain stable over the observation period during which body weight gain reaches 100 g (one third of the initial body weight). In conclusion, our study may represent a basic work for futures studies aimed at understanding the neural pathways involved in pathologies associated with deficit/recovery of challenged locomotion.

Orientador: Ana Angélica Medeiros Albano / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Educação / Made available in DSpace on 2018-08-27T13:17:54Z (GMT). No. of bitstreams: 1 Reyes_RoseHelena_D.pdf: 19938134 bytes, checksum: 11b97fdc7cd1bb24a5afd74a84626a53 (MD5) Previous issue date: 2014 / Resumo: A presente pesquisa consiste no relato de uma práxis pedagógica construída ao longo de 23 anos no âmbito do Ensino Fundamental, na Escola Casa Via Magia. É um relato da história de uma experiência de ritual de passagem com as crianças do quinto ano, último ano delas na nossa escola. Uma montagem de teatro que foi se tornando um drama ritual que busca favorecer as mudanças na vida dessas crianças nesse momento: crescer, mudar de nível escolar e de escola. Traz a memória dessa construção, uma reflexão sobre o tecer da metodologia e da cosmovisão desse trabalho de encenação, que inclui um diálogo entre os saberes, entre as artes e delas com as ciências, entre artistas educadores e as crianças, entre as crianças elas mesmas e de cada um consigo mesmo. Retoma certas referências do teatro contemporâneo e/ou experimental (Stanilavski, Artaud, Grotowski e Brook), da arte-educação de Read e da psicanálise (especialmente de Lacan e Freud, entre outros). Faz contato com a pesquisa antropológica de Lévi-Strauss, Van Gennep, Turner, DaMatta e outros, assim como contato com reflexões filosóficas, especialmente de Heidegger e dos estudiosos de sua obra. Em última instância trata-se de dar atenção aos encontros e despedidas de nossas vidas e do desvelamento do nosso ser, sempre ser-com. Um cuidado que a arte, a educação e a rede de afetos têm podido potencializar nessa experiência a ser compartilhada / Abstract: This research consists on the report of a pedagogical praxis built over 23 years within the framework of elementary teaching at Casa Via Magia Elementary School. It is a report of the history of a rite of passage experience with children of the fifth grade that are leaving the school. A theater production that became a ritual drama which aims to encourage changes in the lives of these children in this specific phase: growing, changing of school and educational level. It brings the memory of that construction, a reflection on the weaving of this methodology and the worldview of this staging work, which includes a dialogue between knowledges, arts, arts with sciences, between art educators and children, between the children themselves and each one with themselves. Reviewing certain references of contemporary and/or experimental theater (Stanilavski, Artaud, Grotowski and Brook), Read¿s art-education and psychoanalysis (especially Lacan and Freud, among others). Getting in touch with the anthropological researches of Lévi-Strauss, Van Gennep, Turner, Da Matta and others, as well as contacts with philosophical thoughts, especially Heidegger¿s and researchers on his work. Ultimately it is about giving attention to encounters and farewells of our lives and the unveiling of our being, always being-with. A well care that art, education and the network of affections have been able to enhance in this experience to be shared / Doutorado / Educação, Conhecimento, Linguagem e Arte / Doutora em Educação

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-01-25T13:11:53Z No. of bitstreams: 1 thiagorodriguestavares.pdf: 2612002 bytes, checksum: bf1572d41b9d33e10c19f9c5d6b42efe (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-01-25T19:32:37Z (GMT) No. of bitstreams: 1 thiagorodriguestavares.pdf: 2612002 bytes, checksum: bf1572d41b9d33e10c19f9c5d6b42efe (MD5) / Made available in DSpace on 2016-01-25T19:32:37Z (GMT). No. of bitstreams: 1 thiagorodriguestavares.pdf: 2612002 bytes, checksum: bf1572d41b9d33e10c19f9c5d6b42efe (MD5) Previous issue date: 2014-03-25 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Partindo da reflexão sobre a relação da sociedade com a sua religiosidade e a questão da finitude do Homem, esta dissertação aborda as atitudes dos vivos frente à morte. No catolicismo a morte é compreendida como uma passagem de um mundo para outro havendo obrigações entre vivos e mortos, esses últimos se encontrando em um momento de liminaridade. Cabe aos vivos a preparação do ritual de passagem que proporcione a transição tranquila do morto, sua alma deverá seguir em direção ao seu destino final, rumo a outra vida, outra margem. Empiricamente, tal questão será observada a partir da compreensão dos rituais funerários da cidade de Presidente Kubitschek no Vale do Jequitinhonha e da apreciação do Jubileu de São Miguel e Almas no Cemitério do Peixe, ambos em Minas Gerais. Assim, a partir de métodos etnográficos e da realização de entrevistas com base na metodologia de História oral, esta pesquisa busca esclarecer os rituais de passagem presentes numa vivência popular do catolicismo e as possíveis transformações nas atitudes dos Homens diante da morte – essas se referem às relações estabelecidas entre os vivos e destes com os mortos e as almas. Tal elo é constituído antes, durante e após os rituais fúnebres. Verificou-se que o momento da morte se destaca na vivência popular do catolicismo, no qual o rito coletivo tem extrema importância, pois é o elo entre familiares, vizinhos e amigos. Conclui-se que são nesses momentos em que todos estão juntos que fazem com que qualquer ritual coletivo seja um momento de sociabilidade, solidariedade e festa. / Starting from reflections about the relationship among society, it's religiosity and the finitude of men, this work intends to approach the attitudes of the living in face of death. In Catholicism death is understood as a passage from one world to another, establishing obligations between the living and the dead, the latter being in a moment of liminarity. It is the living's responsability to prepare a rite of passage which grants a tranquil transition of the dead; it's soul must, then, move towards it's final ending, towards another life, another border. Empirically, this matter will be observed from the observation of funerary rituals in the city of Presidente Kubitschek, in Vale do Jequitinhonha, and from the apreciation of Jubileu de São Miguel das Almas in the Cemitério do Peixe, both in Minas Gerias, Brazil. Thus, from the Ethnographic method, this research will clarify the existing rites of passage in the experience of popular Catholicism and the possible transformations in the attitudes of men towards death – these reffer to the relationships established among the living, and among them and the dead and the souls. Such link is constituted before, during and after the death rituals. It was verified that the moment of death outstands in the popular experience of Catholicism, where the collective rite has the uttermost importance, for it is the link among family, neighbours and friends. It is concluded that these precise moments, when everybody is together, are the ones that makes rite a moment of sociability, solidarity and festivity.

abstract: “Her Brown Body Is Glory: A Legacy of Healing Forged Through Sisterhood and Dance” fondly captures the process of creating the evening length dance project, Her Brown Body Is Glory (HBBIG). This document addresses many themes, such as liminality, rites of passage, trauma in the African American community (like the effects of Dr. Joy DeGruy Leary’s “Post Traumatic Slave Syndrome (PTSS) theory), and provides a perspective of healing rooted in dance, rituals, and community. This research focuses on dance being the source of intervention to create sisterhood among African American women of many shades. Throughout the creation of this dance project, the choreographer and dancers collaboratively generated experiences to cultivate a space of trust, vulnerability, sisterhood, and growth. The use of written, verbal, and movement reflection supported this creative process as the main source of ritual to check in with self, building community amongst the dancers, and generating choreography. The insertion of these sisterhood rituals into the production became the necessary element of witness for the audience to experience an authentic and moving performance of Her Brown Body Is Glory. / Dissertation/Thesis / Masters Thesis Dance 2020

The purpose of this thesis is to counterargue Simon Dalby’s claim that the national security perspective should be replaced by a global security perspective. Dalby argues that the national security is inappropriate to capture the current issues regarding the environmental security. To counterargue Dalby’s claim, I represent the national security perspective by using the perspective of states’ energy security, and compare current trends and issues regarding states’ energy security and the environmental security. This is done to argue that states can either chose to enhance their own energy security or the environmental security. Prisoners' Dilemma is then used as a theoretical framework on an explanatory example to provide insights about a dilemma, called the Energy- Environment Dilemma in this thesis, that curbs states’ ability to commit themselves to the cause of protecting the environmental security. The explanatory example used is the strategic importance of the Northwest passage for the U.S. and Canada. The results of this thesis suggests that the national security perspective, in combination with Prisoners’ Dilemma, is useful to provide insights about the Energy-Environmental Dilemma. Replacing it with a global security perspective would be to ignore a perspective which can provide insights about a challenge for states to commit to the cause of protecting the environmental security.