McGill University Thèses et mémoires par auteur commençant par T

Mineral fertilizer use in sub-Saharan Africa is still low compared to other regions in the world. Understanding this lack of fertilizer use has been a major task in the literature on technology adoption. In this study, I explore the long-term effects of an information and/or voucher treatment on three main outcomes: retention of information, subjective perceptions of soil fertility, and adoption of fertilizers and its impact on yields. Although randomization has been used extensively recently to disentangle the causal impact of an intervention on adoption and knowledge, most studies do not follow farmers over an extended period to establish long-term …  Read more

Introduction. Trauma triage protocols are important because they identify, at the injury scene, patients with major injuries requiring transfer to a Level I trauma center, from those with non-major injuries who could be treated at Levels II and III trauma centers. The Pre-hospital Index (PHI) is a physiological injury severity measure which may be used as a trauma triage tool. Purpose. The purpose of the present study was to: (1) prospectively evaluate the predictive ability of the PHI in identifying trauma patients with major versus non-major injuries, and (2) develop a trauma triage scale which incorporates, along with the PHI, …  Read more

Although mechanisms have not been identified, animal and epidemiological studies suggest that tricyclic antidepressants (TCAs) promote tumor growth in humans. Recently, a study in fruit flies differentiated between two types of TCAs: genotoxic ones, which were found to be carcinogenic, and non-genotoxic ones, which were not. Consistent results were found, in an epidemiologic study, in humans' breast cancer. We carried out a historical population-based case-control study to determine whether the use of TCAs increases the risk of developing any of four cancer types (breast, prostate, and ovarian cancers, and non-Hodgkin's lymphoma). The effects of the use of different classes of …  Read more

L'analyse des risques sismiques et l'évaluation de la vulnérabilité systémique donnent des informations utiles aux responsables de la Séucitré Civile pour la préparation des plans d'urgence, la mitigation des risques et le rétablissement des services à la suite d'un tremblement de terre. L'objectif de cette étude est de de développer une méthodologie pour intégrer l'analyse des risques sismiques à une modélisation de l'évacuation de la population et des services d'urgence pour mieux comprendre les éléments affectabt la vulnérabilité systémique dans une zone urbaine. Les étapes de l'étude incluent: (a) la modélisation de l'évacuation des personnes suite à un séisme dans …  Read more

Lipnowski, Michael (Supervisor1)  Read more

Rouleau, Guy (Supervisor1)  Read more

To evaluate the relationship of the natural law of the Universe and apply it to a concept of man-made or man-defined law, one must consider to some extent the over-all picture of the Universe as we know and understand it today. Primarily our main concern is the small portion of the world in which we, as individuals, reside. Occasionally we broaden our concern to our state and nation, and possibly to our world. Until recently our interest has been with our law (as each individual or sovereign nation sees it), our control, our flight in space.  Read more

Chemical reactions involve ordinarily the breaking of bonds in the reacting molecules and the formation of bonds in the products; they are usually accompanied by changes in enthalpy. Although the stability of a molecule or a radical, as expressed in terms of bond strengths, and its reactivity do not necessarily go hand in hand, a knowledge of the former is essential for the full understanding of the other factors which influence the course of a chemical process. [...]  Read more

Chemical changes involve the breaking of bonds in the reacting molecules and the formation of bonds in the products; they are usually accompanied by energy changes. Although the stability of a molecule or a radical, as expressed in terms of bond strengths, and its reactivity do not necessarily go hand in hand, a knowledge of the former is essential for the full understanding of the other factors which influence the source of chemical processes. In consequence, it is evident that the magnitudes of bond dissociation energies are of fundamental importance for both chemical kinetics and chemical equilibria.  Read more

Rea, John (Supervisor1)  Read more

...then time killed the wind... is an original musical composition scored for percussion quartet and electronics with a duration of fourteen minutes. This work explores metaphorical relationships between biological processes and musical processes. The primary constructive element in the work is a rhythmic language based upon the assignment of rhythmic cells to genetic sequences. Furthermore, biological models such as inverted repeats, zeitgeber, 2-D representations of DNA and cross-breeding were applied to musical parameters such as form, pitch, harmony and live electronics.  Read more

A general method of transforming aldehydes via $ alpha$,$ beta$-unsaturated esters to the 3-substituted glutarimide ring was developed and was applied to the construction of ring A of $(-)$-sesbanimide A (1) and the AB ring moiety of (+)-sesbanimide A (2). The phase-transfer-catalyzed methylenation reaction of dihydroxy dithioacetal 46 brought about a 1,4-migration of the t -butyldiphenylsilyl group to provide 1,3-dioxolane derivative 49. Model studies towards the synthesis of (+)-sesbanimide (2) and C-15 desmethyl sesbanimide 93 were carried out using allylsilanes 74, 79 and 94, with aldehydes 56a and 85. The synthesis of 8- O -benzyl-13- O-t -butyldimethylsilyl sesbanimides 88, 13-deoxychloro …  Read more

L'impacte de la migration de main d'oeuvre sur les ménages ruraux en Chine est devenu une matière d'intérêt pour les chercheurs à l'exterieur comme à l'intérieur de la Chine. Les membres de ménage qui restent dans leur village sont désigné comme 'oubliés'. Ce mémoire explorer les 'oubliés' du village de Gansu en Chine en se baseant sur des entrevues avec 48 ménages. L'auteur conclut que le titre d'oublié est limité étant donné que les ménages ruraux s'engagent dans des stratégies de migration liées au cycle de vie et participent dans multiples stratégies à but de générer de l'argent en combinant …  Read more

Despite its enduring popularity in performance circles, Carl Nielsen's Wind Quintet, op. 43 (1922), has received little attention from the scholarly community. This thesis provides the most comprehensive examination of the work to date and includes original analyses of each of the three movements. Moreover, it illuminates and defines stylistic trademarks that are found not only in this piece, but also within Nielsen's oeuvre more broadly. These traits include the weakening of tonal design, the liberal use of chromatic harmonies, contrapuntal writing, and the allusion to and distortion of traditional forms. This thesis highlights Nielsen's synthesis of traditional and idiosyncratic …  Read more

Solid-state reactions are vast and have great importance in synthetic chemistry. In particular, solid-solid reactions using mechanical force i.e. mechanochemical reactions, are advantageous as they are normally conducted at ambient temperature and pressure, do not require bulk solvents, which are often hazardous, and can rapidly transform inexpensive and readily accessible starting materials into products of high value. Whilst mechanochemistry has been widely used for the synthesis and investigation of new forms of pharmaceutical solids, such as salts, solvates, polymorphs and cocrystals, its use for the synthesis of molecules of actual active pharmaceutical ingredients (APIs) via covalent bond formation has not …  Read more

Les abondantes protéines de la famille p24 sont conservées dans l’évolution et circulent dans la voie sécrétoire précoce, mais leurs fonctions cellulaires sont encore mal définies. Ils sont dispensables chez la levure, mais un knock-out de p23 est létal embryonnaire chez la souris. De plus, p23 est impliqué dans la pathogénèse de la maladie d’Alzheimer. Les protéines p24 peuvent former des hétéro-complexes. Dans cette étude, les interactions des p24s sont déterminées par double hybride. Elles sont spécifiques et se font surtout par leur domaine GOLD avec une contribution de leur séquence DOG. Les expériences de mutagénèse révèlent que deux p24s …  Read more

This dissertation examines informal learning with hip hop culture in a participatory filmmaking project with thirteen youth, two producers, and two coordinators making a documentary about the role of hip hop in the lives of young Montreal hip hop artists. This research is situated between the literature of out-of-school learning and hip hop based education and is theoretically informed by critical pedagogy and cultural studies. It explores the fluidity of hip hop identities of young adult hip hop artists. Of informal educators, it asks how youth participation and empowerment are constructed in youth media projects. My methodology is informed by …  Read more

Preparations of rabbit muscle D-ribulose-5-phosphate-3-epimerase (EC 5.1.3.1) and yeast (Candida utilis) transketolase (EC 2.2.1.1) were adapted from published procedures. The purification of D-ribulose-5- phosphate-3-epimerase produced a sample of the enzyme that was free from D-ribose-5-phosphate ketol isomerase (EC 5.3.1.6) and this was used to prepare the substrate D-xylulose-5-phosphate from D-ribulose-5-phosphate. In the purification of transketolase, the procedure was modified from nine steps to three (initial extraction, acetone fractionation, DEAE Sephadex chromatography). This yielded sufficiently pure transketolase for the "photometric” epimerase assays. Assays of the levels of D-ribose-5-phosphate ketol isomerase, D-ribulose-5-phosphate-3-epimerase, transketolase and transaldolase (EC 2.2.1.2) were made on extracts of …  Read more

The urinary excretion of total etiocholanolone and four delta5-3beta-hydroxysteroids viz, pregnenediol, 17alpha-hydroxy-pregnenolone, pregnenetriol and dehydroepiandrosterone isolated from the glucuronide and sulphate fractions by sequential hydrolysis, have been compared between normotensive controls and hypertensive subjects. Normotensive subjects excreted significantly more etiocholanolone, pregnenetriol and dehydroepiandrosterone sulphates while no difference was observed in the rest of the steroids. Upon the intravenous injection of pregnenolone-14C and pregnenolone-3H-sulphate, hypertensives excreted in their urine more l4C and less 3H radioactivity than. normotensives. The urinary production rates of pregnenolone and pregnenolone sulphate calculated from pregnenediol-14C-glucuronide and pregnenediol- 3H-sulphate respectively were both higher in hypertensives but only the …  Read more

Geologists have drawn many conclusions from qualitative and quantitative geological studies in regard to past climatic conditions on the earth. Criteria formulated to determine ancient temperatures, or "paleotemperatures", can be divided into geological, mineralogical and ecological criteria. For example, tillites and pellodites are generally considered as being geological evidence of glacial conditions. [...]  Read more

De grandes incertitudes existent quant à la charge estimée de sédiments transportés sur la surface terrestre et atteignant les océans du monde. Le manque d'informations fiables sur la quantité de sédiments dans les rivières limite notre compréhension de l'impact des sédiments sur les écosystèmes fluviaux et l'environnement en aval. Pour répondre au manque général d’observations de sédiments dans le monde, de nombreuses études ont tenté de développer des modèles d'érosion et de transport de sédiments à l’échelle mondiale dans le but d'affiner les estimations de la charge sédimentaire. Bien que des progrès considérables aient été accomplis dans la modélisation du …  Read more

La qualité du malt de l'orge est un trait complexe mais important pour les secteurs du maltage et de l'industrie brassicole. Plusieurs QTLs associés à la qualité du malt sont localisés sur le chromosome 4H de l'orge. Cependant, les gènes associés à ces QTLs sont inconnus. Par conséquent, nous avons utilisé le système de transposons Ac/Ds afin de caractériser ces QTLs. De nouvelles lignées comprenant une insertion unique de l'élément Ds (TNPs) ont donc été produites grâce à la réactivation séquentielle du transposon Ds chez des lignées reconnues comme ayant un élément Ds unique à proximité de ces QTLs. La …  Read more

An asymptotic solution is given for the integral equations governing the induced screen currents for a slit aperture in a non-planar screen formed by two inclined halfplanes. The rigorous results from this solution indicate the presence of a reflection interaction effect in the Fresnel diffraction field for certain non-planar screen geometries. [...]  Read more

This longitudinal study examines a change in the language of instruction for Mathematics and Science (M & S) subjects from Bahasa Malaysia (BM) to English in Malaysia. This policy, known by the acronym of PPSMI, has two objectives: to promote student learning of M & S, and also to increase students' proficiency in English. The Education Ministry also chose to create a washback effect by introducing a bilingual high-stakes secondary exit exam. The study uses a framework which combines the perspectives offered by literature on educational change, content-based instruction (CBI) and washback in language testing to examine PPSMI. The research …  Read more

Mammalian target of rapamycin (mTOR) est une kinase sérine/thréonine fortement conservée qui contrôle la croissance des cellules. Chez le Saccharomyces cerevisiae, en plus de son rôle comme régulateur de croissance, TOR abaisse le contenu nucléaire de facteurs de transcription spécifiques et contrôle ainsi l'expression des gènes de réponse au stress. Dans les mammifères, nous avons déjà identifié un complexe macromoléculaire contenant la protéine mTOR, son kinase PKCδ et le facteur de transcription STAT1. Notre hypothèse est que mTOR contrôle le contenu nucléaire de STAT1 par un mécanisme similaire à celui observé chez Saccharomyces. Dans l'étude courante, nous avons démontré que …  Read more

Contexte: Les macrophages sont des cellules immunitaires innées essentielles jouant un rôle clé dans l’homéostasie tissulaire, le développement, l’inflammation et la réparation. Bien que les macrophages constituent le type cellulaire inflammatoire prédominant dans la dystrophie musculaire de Duchenne (DMD), leur ontogenèse et leurs caractéristiques phénotypiques ne sont pas encore entièrement élucidées. Dans cette étude, nous avons cherché à déterminer les contributions des macrophages dérivés de progéniteurs embryonnaires par rapport aux macrophages d’origine médullaire dans le diaphragme de souris saines et dystrophiques (mdx), ainsi qu’à caractériser leurs phénotypes. Résultats: En utilisant la technologie de scRNA-seq et des modèles de souris chimériques, …  Read more

Waves in shallow water are computed by moving blocks of water in the direction of the flow by the Lagrangian method. Mass and momentum in the blocks are re-distributed onto the fixed Eulerian mesh to minimize distortion at each increment of time. This Lagrangian blocks on Eulerian mesh (LBEM) method is introduced as an alternative to the classical finite volume methods. The method is positive-depth definite and free of numerical oscillation. A large number of numerical computations are carried out to evaluate the accuracy and the computational stability of the LBEM method. The results of 6 publications in journals and …  Read more

MacKenzie, Dr. R.E.  Read more

Over the past four decades, gallium nitride (GaN) based materials have revolutionized the fields of LED lighting, power electronics, and communications. Owing to their wide bandgap, substantial electromigration rate, and high breakdown voltage, GaN-based catalysts have also achieved significant success in chemical conversions such as water-splitting, methane activation, and N2 reduction. To expand the toolbox of the GaN-based catalyst, this thesis focuses on the development GaN-based catalyst and its modification strategies for directly functionalizing readily available compounds to high value-added chemicals.In Chapter 1, the fundamentals and common performance enhancement strategies of semiconductor catalyst are introduced. The development history and properties …  Read more

This study compared the cost-effectiveness of four tuberculosis (TB) control strategies for detecting and treating latent tuberculosis infection (LTBI) among long-term travellers to countries where TB incidence is elevated. The decision analysis considered hypothetical cohorts of travellers from Canada and the United States (U.S.) to Mexico, Haiti, and the Dominican Republic. Strategy I consisted of screening for incident infection via two-step tuberculin skin testing prior to travel and skin testing upon return from abroad, followed by standard LTBI treatment with isoniazid for skin test converters. Strategy II carried the additional recommendation of isoniazid treatment for individuals who screen positive for …  Read more

Christou, Nicolas V. (Supervisor)  Read more

Naphthyridine, as defined by C.F.H. Allen, is the name commonly given to the ring system resulting from the fusion of two pyridine rings through two adjacent carbon atoms, each ring thus containing only one nitrogen atom (1). [...]  Read more

Glucosiduronates and non-glucosiduronates of various estrogens were measured in 6 different human late pregnancy urine samples. The difference between the amount of free steroid released by solvolysis alone and by the sequential use of B-glucuronidase and solvolysis was taken to represent the sulfoglucosiduronate. Estriol was shown to be present predominantly (93%) as the glucosiduronate, compared with 72% for the ring D α ketols. In the case of 16-keto-17β-estradiol, 15% was present as the sulfoglucosiduronate, and 19% as sulfate; in marked contrast, 20% of total 16α-hydroxyestrone was the sulfoglucosiduronate with only 3% as the sulfate. Urinary conjugates were also anaIyzed following …  Read more

Poser, Ernest G.  Read more

Il existe un besoin mondial d'améliorer les compétences et les capacités médicales. Une approche cruciale pour répondre à ce besoin consiste à renforcer les compétences de raisonnement clinique des étudiants en professions de santé. L'apprentissage autorégulé (SRL) et le flow sont deux concepts clés qui soutiennent l'apprentissage des étudiants, à la fois dans l'instant et sur le long terme. Bien que des liens théoriques entre ces concepts existent, peu de recherches ont exploré l’interaction entre les expériences de flow et le SRL. Cette étude vise à examiner les expériences de flow des étudiants en professions de santé (médecine, soins infirmiers, …  Read more

CBA spleen cell suspension “filtered” through cotton wool or x-irradiated did not produce plaque-forming cells (PFC) when stimulated by sheep red blood cells in vitro. Partial reconstitution of the PFC response in mixtures of the 2 preparations and a complete response in mixtures of “filtered" and suboptimal concentrations of normal CBA cells suggest the participation of 3 cell-types. CBA "filtered" cells responded also in the presence of untreated C57BL spleen cells, which alone did not respond in vitro. Using CBA "filtered" cells and C57BL normal spleen cells, derived from thymectomized, x-irradiated, and bone marrow protected mice; utilizing iso-antisera directed against …  Read more

Données fonctionnelles sont des mesures qui sont censées être généré à partir d'une fonction lisse sous-jacent varie sur un continuum tels que le temps ou l'espace. Modèles linéaires fonctionnels ( FLM ) et fonctionnelle prolongée analyse de redondance (FERA ) sont des méthodes d'analyse de régression qui étudient les relations entre prédicteur fonctionnelle et variables dépendantes. En réalité, les données fonctionnelles pourraient provenir de population hétérogène et en ignorant cette hétérogénéité au niveau de la grappe se traduirait par des inférences statistiques biaisées. Pour capturer l'hétérogénéité de niveau des grappes dans les données fonctionnelles, diverses approches de clustering ont été …  Read more

The Upper Devonian Leduc, Nisku and Wabamun/Stettler formations (Frasnian and Famennian) were deposited on extensive carbonate platforms, and form three unconformity bounded megasequences, characterized by stacked shallowing upward meter to tens of meter-scale paracycles. Carbonates interbedded with evaporites have been extensively dolomitized. Four types of dolomites are recognized. Microcrystalline dolomites are interpreted to be of sabkha origin, characterized by fine crystals (2--70 mum) and are in part mudcracked, brecciated and contain quartz silts. Sucrosic dolomites (20--130 mum) commonly have dusty cores with clear rims. Mosaic dolomite crystals (10--140 mum) are interlocked. Dolomite rhombs (30--70 mum) occur in partially dolomitized limestones. …  Read more

Two perceived limitations of conventional atomic spectrometry were addressed in these studies. One limitation is that the time required for sample preparation can exceed the actual analysis time by two or more orders of magnitude. High pressure homogenization in combination with high speed blending was evaluated for the preparation of slurries which could be directly analyzed by graphite furnace atomic absorption spectrometry (GF-AAS). Cadmium, copper and lead concentrations were successfully determined in certified reference materials (CRMs) of biological origin and frozen cervine liver and kidney. By capping the flat valve head of the homogenizer with a ruby disc, metal contamination …  Read more

Several methods can be used in cluster-randomized studies with binary outcome, including GLMM, GEE, and ordinary logistic regression. In this thesis, we study cluster-randomized data with large cluster sizes relative to the number of clusters (for example, the PROBIT study). We compared GLMM, GEE, and ordinary logistic regression approaches in terms of parameter interpretation, magnitude, and standard errors of model parameters. A simulation study was performed to evaluate the performance of these methods. GLMM implemented with penalized quasi-likelihood performed well. It gave the highest empirical confidence interval coverage of the true coefficients at 95% level of confidence. GEE was robust …  Read more

Palladium, being impermeable to all gases except hydrogen, has been widely studied for hydrogen extraction in recent years. The specific surface area of the membrane is an important factor affecting the hydrogen permeation rate. How to obtain a palladium membrane with a high specific surface area is a great challenge for material scientists. In this study, a novel template-assisted technique was used to prepare nano-structured palladium membranes with a greatly increased hydrogen contacting surface. First, the anodic aluminum oxide (AAO) template was fabricated by anodizing electro-deposited aluminum film and commercially available aluminum foil. The template was then filled with palladium …  Read more

Frothers are commonly used in mineral flotation processes to reduce bubble size, slow bubble rise, and stabilize froth. Frother chemistry (structure) plays an important role in determining these functions. In this thesis, over 50 surfactants (mainly from two frother families, alcohols and polyglycols) were investigated to determine the structure effect on bubble rise velocity. The structural variables were: alkyl chain length in alcohols and polyglycols, the number of propylene oxide (PO) and ethylene oxide (EO) groups in polyglycols and location of methyl branch and hydroxyl group in alcohols. The bubble rise velocity profile was determined over 350 cm in a …  Read more

Lijun Sun (Supervisor2)  Read more

“at the still point” is a composition for full orchestra that explores the concept of non-duality by reflecting in a special way the poem by T.S. Eliot, Burnt Norton, first of the Four Quartets. The dissertation comprises two volumes: the score and the analysis. In the broadest sense, the composition metaphorically re-presents the sentiments expressed in the poem through a process known as an ekphrasis. The form and structure of a section of the poem also inform certain technical aspects of my composition. More specifically, a tripartite continuum was created in “at the still point” for each of three compositional …  Read more