Dissertations / Theses: 'Canada. Transports Canada'

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Cissé, Ismaëlh Ahmed. "Trafic aérien de passagers au Canada : une analyse exploratoire du modèle origine-destination de Transports Canada pour le marché intérieur." Master's thesis, Université Laval, 2013. http://hdl.handle.net/20.500.11794/25411.

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Le dynamisme du secteur aérien canadien amène Transports Canada à réviser régulièrement ses techniques de modélisation du trafic de passagers afin d’améliorer la performance prédictive de ses modèles. Ce travail explore différentes versions d’un modèle PODM (Passanger Origin-Destination Model) que Transports Canada utilise pour prévoir le trafic de passagers entre une origine et une destination à l’intérieur du Canada avec des données de panel (i.e. longitudinales et transversales). Deux formes paramétriques (log-linéaire et Box-Cox) sont estimées dans leurs versions empilées, avec des effets fixes/aléatoires et avec des coefficients individuels variables (fixes/aléatoires). Nous proposons également des estimations non paramétriques à noyaux pour explorer les non-linéarités qui caractérisent la relation entre le nombre de passagers par couple origine-destination et le prix du billet, le PIB des zones d’origine et de destination, la durée en voiture du trajet et la fréquence des vols. L’hypothèse d’empilement des données et les formes fonctionnelles postulées se révèlent statistiquement inadéquates. La prise en compte de l’hétérogénéité des trajets et des effets temporels par l’inclusion d’effets fixes/aléatoires dans les modèles paramétriques est également rejetée par nos tests. Les modèles à coefficients variables individuels et les estimations non paramétriques se révèlent les méthodes les plus pertinentes pour capturer l’hétérogénéité entre trajets, les chocs temporels ou les non-linéarités présentes dans les relations d’intérêt. Mots clés : Box-Cox, transport aérien, trafic de passagers, origine-destination, Transports Canada, non paramétrique, panels.

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Desjardins, Ludwig. "L’apprentissage d’une nouvelle territorialisation des grands projets routiers au ministère des transports du Québec : entre constructeur de routes et aménageur du territoire." Marne-la-vallée, ENPC, 2007. http://pastel.paristech.org/4047/01/Th%C3%A8se_LDesjardins_ENPC.pdf.

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La planification des infrastructures routières est marquée par une crise au plan de l’acceptabilité sociale. En quelques décennies, les grands projets routiers ont cessé de représenter des monuments du progrès, pour devenir des objets de débat. Dès les années 1970, le ministère des Transports du Québec (MTQ) faisait face à un contrecoup important de sa politique de développement des routes. Le morcellement des tissus urbains par les réseaux routiers a été fortement dénoncé et plusieurs projets ont connu de fortes oppositions de la société civile. Ces grands projets s’imposent encore aujourd’hui difficilement dans un contexte sociétal où la mise en rapport des différentes représentations véhiculées par les acteurs du territoire peine à mener à des consensus ou à des solutions intégrées. Parallèlement, l’institutionnalisation du débat public (notamment à travers le BAPE) et la mise en place d’un cadre juridique viennent encadrer davantage les projets. En mobilisant le concept d’apprentissage organisationnel, la présente thèse répond à une double interrogation. Elle cherche d’abord à comprendre comment se déploient les projets routiers du MTQ dans leurs rapports aux territoires et à leurs acteurs. Ensuite, elle tente de cerner comment évoluent les pratiques planificatrices de ce promoteur face aux contraintes actuelles de la territorialisation des projets. Le terrain d’étude est formé de l’analyse de quatre études de cas, tous des grands projets routiers planifiés par le MTQ, puis de la recension des grands changements organisationnels liés à la planification des projets routier. Par la confrontation du contenu des projets à chaque étape de leur planification, aux requêtes et représentations mobilisés par les acteurs, les effets du rapport au territoire sur la configuration des projets peuvent être constatés. Il ressort de la thèse que les controverses qui se déploient autour des grands projets routiers témoignent d’une nouvelle forme de territorialisation. Les projets se définissent beaucoup plus dans un enchevêtrement de rapports d’acteurs, que dans l’application de paramètres rationnels prédéfinis. Aux choix tranchants d’un acteur hégémonique se substitue une gouvernance des projets axée sur une imbrication et une pluralité d’acteurs. Les conduites de projet répondent d’un rapport au territoire plus complexe, qui vient remettre en question l’héritage technique et le rôle traditionnel conféré au MTQ. De manière transversale, la thèse fait ressortir une série d’apprentissages au sein des pratiques planificatrices du MTQ face à cette nouvelle territorialisation des projets routiers
The planning of large-scaled road projects is facing a crisis of public acceptability. During the last few decades, road projects have stopped being associated with progress, to become a subject of debate among western societies. Since the 1970s, the Quebec Ministry of Transportation (MTQ) has been, and is still facing major conflicts in the planning of road projects, especially in urban neighbourhoods. The impacts to urban fabric by new road networks have created strong oppositions. Therefore, these large-scale projects are more difficult to implement in a societal context where diverging stakeholder views make it difficult to attain consensus or integrated solutions. By using the concept of organizational learning, this thesis answers a double interrogation. It searches to understand how the implementation of road projects relates to stakeholders views and the environmental settings. Secondly, it seeks to understand how the planning practices are evolving from those experiences. The field of study is formed by four case studies of large road projects planned by the MTQ, and the inventory of organizational changes relating to planning practices. By confronting the projects characteristics with the stakeholders positioning, at each step of the procedure, we observed the effects of the public debate on the project design. Also, the analysis of the changes in the planning practices, from one project to another, enables us to identify the organizational learning abilities of the MTQ. Our results identify that the relationship between projects and the environment are much more complex that they were previously, as a new form of ‘territorialisation’ is manifesting itself. The comprehensive planning approach is leaving space for the debate of stakeholders representations, and collaborative approaches are emerging as a result. MTQ planning are now adapting to this new context and in return influence it, by a learning process

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Choub-Faha, Christophe Péguy. "Emploi régional et trafic aérien de passagers au Canada : une analyse de causalité." Master's thesis, Université Laval, 2012. http://hdl.handle.net/20.500.11794/23953.

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Les infrastructures de transport sont d’importants catalyseurs de développement régional. Réciproquement, la croissance économique favorise le développement des infrastructures de transport. Quel est le lien qui existe entre l’activité aéroportuaire de passagers (nombre de passagers embarqués/débarqués) et le développement économique régional (volume de l’emploi total) ? Ce travail de recherche examine cette relation en se concentrant sur les notions de causalité instantanée et ‘de Granger’. Nous utilisons des données annuelles couvrant la période 1988-2009 sur les quinze régions métropolitaines qui hébergent les principaux aéroports canadiens. Nos résultats concluent à l’existence des deux formes de causalité pour le Canada dans son ensemble, le Canada Central et le Canada Atlantique, que ce soit avec les variables en niveau ou en taux de croissance. Aucune relation causale n’est détectée dans les régions du Canada Pacifique et les Prairies. Lorsque l’analyse s’effectue au niveau des principaux aéroports canadiens, de nombreuses relations de causalité de Granger émergent, mettant ainsi en évidence l’étroite imbrication entre la dynamique locale de l’emploi et l’activité aéroportuaire de passagers, que ce soit pour les grands pôles économiques (Ottawa, Toronto et Montréal) ou les régions plus périphériques (notamment Régina, Saskatoon et Halifax).

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Domergue, François. "La recomposition du transport aérien de l'Est canadien." Bordeaux 4, 2002. http://www.theses.fr/2002BOR40031.

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Le dévelopement de l'ère de la mobilité, la dérèglementation du ciel, les réseaux d'alliances, la privatisation des aéroports et la tragique actualité nécessitent une analyse du transport aérien souvent considérée comme marginale par la science économique. L'enjeu de cette thèse réside dans l'intégration des mutations et défis reliés au processus de recomposition du transport aérien au sein d'une étude des aéroports de Montréal et de Toronto. Nous examinons en premier lieu, le contexte éco-politique et règlementaire du transport aérien ; une analyse quantitative des gestionnaires et transporteurs de l'est Canada et de leurs stratégies de développement. Dans un deuxième temps, nous présentons une analyse qualitative des principaux acteurs du transport aérien et nous tentons de définir une approche éco-stratégique par le calcul des impacts économiques, direct, indirect et induit des deux aéroports. Puis nous abordons le processus de manière interactive par une réflexion prospective à l'aide de l'analyse morphologique. La méthode des scenarii et l'identification des stratégies des acteurs. . . .

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Ingelaere, Raynald. "Gestion et (re)structuration de deux grandes aires métropolitaines : les transports urbains à Lille et à Montréal." Phd thesis, Toulouse 2, 2002. https://tel.archives-ouvertes.fr/tel-00863425.

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Depuis les années 1950, le décalage observé entre aire urbaine et pouvoir politique est à la source d'un dysfonctionnement majeur des agglomérations (effets de débordements. . . ). En réaction, de nombreux Etats engagent une reconfiguration politico-administrative des territoires reposant sur des héritages historiques et des techniques juridiques spécifiques. Cette (re)structuration impose l'échelle des territoires fonctionnels comme cadre de résolution des problèmes urbains (aménagement, urbanisme, réseaux. . . ). L'organisation et l'exploitation des réseaux de transport collectif urbain sont symptomatiques des difficultés rencontrées par les agglomérations. Du fait de son importance (mobilité, dimensions économique et sociale); et de ses difficultés, le transport urbain est confié aux nouvelles structures métropolitaines: toutefois, les formes institutionnelles et les instruments de régulation et de contrôle mis en place vont dépendre de facteurs endogènes aux agglomérations ou de contextes nationaux spécifiques. Le transport devient l'une des principales préoccupatuions des pouvoirs publics. Puis, avec l'interêt croissant porté à la durabilité urbaine, avec la métropolisation économique, il apparaît comme le pivot central des politiques métropolitaines. Sur la base d'une comparaison entre les aires métropolitaines de Lille et de Montréal, notre étude se propose de déterminer: dans quelle mesure la (re)structuration progressive d'une agglomération favorise la mise en place de politiques métropolitaines, notamment en matière de transport collectifs; quels organismes (intercommunalités) ou organisations (gouvernance) concourent à une meilleure gestion de la métropole (services et politiques); quelles politiques de transport collectif ont été développées par les pouvoirs publics, dans quels cadres elles se sont inscrites et quels en ont été les résultats, ou l'influence sur la ville elle-même
Since 50's, the altering between urban area and political power is at the origin of a major dysfunction of agglomerations (spillovers. . . ). In reaction, many States have implemented a political and administrative reconfiguration of territories, lying upon historical heritage and specific legal techniques. This restructuring necessitates a definition of functional areas as a frame for the resolution of urban problems (planning, urbanism, network. . . ). The organization and the management of urban transport network are symptomatic of the difficulties met by urban areas. Because of its repercussions on urban life development (mobility, economic and social dimensions) and the problems it must deal with, the urban transport has been put into the hands of new metropolitan structures: the nature of institutional forms, regulation and control instruments will depend, however, on endogenous metropolitan factors or the specific national context. Transport has become one of the principal preoccupations of public powers. So, with the growing interest in urban sustainability, with the economic metropolisation, it appears to be the central pivot of metropolitaan politics. On the basis of a comparison between the metropolitan areas of Lille and Montreal, our study means to determine: to what extent the progressive structuring of an urban area facilitates the setting of metropolitan politics; which organsims (intermunicipal arragements) or organizations (governace) concur to a better administration of the metropolis (services and politics); which politics of urban transport were developed by public powers, in which frame they were elaborated and what were their results or their impact on the city itself

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Bougas, Constantinos. "Forecasting Air Passenger Traffic Flows in Canada : An Evaluation of Time Series Models and Combination Methods." Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/30093/30093.pdf.

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Ces quinze dernières années, le transport aérien a connu une expansion sans précédent au Canada. Cette étude fournit des prévisions de court et moyen terme du nombre de passagers embarqués\débarqués au Canada en utilisant divers modèles de séries chronologiques : la régression harmonique, le lissage exponentiel de Holt-Winters et les approches dynamiques ARIMA et SARIMA. De plus, elle examine si la combinaison des prévisions issues de ces modèles permet d’obtenir une meilleure performance prévisionnelle. Cette dernière partie de l’étude se fait à l’aide de deux techniques de combinaison : la moyenne simple et la méthode de variance-covariance. Nos résultats indiquent que les modèles étudiés offrent tous une bonne performance prévisionnelle, avec des indicateurs MAPE et RMSPE inférieurs à 10% en général. De plus, ils capturent adéquatement les principales caractéristiques statistiques des séries de passagers. Les prévisions issues de la combinaison des prévisions des modèles particuliers sont toujours plus précises que celles du modèle individuel le moins performant. Les prévisions combinées se révèlent parfois plus précises que les meilleures prévisions obtenues à partir d’un seul modèle. Ces résultats devraient inciter le gouvernement canadien, les autorités aéroportuaires et les compagnies aériennes opérant au Canada à utiliser des combinaisons de prévisions pour mieux anticiper l’évolution du traffic de passager à court et moyen terme. Mots-Clés : Passsagers aériens, Combinaisons de prévisions, Séries temporelles, ARIMA, SARIMA, Canada.
This master’s thesis studies the Canadian air transportation sector, which has experienced significant growth over the past fifteen years. It provides short and medium term forecasts of the number of enplaned/ deplaned air passengers in Canada for three geographical subdivisions of the market: domestic, transborder (US) and international flights. It uses various time series forecasting models: harmonic regression, Holt-Winters exponential smoothing, autoregressive-integrated-moving average (ARIMA) and seasonal autoregressive-integrated-moving average (SARIMA) regressions. In addition, it examines whether or not combining forecasts from each single model helps to improve forecasting accuracy. This last part of the study is done by applying two forecasting combination techniques: simple averaging and a variety of variance-covariance methods. Our results indicate that all models provide accurate forecasts, with MAPE and RMSPE scores below 10% on average. All adequately capture the main statistical characteristics of the Canadian air passenger series. Furthermore, combined forecasts from the single models always outperform those obtained from the single worst model. In some instances, they even dominate the forecasts from the single best model. Finally, these results should encourage the Canadian government, air transport authorities, and the airlines operating in Canada to use combination techniques to improve their short and medium term forecasts of passenger flows. Key Words: Air passengers, Forecast combinations, Time Series, ARIMA, SARIMA, Canada.

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Cisse, Yahya Ibrahima. "Trafic aérien de passagers au Canada : analyse exploratoire d'un modèle origine-destination avec interactions spatiales." Master's thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/26457.

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Ce mémoire revisite à l’aide de méthodes d’économétrie spatiale le modèle gravitaire PODM (Passenger Origin-Destination Model) que Transports Canada utilise pour prédire le trafic aérien domestique de passagers. Différents modèles spatiaux de panel sont estimés par maximum de vraisemblance et par la méthode des moments. Les résultats montrent que l’approche traditionnelle ne détecte pas d’effets de la distance entre l’origine et la destination sur le volume du trafic intérieur de passagers. Ce sont les caractéristiques de la région d’origine et de destination (PIB, revenu disponible, population) et les caractéristiques du trajet (prix moyen du billet, nombre de vols offerts) qui sont les déterminants les plus importants des flux de passagers. Dans les modèles spatiaux explorés, les interactions spatiales se révèlent d’importants déterminants aux côtés des caractéristiques locales. La prise en compte de ces effets spatiaux pourrait permettre d’améliorer les prévisions de trafic de passagers au Canada. Mots clés : interactions spatiales, données de panel, maximum de vraisemblance, méthodes des moments.

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Leclerc, Richard. "L'émergence de la politique aérienne internationale du Canada de 1994 : une innovation pour le déploiement de routes transpacifiques." Master's thesis, Université Laval, 2002. http://hdl.handle.net/20.500.11794/34278.

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Ce mémoire avait pour objectif d'appliquer le modèle d’émergence des politiques publiques développé par John W. Kingdon à l’analyse des courants à l'origine de la politique aérienne internationale du Canada de 1994 et des traités qui lui sont concomitants. Portant sur la décennie 1990 et sur la région Asie-Océanie comme espace géographique, la recherche a permis d'investir les enjeux du transport aérien international pour le Canada, d'évaluer les mécanismes ayant porté à l'ordre du jour l'élaboration d'une nouvelle politique. En 1991, le Groupe de travail ministériel sur la politique internationale de l'air a offert des propositions de réforme. Le développement des relations bilatérales entre le Canada et des pays de l’Asie-Océanie, ainsi que l'accroissement du nombre de Canadiens d'origine asiatique dans les années 1980 et 1990 ont contribué à attirer l'attention d’Air Canada et des Lignes aériennes Canadien International sur cette région en vue d'accroître leurs revenus.
Québec Université Laval, Bibliothèque 2019

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Jannin, Géraldine. "L'information des voyageurs : études comparative : les systèmes d'information voyageurs : quelle(s) stratégie(s) de communication ?" Bordeaux 3, 2000. http://www.theses.fr/2000BOR30052.

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Jusqu'aux annees quatre-vingt, l'information des voyageurs ne constituait pas une priorite pour les entreprises de transport collectif urbain dans les pays industrialises. Centree sur la fonction "transport", la communication avec les voyageurs semblait une dimension oubliee par les entreprises. Des nouvelles pressions, liees aux mutations contextuelles (urbanistique, economique, politique et sociales), ont cependant modifie le cadre de reference traditionnel de ces entreprises et place celles-ci face a de nouvelles exigences notamment, celle de communiquer avec les voyageurs. Si ces entreprises ont su s'approprier les innovations en matieres de technologie de l'information et de la communication, la demarche comparative retenue (france, quebec) revele, qu'a developpement technologique comparable, les politiques d'information des voyageurs mises en oeuvre par les entreprises de transport public urbain, suivent des voies diversifiees selon les pays et s'inscrivent dans un processus socialement construit.

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Villeneuve, Dominic. "La nouvelle prédominance du mode partenariat public-privé dans la production de tramways au Canada." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/26137.

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Afin de comprendre pourquoi tous les nouveaux projets de tramways en cours de développement au Canada sont réalisés en mode partenariat public-privé (PPP) plutôt que grâce au mode traditionnel (gestion publique) utilisé par le passé, cette recherche porte sur trois projets de tramways présentement en cours de réalisation (Edmonton, Ottawa et Toronto). À l’aide de trois études de cas, nous explorons l’argumentaire entourant chacune des décisions menant au choix du mode de gouvernance PPP ainsi que la forme prise par ce PPP. Nous démontrons que dans tous les cas, il est possible d’observer les mécanismes du transfert de politique, tant volontaire que coercitif. Nous croyons que le transfert de politique peut donc fournir un élément de réponse à notre question. De plus, l’argumentaire utilisé par les acteurs locaux pour justifier le choix du mode PPP, bien que semblable sur plusieurs points, comporte tout de même une combinaison de justifications unique à chacun des cas, ce qui nous laisse croire que le PPP est un instrument de politique polyvalent. Ces constats démontrent l’intérêt de prendre en considération les transferts de politique au niveau municipal et non seulement les transferts qui prennent place entre les États nationaux. To understand why all new light rail projects under development in Canada are carried out in public-private partnership (P3) rather than through the traditional mode (public administration) that prevailed in the past, this research explores three light rail projects currently underway in Edmonton, Ottawa and Toronto. We study the arguments surrounding each decision leading to the choice of P3 governance. We show that in all cases, it is possible to observe the mechanisms of policy transfer, whether voluntary or coercive. Moreover, the argument used by local actors to justify the choice of P3, although similar in several respects, still forms a unique combination of justifications for each case, which leads us to believe that P3s are a versatile policy instrument. These findings demonstrate the importance of taking into account policy transfer at the municipal level and not only transfers that take place between national states.

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Blais, Ghislain. "Le Drummond County Railway : 1886-1900." Master's thesis, Université Laval, 2006. http://www.theses.ulaval.ca/2006/23904/23904.pdf.

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Ma, Fengshan. "Plasmodesmata and symplastic transport in onion (Allium cepa L.) roots." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0026/NQ51210.pdf.

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Mayer, Klaus Ulrich. "A numerical model for multicomponent reactive transport in variably saturated porous media." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq38256.pdf.

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VanderKwaak, Joel E. "Numerical simulation of flow and chemical transport in integrated surface-subsurface hydrologic systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0012/NQ38276.pdf.

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Le, Blanc Mario 1960. "A guide for drafting bilateral air transport agreements in Canada /." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66215.

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Brush, David J. "Three-dimensional fluid flow and solute transport in rough-walled fractures." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ60525.pdf.

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Cisne, Júnior Roberto Lima da Costa. "Transporte de partículas em canais catraca." reponame:Repositório Institucional da UFC, 2009. http://www.repositorio.ufc.br/handle/riufc/12887.

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CISNE JÚNIOR, Roberto Lima da Costa. Transporte de partículas em canais catraca. 2009. 66 f. Dissertação (Mestrado em Física) - Programa de Pós-Graduação em Física, Departamento de Física, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2009.
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In this work we study the transport process of fluid flow and mass through channels that are characterized by periodic structures, namely ratchet channels. In the first part of this work, we approach a brief discussion on the characteristics of the flow in smooth channels, since they have simple analytical solution, and may help us understand the fluid flow through more complex channels. Then we study the fluid flow in ratchet channels, and we compare the results obtained for the fluid flow through smooth and ratchet channels, observing some similarities and differences between both of them. We show that the nature of the geometry of the ratchet channel adds a degree of complexity to the problem of the fluid flow, that affects the properties of the velocity and pressure fields. Moreover, we inquire into another aspect of the transport process, namely the transport of massive particle dragged by a fluid that flows in the interior of the ratchet channels previously mentioned. We show some results that indicate a certain typical similatiry between ratchet and smooth channels. However, the ratchet channels possess a structure that allows the break of symmetry in relation of the two only allowed directions of flow. In this way, the nature of the particle transport process can be affected by this break of simmetry. The aim of this work is to analyze the dynamics of particle transport into a ratched channel and determine which mechanisms play a fundamental role in this process.
Neste trabalho trataremos do transporte de fluido e partículas no interior de canais caracterizados por estruturas periódicas que lembram dentes de catraca, desta forma chamamos de canais catraca. Para tal tarefa iniciaremos com uma breve discussão sobre as características do escoamento em canais lisos, visto que os mesmos possuem solução analítica simples, e poderão nos ajudar a compreender o escoamento em canais mais complexos. Em seguida faremos o estudo do escoamento em canais catraca, e faremos a comparação entre os resultados obtidos para o escoamento em canais lisos e em canais catraca, mostrando algumas semelhanças e diferenças. Mostramos que a natureza da geometria do canal catraca adiciona um grau de complexidade ao problema do escoamento, refletindo-se nas propriedades dos campos de velocidade e pressão. Em seguida, faremos o estudo do comportamento do transporte de partículas com massa arrastadas por um fluido escoando no interior dos canais catraca, mostrando alguns resultados que indicam uma certa característica típica de canais lisos. Porém, devido os canais catracas possuírem uma estrutura que permite a quebra de simetria em relação aos dois únicos sentidos de fluxo permitidos, poderão aparecer mudanças no comportamento tanto do transporte de fluido como do transporte de partículas. Como ponto principal deste trabalho, analisaremos como surgem estas diferenças e quais os mecanismos desempenham papel fundamental para que isto aconteça.

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Hayashi, Masaki. "Surface-subsurface transport cycle of chloride induced by wetland-focused groundwater recharge." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq21353.pdf.

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Cholewa, Ewa M. "Calcium transport and delivery to the xylem in onion (Allium cepa L.) roots." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0023/NQ51185.pdf.

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Katsivela, Maria-Eleftheria. "Multimodal carrier liability in the United States and Canada : towards uniformity of applicable rules ?" Nantes, 2004. http://www.theses.fr/2004NANT4008.

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Dès sa naissance, le transport intermodal a servi le commerce, les chargeurs et les transporteurs, augmentant de façon importante le transport des marchandises au niveau mondial. Pourtant, les règles de responsabilité du transporteur multimodal n'ont pas évolué au même rythme et restent fragmentées à travers les modes et les pays. C'est aussi le cas des États-Unis et du Canada. Le besoin de chercher l'uniformité des règles applicables nous a conduit à l'étude comparée des règles unimodales (terrestres-maritimes) dans ces deux pays. Guidés par l'échec des initiatives passées (Convention de Nations Unies sur le Transport Multimodal' International des Marchandises, 1980), la réalité intermodale européenne, la déréglementation du transport, le pragmatisme, la justice dans le rapport entre le transporteur et le chargeur et l'analyse économique de droit, nous avons utilisé l'harmonisation, la codification et le contractualisme en vue d'avancer nos suggestions sur des règles de responsabilité uniformes du transporteur multimodal
From its inception, intermodal transport of goods has served trade, shippers and carriers, radically increasing transactions of goods worldwide. Multimodal carrier liability rules, however, have not evolved with the same rhythm and remain fragmented cross-modally and cross-country. This is also the case of the U. S. And Canada. The need to seek uniformity of applicable rules in these two countries led us to the comparative analysis of unimodal (land-ocean) rules in these two countries. Guided by past failed initiatives (1980 United Nations Convention on International Multimodal Transport), the European intermodal reality, transport deregulation, pragmatism, fairness in the relation between the carrier and the shipper and Law & Economics principles, we used harmonization, codification and contractualism in advancing our suggestions on uniform multimodal carrier liability rules

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March, Nicole Martins de. "Transporte coerente em canais iônicos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/103868.

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Processos biológicos e efeitos quânticos parecem ocupar realidades diferentes uma vez que os organismos são constantemente sujeitos a ruídos introduzidos pelo meio. Esses ruídos tendem a destruir a coerência quântica fazendo com que processos clássicos dominem a dinâmica do sistema. Porém, recentemente, com a descoberta da ocorrência de processos coerentes no transporte de excitações em complexos fotossintéticos, a área denominada como Biologia Quântica começou a receber mais atenção. O mais intrigante é que, nesses complexos fotossintéticos, dependendo da combinação do ruído do meio com o processo coerente, um aumento na eficiência do transporte poderá ser observada. Com esses resultados, questões fundamentais como a de que sistemas biológicos poderiam tirar vantagens da Mecânica Quântica surgem naturalmente. Nesse estudo, analisamos se o tunelamento coerente poderia explicar a alta eficiência observada em um canal iônico de potássio. Plenio e colaboradores [1] argumentaram que o tunelamento coerente e o ruído dephasing pode explicar a alta taxa de transporte nos canais iônicos. Discutimos também se o mesmo ocorre com o ruído térmico. Baseando-se nas hipóteses feitas por Plenio [1], analisamos o efeito do ruído térmico concluindo que o mesmo pode melhorar a condutividade, mas também pode impor restrições, uma vez que o tempo de coerência diminui severamente.
Quantum e ects and biological processes seem to occupy di erent realms, given that organisms are constantly subjected to noise from the environment. Noise processes tend to destroy the coherence of the system, hence classical processes are expected to dominate the dynamics. Nevertheless, with the recent discovery that coherent processes occur in the excitation energy transport in photosynthetic complexes, the area known as Quantum Biology started receiving special attention. The most interesting point here is that in these photosynthetic complexes the right interplay between noise and quantum coherence seems to improve transport e ciency. In this dissertation we investigate whether coherent tunneling could explain the high e ciency observed in ion channels. It has been argued by Plenio et al [1] that coherent tunneling and dephasing noise can explain the high conductance in ionic channels. We have analyzed whether the same occurs when thermal noise are also taken into account. Based on Plenio et al [1] assumptions, we have analysed the e ect of thermal noise to conclude that it can improve conductivity but can also impose restrictions since the coherence time is severely diminished.

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JÃnior, Roberto Lima da Costa Cisne. "Transporte de partÃculas em canais catraca." Universidade Federal do CearÃ, 2009. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2608.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
Neste trabalho trataremos do transporte de fluido e partÃculas no interior de canais caracterizados por estruturas periÃdicas que lembram dentes de catraca, desta forma chamamos de canais catraca. Para tal tarefa iniciaremos com uma breve discussÃo sobre as caracterÃsticas do escoamento em canais lisos, visto que os mesmos possuem soluÃÃo analÃtica simples, e poderÃo nos ajudar a compreender o escoamento em canais mais complexos. Em seguida faremos o estudo do escoamento em canais catraca, e faremos a comparaÃÃo entre os resultados obtidos para o escoamento em canais lisos e em canais catraca, mostrando algumas semelhanÃas e diferenÃas. Mostramos que a natureza da geometria do canal catraca adiciona um grau de complexidade ao problema do escoamento, refletindo-se nas propriedades dos campos de velocidade e pressÃo. Em seguida, faremos o estudo do comportamento do transporte de partÃculas com massa arrastadas por um fluido escoando no interior dos canais catraca, mostrando alguns resultados que indicam uma certa caracterÃstica tÃpica de canais lisos. PorÃm, devido os canais catracas possuÃrem uma estrutura que permite a quebra de simetria em relaÃÃo aos dois Ãnicos sentidos de fluxo permitidos, poderÃo aparecer mudanÃas no comportamento tanto do transporte de fluido como do transporte de partÃculas. Como ponto principal deste trabalho, analisaremos como surgem estas diferenÃas e quais os mecanismos desempenham papel fundamental para que isto aconteÃa.
In this work we study the transport process of fluid flow and mass through channels that are characterized by periodic structures, namely ratchet channels. In the first part of this work, we approach a brief discussion on the characteristics of the flow in smooth channels, since they have simple analytical solution, and may help us understand the fluid flow through more complex channels. Then we study the fluid flow in ratchet channels, and we compare the results obtained for the fluid flow through smooth and ratchet channels, observing some similarities and differences between both of them. We show that the nature of the geometry of the ratchet channel adds a degree of complexity to the problem of the fluid flow, that affects the properties of the velocity and pressure fields. Moreover, we inquire into another aspect of the transport process, namely the transport of massive particle dragged by a fluid that flows in the interior of the ratchet channels previously mentioned. We show some results that indicate a certain typical similatiry between ratchet and smooth channels. However, the ratchet channels possess a structure that allows the break of symmetry in relation of the two only allowed directions of flow. In this way, the nature of the particle transport process can be affected by this break of simmetry. The aim of this work is to analyze the dynamics of particle transport into a ratched channel and determine which mechanisms play a fundamental role in this process.

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Dufresne, Yves. "La Réglementation économique du transport aérien intérieur au Canada : aspects juridiques et politiques." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63209.

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Lemieux, Christine. "La coopération politique bilatérale entre le Canada et les États-Unis dans le secteur énergétique : l'harmonisation des normes de fiabilité reliées au transport de l'électricité." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99730.

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Do domestic variables matter in a context of bilateral cooperation? What factors positively influence the decision-making process in the case of a policy harmonization between two countries? By studying both countries' institutional differences and governmental and non-governmental actors' preferences in the energy sector, this research analyzes the bilateral cooperation between Canada and the United States regarding the creation of the Electric Reliability Organization. Although domestic institutional constraints are important to consider, I argue that both physical and economic market integration and the use of a non-governmental organization by central governments have facilitated the success of the cooperation process. Those factors have favored the convergence of decisional actors' preferences and the inclusion of the majority of actors from all sectors of the industry into the process. The analysis uses a sequential model implying the division decision-making process over foreign policy into specific stages to show the importance of domestic variables.
Key words: Governmental cooperation, bilateral relations, actors' preferences, institution, energy sector, electricity, transmission network, reliability standards, market integration, restructured electricity market.

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Wilkes, Jason John. "Insulin signalling can regulate glucose transport in muscle independently of changes in total GLUT-4, effects of muscle activity and high-fat-feeding on the insulin signal Akt." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ53995.pdf.

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Jolivel, Maxime. "Érosion du pergélisol, transport fluvial et sédimentation marine, côte est de la baie d'Hudson, Nunavik, Canada." Doctoral thesis, Université Laval, 2014. http://hdl.handle.net/20.500.11794/25562.

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Cette thèse présente une étude du système érosion-transport-sédimentation en milieu de thermokarst dans un contexte de réchauffement climatique. La zone d’étude comprend le bassin versant de la rivière Sheldrake, 5 km au nord du village Umiujaq au Nunavik, ainsi qu’une zone de 15 km2 au large de son embouchure, dans le Passage de Nastapoka, en baie d’Hudson. Trois axes majeurs sont considérés: 1- l’étude des conditions de pergélisol et l’estimation quantitative des masses et volumes de sédiments et de carbone érodés à l’échelle du bassin versant ; 2- la mesure du régime hydrologique et sédimentaire du principal vecteur de transport, la rivière Sheldrake ; 3- la bathymétrie, la sédimentologie et la mesure des apports sédimentaires et organiques dans le milieu marin côtier au large de l’embouchure de la rivière. Dans le bassin versant de la rivière Sheldrake, le pergélisol s’est considérablement dégradé au cours des 50 dernières années, particulièrement dans la toundra forestière. La subsidence des lithalses, des palses, des plateaux de pergélisol et des plateaux palsiques engendre la formation de mares de thermokarst. De nombreux glissements de terrain et des ravins d’érosion sont également actifs et favorisent le rejet de sédiments dans le réseau fluvial. Avec la dégradation du pergélisol, la connectivité hydrologique augmente, ce qui facilite l’évacuation des sédiments et du carbone via le cours d’eau principal. Dans cet environnement thermokarstique, la charge sédimentaire fluviale en suspension est plus importante en été alors que les températures élevées de l’air commandent le dégel des sols, favorisant l’activation des ostioles et le déclenchement des glissements de terrain. Les pluies estivales permettent le transport et l’évacuation des sédiments en baie d’Hudson. Parvenus en mer, les sédiments et le carbone transportés en suspension subissent une forte dispersion à cause de l’intensité des courants marins du Passage de Nastapoka. Il en résulte l’absence d’une augmentation mesurable du taux de sédimentation. En revanche, la composition isotopique du carbone sédimentaire montre que la fraction terrigène a augmenté depuis le Petit Âge Glaciaire et que ce phénomène s’est considérablement accéléré vers la fin du 20ème siècle. Il est suggéré que la dégradation du pergélisol contribue à cette augmentation, quoique ce ne soit pas le seul facteur qu’on puisse invoquer.
This thesis studies the system erosion-transport-sedimentation in a thermokastic area, in a context of warming climate. The study area encompasses the catchment of the Sheldrake River, 5 km north of the village Umiujaq, Nunavik, and a 15 km2 area off its mouth, in the Nastapoka Sound, in Hudson Bay. Three main axes are considered: 1- study of permafrost conditions and quantitative estimate of the volumes and masses of eroded sediment and organic carbon at the scale of the catchment; 2- measurements of the hydrological and sedimentary regime of the main vector of transport, the Sheldrake River; 3- bathymetry, sedimentology and measurements of mineral and organic inputs in the coastal marine environment, off the river mouth. In the Sheldrake River catchment, permafrost has considerably degraded during the last 50 years, particularly in the forested tundra. Subsidence of lithalsas, palsas, permafrost plateaus and peat plateaus leads to the formation of thermokarst ponds. Many landslides and erosion gullies are also active and favor inputs of sediments in the fluvial network. Because of permafrost decay, hydrological connectivity increases, facilitating evacuation of sediment and carbon through the river. In this thermokarstic environment, the fluvial sedimentary load in suspension is more important during summer when high air temperatures provoke soils thawing, favoring frostboils activation and triggering of landslides. Summer rainfalls allow sediment transport and evacuation in Hudson Bay. Once in the sea, the sediments and carbon in suspension are dispersed because of the intensity of the marine currents in the Nastapoka Sounds. This results in an absence of a measurable increase of sedimentation rates. However, the isotopic composition of sedimentary carbon shows that the terrestrial fraction has increased since the Little Ice Age and that this trend has significantly accelerated since the end of the 20th century. It is suggested that permafrost decay contributes to this increase, although it is not the only proposed source.

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Forest, Patrick. "Approvisionnements transfrontaliers locaux en eau potable entre le Canada et les États-Unis : Reconsidérations sur le thème de transfert d'eau." Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26509/26509.pdf.

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L’étude du domaine international, très souvent orientée vers les relations interétatiques, trouve dans cette thèse un débouché à un autre niveau : celui des relations interlocales. À l’ombre des hypothétiques projets de transferts massifs d’eau existent ce que nous avons qualifié d’approvisionnements transfrontaliers locaux en eau potable, soit des adductions destinées à l’approvisionnement en eau entre communautés jumelles situées le long de la frontière entre le Canada et les États-Unis. Il s’agit des seuls transferts d’eau en vrac existants entre les deux pays à l’heure actuelle. Compte tenu de l’absence d’études approfondies sur le sujet, une meilleure compréhension de ce phénomène se révèle essentielle. La thèse s’articule autour de deux questions de recherche principales. Comment ces échanges sont-ils spatialement structurés ? Quelles sont leurs caractéristiques et leurs conséquences juridiques dans le contexte de l’ALÉNA ? Le premier chapitre présente le cadre normativo-institutionnel d’une recherche s’inscrivant dans le domaine international selon une perspective interdisciplinaire conciliant la géographie et le droit. Le deuxième chapitre énonce le cadre conceptuel de la thèse et sa contribution à l’étude des transferts d’eau, de la pénurie d’eau en tant que construit social et du concept de cycle hydrosocial. Le troisième chapitre expose la méthodologie, laquelle conjugue les méthodes qualitatives et juridiques; recension exhaustive des approvisionnements transfrontaliers locaux, analyse des documents juridiques, sélection d’études de cas et réalisation de séjours sur le terrain et d’entrevues semi-dirigées. Le quatrième chapitre présente les résultats de la recherche en quatre sections. La première consiste en une base de données dévoilant et qualifiant les onze types d’approvisionnements transfrontaliers recensés. La deuxième section développe en profondeur trois études de cas. La troisième section porte sur le cycle hydrosocial et l’apport de l’approche géo-légale. La quatrième section situe la perception des acteurs. Le cinquième chapitre explore les implications juridiques de ces transferts pour le Canada. Il est montré que ceux-ci ne constituent pas une menace pour le Canada dans le cadre de l’ALÉNA. Dans l’éventualité où les pouvoirs publics souhaiteraient mieux encadrer ces transferts, il est ensuite précisé au chapitre 6 ce que pourrait constituer une politique publique des approvisionnements transfrontaliers locaux.
While studies within international fields are often dedicated to understanding the nature of interstate relationships, this research is devoted to the interlocal scale. In the shadow of hypothetical, continental water transfers, there exist transboundary local freshwater supplies, or water adductions apportioned to supply water between twin communities located along the border between Canada and the United States. These constitute the only contemporary, bulk water transfers between the two countries. A better understanding of this phenomenon is needed in the absence of any in-depth studies focusing on these local water transfers. This dissertation is organized around two main research questions: How are these transfers spatially organized ? What are the legal characteristics and consequences of these transfers within the context of NAFTA ? The first chapter begins by introducing the normative-institutional frame of the study, which is both international in scope and interdisciplinary, bringing together geography and law. The conceptual frame of this research and its contribution to the study of water transfers, water scarcity as social construction, and the concept of hydrosocial cycle comprise the second chapter. The third chapter explores the methodology located at the interface between geography and law. It includes an exhaustive survey of local transboundary water supplies, an analysis of legal documents, case studies, fieldwork, and semi-structured interviews. The results of this research are presented in the fourth chapter and divided into four sections. The first section represents a database describing the eleven local transboundary water supplies surveyed, followed by an in-depth analysis of three case studies. The third section relates to the hydrosocial cycle and the contribution of the geo-legal perspective while the fourth builds upon local and national actors’ perceptions. The fifth chapter explores the legal consequences of these transfers for Canada, arguing that these transfers do not constitute any potential threat for Canada within the context of NAFTA. The final chapter elucidates what a public policy of local transboundary water supplies could look like if public authorities (i.e. federal and provincial governments) chose to assert more control over these transfers.

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Humphrey, Donald B. "Characterizing ballast water as a vector for nonindigenous zooplankton transport." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2391.

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The global movement of aquatic non-indigenous species can have severe ecological, environmental and economic impacts emphasizing the need to identify potential invaders and transport pathways. Initial transport is arguably the most important stage of the invasion process owing to its role in selectively determining potential invasion candidates. This study characterizes a well defined human-mediated dispersal mechanism, ballast water transport, as a vector for the introduction of non-indigenous zooplankton. Ballast water exchange in the open ocean is the most widely adopted practice for reducing the threat of aquatic invasions and is mandatory for most foreign vessels intending to release ballast in Canadian waters. Ships entering Canadian ports are categorized into the following three shipping classes based on current regulations: overseas vessels carrying exchanged ballast water, intra-coastal vessels carrying exchanged ballast water or intra-coastal vessels carrying un-exchanged ballast water. This study characterizes zooplankton communities associated with each of these shipping classes sampled from ports on Canada’s Pacific coast, Atlantic coast and the Great Lakes Basin. Ballast water samples were collected and analyzed from 77 vessels between 2006 - 2007. The ballast water environment was found to be diverse, with over 193 zooplankton taxa, 71 of which were non-indigenous to their receiving environments. Intracoastal vessels containing un-exchanged coastal water transported the greatest density of non-indigenous zooplankton into Canadian ports. Total zooplankton density was found to be negatively correlated with ballast water age The absence of mandatory ballast water exchange and the younger ballast water age of coastal un-exchanged vessels is likely responsible for the higher density of non-indigenous zooplankton in intracoastal un-exchanged vessels. Propagule pressure, invasion history and environmental suitability are all useful in evaluating invasion potential and all suggest that intracoastal un-exchanged vessels pose the greatest invasion threat to Canadian aquatic ecosystems. In conclusion, although the risk of primary introductions from overseas ports may have been reduced through open-ocean exchange of ballast water, secondary introductions from previously invaded ports in North America may be the primary threat to Canadian aquatic ecosystems via this transport vector.

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Gadhoum, Yoser. "Analyse de quelques caractéristiques et performances du secteur du transport aérien au Canada avant et après dérèglementation." Thesis, University of Ottawa (Canada), 1989. http://hdl.handle.net/10393/5860.

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Moreau, Laurent. "La bicyclette comme moyen de transport au Canada : le cas de la région de la Capitale nationale." Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/9623.

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A large database was produced from a survey held in the summer of 1991 on commuters who cycle to work in downtown Ottawa. Social reasons underly this type of commuting which a majority of cyclists practice seven months a year. Cyclists perceive acutely the dangers of sharing the road with motor vehicles therefore are pushed to demand more bike paths despite the fact that well-thought integration to the entire road system is preferable. The potential of the bicycle as a transportation means in an urban environment is demonstrated. However research should be initiated to design a bicycle better suited to the Canadian climate.

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Lemoyne, François. "L'équilibre général et la prévision énergétique : étude du modèle d'analyse des politiques liées à l'énergie au Canada." Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/30059/30059.pdf.

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Mon mémoire s’articule autour de deux objectifs distincts. En premier lieu, je présente un modèle d’équilibre général utilisé par Ressources Naturelles Canada pour obtenir des prévisions énergétiques sur l’économie canadienne : le modèle d’analyse des politiques liées à l’énergie au Canada, ou MAPLE-C. En deuxième lieu, je réalise une étude de cas avec MAPLE-C sur la mise en œuvre d’une politique publique obligeant l’utilisation du gaz naturel compressé par le transport lourd et sa conséquence sur l’émission de gaz à effet de serre. J’observe une réduction globale des gaz à effet de serre alors que le transport lourd utilise une source d’énergie moins polluante que le pétrole. J’observe aussi un réajustement de l’économie alors que les consommateurs abandonnent le gaz naturel, devenu plus cher. Toutefois, dû aux limitations du modèle, je suis dans l’impossibilité de statuer sur les effets positifs et négatifs.

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Oliveira, Emanuel José Reis de. "Estudos sobre canais de transporte em camadas de GaAs/GaMnAs." Universidade do Estado do Rio de Janeiro, 2010. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2065.

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Propostas de construção de dispositivos que unem a eletrônica com a spintrônica utilizando compostos semicondutores magnéticos diluídos (DMS) tem se tornado cada mais frequentes junto à comunidade científica em geral. Em particular, por suas propriedades magnéticas e de transporte hoje conhecidas, camadas de GaAs/GaMnAs pertencem a um grupo de DMS com grandes possibilidades de utilização prática. Nesse sentido, entender suas propriedades de transporte é essencial para o desenvolvimento dessa nova área. Investigamos o transporte spin polarizado em nanocamadas de GaAs/GaMnAs que exibem uma fase ferromagnética abaixo de certa temperatura de transição de fase. Como procedimento de pesquisa, nosso cálculo da resistividade considerou a existência de uma banda de impureza que determina a natureza do estado no nível de Fermi e dos estados próximos a ele como estendidos (condução "metálica") ou localizados (condução por excitação térmica). A ordem magnética e a resistividade são interligados devido à influência da polarização de spin da banda de impurezas e um efeito tipo separação Zeeman sobre a mobility edge (1). Obtivemos para um dado intervalo de concentração de manganês e de portadores, um comportamento metálico em que o transporte por estados estendidos domina em baixas temperaturas e é dominado por um processo de excitação térmica dos estados localizados para temperaturas próximas e acima da temperatura de transição. O resultado dessa combinação de canais de condução foi o aparecimento de uma lombada na resistividade, a qual tem sido observada experimentalmente, e traz esclarecimentos sobre a relação entre as propriedades de transporte e magnéticas desse material. (1) Embora a expressão possa ter uma tradução, é comumente usada na área em inglês.
Construction proposals of the contrivances that put together electronic with spintronic using diluted magnetic semiconducting compounds (DMS) are more and more frequent to the scientific community in general. In particular, because of its magnetic and transporting rightnesses that has been known today, GaMnAs stratums belongs to a DMS group with great possibilities of the practical utilization. In this sense, to understand its transporting rightnesses is essential to the development in this new area. We investigate the polarized spin transport in GaMnAs nanolayers that display an ferromagnetic stage below of the specific phase transition temperature. As a procedure research, our resistivity estimate has consider the existence of an impurity band that determine the state nature in the Fermi level and the states near to it like extended (metallicconduction) or located (thermic excitation conduction). The magnetic order and resistivity are interconnected due to the influence of the spin polarization of the band of the impurities and another efect as a Zeeman separation over the moblility edge. We aquire, for a certain interval of bearings and manganese concentration, a metallic behavior in which the transport to the extended states rules in low temperatures and is ruled by an process of thermic excitation of the states located to near and over temperatures of the transition temperature. The result of this transport channels combination was the appearance of an acclivity in the resistivity that has been observed experimentally and brings elucidations about the relation between the magnetic and transporting rightnesses of this material.

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Braga, Maria Elita Duarte. "Estudo experimental dos fundamentos do transporte hidraulico de laranjas." [s.n.], 1997. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255927.

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Orientador: Carlos Alberto Gasparetto
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: No presente trabalho estudou-se as propriedades hidrodinâmicas de laranjas, indispensáveis ao desenvolvimento de um sistema de transporte hidráulico para a fruta. Como a maioria das correlações desenvolvidas para relatar comportamento de partículas em meio fluido envolve sua geometria, estudou-se a princípio o tamanho médio da laranja em termos das medidas dos três diâmetros mutuamente perpendiculares, forma em termos do grau de esfericidade, peso, volume, densidade, área projetada e área superficial. Tendo conhecimento prévio de que as indústrias de processamento de laranjas que implantaram o sistema hidráulico como meio para transportar seu produto fracassaram devido ao entupimento dos canais, procedeu-se neste trabalho um estudo detalhado do comportamento da fruta em água atentando-se para o problema ora apontado. Concluiu-se que a laranja estando sadia apresenta uma situação de equilibrio padrão com um ângulo de orientação, entre a columela central e o nível d'água, compreendido entre 14 e 25° quando imersas em água e que frutas estragadas ficam totalmente submersas, sendo este o possível motivo das obstruções e entupimentos dos canais usados para o transporte. Dentre as características hidrodinâmicas da fruta determinou-se a velocidade terminal da laranja, no caso, ascendente, no centro de um tubo cilíndrico de 0,25 m de diâmetro e 2,70 m de profundidade. A partir da velocidade terminal determinou-se o coeficiente de arraste e o efeito de parede segundo critério Kp, definido como a razão entre a velocidade terminal de uma esfera de diâmetro Dp em meio infinito e a velocidade terminal no centro de um tubo cilíndrico de diâmetro Dt. Estudou-se ainda no presente trabalho o arraste de laranjas em condições diversas de escoamento num canal de seção retangular medindo 4,00 m de comprimento x 0,20 m de largura e profundidade variável em que mediu-se a força de arraste variando-se também a altura da lâmina de água no canal. Ainda no canal foi feito um estudo do comportamento de uma fruta isolada e de um grupo de 2 e 4 laranjas durante escoamento, para todas as velocidades estudadas.
Abstract: The physical characteristics and hydrodynamic properties of oranges which are indispensable for a water transport of the fruit have been studied in this work. As most correlations developed to report the behavior of particles in a fluid media involve their geometry, at first the average size of oranges was studied in terms of the sphericity, weight, volume, projected area and surface area. Knowing beforehand that orange processing companies which implemented the hydraulic system as a means to transport their products have failed due to clogging of channels, a detailed study was conducted in this work on the behavior of the fruit in water, taking this problem into account. It was observed that, when oranges are healhy, they have a standard equilibrium situation with an orientation angle comprised between 14 and 25° when immersed in water and that spoiled fruit are totally submersed, which is probably the reason for blocking and clogging of the channels used for transportation. Among the hydrodynamic characteristics of the fruit, the terminal velocity of the orange,which in this caso is ascending, was determined, in the center of a 2.70 m deep cylindrical tube with a 0.25 m diameter.From the terminal velocity, the drag coefficient was determined and the wall effect according ,to the criterion Kp, defined as the ratio between the terminal velocity of a sphere of diameter Dp in an infinite media and the terminal velocity in the center of a cylindrical tube of diameter Dt. Also in this work the dragging of oranges was studied under several flow conditions in a channel of rectangular section with a lenght of 4.00 m X width of 0.20 m and variable depth, in which the dragging force was measured, while varying also the height of the water sheet in the channel. Another study was made in the channel on the behavior of a separate fruit and a group of 2 and 4 oranges during the flow, at all velocities studied.
Doutorado
Doutor em Engenharia de Alimentos

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Alix, Yann. "Les enjeux de la distribution géographique des flux conteneurisés canadiens sur l'espace terrestre nord-américain." Caen, 1999. http://www.theses.fr/1999CAEN1270.

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L’objectif de cette recherche doctorale est d’établir une géographie originale des flux conteneurisés canadiens dans le contexte de libre échange nord-américain. L’analyse statistique et les investigations réalisées auprès des professionnels ont permis de dégager les réalités concurrentielles exprimées à travers le processus de détournement de trafic. A l’approche modale segmentée s’est substituée une démarche de recherche intégrant les dynamiques géographiques des flux conteneurisés canadiens sur l’avant-pays maritime mondial et sur l’arrière-pays terrestre de l’Amérique du Nord. L’intensité des relations commerciales entre les régions d’Outre-mer et les marchés provinciaux a été analysée pour démontrer la signification effective et relative de l’évasion de trafic canadien vers les réseaux intermodaux concurrents des Etats-Unis. Les processus de massification et de spécialisation découlant des stratégies des acteurs de la chaîne de transport ont été analysés et des configurations intermodales différentes se sont esquissées selon que l’on se situe sur la côte orientale ou sur le côte occidentale nord-américaine. La persistance des autorités publiques dans la gestion de filières nationales de transport tend à démonter la pérennité du concept de détournement malgré l’intégration transnationale des réseaux intermodaux. Au-delà des résultats obtenus à travers cette géoscopie, l’approche « en continuum » du phénomène de détournement permet une lecture complète à plusieurs échelles géographiques de la distribution des flux conteneurisés canadiens dans une économie mondialisée.

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Goulart, Jhon Nero Vaz. "Análise experimental de escoamentos cisalhantes em canais compostos fechados." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/16204.

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A utilização de canais compostos está bastante presente nos mais diversos campos da engenharia. Na engenharia mecânica, por exemplo, os problemas estão ligados à utilização destas estruturas no interior de trocadores de calor, reatores nucleares e até mesmo em equipamentos eletrônicos. Equipamentos nos quais o maior desafio é a maximização das taxas de transferência de calor. A acuracidade das relações que determinam a transferência de calor em trocadores de calor ou reatores nucleares, passa por uma análise dinâmica destes equipamentos, visto que suas características geométricas podem ser responsáveis pela formação de estruturas coerentes dentro do escoamento principal, que podem vir a serem importantes fontes de perturbações. A proposta deste trabalho é investigar experimentalmente as características do escoamento turbulento em alguns tipos de canais compostos fechados. Utilizando como técnica experimental a anemometria de fio quente. Nesse sentido, também foi investigado a influência dos parâmetros geométricos da seção, tanto na distribuição dessas quantidades quanto nas características dinâmicas do escoamento. No primeiro tipo o fluido é forçado a escoar entre duas placas paralelas de profundidade "p" e separadas por uma distância "d". Essas placas foram fixadas a uma das paredes laterais de um canal aerodinâmico. Na segunda seção as placas foram substituídas por feixes de seções retangulares, também fixados a mesma parede. Esses feixes também eram separados por uma distância "d". Na terceira o canal aerodinâmico foi dividido em dois. Os feixes da seção precedente foram movimentados para o centro, dando origem a dois subcanais principais conectados por uma fenda de largura "d" e profundidade "p". A quarta seção é uma simplificação das seções compostas por feixe de barras. Consiste em duas semi-circunferencias de raio externo igual a 66 mm. As semi-circunferencias foram postas uma em frente a outra, separadas também por uma distancia "d" As mudanças nos parâmetros geométricos das seções, profundidade, "p", largura da fenda, "d" e comprimento da seção "L", deram origem a 20 vinte diferentes seções. Os resultados mostraram, em todas as seções, o desenvolvimento de uma camada de mistura na direção principal do escoamento. Quanto as características dinâmicas do escoamento, estas parecem ser reguladas pelos perfis médios de velocidade.
Compound channels are present in many engineering areas, for example, in nuclear reactors, in cooling systems of electronic devices and in supply water channels. On the mechanical engineering field, the problems are linked to heat exchangers, nuclear reactor fuel elements and even electronic devices, where, the challenge is the rise in heat exchange rates. However, a good prediction on the heat transfer rates in compound channels, pass through the accuracy of the relations used: the heat exchange coefficient in heat exchangers or in nuclear reactors and correlations for the friction factors in a supplying channel. The dynamic analysis of these equipments, considering fluid structure interaction, is also important, since their geometric characteristics can be responsible for the formation of coherent structures on the flow that can become important sources of disturbances. The purpose of this work is the experimental investigation of the characteristics of the turbulent flow in compound channels and the influence of the geometric parameters of the section in its dynamic characterization. By using hot wire anemometry techniques, mean quantities and Reynolds stresses distribution were investigated in four kinds of compound channels. In the first one the fluid flows between two parallel plates, both attached on the lateral wall of aerodynamic channel. These plates have as important dimensional parameters their depth, "p", and width, "d". In second configuration the plates were replaced by rectangular bars. These ones also attached on the same lateral wall, apart from each other by a distance "d". In the third test section the aerodynamic channel was spitted in two. The bars attached on the lateral wall were moved to the middle channel, giving rise to subcahnnels connected by a narrow gap, with depth "p" and width "d". The last one was a rod bundle simplification. By using two semicircles, placed in front of one each other, it was possible to create a compound channel. Again, the topology gave rise two main subchannels connected by a narrow gap. Many changes were performed in the geometric parameters during the experiments. By modifying depth, "p", width "d" and the length, "L", enable us to get twenty different test sections. The results showed a mixing layer developing in the streamwise direction. As regards mean, normal and Reynolds stresses quantities, the experiments depicted self-preserving values when made dimensionless by local scales. According to results showed here, dynamical features are mainly ruled by mean axial velocity profile characteristics.

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Filho, José Eduardo Alamy. "Modelação numérica de processos de sedimentação em escoamentos turbulentos e análise da ressuspensão em canais." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-07112006-134142/.

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O estudo do transporte de sedimentos, partindo da estimativa de estruturas turbulentas relevantes, constituiu o principal foco deste trabalho. Assim, a equação de transporte de massa (advecção-difusão) foi aplicada em conjunto com as equações de Navier-Stokes e da continuidade filtradas. Neste contexto, houve a necessidade de uma descrição conveniente da turbulência, o que ocorreu mediante a aplicação da simulação de grandes escalas acoplada a modelos de viscosidade turbulenta sub-malha. O método de fronteira imersa foi utilizado na modelação da interface sólido/fluido, representada pela geometria de fundo dos canais. As equações de Navier-Stokes filtradas e da continuidade foram resolvidas numericamente pelo método de passos fracionados, o qual estabeleceu o almejado acoplamento entre ambas. Na discretização das equações governantes foi utilizado o método de diferenças finitas, aplicado sobre malhas deslocadas. Os esquemas explícitos de Adams-Bashforth (de segunda e quarta ordens) foram utilizados no avanço temporal das velocidades do escoamento e das concentrações de sedimentos. Uma nova formulação para a velocidade de sedimentação foi desenvolvida analiticamente, enquanto que eventuais fluxos de ressuspensão foram impostos como condição de contorno no fundo do canal. Todos os códigos computacionais, que estabeleceram as diretrizes e a lógica de cálculo, foram criados no contexto deste trabalho. Os resultados obtidos indicam que a simulação de grandes escalas, associada ao método de fronteira imersa, considerando velocidade de sedimentação conforme aqui modelada, e ainda utilizando a equação de advecção-difusão para o transporte de massa, constituem ferramentas altamente adequadas à estimativa do transporte de sedimentos pela água.
The goal of this work is the research of sediment transport phenomena, deriving from outstanding turbulent eddies estimative. Thus, the mass transport equation (advection-diffusion) was connected with the filtered Navier-Stokes and continuity equations. In this context, the large-eddy simulation and sub-grid viscosity modeling established a convenient description of turbulence effects. The immersed boundary method was applied to model solid/fluid interface, represented here by the shapes of channel bottom. The filtered Navier-Stokes and continuity equations were solved by the fractional step method. The equations were discretized with the finite difference method, applied over staggered grids, whereas explicit Adams-Bashforth schemes (second and forth orders) were used in temporal advancement of velocities and sediment concentration fields. A new analytical formulation for settling velocity was obtained, while fortuitous re-suspension flux was applied like a boundary condition in the channel bottom. The computational code was totally developed in this work. The results of present simulations show that large-eddy simulation coupled to the immersed boundary method, considering, yet, the settling velocity of particles and the advection-diffusion equation for mass transport, constitute potential tools for sediment transport evaluation in water flows.

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Penha, Felipe Campos. "Efeitos de canais inelásticos no transporte eletrônico: um exemplo além do formalismo de Landauer." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/76/76131/tde-19032013-082632/.

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Neste trabalho, estudamos a influência de canais de espalhamento inelástico no transporte eletrônico. Primeiramente, expomos o formalismo de Landauer usual para o cálculo da corrente elétrica em sistemas em que o espalhamento é puramente elástico. Como exemplo, calculamos a corrente para um potencial delta de Dirac a partir de suas probabilidades de transmissão. A amostra correspondente é aquela de uma camada muito fina com impurezas (não-magnéticas) contida em uma heterostrutura semicondutora. Mostramos que a distorção do potencial quântico devido à voltagem aplicada pode ser desprezada no cálculo da corrente elétrica, abaixo da energia de Fermi do emissor. Subsequentemente, acoplamos o potencial delta a um oscilador harmônico quântico para modelar a presença de fônons no sistema. Encontramos modos inelásticos de transmissão que se tornam acessíveis para energias cada vez maiores, múltiplas do quantum hω. Devido à conservação de probabilidade, a abertura de cada novo canal corresponde a bicos\" nas probabilidades de transmissão dos modos abaixo deste, em função da energia de incidência do elétron. No caso de uma delta atrativa, ressonâncias assimétricas com perfil de Fano são observadas. Adaptamos o formalismo de Landauer, incluindo canais inelásticos independentes. Seguindo um trabalho anterior de Emberly e Kirczenow (2000), mostramos que existe uma forma de se levar em conta possíveis coincidências nos estados de espalhamento finais aplicando o princípio de exclusão de Pauli. Isto leva as distribuições dos estados de espalhamento a estarem fora de equilíbrio, já que dependem umas das outras. Resolvendo o problema auto-consistentemente, somos capazes de obter a corrente elétrica a partir das probabilidades de transmissão do potencial quântico. Nossos resultados demonstram que as ressonâncias de Fano do potencial atrativo dão origem a uma diminuição da inclinação da corrente elétrica contra a voltagem aplicada, já que elétrons são presos\" ao potencial por um tempo infinito. Mostramos este efeito num regime de voltagens baixas em comparação com a energia de Fermi, para o qual desprezamos a distorção do potencial quântico devido à voltagem aplicada. Além disso, uma comparação com os resultados do formalismo de Landauer mostra que uma discrepância significativa é observada para o caso de o oscilador estar inicialmente excitado e fortemente acoplado ao elétron.
In this work, we study the influence of inelastic scattering channels in electronic transport. We first present the usual Landauer formalism, for calculating the electric current in systems where the scattering is purely elastic. As an example, we calculate the current for a Dirac delta potential from its transmission probabilities. The corresponding sample is that of a very thin layer with (non-magnetic) impurities within a semiconductor heterostructure. We show that the distortion of the quantum potential due to the applied voltage can be ignored in the calculation of an electric current below the Fermi energy of the emitter. Then we couple the delta potential to a quantum harmonic oscillator to model the presence of phonons in the system. We find inelastic transmission modes that become available for increasing energies, multiple of the quantum hω. Due to conservation of probability, the opening of each new channel corresponds to kinks\" in the transmission probabilities of lower modes as a function of the energy of the impinging electrons. In the case of an attractive delta potential, asymmetric resonances with a Fano-like profile are observed. We adapt the Landauer formalism by including the independent inelastic channels. Following a previous work by Emberly and Kirczenow (2000), we show that there is a way to take into account the possible coincidences in the final scattering states using Pauli\'s exclusion principle. This causes the distributions of the scattering states to be out of equilibrium, as they depend on each other. Solving the problem self-consistently, we are able to obtain the electric current from the transmission probabilities of the quantum potential. Our results demonstrate that the Fano resonances of the attractive potential gives rise to a decrease of the slope in the electric current versus the applied voltage, as the electrons are trapped\" in the potential for a finite amount of time. We have shown this effect in a low voltage regime with respect to the Fermi energy, for which we ignore the distortion of the quantum potential due to the applied voltage. Furthermore, a comparison with the results from the Landauer formalism shows that a significant discrepancy is seen for the oscillator initially in its excited mode and strongly coupled to the electron.

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Ruy, Fernando. "Estudo da bioenergetica mitocondrial de leveduras de importancia patologica : determinação da contribuição das diferentes vias de transporte de eletrons para o crescimento celular." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313796.

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Orientador: Alicia Juliana Kowaltowski
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: A levedura Candida albicans é um importante patógeno em humanos. A principal característica deste microorganismo é a sua habilidade de sobreviver em diferentes ambientes do hospedeiro, com diferentes tensões de oxigênio. Acredita-se que esta flexibilidade deve-se à expressão de vias alternativas de redução do oxigênio e ao controle do fluxo de elétrons entre elas e a cadeia respiratória clássica. A presença destas vias pode ainda estar relacionada à alta resistência do fungo a drogas, uma vez que a inibição de uma delas pode ser suprida pela atividade das outras. Neste sentido, um entendimento detalhado do transporte de elétrons destas leveduras torna-se imprescindível. Neste trabalho, após a confirmação da existência de três vias de transporte de elétrons nas mitocôndrias de C. albicans: a cadeia clássica (CRC), uma via paralela (PAR) e a oxidase alternativa (AOX), avaliou-se a importância de cada uma delas para o crescimento celular. Assim, foram feitos tratamentos com compostos que possuem efeito inibitório sobre pontos específicos a cadeia respiratória da levedura, e avaliações de curvas de crescimento dos organismos. A antimicina e o KCN, que inibem os Complexos III e IV da CRC, respectivamente, preveniram totalmente o crescimento quando comparadas à cultura controle. O BHAM, um inibidor da AOX, também promoveu a inibição da proliferação celular. A presença de rotenona, um inibidor do Complexo I da CRC, não inibiu completamente o crescimento da levedura. Estes experimentos foram então correlacionados com medidas de consumo de oxigênio nas suspensões mitocondrial e celular, onde nós observamos que a rotenona e o BHAM foram capazes de promover apenas inibições parciais da respiração. As concentrações de antimicina e KCN que promoveram inibições respiratórias parciais proporcionaram efeitos distintos sobre o crescimento. Enquanto a antimicina preveniu totalmente o crescimento, o KCN não apresentou efeito inibitório. Avaliamos ainda os níveis de espécies reativas de oxigênio (EROs) e glutationa oxidada (GSSG) nas células incubadas na presença dos inibidores respiratórios. Os níveis de EROs nas mitocôndrias tratadas com antimicina foram significativamente aumentados em relação aos outros grupos. Observamos também um aumento de GSSG nas células incubadas com antimicina e BHAM. Nossas descobertas experimentais sugerem que as inibições do Complexo III da CRC e a AOX previnem o crescimento da levedura por promover estresse oxidativo de origem mitocondrial
Abstract: Candida albicans is an important pathogen in humans. A crucial feature of this microorganism is its ability to survive in different environments within the host with distinct oxygen tensions. It is believed that this flexibility is due the expression of alternative oxygen reduction pathways and the control of electron flux between them and the classical respiratory chain. The presence of these pathways may also be related to the high resistance these fungi present to drugs, since the inhibition of one electron transport pathway can be compensated by the activity of the others. In this study we confirm the presence of three electron transport pathways in Candida albicans: the classical respiratory chain (CRC), a parallel chain (PAR) and an alternative oxidase (AOX). We also evaluated the contribution of each pathway toward yeast growth. To do so, we measured cellular proliferation in the absence and presence of electron transport inhibitors. Antimycin A and KCN, which inhibit Complexes III and IV, respectively, totally prevented cellular growth. BHAM, an AOX inhibitor, also promoted inhibition of yeast growth. Surprisingly, the presence of rotenone, an inhibitor of respiratory Complex I, inhibited yeast growth only partially. These results were then correlated with oxygen uptake in mitochondrial and cell suspensions, which revealed that rotenone and BHAM promote only partial respiratory inhibitions. Concentrations of antimycin and KCN which promoted partial respiratory inhibition had distinct effects on growth. While antimycin totally prevented cell proliferation, KCN did not. We also evaluated the levels of reactive species of oxygen (ROS) and oxidized glutathione in the cells incubated in the presence of respiratory inhibitors. The levels of ROS in antimycin-treated cells were significantly higher than in the other groups. Finally, we observed an increase of oxidized glutathione in cells incubated in the presence of antimycin and BHAM. These experimental findings suggest that inhibitions of complex III of the CRC and AOX prevent Candida albicans growth by promoting oxidative stress, indicating the importance of these pathways to ensure yeast viability
Doutorado
Ciencias Biomedicas
Doutor em Ciências Médicas

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39

Lande, Richard Jonathan. "The impact of deregulation in the transport sector in the United States on the Canadian transport industry." Thesis, University of Bath, 1991. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760621.

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40

Toniati, André Luis. "Escoamentos pulsantes com superfície livre : caracterização e sua ação em fundo de canais /." Ilha Solteira, 2018. http://hdl.handle.net/11449/155857.

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Orientador: Geraldo de Freitas Maciel
Resumo: No contexto de Desastres "Naturais", as corridas de lama têm sido objeto de estudo devido ao seu poder erosivo e, muitas vezes, destrutivo, acarretando perdas materiais vultosas e ceifando vidas. Nestes escoamentos, quando em condições favoráveis de vazão, inclinação e reologia do fluido, podem surgir instabilidades que se propagam em forma de trem de ondas na superfície, denominadas roll waves. A literatura acerca do assunto trata, geralmente, dos critérios de geração, estabilidade, e determinação das características principais do fenômeno, como amplitude, comprimento e celeridade de onda. Nesta dissertação buscou-se estudar a tensão de cisalhamento no fundo na presença de roll waves, em duas vertentes: a primeira apresenta as roll waves em água limpa, baseando-se no trabalho clássico de Dressler (1949); a segunda, dando continuidade aos trabalhos do Grupo de Pesquisa de Reologia de Materiais Viscosos e Viscoplástcos (Grupo RMVP), focou no estudo de roll waves desenvolvendo-se em fluidos do tipo Herschel-Bulkley, em duas situações - canal de fundo impermeável e fundo com condição de permeabilidade, grande contribuição desta dissertação. Os modelos matemáticos foram desenvolvidos com base nas equações de águas rasas, cuja implementação numérica permitiu confrontar resultados experimentais e numéricos, que apresentaram boa aderência. Para o modelo com condição de permeabilidade no fundo, verificou-se a influência do fator de porosidade nas características das roll waves (ampli... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Mudflows have been the focus of studies because of their erosive ability and often destructive power, causing material losses and taking away lives. Under favorable conditions of discharge, slope, disturbance, and rheology, these flows can develop a specific type of instability that is propagated downstream as shock waves, called roll waves. Most of the roll waves literature provides information on generation criteria, stability, and information of amplitudes, wavelengths, and celerity. This works brings a study of bottom shear stress in pulsating flows (roll waves) in 2 parts. In the first part, we present roll waves in clean water, based on Dressler’s work. In the second part, we continue the works of research team about roll waves developing in Herschel-Bulkley fluid under 2 conditions: impermeable bottom and porous bed. The mathematical models developed were based on shallow water equations. The results of these models were compared to Fluent and experimental results, showing a good agreement. For the mathematical model with porous bed condition, we evaluated the effect of porosity factor in properties of roll waves, and we observed that the amplitude of the roll wave usually increases, whereas the length and the celerity decrease with the presence of this factor. Finally, considering an impermeable bottom, the bottom shear stress presented an increase of 12% to 27%, depending on nature (laminar-turbulent) and dynamics (Froude number) of flow. Taking in account a porous b... (Complete abstract click electronic access below)
Mestre

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Hackmann, Cristiano Lima. "Modelos matemáticos para o transporte de íons por canais em membranas de axônicos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/10484.

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Esta dissertação apresenta uma revisão sobre canais iônicos com respeito aos seus aspectos biofísicos e sobre alguns modelos matemáticos utilizados em sua análise. As abordagens dividem-se em duas classes: uma em que é possível realizar análises exatas e outra mais apropriada à análise numérica. Será revista a solução da equação de Poisson em coordenandas toroidais, que fornece uma expressão para o potencial elétrico na região do canal. Uma outra abordagem estudada utiliza os ensembles da mecânica estatística de equilíbrio para determinar a forma do potencial elétrico médio nessa mesma região. As descrições destinadas à análise numérica compreendem: uma formulação em que todos os elementos são considerados como meios contínuos; a Dinâmica Browniana e a Dinâmica Molecular. A dissertação é encerrada com a apresentação de alguns resultados experimentais sobre canais reais. Ao final, o leitor deverá ter um panorama sobre os estudos, teóricos e aplicados, no campo da condução passiva de íons através de membranas celulares. Esta dissertação não tem por finalidade esgotar os tópicos que abrangem esta área do conhecimento.
This dissertation presents a review about ion channels with respect to their biophysical aspects and some mathematical models employed in its analysis. Our approach is separated in two parts: one where it is possible to achieve exact results and another more suitable to numerical analysis. There will be reviewed a solution for Poisson’s equation in toroidal coordinates which gives an expression for electrical potential in the region of the channel. Also, There will be reviewed the mean force potential formulation derived from the ensembles of equilibrium statistical mechanics. The numerical analysis approach comprehends formulations where all elements are considered as a continuum media and via Brownian Dynamics and the Molecular Dynamics. This dissertation finishes with a discussion of some experimental results about real channels. At the end of this all, the reader should have an overview about the studies, both theoretical and applied, in the field of passive conduction of ions through cell membranes. However, this dissertation has no intention to be a comprehensive review of the subject.

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Fila, Marc. "Transport du sodium et du potassium dans le canal collecteur cortical dans le syndrome néphrotique." Paris 6, 2013. http://www.theses.fr/2013PA066517.

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Le syndrome néphrotique défini par l’association d’une protéinurie massive et d’une hypoalbuminémie s’associe à une rétention hydro-sodée responsable de la constitution d’un syndrome oedémato-ascitique. Cette rétention hydro-sodée est une conséquence de la dysrégulation du transport de sodium au niveau de la cellule principale du canal collecteur cortical (CCD) avec une augmentation de l’activité de la pompe Na/K ATPase basolatérale. Classiquement, l’augmentation de la réabsorption de sodium dans le CCD est médiée par l’aldostérone, par le canal sodium épithélial ENaC et a comme résultante une augmentation de l’excrétion de potassium médiée par le canal ROMK. Cependant, des travaux préalables ont permis de montrer qu’au cours du syndrome néphrotique, la rétention de sodium était indépendante du système rénine angiotensine aldostérone (SRAA) et du canal ENaC. Le présent travail se décompose en 2 parties, la première consistant en l’étude de l’excrétion de potassium dans le CCD au cours du syndrome néphrotique, ayant permis de mettre en évidence une down régulation de ROMK induite par la présence pathologique d’albumine au niveau luminal et médiée par la voie de signalisation ERK/P-ERK. La seconde partie de ce travail, concernant le transport de sodium au cours du syndrome néphrotique, a permis de mettre en évidence un nouveau transporteur de sodium, ASIC2, dans le CCD indépendant du SRAA. Ce canal a des propriétés biophysiques et pharmacologiques propres différentes du canal ENaC ayant permis sa caractérisation fonctionnelle. L’expression d’ASIC au niveau rénal n’a, à ce jour, jamais été rapportée et son expression semble spécifiquement liée au syndrome néphrotique
Nephrotic syndrome which is defined by a heavy proteinuria and hypoalbuminemia, features a severe sodium retention which is implicated in ascites and edema formation. Sodium retention is a consequence of a dysregulation of sodium transport in the cortical collecting duct (CCD) with an increase activity of the basolateral Na,K ATPase pump. Traditionally, sodium absorption in the CCD is regulated by renin angiotensin aldosterone systeme (RAAS) with an implication of apical sodium channel ENaC and potassium apical channel ROMK. Previous works highlighted that, in nephrotic syndrome, sodium absorption was independent of RAAS and that ENaC was not implicated. The present work contains two distincts parts: the first one is a study of potassium excretion in the CCD in the nephrotic syndrome. It highlighted that nephrotic animals showed a down regulation of potassium channel ROMK induced by luminal albumin that activated ERK pathway. The second part, a study of sodium transport in the CCD in the nephrotic syndrome highlighted a new sodium channel independent of RAAS system and sensitive to amiloride: ASIC2 implicated in sodium absorption in the CCD. This channel exhibits some specific biophysic and pharmacologic properties different from ENaC. To our knowledge, it’s the first time that expression of an ASIC family channel was reported in the kidney

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Song, Wei. "Modeling bilateral air services agreement for the purpose of measuring the economic effects of air transport liberalization : a case study of Canada and China." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/24157.

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International air services are mostly regulated by bilateral Air Services Agreements (ASAs) signed by each pair of countries. Most of the bilateral ASAs are still operated within the framework of the Chicago Convention, and considered to be restrictive and inefficient to serve international air markets. Over the last two decades, the United States, European Union, and some other countries have pioneered liberalization of bilateral ASAs and received remarkable positive results. Although Canadian government released a “Blue Sky” policy in 2006 to pursue negotiation of Open Skies-type agreements, many of the major air markets, such as the Canada—China market, are still regulated by restricted ASAs. Whether or not to liberalize bilateral ASAs and what are the impacts of liberalization has become an interest to airlines, investors, consumers and regulators. However, the existing studies are insufficient for understanding the magnitudes of potential impacts of such liberalization, and, hence, to provide direct insights to policy makers. Therefore, there is a need for a new study for simulating potential economic effects of ASA liberalization. The primary objective of this thesis is to develop a computable model to estimate potential economic effects of bilateral ASA liberalization between Canada and China. In particular, this study aims to estimate how the market shares of the flag carriers would change and how the gains and losses would be changed among passengers and carriers in either country. To address these objectives, we compare the simulation results between the base case (2006 data without liberalization) and the case of liberalizing Canada-China ASA to a varying degree in order to estimate the impacts of the liberalization. The major findings are: (a) airfare would decrease with air liberalization, which would stimulate more passengers, and induce airlines to increase flight frequency. ; (b) in most of the cases, passengers carried by incumbent carriers would increase even if new airlines enter the routes; (c) although carriers’ profit would decrease, the aggregate economic welfare would increase because consumer benefits would increase dramatically; and (d) while any level of air liberalization would be positive, Open Skies would have the greatest impacts on both countries.

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Stieglitz, John Dommerich. "Optimizing Transport of Live Juvenile Cobia (Rachycentron canadum): Effects of Salinity and Shipping Biomass." Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_theses/21.

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Live juvenile cobia (Rachycentron canadum) transport methods were examined to determine opportunities for increasing packing density in closed containers for temporal durations up to 24 hours. Juvenile cobia (27 to 46 days-post-hatch (dph)) were tested for salinity tolerance following abrupt transfer from 35 ppt salinity water to salinities ranging from 0 ppt to 55 ppt. Results indicate a wide range of tolerance, with 100% survival at 24 hours post-transfer in salinities between 11 ppt and 45 ppt. Salinity preference was also tested to determine a possible correlation between acclimation salinity and salinity preference using an experimental horizontal salinity gradient with juvenile cobia (87 dph) over a period of 24 hours. Results of the salinity preference trials showed that salinity preference was directly related to acclimation salinity. Using two different salinities within the range tested in the tolerance trials (12 ppt and 32 ppt), a 24 hour simulated shipping trial was conducted comparing final survival between the two salinities at each of four packing densities (5 kg/m3, 10 kg/m3, 15 kg/m3, and 20 kg/m3). Results indicated a significant relationship between salinity and stocking density on survival of juvenile cobia following a 24 hour simulated shipment. At packing densities above 10 kg/m3, survival was significantly higher in the low salinity (12 ppt) treatments as compared to survival rates in the higher salinity (32 ppt) treatments. To help aquaculture professionals make accurate and economical decisions regarding the shipment of live juvenile cobia in closed containers, a bioeconomic model was constructed using survival data at different packing densities (1 kg/m3 to 20 kg/m3) and salinities (12 ppt and 32 ppt) obtained in the experimental trials combined with shipping cost and fingerling price data. The resulting model enables cobia fingerling producers to optimize their shipping methods and protocols, allowing for reductions in labor and material costs.

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Henninges, Jan. "Thermal properties of gas hydrate bearing sediments and effects of phase transitions on the transport of heat deduced from temperature logging at Mallik, NWT, Canada." Potsdam : GeoForschungsZentrum Potsdam, 2005. http://www.gfz-potsdam.de/bib/zbstr.htm.

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Saayman, Maryna. "Characterisation of the malate transporter and malic enzyme from Candida utilis." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/16520.

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Dissertation (PhD)--University of Stellenbosch, 2005.
ENGLISH ABSTRACT: Yeast species differ remarkably in their ability to degrade extracellular dicarboxylic acids and to utilise them as their only source of carbon. The fission yeast Schizosaccharomyces pombe effectively degrades L-malate, but only in the presence of an assimilable carbon source. In contrast, the yeast Saccharomyces cerevisiae is unable to effectively degrade L-malate, which is ascribed to the slow uptake of L-malate by diffusion. In contrast, the yeast Candida utilis can utilise L-malate as the only source of carbon and energy, but this is subject to substrate induction and catabolite repression. Very little research has been done on a molecular level in C. utilis and only a few of its genes have been studied. In this study, we have shown that the yeast C. utilis effectively degraded extracellular L-malate and fumarate, but in the presence of glucose or other assimilable carbon sources, the transport and degradation of these dicarboxylic acids was repressed. The transport of both dicarboxylic acids was shown to be strongly inducible by either L-malate or fumarate and kinetic studies suggest that the same transporter protein transports the two dicarboxylic acids. In contrast, S. pombe effectively degraded extracellular L-malate, but not fumarate, only in the presence of glucose or other assimilable carbon sources. The S. pombe malate transporter was unable to transport fumarate, although fumarate inhibited the uptake of L-malate. In order to clone the C. utilis dicarboxylic acid transporter, a cDNA library from C. utilis was constructed using a number of strategies to ensure representativeness and high transformation frequencies. The cDNA library was transformed in a S. cerevisiae strain carrying a plasmid containing the S. pombe malic enzyme gene (mae2) to allow screening for a malate-degrading S. cerevisiae clone. However, no positive clones that would indicate the successful cloning of the C. utilis malate transporter were obtained. The C. utilis malic enzyme gene, CuME, was subsequently isolated from the cDNA library based on conserved sequence homologies with the genes of S. cerevisiae and S. pombe, and characterised on a molecular and biochemical level. Sequence analysis revealed an open reading frame of 1926 bp, encoding a 641 amino acid polypeptide with a predicted molecular weight of 70.2 kDa. The optimum temperature for the C. utilis malic enzyme was 52°C and the enzyme was stable at 50°C for 2 hours. The inferred amino acid sequence showed significant homology with the malic enzymes of S. pombe and S. cerevisiae. Expression of the CuME gene is subject to glucose repression and substrate induction, as was observed for the dicarboxylic acid transporter from C. utilis. The CuME gene was successfully coexpressed with the S. pombe malate permease gene (mae1), resulting in a recombinant strain of S. cerevisiae able to effectively degrade L-malate.
AFRIKAANSE OPSOMMING: Daar is ’n merkwaardige verskil in die vermoë van verskillende gisspesies om ektrasellulêre dikarboksielsure af te breek en dit as enigste bron van koolstof te benut. Die splitsingsgis Schizosaccharomyces pombe kan L-malaat effektief afbreek, maar slegs in die teenwoordigheid van ’n ander benutbare koolstofbron. In teenstelling hiermee is dit vir die gis Saccharomyces cerevisiae onmoontlik om L-malaat effektief af te breek en te benut, wat hoofsaaklik toegeskryf kan word aan die stadige opname van L-malaat deur middel van diffusie. Die gis Candida utilis kan egter L-malaat as die enigste bron van koolstof en energie benut, maar dit is onderhewig aan substraat-induksie en kataboliet onderdrukking. Baie min navorsing op molekulêre vlak is tot hede in C. utilis uitgevoer en slegs ’n paar gene in hierdie gis is al bestudeer. In hierdie studie het ons aangetoon dat die gis C. utilis L-malaat en fumaraat effektief afbreek, maar dat glukose of ander benutbare koolstofbronne die opname en afbraak van hierdie dikarboksielsure onderdruk. Die opname van beide dikarboksielsure is sterk induseerbaar deur L-malaat óf fumaraat, terwyl kinetiese studies toon dat beide dikarboksielsure deur dieselfde transporter-proteïen vervoer word. In teenstelling hiermee kan S. pombe ekstrasellulêre L-malaat, maar nie fumaraat nie, in die teenwoordigheid van glukose of ’n ander benutbare koolstofbron effektief afbreek. Die S. pombe L-malaat transporter was nie in staat om fumaraat te vervoer nie, alhoewel fumaraat die opname van L-malaat onderdruk het. Ten einde die dikarboksielsuur transporter van C. utilis te kloneer, is verskeie strategieë gevolg ten einde ’n cDNA-biblioteek van C. utilis te konstrueer wat verteenwoordiging en hoë transformasie-frekwensies kan verseker. Die cDNA-biblioteek is getransformeer in ’n S. cerevisiae ras wat die S. pombe malaatensiem geen (mae2) bevat om die sifting van ’n S. cerevisiae kloon wat malaat effektief kan afbreek, moontlik te maak. Geen positiewe klone wat dui op die klonering van die C. utilis malaat transporter kon egter gevind word nie. Die C. utilis malaatensiem geen, CuME, is vervolgens van uit die cDNA biblioteek geïsoleer deur van gekonserveerde DNA-homologie met S. cerevisiae en S. pombe gebruik te maak, en op molekulêre en biochemiese vlak gekarakteriseer. DNA-volgordebepaling het ’n oopleesraam van 1926 bp onthul, wat kodeer vir ’n 641 aminosuur polipeptied met ’n verwagte molekulêre gewig van 70.2 kDa. Die optimale temperatuur van die C. utilis malaatensiem was 52°C en die ensiem was vir 2 ure stabiel by 50°C. Die afgeleide aminosuurvolgorde het beduidende homologie met die malaatensieme van S. pombe en S. cerevisiae getoon. Die CuME geen is suksesvol saam met die S. pombe malaat permease geen (mae1) uitgedruk om ’n rekombinante S. cerevisiae ras te genereer wat in staat is om L-malaat effektief af te breek.

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Trueb, Oliver Ernst Friedrich. "Transport on waterways in the Pearl River Delta : final report /." Thesis, Hong Kong : University of Hong Kong, 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17592355.

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Swiecicki, Ewa. "Legal aspects of licensing of airline transport pilots : international standards versus Canadian aviation safety regulations." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61155.

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The laws and regulations governing certification of aviation personnel constitute one of the essential elements of aviation legislation. They have a significant effect upon the global safety of the civil air transportation system.
This dissertation aims at describing the existing regulations in the field of pilot licensing. Its scope is narrowed down to the highest category of licence applicable to professional pilots and known as the airline transport pilot licence. The thesis depicts and analyses the process of creation and the contents of licensing standards and recommended practices as developed by various ICAO bodies and incorporated in Annex 1 to the Chicago Convention.
The survey of pilot licensing system currently in force in Canada provides the example of domestic legislation applicable in this respect. It is performed with the aim of exploring the compatibility of Canadian law with the global legal requirements as prescribed in Annex 1 and other supporting ICAO documentation.

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Silva, Eduardo Teixeira da. "Solo-cimento e solo-vinhaça no revestimento de canais de irrigação para transporte de vinhaça : adequação fisica e parametros hidraulico." [s.n.], 1992. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257350.

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Orientador : Wesley Jorge Freire
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
Made available in DSpace on 2018-07-18T15:43:41Z (GMT). No. of bitstreams: 1 Silva_EduardoTeixeirada_M.pdf: 3618048 bytes, checksum: 9d364f20a56a7fd219638f3a919c58bd (MD5) Previous issue date: 1992
Mestrado
Construções Rurais e Ambiencia
Mestre em Engenharia Agrícola

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Benistant, Christophe. "Transport plasmatique et cellulaire des acides gras chez les oiseaux développant une thermogenèse sans frisson : étude comparée chez le caneton de Barbarie acclimaté au froid et le poussin de manchot royal en conditions naturelles." Lyon 1, 1997. http://www.theses.fr/1997LYO10308.

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Ce travail decrit les relations existant entre le transport plasmatique et cellulaire des acides gras (ag) et les importantes capacites de thermogenese des canetons acclimates au froid et des poussins de manchot royal adaptes au froid. Chez les deux especes, l'etude des lipides et des lipoproteines plasmatiques ainsi que des lipases endotheliales suggere que l'exposition au froid augmente l'apport cellulaire des ag au muscle squelettique et au foie. La quantification des fatty acid-binding proteins et la capacite de liaison des ag aux proteines cytoplasmiques suggerent que les capacites de transport intracellulaire des ag sont stimulees dans le muscle et le foie des oiseaux exposes au froid. Chez les manchots, le jeune naturel de longue duree au froid preserve les capacites de transport des ag dans le muscle et le foie. En conclusion, les mecanismes musculaires et hepatiques de transport des ag contribueraient a favoriser les capacites de thermogenese des oiseaux exposes au froid, nourris ou soumis a un jeune de longue duree.

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Dissertations / Theses on the topic 'Canada. Transports Canada'

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