McGill University Thèses et mémoires par auteur commençant par F

Les dynamiques des capsules, des particules colloïdales de silice enrobées de films de multicouches de polymères et de leurs complexes analogues ont été quantifiées par résonance magnétique nucléaire (RMN) solide. Les suspensions aqueuses de complexes, les multicouches déposées sur les colloïdes de silice, et les capsules de polyélectrolytes ont été analysées par RMN 2H en fonction du nombre de couches, de la température et de la force ionique. Il a été démontré que le mouvement du squelette des polyélectrolytes est plus rapide lorsque les systèmes ont un excès de charge positive, ce qui survient lorsque le poly (chlorure de diallyldiméthylammonium) …  Lire la suite

The results exhibited in this thesis are related to Schrodinger operators in three dimensions and are subdivided in two parts based on two published papers, [15] and [14]. A variant of Turbiner's conjecture is proved in the first paper while a partial classification of quasi-exactly solvable Lie algebras of first order differential operators in dimension three is exhibited in the second paper. This classification is then used to construct new quasi-exactly solvable Schrodinger operators in three dimensions. Turbiner's conjecture posits that, for a Lie algebraic Schrodinger operator in dimension two, the Schrodinger equation is separable if the underlying metric is …  Lire la suite

Oort gave a complete description of symplectic commutative group schemes killed by p and of rank p2g . Each such group appears as the p-torsion group scheme of some principally polarized abelian variety and this classification can be given in terms of final sequences. In this thesis, we focus on the particular situation where the abelian variety is the Jacobian of a hyperelliptic curve. We concentrate on describing the subspace of the moduli space of hyperelliptic curves, or rather the cycle, corresponding to a given final sequence. Especially, we concentrate on describing the subspace corresponding to the non-ordinary locus, which …  Lire la suite

Dufour, Carolina (Supervisor1)  Lire la suite

Using strain distribution pattern in a series of recombinant inbred strains derived from malaria susceptible A/J and resistant C57BL/6J (B6) inbred strains of mice, it was established that the genetic control of infection with Plasmodium chabaudi AS is multigenic. Quantitative trait linkage analysis in backcross and F2 crosses derived from A/J and B6 mice identified a major locus on mouse chromosome 8 (Pchr/Char2) controlling the extend of blood-stage parasite replication. The Chr.8 interval contains several candidate genes, one of them being the macrophage scavenger (Scvr) locus encoding for the scavenger receptor type A (SR-AI/AII) expressed at the surface of monocytes …  Lire la suite

Pax-3 is a transcription factors important in normal embryonic development, as highlighted by its mutation in independent alleles of the Splotch mouse mutant and human Waardenburg syndrome, both characterized by pigmentary disturbances in the heterozygous state and limb muscle defects in the homozygotes. Pax-3 contains two structurally independent DNA-binding domains, a paired domain and a homeodomain. Through the analysis of a number of naturally occurring mutations, we have shown that both DNA-binding domains are functionally interdependent, as independent mutations in either domain can affect the DNA-binding activity of the other. In support of this finding, modeling the deleterious mutations into …  Lire la suite

The purpose of this study was to determine among surgically treated non-metastatic breast cancer patients in the province of Quebec the distribution of the time between surgery and post-operative radiation therapy (RT) as well as secular trends and other factors influencing waiting time. Using administrative records, I identified between 1992 and 1998 29,105 episodes of breast cancer and 17,704 of these contained an indication of receiving RT Hierarchical linear regression models were used to identify predictors of waiting time. The number of cases of breast cancer increased by 5.5% per year while the number of those receiving RT increased by …  Lire la suite

We present new algorithms for computing local minimizers of the trust-region subproblem (TRS). This problem consists in minimizing a quadratic function subject to a ball constraint. In particular, this problem appears as a subproblem in trust-region methods for constrained and unconstrained optimization. First, by modeling the TRS with a new semidefinite program, different than the standard semidefinite relaxation, we derive an algorithm, similar in structure to the Rendl-Wolkowicz Algorithm, which implicitly solves the semidefinite program by maximizing a single variable concave function over a closed interval. Second, we extend the theory needed for this algorithm and the Rendl-Wolkowicz Algorithm to …  Lire la suite

À la pointe de la révolution numérique, la technologie 5G transforme les industries etinfrastructure et génère des avantages qui vont bien au-delà du domaine des télécommunications. Cependant, l'innovation et la commercialisation de la technologie 5G présentent des risques. Par conséquent, il est intéressant lorsque les gouvernements choisissent de soutenir l'innovation de la technologie 5G dans le secteur privé. Cet article examine pourquoi, au vu des tensions avec Huawei, le gouvernement de l’Australie a choisi d'investir dans l'innovation de la technologie 5G par l'Australian 5G Innovation Initiative. Guidé par un cadre théorique original, l'article mène une analyse thématique de la façon …  Lire la suite

We present asymptotic results for the maximum likelihood estimator of the dependence parameter arising naturally in the study of asymptotic efficiency. In particular, we demonstrate a Berry-Esseen-type estimate through a study of entropy functions. Next, we establish the large deviation principle under strict convexity assumptions and study the associated rate function. The results are shown for independent and identically distributed random variables, which we then generalize to finite state Markov chains  Lire la suite

Mu and D108 are temperate bacteriophages which can follow two possible modes of growth after infection of Escherichia coli. The bacteriophages can follow the lytic cycle, in which the bacteriophage genome is replicated and progeny phages are produced, or the lysogenic cycle, in which the bacteriophage remains dormant in the E. coli genome. In this case, the bacteriophage's DNA is replicated along with the host chromosome. Central to the lytic/lysogenic switch, is the Ner protein. Ner is a small, basic, DNA-binding protein. To better understand the mechanism by which bacteriophage D108 regulates its lytic/lysogenic switch, a plasmid containing the D108 …  Lire la suite

Quach-Thanh, Caroline (Supervisor1)  Lire la suite

Data from the Quebec swine breeding program (1980 to 2001) were used to estimate genetic parameters for longevity and to evaluate the contribution of non-genetic factors. After data verifications, there were 28,377 Yorkshire, 30,123 Landrace and 7,830 Duroc sows with records of herd life. The program 'The Survival Kit V3.12' (Ducrocq and Solkner, 2001) was used to estimate heritability separately within each breed, using a Cox proportional hazard model. The time-independent fixed effects of age at first service and of the combinations of herd with year of birth, estimated breeding value (EBV) backfat, EBV age to 100 kilograms and EBV …  Lire la suite

Sarfati, Marika (Supervisor2)  Lire la suite

Berk, Dimitri (Supervisor)  Lire la suite

Certaines observations suggèrent une influence de la vallée du Saint-Laurent sur la distribution des averses à sa surface. D'autre part, depuis quelques années, les membres du "'Stormy Weather Group" ont enregistré sur films de 35-mm les échos apparaissant sur un écran de radar doté d'un indicateur panoramique à altitude constanto (IPAC). L'utilisation de ces films permet à l'auteur d'approfondir le sujet par l'identification des premiers échos et le tracé de leur trajectoire subséquente. Des dossiers, établis pour 76 premiers échos, relient ceux-ci à la surface et au profil du terrain. [...]  Lire la suite

Part I of this thesis is mainly concerned with the determination of a necessary and sufficient condition for a compact space X to separate the Euclidean space R^(n+1). We shall find that a compact space X separates R^(n+1) if and only if there exists a non nullhomotopic mapping of X into the n-sphere S^n. We also prove in part I some of the well known theorems of topology, like “Brouwer Fixed Point Theorem” and “Brouwer Invariance of Domains Theorem”.  Lire la suite

The main object of this thesis is to solve the following problem, which was raised, a few years ago, by Fine, Gillman and Lambek. If X and Y are triangulable manifolds of dimensions m and n respectively, and if Q(X) is isomorphic to Q(Y), then m=n. (Q(X) is the maximal ring of quotients of the ring of all continuous real valued functions defined on X.) The contents of the thesis is divided into three parts. In the first, we prove some general propositions, which will be needed later. In the second part, we prove that, if X and Y are …  Lire la suite

L’infertilité est un problème clinique majeur qui affecte jusqu’à 10% des couples qui tentent de concevoir un enfant. L’infertilité peut être causée par la dysfonction de plusieurs organes qui régissent le fonctionnement du système reproductif. L’hypophyse, un petit organe situé sous le cerveau, produit et sécrète les hormones «gonadotropines» qui régulent le système reproducteur: l’hormone lutéinisante (LH) et l’hormone folliculo-stimulante (FSH). Une production anormale de LH et FSH par les cellules gonadotropes est souvent observée chez les patients infertiles. Des hormones provenant des gonades (testicules et ovaires), du cerveau et de l’hypophyse agissent sur les gonadotropes. Parmi ceux-ci, l’hormone de …  Lire la suite

À ce jour, les pays post-communistes présentent de considérables différences en termes de démocratie et de réformes économiques, ce, malgré un passé commun. En fait, seulement quelques pays d'Europe Centrale et de l'Est ainsi que les républiques Baltes, ont acquis le statut de démocraties. Pour les autres anciennes républiques Soviétiques, la norme est toute autre. La plupart d'entre elles affichent des régimes soit semi-démocratiques, ou tout simplement autoritaires. Dans le but d'expliquer cette différence, je fais appel au concept de capacité étatique, qui réfère à l'infrastructure de l'appareil d'état. À l'aide d'analyses quantitatives ainsi que qualitatives menées dans 21 pays …  Lire la suite

Background. There are two specific scales designed to assess neck pain. They have weaknesses and limited assessment. A Functional Cervical Scale (FCS) based on neck disorders disability was developed after literature review and consultation with patients and medical specialists. Thirty-two items were tested. Study design. Two hundred and ten patients with neck pain answered the FCS and other questionnaires on work, medication intake and quality of life. Another copy of the FCS was mailed to the subjects who had to return it in a pre-stamped envelope. Methods. Item selection analyses were done. Test-retest and internal consistency were calculated to assess …  Lire la suite

Symbiotic interaction of Rhizobium with roots of legume plants leads to the formation of root nodules that are capable of reducing atmospheric nitrogen. In nodule cells, bacteria are always enclosed inside the peribacteroid membrane (pbm) which is derived from the plant cell plasma membrane. The pbm mediates all the molecular exchanges between the host plant and bacteria. The pbm of soybean (Glycine max) nodules induced by Bradyrhizobium japonicum was characterized for the presence of nodule-specific proteins (nodulins), which may be involved in some of the nodule-specific roles the pbm plays. The pbm was found to contain a number of nodulins, …  Lire la suite

Knowing the oxygen level inside cancer tumors before radiotherapy can significantly affect the choice of treatment Currently, measuring oxygen levels in vivo before radiotherapy is not performed due to the lack of a simple and validated method that could be easily incorporated clinically. Recent work in Magnetic Resonance Imaging (MRI) reported that variations in fat T1 values could be used as an indirect and non-invasive method to measure tissue oxygenation. For this purpose, the Magnetization Prepared Two Rapid Acquisition of Gradient Echoes (MP2RAGE) sequence designed for brain T1 mapping and 3-point Dixon to perform fat-water separation were adapted and combined …  Lire la suite

We experimentally investigated the effect of water on the sulphur concentration at sulphide saturation (SCSS) in basaltic, andesitic, and rhyolitic melt compositions at 1250 ºC, 1 GPa, and oxygen fugacities buffered at or near the graphite-carbon dioxide (CCO) buffer in a piston-cylinder apparatus. We directly measured water concentrations in our sulphide saturated melts using Raman spectroscopy. Our experiments varied from anhydrous conditions up to 7.3 wt.% total dissolved water. Our results show an increase in the SCSS of about 100 ppm per wt.% added water in all melt compositions. We used data from our study and previous studies to create …  Lire la suite

Between 1933 and 1963, many Quebec critics followed with interest--some sporadically, others regularly--the works and career of Alain Grandbois (1900-1975). This thesis analyzes in systematic fashion the content and the evolution of their discourse. In addition to engaging in "dialogue" (via their reviews) with certain publishers, the critics reflected upon the problem of regionalism and universalism in Grandbois' "clear and simple" prose works, although in quite different ways with each new book. The collections of poems, on the other hand, because of their "hermetism", induced commentators to study the question of the intelligible and the unintelligible in poetry, a question …  Lire la suite

Anne Hebert, qui, dans "le Torrent", dépeint des fermiers, n’a jamais fait de concession à l'école du terroir. Elle n’a pas non plus conféré de fonction éthique a son écriture qui conteste (toujours davantage) les valeurs religieuses -- entreprises amorcée dès 1942 dans Les Songes en équilibre. L'indépendance de l'écrivaine par rapport aux instances moralo-nationalistes qui prétendaient régir les arts, s'accompagne d'une sacralisation de la littérature. La vie dans la famille de Maurice Hebert, les connaissances inculquées dans les nombreux établissements d’enseignement religieux qu’elle a fréquentés, les influences littéraires avouées et même l'expérience professionnelle acquise à l'ONF permettent de reconstituer …  Lire la suite

The CD45 protein tyrosine phosphatase (PTP) is a large transmembrane glycoprotein abundantly expressed on all nucleated cells of the hematopoietic system. CD45 plays an essential role in signal transduction through the antigen receptor in T and B lymphocytes, mainly through the regulation of Src-family tyrosine kinase activity. Previous work has shown that cross-linking CD45 with monoclonal antibodies can induce caspase-independent apoptosis in murine immature T cells. The exact mechanism whereby CD45 cross-linking can lead to cell death, and whether the PTP activity of CD45 is involved in this process have not been determined. In this study, a CD45-deficient T-cell line …  Lire la suite

Many low molecular weight chlorinated organic compounds produced by the pulp and paper industry during kraft bleaching of the wood pulp are toxic. Mass balance studies suggest that mineralization of chlorinated organics is occurring in pulp and paper mill wastewater treatment systems. To understand the nature of dechlorination activity, molecular tools such as oligonucleotide primers and corresponding DNA probes were developed to monitor the presence of microorganisms possessing key genes (dehalogenases) responsible for the degradation of chloroaliphatic organics in kraft pulp mill effluent treatment systems. Oligonucleotide primers designed from the coding sequence of known dehalogenases and a methane monooxygenase gene, …  Lire la suite

This thesis describes a new instrument used to study the response of the STACEE camera to different lighting conditions. It explains how the camera functions, and presents the results of different tests performed on the camera.  Lire la suite

The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is an atmospheric Cherenkov telescope that detects cosmic gamma-rays using the wavefront-sampling technique. STACEE uses the large mirror area of the National Solar Thermal Test Facility (NSTTF) to achieve an energy threshold below 200 GeV. This telescope was used to search for high-energy gamma-ray emission from the Crab Nebula and pulsar. A statistical excess of 4.07sigma in the number of on-source events compared to off-source events was detected in 15 hours of on-source observing time, corresponding to an integral flux above the energy threshold (Ethr = 185 +/- 35 GeV) of I(E …  Lire la suite

Les progrès récents en technologies mobiles, portables et de télécommunication ont favorisé la croissance de nos désirs d'interconnections sociales. En effet, l'omniprésence des appareils électroniques dans nos vies est telle que nous comptons sur eux pour répondre à nos besoins sociaux, mais aussi, parfois, pour satisfaire ces besoins par des interactions avec des agents virtuels. Qu'il s'agisse d'un appel téléphonique important, d'un rappel qu'une rencontre aura lieu ou d'une nouvelle mention ``j'aime'', nos appareils se battent constamment pour capter notre attention, causant souvent des perturbations importantes dans les contextes professionnels et sociaux, et ayant ultimement un impact négatif sur notre …  Lire la suite

In just three decades of human exploration and utilization of outer space, an unwanted legacy of thousands of artificial space debris has been left behind. The purpose of this thesis is to analyse the appropriate technical aspects of the artificial space debris issue and to explore the legal ramifications of the question. The first chapter is devoted to the technical aspects and covers topics such as the origins and location of artificial space debris, the hazards they constitute, the anticipated damage that might be caused by such debris and the likelihood of its occurrence. In the second chapter, the legal …  Lire la suite

Pourquoi les mouvements fascistes ont-ils triomphé dans certains pays tout en échouant dans d’autres ? Plus précisément, comment expliquer la victoire du fascisme en Allemagne et en Italie, alors qu’il ne parvient pas à s’implanter durablement en France, malgré des crises socio-politiques et une mobilisation de masse comparables ? La littérature propose diverses réponses, de la cohésion organisationnelle des mouvements fascistes à la stabilité des régimes, mais chacune révèle ses limites dans une comparaison systématique. Cette étude affine la thèse de la « menace rouge », selon laquelle la progression fasciste serait née de la peur d’une insurrection communiste. Elle …  Lire la suite

In this thesis the Mach reflection of cellular detonation was studied. The detonations were propagating in mixtures of C2H2 + 2.5O2, C2H2 + 2.5O2 + 70% Ar and C3H8 + 5O2at initial pressures of 3 kPa < Po < 20 kPa. Wedge angles of 10°, 20°, 30°, 35° and 40° were used. The Mach reflection was observed by schlieren photography and smoked foils. From the results it is seen that for small wedge angles (e.g. θw = 10°), the Mach stem is curved and blends smoothly with the incident detonation front with no discernible triple point. For larger wedge angles …  Lire la suite

Freshwater systems across the globe are experiencing declines in fish species richness and diversity, reflecting ongoing anthropogenic threats such as climate change, land conversion, and overharvesting. As ectotherms, fishes may be very sensitive to climate warming as their body temperature and metabolic rate increase with temperature. Warming waters are likely to interact with other stressors that affect fish aerobic metabolism, making it critical that we understand not only the independent effects of climate change on fishes, but also interactive effects driven by co-occurring stressors. Therefore, this thesis explores the potential interactions between water temperature and both turbidity and hypoxia, using …  Lire la suite

Les enzymes de synthèse de peptides non ribosomiques (NRPSs) sont des mégaenzymes élégants responsable pour la production des métabolites secondaires bioactives utiles comme agents agricoles et produits thérapeutiques. Ils sont modulaires et composés de domaines protéiques. Un module de NRPS minimal contient trois domaines centraux pour permettre l'élongation des chaînes peptidiques, incluant: le domaine d’adénylation(A), le domaine de condensation (C), et le domaine porteur de peptide (PCP). Le domaine d’adénylation sélectionne et active le substrat acyle avant de le transférer comme un thioester au domaine PCP. Ce monomère lié de façon covalente est ensuite acheminé au domaine de condensation où …  Lire la suite

The purpose of this study is to examine the issues relating to transboundary hazardous waste movements and the most recent efforts to address them at the international, regional and national levels. The transfer of hazardous wastes from the country of origin to other nations raises a number of environmental, ethical and economic concerns, particularly when developing nations are targeted as waste recipients. This work argues that the only appropriate response is the adoption of an ethical and preventive approach to the transboundary movement and management of hazardous waste. At the national level, prevention in the form of waste minimization and …  Lire la suite

This thesis focuses on the modelling and optimal control of a load-controlled fatigue structural testing rig. The modelling phase involves first attempting to analytically model the test system and the test controller, then using these models to estimate test cycle times. Afterwards, a system identification approach is taken to generate a more reliable numerical model using data. Open-loop and closed-loop methods are discussed, although only closed-loop experiments can be performed on fatigue testing rigs to prevent unnecessary damage to the valuable test article. The direct, indirect, and dual-Youla closed-loop system identification methods are applied to measurement data from a fatigue …  Lire la suite

The more detailed study of the epilepsies carried out by Dr. Penfield and his co-workers has demonstrated that luany forms of epilepsy are of focal origin (Penfield and Erickson, 1941). Very often these foci are found in the cerebral cortex. The symptoms before, during and following the seizures point to definite localizations. However, certain forms of epilepsy have defied attempts at localization. Seizures consisting of generalized convulsions, without detectable aura, involving large portions of the central nervous system, are as yet difficult to understand as the outflow of a localized source or focus within the brain.[...]  Lire la suite

Le trait de la myxospermie peut être observé à travers une large gamme de contextes environnementaux dans lesquels les cellules épidermales de l'écorce graineuse se différencient pour devenir des cellules de mucilage sécrétoires (CMS). Ces cellules produisent énormément de mucilage, qui consistant en majorité de polysaccarides qui gonflent et qui font éventuellement éclater les cellules en contacte avec l'eau. La théorie courante indique que cette gélule qui encapsule la graine confère plusieurs adaptations évolutionnaires telles que la promotion ou la prévention de la dispersion ainsi que la promotion de la germination sous conditions favorables. La composition du mucilage varie considérablement …  Lire la suite

It is indeed strange that the Assembly of the International Civil Aviation Organization (ICAO), composed of all the present 183 member States, should have no powers in connection with the principal functions of the Organization (that is, the formulation of Standards and Recommended Practices); nor any over the appointment and creation of the Organization's principal officers and sub-organs. Stranger still is the fact that even the little and insignificant powers that this Assembly might possess can be easily and constitutionally/conventionally "usurped", or interfered with, by the limited 33-member Council of the Organization. Much more puzzling is the fact that this …  Lire la suite

Despite judicial recognition of the prior sovereignty of Indigenous peoples, the aboriginal right to self-government has not yet been recognized by the Supreme Court of Canada. This paper asks: what is the scope of this right? The author uses a common law constitutionalist approach to argue that the right to self-governance includes matters not incompatible with the Crown’s assertion of sovereignty or those matters surrendered voluntarily via the treaty process. The scope of Indigenous common law jurisdiction is established by tracing the principle of continuity via the English imperial constitutional law regarding territorial acquisition in Canada. From this general relationship, …  Lire la suite

Thrombosis initiated by intravascular prosthetic devices remains a major complication of cardiovascular surgery. Blood coagulation mechanisms are reviewed with respect particularly to initiation and propagation of thrombus formation on prosthetic surfaces. The platelet' s role in thrombogenesis is emphasized. Standardization of in vivo thrombogenic models must be achieved before testing new local methods of thrombus inhibition. In this project a polished quarts ring implanted in the mongrel dog’s interior vena cava or abdominal aorta served as a thrombogenic model. Evaluation of the dog's thrombosis response to this intravascular ring revealed a highly variable response.  Lire la suite

This research is concerned with a Markov-model-based solution to the problem of lexical disambiguation in natural language. We investigate three ways of improving current statistical solutions to this problem. First, three techniques for reducing or eliminating the necessity for a manually tagged training corpus are described. Two completely automatic methods are shown to be inadequate, but a semi-automatic method is found to be effective in reducing the number of tokens which must be manually analyzed. Second, various methods of improving the tagging performance of an automatic disambiguator are described. Good-Turing and combined-order estimation techniques are shown to yield small gains. …  Lire la suite