McGill University Thèses et mémoires par auteur commençant par F

L'amélioration des propriétés mécaniques des aciers faiblement alliés est la résultante d'un affinement de la taille des grains couplé à une quantité controllée de précipités cohérents. Une faible déformation plastique de la ferrite, Cool Deformation, à basse température, augmente la force et la résistance de l'alliage, conditionnellement au contrôle de la taille des grains. L'explication retenue face à ce phénomène est l'augmentation de l'homogénéisation des précipités, mis de pair avec la diminution de leur taille. . Dans le présent travail, les effets du niobium et du cuivre sur les propriétés mécaniques et microstructures d'acier laminés à divers degrés ont été …  Lire la suite

Les nouvelles technologies demandent des réseaux optiques flexibles. Les commutateurs optiques offrent une capacité de transmission efficace et utile pour ces applications. La large bande passante et le faible voltage de modulation sont les avantages des commutateurs optiques en espace. L'objectif de cette recherche est d'optimiser le profil de dopage dans le guide afin de maximiser l'effet d'électro-optique tout en minimisant les pertes optiques. Les guides d'ondes semi-conducteurs à hétérostructure double ont été utilisés pour les appareils de commutation optique. La meilleure combinaison du ratio d'extinction, d'efficacité de puissance et des dimensions globales des commutateurs a été trouvée dans un …  Lire la suite

Precise material architectures and interfaces can generate attractive properties in materials. For example, Topologically Interlocked Materials (TIMs) are architectures that can turn brittle materials like ceramics into tough, deformable and impact-resistant material systems. This strategy has been adapted from biological materials such as nacre and tooth enamel, which have been in nature for millions of years. There are, however, some challenges in the mimicking of the biological materials and the production of TIMs. Designing TIMs for thermomechanical applications require in-depth thermomechanical finite element modelling (FEM). All possible architectures in the vast design space, containing many potential structures and configurations arranged …  Lire la suite

Grimard, Franque (Supervisor1)  Lire la suite

Les valeurs et les comportements prosociaux sont de plus en plus importants dans le choix des produits par les consommateurs. Les consommateurs, quant à eux, sont davantage préoccupés par les conséquences des produits sur d’autres personnes dans la société et sur l’environnement. Par le biais de deux articles, cette thèse examine l’impact des comportements prosociaux des entreprises sur la préférence pour certains produits à travers une évaluation des conséquences à long terme et à court terme. Le premier article examine l’impact de la prépondérance du comportement prosocial des entreprises sur la maîtrise de soi. Les résultats de cinq études montrent …  Lire la suite

Le régulateur de la conductance transmembranaire de la fibrose kystique (CFTR) est une protéine transmembranaire qui agit comme un canal sur la membrane apicale de l'épithélium et qui est codée par le gène CFTR. Le rôle physiologique exact de CFTR reste incertain. Cependant, la mutation de ce gène provoque un mauvais repliement du CFTR, et la protéine mutante est retenue dans le réticulum endoplasmique, empêchant son trafic vers le Golgi et la membrane plasmique. Plus précisément, la mutation la plus commune est la délétion d'un résidu phénylalanine en position 508 dans la protéine CFTR (CFTRΔF508), qui conduit à la maladie …  Lire la suite

The Crk adaptor proteins (CrkI, CrkII and CrkL) play an important role during cellular signalling by mediating the formation of prote in complexes. We examined the function of Crk in cancer by examining how the loss of Crk would affect tumor progression using RNA interference, as well as examining the consequences of Crk overexpression. For each cancer cellline tested, loss of Crk expression corresponded with a significant decrease in cell migration, invasion, and adhesion, demonstrating that Crk adaptor proteins play an important role in integrating signaIs of highly malignant cancer cell lines. This has important implications as elevated levels of …  Lire la suite

Objectives: This thesis aimed to understand the perspectives of dentists towards the Montreal-Toulouse model, an approach that encompasses person-centeredness and social dentistry. More specifically, we wanted to know a) how dentists perceived the Montreal-Toulouse model; and b) how ready they were to adopt it.Methods: We conducted a qualitative descriptive study based on semi-structured interviews with a sample of dentists in the Province of Quebec, Canada. We employed a combination of maximum variation and snowball sampling strategies and recruited 14 information-rich dentists; these dentists were both working in private practice and as teachers in a dental faculty. The interviews were conducted …  Lire la suite

L’adoption rapide de l’apprentissage profond en imagerie médicale a révolutionné les flux de travail cliniques, tout en introduisant d’importants défis en matière de transparence, de biais et de fiabilité. Les méthodes classiques d’interprétabilité post-hoc—telles que les cartes de saillance—échouent souvent à révéler ou à corriger l’influence des corrélations fallacieuses et des raccourcis d’apprentissage, compromettant ainsi l’utilité clinique. Cette thèse aborde ces lacunes en développant de nouveaux cadres qui unifient l’explicabilité contre-factuelle, l’atténuation robuste des biais et le raisonnement agentique pour une intelligence artificielle médicale responsable et interactive.Premièrement, nous analysons les limitations des pipelines conventionnels de génération de contre-faits, en soulignant …  Lire la suite

This thesis investigates the Islamic response to modernization and its common dilemma as seen through the eyes of Nurcholish Madjid, one of the most influential and prominent Muslim thinkers in Indonesia today. He and his followers represent the most radical development in Indonesian Islamic religio-political discourse in recent decades. This study will survey the growth of his thought from his first involvement with the Islamic renewal movement in the early 1970s, or more precisely after the inception of the New Order era, until the mid-1990s. The movement that he has founded seeks to reformulate the positive nature of modernity and …  Lire la suite

La leucémie aiguë mégacaryoblastique (LAMK) est un sous-type de leucémie myéloïde aiguë (LMA) qui se caractérise par des mégacaryoblastes anormaux et une myélofibrose dans la moelle osseuse. La LAMK est rare et peut représenter jusqu'à ≈10 % des cas de LMA pédiatriques (<3 ans). Des gènes de fusion chimériques récurrents sont détectés et considérés comme les événements oncogéniques principaux de cette maladie,tels que CBFA2T3::GLIS2 (CG2), NUP98::KDM5A (N5A) et d’autres. Notre groupe a identifié une autre fusion NUP98 dans la LAMK, NUP98::BPTF (NTF). La LAMK est une leucémie associée à un taux de mortalité élevé (taux de guérison <40 %) et …  Lire la suite

Christianson Syndrome (CS) is a recently characterized X-linked neurodevelopmental disorder caused by loss-of-function mutations in the gene slc9a6, encoding the endosomal Na+/H+ Exchanger 6 (NHE6). The disorder is associated with developmental delay, intellectual disability, loss of motor coordination, mutism, ataxia, epilepsy, as well as autistic features. In addition to these symptoms, CS patients exhibit elevated pain thresholds to noxious stimuli as well as discomfort at normally innocuous stimuli. The underlying causes of these sensory deficits are yet to be determined. Hence, this study aims at understanding how loss-of-function of NHE6 affects transmission and processing of pain.To this end, we examined …  Lire la suite

Le cancer du sein est le cancer le plus fréquemment diagnostiqué et la deuxième cause de décès du cancer chez les femmes canadiennes. La caractéristique la plus morbide et mortelle de la maladie est la formation des métastases. La progression du cancer du sein est une conséquence de la perturbation de l'organisation cellulaire normale, de la polarité et de l'adhérence cellule à cellule, ce qui permet aux cellules d'être plus mobiles et invasives. La protéine kinase C atypique iota (aPKCἰ) agit comme un oncogène et se trouve en taux élevé dans l'adénocarcinome du poumon, la leucémie myéloïde chronique, les lignées …  Lire la suite

Oat is one of the major cereals that is grown worldwide for human food and animal feed. Its use in the human diet is becoming popular due to its ability to reduce serum cholesterol and glucose level. This has been attributed to its high β-glucan content. β-glucan is a major non-starch polysaccharide, consisting of double β-1,3 and β-1,4 linkages. Information about β-glucan synthesis in oat is lacking due to the availability of limited genomic resources. Recently, a Thaumatin Like Protein 8 (TLP8) has been identified in barley that interacts with β-glucan and regulates its grain content. We hypothesize that the …  Lire la suite

The necessity of modelling multibody systems with flexible links in high-speed operations and space structures has become apparent. In this thesis, a general formulation for the simulation of multibody systems with multiple kinematic loops and flexible links of arbitrary shapes is developed. Parallel manipulators, space structures, multi-armed manipulators, and cooperating serial manipulators are examples of these systems. Finite element method is used for discretization of the flexible links, while the Lagrange formulation is used to derive the equations of motion of the uncoupled links. The kinematic constraints equations are generated next by using the natural orthogonal complement (NOC) of the …  Lire la suite

The mechanical properties of cloth, glass fiber polyester composite at different temperatures are determined. The viscoe1astic properties of this material are characterized by using relaxation tests. The theoretical relationships are used in appropriate computer programs. This includes correction of the relaxation curves for the finite rise time of strain. The experimental effort covers studies on specimens tested at different temperatures (-40 to 400~) and strain levels (0.1 to 1.2 percent). The linear viscoelastic behavior is verified for each testing temperature. The relaxation data are plotted on double logarithmic paper, and the viscoelastic properties at very short and long time are …  Lire la suite

Self-renewal is central to the expansion of normal and cancerous stem cells. Its understanding is therefore critical for future advances in transplantation-based therapies and cancer treatment. Although the molecular machinery controlling stem cell self-renewal remains poorly defined, a number of genes important to this process have recently been identified. Two prominent genes in this group are Hoxb4 and Bmi1. Members of our group led the way to demonstrate important regulatory functions of these genes in hematopoietic stem cell (HSC) self-renewal and expansion. The major goal of my thesis project is to dissect mechanisms that regulate self-renewal of HSCs. Our starting …  Lire la suite

Many of the common mutations in cancer affect key metabolic signaling pathways. These mutations promote altered cellular metabolism (Hanahan and Weinberg, 2011). This change in metabolism, termed the "Warburg Effect" describes the phenomenon where many cancer cells preferentially use aerobic glycolysis for energy production, despite an adequate oxygen supply. This change in metabolism supplies both the necessary energy and biosynthetic intermediates for proliferation, and confers a selective growth advantage for cancer cells. AMP-activated protein kinase (AMPK) is an evolutionarily conserved central regulator of cellular metabolism and energy homeostasis. Under conditions of energetic stress, AMPK is activated by its upstream kinase …  Lire la suite

Employant une théorie de l’action sociale ancrée dans la pratique et proposant un cadre théorique original inspiré de l’endosymbiose ainsi que d’un mécanisme de délimitation et de contestation des frontières communales, ce mémoire cherche à démontrer que la nature du « pouvoir international » n’est pas un attribut incontestable du système étatique, facile à identifier et à mesurer. Ce mémoire soutient plutôt que tout « pouvoir » est dynamique et contextuel, ce tant historiquement que socialement. Référant à la Grande-Bretagne des débuts de l’époque moderne comme étude de cas, ce mémoire identifie deux ruptures métathéoriques dans la science politique et …  Lire la suite

In light of the 2015 Truth and Reconciliation Commission’s final report and its calls to action in education, this research study sought to better understand whether non-Indigenous teacher participants were initially prepared by their respective post-secondary institutions on “how to integrate Indigenous knowledge and teaching methods in the classroom” (TRC, 2015, #62ii) in addressing the calls to action in education for reconciliation while attending teacher training. The researcher adopted a decolonized Indigenous methodology approach meant to resist the dominant western-style method of conducting research in a First Nations community in Québec, by honouring Indigenous cultural knowledge systems. Consequently, the researcher …  Lire la suite

Andre Pieyre de Mandiargues' Le musee noir is a collection of short stories insidiously permeated by the monster figure in its most diverse forms. Far from being reduced to a simple thematic function, this omnipresence of the monstrous contributes to making the collection truly a whole by instilling it with an internal mode of operation. This rhetoric of the monstrous directs both the collection and each of the stories, all the while driving their dynamic of the fantastic. The mandiarguian text acquires its fantastic dimension through a progressive transformation of the protagonist's point of view, inciting him to perceive his …  Lire la suite

The experimental research described in this thesis was undertaken by the writer to determine the efficiency of corduroy blanket and flotation concentration processes, followed by amalgamation of the two concentrates, in an attempt to develop a suitable method for recovering the gold in Lake Rowan ore. The work was carried on under the direction of Professor J. W. Bell of the Department of Mining and Metallurgy, McGill University. Acknowledgment is also made of assistance rendered by Professor G. Sproule and Mr. D. O'Shaughnessy. [...]  Lire la suite

Mostly known for its use in cancer care, radiotherapy is a treatment modality that uses ionizing radiation to kill malignant cells. This form of therapy requires careful planning that for nearly three decades has been based on computed tomography (CT) images, from which the position of tumours and healthy tissues can be determined. However, CT alone cannot always provide the contrast necessary to define targets. In these cases, the superior soft tissue contrast of magnetic resonance imaging (MRI) is used for more reliable contouring. Unfortunately, MRI alone is insufficient for treatment planning because CT images are also used to estimate …  Lire la suite

Optical multiaccess networks, and more specifically passive optical networks (PONS), can provide high bandwidth to the end user by extending the fiber into the local access network (fiber-to-the-home, -building, -curb). In a PON, multiple users share the fiber infrastructure in a point-to-multipoint (P2MP) network topology. This creates new challenges for the design of receiver front-ends and clock and data recovery circuits (CDRs). Moreover, the challenges depend on the multiple access method that is used to share the bandwidth among users. This thesis presents novel burst-mode CDR circuits for PONs and multiaccess networks. The two access methods considered are optical code …  Lire la suite

Parallel optical interconnects (POIs) promise to deliver tremendous gains in bandwidth for applications such as massively parallel computing systems and telecommunication switches. At the core of any interconnect solution lies the fundamental problem of reliable transmission. Next-generation optical communication designers are running into hard limits when it comes to increasing data transmission rates and reducing errors. These two factors are typically in opposing balance: minimize bit error rate (BER) and data rates suffer, increase transmission rates and data integrity is compromised. To answer these design challenges, this thesis proposes to use forward error correction (FEC) codes in an attempt to …  Lire la suite

Zaloha, Anne (Supervisor)  Lire la suite

This study examines the intersections of child language learning and disability. It took place in Quebec, Canada, and investigated attitudes regarding the importance of learning additional languages for children with special educational needs and disabilities (SEND) among children’s parents (n = 5) and teachers (n = 14). The study further looked at factors influencing these attitudes as well as the impact of these attitudes on parents’ language use at home and teachers’ practices in the classroom. Parents and teachers engaged in short online interviews ranging from 20 to 90 minutes. Through a process of transcription and thematic analysis (Braun & …  Lire la suite

Whoriskey, Fred (Advisor)  Lire la suite

The importance and widespread distribution of the 2-amino sugars has gradually been revealed in investigations during the last 70 years. They are now regarded as important components of a broad group of substances, being present in many compounds of diverse biological function, such as heparin, the bacterial polysaccharides, the polysaccharides of connective tissue and the structural polysaccharides which make up the exoskeleton of many invertebrates. The amino sugars do not normally occur in the freestate, but as compounds of substances of varying complexity.  Lire la suite

The objective of reinforcement learning is to find "good" actions in an environment where feedback is provided through a numerical reward, and the current state (i.e. sensory input) is assumed to be available at each time step. The notion of "good" is defined as maximizing the expected cumulative returns over time. Sometimes it is useful to construct models of the environment to aid in solving the problem. We investigate Dyna-style reinforcement learning, a powerful approach for problems where not much real data is available. The main idea is to supplement real trajectories with simulated ones sampled from a learned model …  Lire la suite

Beaudet, Alain (Supervisor)  Lire la suite

In his contribution to the volume entitled The Social and Political Ideas of Some Great Medieval Thinkers, A. J. Carlyle treats of the place of St. Augustine in the history of political thought. In general he regards Augustine as a typical representative of Patristic thought, and finds his significance in the history of political ideas to lie in his re-statement of the traditional view of the Stoics and the Christian Fathers. On only one point does Carlyle find Augustine differing from the Stoic-Patristic tradition. It is the question of the relation of the state to justice. Augustine had quoted Cicero's …  Lire la suite

The COVID-19 pandemic has disrupted tuberculosis (TB) services globally. Measuring the extent of these disruptions is critical to mitigate their impact and provide valuable information for TB program improvement, particularly in settings hard-hit by both COVID-19 and TB, such as Peru and India. The overall aim of this manuscript-based thesis was therefore to evaluate TB care and outcomes during the COVID-19 pandemic in Peru and India and compare them to pre-pandemic trends. In Manuscript 1, we introduced TB care cascades and outlined data gaps for constructing them. Care cascades are a representation of the proportion of people reaching key milestones …  Lire la suite

Seed production areas and seed consuming areas rarely coincide in this era of scientific agriculture and efficient transportation. That it is not necessary for the two to coincide is based on the premise that the performance of a plant is directly associated with its own genotype and not on conditions under which the seed was produced. McFadden (1963) has cast serious doubt on the validity of this premise with the discovery that the same variety of barley would produce different yields in the same yield trial if the seed were grown in different geographical locations. He found, for instance, that …  Lire la suite

Since the mid-1970s, the economic fortunes of youth have declined substantially and the transition to adulthood has lengthened. This dissertation evaluates the possibility that these trends are related, by evaluating the economic consequences of less-standard temporal organization of schooling and employment events, using Statistics Canada's Survey of Labour and Income Dynamics (SLID) and the Youth in Transition Survey (YITS). The first chapter outlines how and why the relationship between youth and the labour market has changed, for better and worse, using estimates of cumulative earnings. The second chapter evaluates the relationship between delays in the attainment of a post-secondary degree …  Lire la suite

The regulation of gene expression is driven primarily by transcription factors binding to short DNA sequences. Here three studies related to promoter cis-regulatory motif discovery in plant promoters are presented. In the first study, an exact discriminative seeding DNA motif discovery addressing key issues associated with popular DNA motif discovery algorithms is proposed. The Seeder algorithm outperforms popular motif discovery tools on biological benchmark data. In the second study, the algorithm is applied to the identification of cis-regulatory motifs in seed storage protein gene promoters. Known and new motifs are discovered. In the third study, groups of orthologous genes are …  Lire la suite

The control of B lymphocyte production in bone marrow is of central importance in maintaining a supply of new B cells for primary humoral immune responses throughout life, while its perturbation may underlie states of immunodeficiency, neoplasia and autoimmunity. Molecules expressed by developing B cells and stromal cells within bone marrow, as well as systemic factors, may all play key roles in regulating proliferation and survival of precursor B cells in bone marrow. Candidate regulatory molecules investigated in the present work include surrogate light chains (SL) of immunoglobulin (Ig) expressed intracellularly by precursor B cells before and during the synthesis …  Lire la suite

Cette étude cherche à situer le phénomène de la radiodiffusion directe par satellites dans son contexte pertinent en ce qui concerne le Québec. A partir de l'intense débat international auquel elle donne lieu, l'auteur expose les caractéristiques et les perspectives de développement de cette technologie encore pré-opérationnelle, avant d'en discuter les implications en droit international et de proposer une solution possible à l'impasse des discussions juridiques aux Nations Unies. Le droit interne applicable est ensuite étudié par le biais des aspects constitutionnels des communications au Canada, analyses tant au niveau du texte de l'Acte de l'Amérique du Nord britannique que …  Lire la suite

Dans le monde occidental, la Seconde Guerre Mondiale est connue surtout pour les victoires mythiques des Alliés ou pour la destruction de l'Europe causé par les Nazis. Dans les premières années de la guerre, cependant, la victoire ne pouvait pas être pris pour acquis. En Grande-Bretagne et en France—divisé entre zone occupée, zone "libre" de Vichy, et le gouvernement en exile des Forces Françaises Libres—les citoyens ordinaires se concentraient sur la préservation de la famille nucléaire. Cet effort était lié à l'espoir d'une victoire. Cette thèse porte sur le traitement littéraire de la famille, de la sexualité et du genre …  Lire la suite

In Peru, exclusive breastfeeding (EBF) before six months of age decreased in urban areas (from 64.5% in 2007 to 59.9% in 2010) and the coastal region (from 60.1% in 2007 to 52.8% in 2010) despite a national infant feeding policy to protect, promote and support breastfeeding (BF). Health care providers (HCP) play an essential role in influencing mothers' feeding decisions. This study examined infant feeding promotion and support provided by government health services in Lima. Semi-structured interviews were conducted with 16 HCP and 11 mothers of infants < 6 months of age. Seven mothers participated in two focus group discussions. …  Lire la suite

Representatives of five arbovirus taxons (alphavirus, flavivirus, bunyavirus, rhabdovirus and orbivirus) and Hepatitis B core antigen were studied by immune electron microscopy (IEM) in an attempt to determine the suitability of IEM for the study of antigenic relationships among viruses, for rapid identification of virus unknowns and for antibody detection. Arbovirus antigens were used to titrate hyperimmune mouse ascitic fluids and guinea pig sera. With the exception of the orbiviruses, specific clumping was observed for all homologous systems studied. Studies by IEM confirmed the antigenic relationships between arboviruses which had previously been demonstrated by other serological tests. Alphavirus unknowns were …  Lire la suite