McGill University Thèses et mémoires publiés en 2007

In this dissertation, we explore the effect of variable evolutionary rates on phylogenetic inference. In the first half of the thesis are introduced the biological fundamentals and the statistical framework that will be used throughout the thesis. The basic concepts in phylogenetics and an overview of Bayesian inference are presented in Chapter 1. In Chapter 2, we survey the models that are already used for rate variation. We argue that the CIR process---a diffusion process widely used in finance---is the best suited for applications in phylogenetics, for both mathematical and computational reasons. Chapter 3 shows how evolutionary rate models are …  Lire la suite

This thesis proposes a general overview of the three principal critical approaches to images of female madness in the work of Andre Breton, more specifically in his narrative Nadja. Grounded, respectively, in a Freudian, a feminist and a mythocritical perspective, these approaches tend to present a negative vision of Nadja's madness. After examining the arguments made by proponents of each approach, this study seeks to lay the foundations for positive analyses which will allow for the rehabilitation of female madness and the foregrounding of the link between insanity and female identity. Breton at once desired and fostered this feminine condition, …  Lire la suite

The rat model of global anoxia at birth has been used extensively to investigate effects of perinatal hypoxia on central nervous system function. Less research has characterized behavioural phenotypes resulting from birth hypoxia. Experiment 1 examined maternal behaviour (licking/grooming, retrieval) directed toward pups born vaginally (Vag), by caesarean section (CS) or by caesarean section with anoxia (CS+anox). Similar levels of maternal care were observed across all birth groups indicating that the sequelae of birth hypoxia in the rat are not mediated by differential postnatal maternal care. Experiment 2 investigated the effects of birth hypoxia on prepulse inhibition (PPI) and latent …  Lire la suite

Pain sensitivity is typically reduced in individuals with higher blood pressure although the nature of this relationship is poorly understood. Relatedly, the ingestion of sweet tasting solutions has been shown to reduce pain, possibly by an opioid mediated mechanism. The objective of the present research was to investigate the effects of blood pressure and sweet taste on pain sensitivity in healthy adults. The first aim was to test whether blood pressure interacts with sweet taste to affect pain sensitivity. The second aim was to test whether endogenous opioids mediate the effects of sweet taste and blood pressure on pain. In …  Lire la suite

In this thesis, the optimal location for a large format, organic food retail store is determined using the Huff Model in Montreal, Canada. The Huff Model has been widely used in marketing analysis to determine the optimal location in a variety of contexts. First, the study used Statistics Canada 2001 food expenditure data for Montreal to generate a double log linear food expenditure model for Montreal consumers. Variance Inflation Factors were calculated to test if there were multicollinearity problems, and a Breusch-Pagen test was done to test for heteroskedasticity. Neither of the results showed any statistical problems. Second, AC Nielson …  Lire la suite

The continuum design sensitivity analysis (CDSA) has been applied to the magnetostatic and electrostatic force calculation. This method allows the computation of the net loading force on a body as well as the force distribution on the surface of the body. An algorithm for force calculation combined with a standard field analysis software package is presented. The efficiency and accuracy of the method is proved through the numerical implementation applied to a set of test examples. In addition, the new approach has several advantages over the traditional methods based on the Maxwell Stress Tensor, such as no air gap or …  Lire la suite

In attempting to control the power output of a wind farm, it is first necessary to smooth the power fluctuations due to wind turbulence. This is accomplished by spatial smoothing, whereby the high frequency power components of a single wind turbine generator (WTG) is reduced by a factor of N-1/2, where N is the number of WTGs in the farm. For this reason the first part of the thesis is concerned with developing a model of smoothing in a wind farm and justifying it mathematically. After spatial smoothing, the wind farm output still contains low frequency fluctuations. The second part …  Lire la suite

Cette recherche préliminaire examine les facteurs qui peuvent influencer les modèles mentaux d’un groupe spécifique d’utilisateurs d’un moteur de recherche sur le Web: Google, mesurés selon l’étendue de leur réussite.Une échelle de cette réussite en suivant un modèle mental a été constituée en adaptant les modèles présentés par Borgman, Dimitroff et Saxon, incluant la perception (1) de la nature du moteur de recherche sur le Web, (2) des caractéristiques de la recherche propres à ce moteur, (3) de l’interaction entre le chercheur et le moteur de recherche. A l’aide de cette échelle, le niveau de réussite par un sujet donné …  Lire la suite

Cyclic guanosine 3', 5'-monophosphate (cGMP) has recently emerged as an endogenous regulator for controlling or reversing cardiac hypertrophy. Increased protein accumulation is a key feature of cardiac hypertrophy; thus, our study investigates the effects of a cGMP analog on protein accumulation in primary culture of adult rat cardiomyocytes and dissects out the mechanisms involved. We confirmed that a cGMP analog, 8-bromo-cGMP, inhibits phenylephrine (PE)-increased accumulation of newly synthesized proteins in cultured adult rat ventricular cardiomyocytes. Firstly, we have obtained data showing that 8-bromo-cGMP does not inhibit phosphorylation of S6K1 by PE during short time treatment (10 min to 2 h), …  Lire la suite

The sequencing of the human genome revealed that the number of genes does not explain why humans are different from other organisms like mice and dogs. Instead, it is how genes interact with each other and the environment that separates us from other organisms. This motivates the study of genetic networks and, consequently, my research. My work delves into the roles that simple genetic networks play in a cell and explores the biotechnological aspects of how to uncover such genes and their interactions in experimental models. Cells must respond to the extracellular environment to contract, migrate, and live. Cells, however, …  Lire la suite

Regionalized trauma systems have repeatedly been shown to improve outcomes. However, until now, we did not know which elements of these systems and to what degree these elements improve outcome. Trauma systems and the components which comprise them were originally devised based on expert opinion. They have subsequently been shown to significantly improve the outcome of injured patients in many systems throughout the world over the last thirty years. Our primary objective was to bring an evidence-based approach to the creation and running of trauma systems, based on outcomes related to specific elements which make up the structure of the …  Lire la suite

Carbonation curing of concrete products has shown potentials for CO2 capture and storage with environmental, technical and economical benefits in global greenhouse gas mitigation exercise. The primary objective of this study is to investigate the effect of early age carbonation on mechanical performance and pH of concrete in an attempt to understand the process and promote large scale applications. It was found that significant early strength was developed in cement and concrete through early age carbonation curing. The early strength could be maintained and improved due to subsequent hydration. Twenty-eight-day strength of carbonated cement and concrete was comparable to that …  Lire la suite

Replicating data across different databases has the potential to provide low response times since data can be accessed locally, high scalability since load can be distributed, and fault-tolerance since the data can be accessed as long as one replica is available. A big challenge of database replication is to handle updates such that the entire replicated database appears as if there is only a single logical copy of the data. The standard correctness criterion for database replication is 1-copy-serializability (1-copy-SE) which guarantees that a replicated database behaves as a non-replicated database with serializability (SE), the highest isolation level for transaction …  Lire la suite

In this study, lipo-chitooligosaccharide (NodBj-V (C 18:1, MeFuc); LCO) 10-7M, extracted from Bradyrhizobium japonicum, was sprayed on the leaves of soybean cv. OAC Bayfield soybean and Evans x L66-2470 (carrying the rj1 mutation, and unable to nodulate). Leaf SA level and activities of the PR proteins chitinase, beta-1,3-glucanase and guaiacol peroxidase (GPOX) were quantified. Phenylalanine ammonia-lyase 1 (PAL1) and isoflavone synthase 2 (IFS2) relative gene expression levels in the sprayed leaves were quantified using quantitative real-time PCR. Messenger RNA abundance was quantified using microarrays. The treatment caused a transient increase in local salicylate levels 24 h after exposure, and a …  Lire la suite

Effets d’un traitement hormesis aux UV-C sur la qualité post-récolte des tomates Les pertes après-récolte des fruits et des légumes sont relativement élevées. Quoique que l’utilisation du froid a permis d’accroître de façon marquée la durée de conservation de plusieurs fruits et légumes, ses effets bénéfiques sont limités sur les produits sensibles au froid comme la tomate (Lycopersicon esculentum Mill.). Des essais en laboratoire ont été effectués pour évaluer les effets d’un traitement hormesis au rayonnement ultraviolet (UV-C) sur la qualité de la tomate. Ce traitement aurait pour effet de causer un stress physiologique bénéfique qui se traduirait par une …  Lire la suite

This thesis examines differences between organic and conventional farm and operators' characteristics, and identifies which characteristics explain whether a farm is organic or conventional. The data comes from the 2001 Canadian Census of Agriculture, which makes this study the first that is national in scope and includes detailed analysis of the differences between organic and conventional agriculture using a large sample size. Farms were divided into three groups: conventional, primarily organic, and mixed production (some organic production). Parametric and nonparametric tests were used to analyze farm and operator characteristics. Logistic regression was used to determine which variables explain whether a …  Lire la suite

The general problem of plastic buckling of flat metal plates is a fundamental area of investigation in mechanics not only because of its intrinsic importance in the design of engineering structures, but also because it still has not been settled in a satisfying manner. Which theory of plasticity is the correct one to predict the buckling loads in the plastic range is a long-argued problem. This thesis presents finite element analyses of plastic buckling and postbuckling behaviour of columns and plates, taking into account the presence of initial out-of-plane imperfections. The FE programs constructed by the author for this purpose …  Lire la suite

The inclusive production of the neutral strange particles, Λ, Λ and K0S , has been studied with the ZEUS detector at HERA. The measurement provides a way to understand the fragmentation process in ep collisions and to check the universality of this process. The strangeness cross sections have been measured and compared with Monte Carlo (MC) predictions. Over the kinematic regions of interest, no Λ to Λ asymmetry was observed. The relative yield of Λ and K0S was determined and the result was compared with MC calculations and results from other experiments. A good agreement was found except for the …  Lire la suite

Activity of the cystic fibrosis transmembrane conductance regulator (CFTR) is tightly regulated by cAMP-dependent phosphorylation, but the protein phosphatases (PP) that dephosphorylate and inactivate CFTR remain poorly understood. Differential regulation of single CFTR channels by protein phosphatase 2C (PP2C), protein phosphatase 2A (PP2A) and other phosphatases has been reported. The results suggest multiple protein phosphatases are required for complete CFTR deactivation, and that PP2C may be the primary phosphatase regulating CFTR in human airway and colonic epithelia, two major sites of disease. The goal of this project was to identify PP2C isoforms that regulate CFTR. Six isoforms of PP2C reported …  Lire la suite

While Quality of Life (QOL) among aging populations has been attracting more and more attention in the last few years, little QOL research has been carried out among the elderly Chinese minority. This is a cross sectional study aimed at estimating the Quality of Life (QOL) and exploring QOL indicators among the elderly Chinese people living in Montreal. Forty-one volunteer study participants, 65 years or older were recruited from 12 Chinese community centers in Montreal. Their QOL was measured by the Ferrans and Powers Quality of Life Index (1985). The study results showed that participants generally described a very high …  Lire la suite

In order to better quantify the continuous net ecosystem exchange (NEE) at the farm scale, a 24 m high transportable tower-based eddy covariance and profiling system was tested during three field campaigns during the summer and autumn of 2006. The profile measurement system, equipped with a low-cost closed-path infrared gas analyser (LI-840) was designed to measure the carbon dioxide (CO2) storage especially during weak mixing periods under stable conditions. A tethered blimp-based measurement system for the nocturnal boundary layer (NBL) budget technique was deployed on several calm nights to compare with the concentrations and fluxes determined with the profiling system. …  Lire la suite

For some Aboriginal people, healing is a relatively new word that seems to have emerged and taken on a life of its own only after the 1990 Mohawk Crisis and the ensuing Royal Commission on Aboriginal Peoples (RCAP, 1996). In spite of the massive 4000-page RCAP report, some mainstream authorities (Brasfield, 2001) still believe that the meaning of Aboriginal healing has not been fully explained. In this study, an attempt will be made to widen the meaning of Aboriginal healing by examining ancient Haudenosaunee (People of the Longhouse) philosophy, historical cultural upheaval, and narratives from First Nations survivors of Indian …  Lire la suite

Uveal melanoma is the most common primary malignant intraocular tumour in adults and despite advances in treatment of the primary tumour, the 10-year survival rate remains unchanged. The most frequent cause of death for patients of this disease is liver metastases. Removal of the primary tumour before clinical presentation of metastases, however, has no effect on patient outcome. In order to understand the interactions between single malignant cells or sub-clinical metastases and affected organs, we have successfully developed a novel animal model of uveal melanoma. We utilized the unique properties of green fluorescent protein, a skin-flap in vivo imaging technique, …  Lire la suite

Recently, new findings allow us to suggest that lifelong exposure to endogenous estrogens could be a reliable predictor of the effect of exogenous estrogens on cognition and the brain. Thus explaining why women do not arrive at menopause with an equivalent susceptibility to the effects of estrogen therapy (ET) In the current thesis, studies have been designed to investigate the effect of estrogens on the brain from a new perspective by introducing new measures. Firstly, we developed a questionnaire about indices of lifelong estrogen exposure and assessed the reliability of these self-reported indices over a four year interval. Secondly, we …  Lire la suite

Hybrid poplars are fast-growing trees, well-suited for the production of bioenergy and wood products. They are often planted on marginal agricultural lands where soil fertility is low. The application of nitrogen (N) fertilizers is expected to replenish soil N reserves and support hybrid poplar productivity throughout the short-rotation growth period. The objective of this thesis was to assess the effect of two organic N fertilizers, papermill biosolids and pig slurry, on tree growth, nutrient uptake and soil fertility in a Populus trichocarpa x Populus deltoides hybrid poplar plantation. I also evaluated how these organic amendments influenced N transformation rates and …  Lire la suite

This study examines the decision-making activities and communicative activities of two groups participating in a simulated medical emergency activity: the control group (CG) using a traditional whiteboard and the experimental group (EG) using a structured interactive whiteboard. The two groups differ in that the EG has a structured template to annotate and share their arguments with each other. Data analysis of the decision-making activities focused on planning, data collecting, managing, and interpreting patient data. Data analysis of the communicative activities focused on informative, argumentative, elicitative, responsive, and directive acts. In the early stage of decision-making the EG spent significantly more …  Lire la suite

The thesis includes two essays on asset pricing. In the first essay, "Asset Pricing in a Monetary Economy with Heterogeneous Beliefs", we shed new light on the role of monetary policy in asset pricing by focusing on the case where investors have heterogeneous expectations about future monetary policy. Under heterogeneity in beliefs, investors place bets against each other on the evolution of money supply, and as a result, the sharing of wealth in the economy evolves stochastically over time, making money non-neutral. Employing a continuous-time, general equilibrium model, we establish these fluctuations to be rich in implications, in that they …  Lire la suite

This thesis presents a Lagrangian formulation of the Euler equations for subsonic flows. A special coordinate transformation is used to define the Lagrangian coordinates, namely the stream function and the Lagrangian distance, in function of the Cartesian coordinates. This Lagrangian formulation introduces two new geometry state variables, and a Lagrangian behavior parameter defining a pseudo-Lagrangian time used during the iteration procedure to obtain the solution for subsonic flows. The eigenstructure and characteristics analysis for the new system of equations is based on a linear Jacobian matrix-mapping procedure, which starts from the well-known eigenstructure and characteristics in the Eulerian plane and …  Lire la suite

Low carbon bainitic steels microalloyed with Nb, Ti and V are widely used for the pipeline, construction and automobile industries because of their excellent combination of strength, toughness and weldability. Boron as another major alloying element has been also frequently used in this type of steels since the 1970s. The purpose of adding boron is to improve the hardenability of the steel by promoting bainite formation. It has been realized that Boron can only be effective as a strengthening element when it is prevented from forming BN and/or Fe23(C, B) 6 precipitates. Therefore, Boron is always added together with other …  Lire la suite

Gender and socioeconomic inequalities in health are ubiquitous in developed countries; however, the modifying effect of gender on the relationship between socioeconomic position (SEP) and health over time is less clear. The potentially different health effects of changes in SEP on changes in health for working-age women and men are examined over a 10-year period. Three main questions are addressed: (1) are there gender differences in health over time, (2) do changes in SEP lead to health inequalities and (3) do changes in SEP impact health differently for women and men? Generalized estimating equations (GEE) were used to analyze the …  Lire la suite

Netrins are bifunctional axon guidance cues, known to play an integral role in spinal cord development. It has previously been hypothesized that netrin-1 can regulate synaptogenesis by increasing the chances of axo-dendritic contact by causing axonal and dendritic branching and filopodial formation (N. X. Tritsh, M.Sc. thesis). The current study further investigates the role of netrin-1 at the rodent synapse. The results of this study indicate a possible role for the netrin receptor DCC and netrin-1 in spine morphology. Morphological changes were observed in dendritic spines of netrin-1 and DCC knock-out and heterozygous mice. The phenotypes observed in these mice, …  Lire la suite

This thesis traces the history of Jewish Bible interpretations of Genesis 38, a story that is significant for the history of the early Israelites and today's Jews, as it purports to describe the origins of the Davidic line. I have exposed the possible implications of this account throughout history by exploring interpretations from biblical to modern times and have attempted to define the various difficulties that are addressed. This history is presented as a dialogue and, in this way, I have explored the intricate connections between interpreters and their proposed understandings of the narrative.  Lire la suite

As operating frequency increases and device sizes shrink, the complexity of current state-of-the-art designs has increased dramatically. One of the main contributors to this complexity is high speed interconnects. At high frequencies, interconnects become dominant contributors to signal degradation, and their effects such as delays, reflections, and crosstalk must be accurately simulated. Time domain analysis of such structures is however very difficult because, at high frequencies, they must be modeled as distributed transmission lines which, after discretization, result in very large networks. In order to improve the simulation efficiency of such structures, model order reduction has been proposed in the …  Lire la suite

Photomultiplier tubes (PMTs) are used to detect light that comes from gamma-ray-initiated showers in the earth's atmosphere. The gains of the PMTs are key to determining the amount of light detected and, subsequently, the energy of the incoming gamma ray. In this thesis, a new method of measuring the gain of a PMT is proposed. It relates the PMT gain to the variance of the PMT signal divided by the average current. The new method is mathematically motivated, tested with a series of experiments, and verified using simulations. In addition, it is compared with an existing method of measuring the …  Lire la suite

Vitamin D is a precursor to a steroid hormone, 1,25 dihydroxyvitamin D (1,25(OH)2D). After its discovery and the characterization of its receptor, the vitamin D receptor (VDR), it was initially thought only to be involved in calcium homeostasis, but further research revealed an important role for vitamin D in the regulation of cell growth and differentiation of such cells as osteoblasts and bone marrow adipocytes. 1,25(OH)2D has also been shown to be a strong inhibitor and pro-differentiator of keratinocytes. The anti-proliferative and pro-differentiative properties of this hormone have led to studies where 1,25(OH)2D anticancer properties were assessed and initial findings …  Lire la suite

Linguistic dysfluencies known as mazes have been interpreted clinically as reflecting breakdown in language formulation. Nevertheless, the relatively limited available research has suggested that maze frequency increases with linguistic complexity and that mazes are produced more frequently by children with specific language impairment (SLI) than normal language (NL) peers. This study examined the hypothesis that greater maze production by children with SLI results from their processing limitations. Language samples of school-age children with SLI (n = 9) and NL (n = 11) were collected in contexts varying in task demands: conversation, narration and expository discourse. Both groups produced significantly more …  Lire la suite

This thesis is concerned with the design and implementation of radio frequency (RF) power amplifiers and micro-electromechanical systems---namely MEMS varactors. This is driven by the many wireless communication systems which are constantly moving towards increased integration, better signal quality, and longer battery life. The power amplifier consumes most of the power in a receiver/transmitter system (transceiver), and its output signal is directly transmitted by the antenna without further modification. Thus, optimizing the PA for low power consumption, increased linearity, and compact integration is highly desirable. Micro-electromechanical systems enable new levels of performance in radio-frequency integrated circuits, which are not readily …  Lire la suite

Dual-phase (DP) steels consisting of a ferrite matrix with dispersed martensite particles have attracted a significant interest due to their combination of high work hardening and ductility. A great deal of experimental work has been done to obtain a better comprehension of the relation of their mechanical behaviour to their microstructural characteristics. In the present work, a micromechanical study of ferrite-martensite DP steels is conducted. The deformation of ferrite is described by a rate-dependent crystal plasticity theory, which relates the stress-strain field equations on the grain level to the macroscopic behaviour of the material. The crystal plasticity theory assumes that …  Lire la suite

Whalen, Joann Karen (Supervisor2)  Lire la suite

Aboriginal youth well-being is an increasingly important topic. Research with mainstream populations highlights two keys to well-being, namely perceived personal control, and a clear sense of self-identity. However, despite relevance for Aboriginal groups, underappreciated to date is the potential role of perceived collective control, and clarity of collective identity, for well-being. Thus, the present program of research investigated the impact of collective control and identity on the well-being of Aboriginal youth. Residents of two Cree communities in northern Manitoba collaborated in the research. Based on community members' input on important community and youth issues, we developed two surveys on youth …  Lire la suite

In the first section of the critical part of this thesis, we study the phenomenon of simultaneous narration in first-person singular prose fiction. In the second section of the critical part, we outline the defining traits of the omniscient "I"; by proposing this figure, we fill in a gap in current narratological theory. The second part of this thesis, a short piece of prose fiction, is written in the first-person singular and uses simultaneous narration. The "I" is omniscient and occasionally exercises this power. The text begins when the heroine, Sarah, decides to tell the story of the rest of …  Lire la suite

This thesis explores the significance of digital cinematic technology within the independent film community. The main objective of this study is to demonstrate how various forms of digital technology (including cameras, non-linear editing software, and projection systems) are "democratizing" the processes of production, post-production, distribution, and theatrical exhibition.  Lire la suite

Background. An online research network was set up among 11 dentists and 2 researchers in Montreal to test the feasibility of data collection over one year. Objectives. We evaluated the pilot participants' experiences and their perspectives regarding its potential utility. Methods. One-on-one qualitative interviews with 4 researchers, 4 dentists, and 3 policy makers. Interviews were recorded on audiotape and transcribed for coding and interpretation. Results. Although feasibility of data collection was evident in the pilot results; qualitative data revealed the limitations of the pilot, the unmet expectations, and the lack of impact of research findings. In terms of potential utility; …  Lire la suite

The investigation conducted for this thesis endeavoured to determine to what extent a relationship exists between pre-service elementary school teacher enjoyment of participating in science laboratory activities in a university-level background science course and their understanding of the science involved in those activities. A student enjoyment score for two science laboratory activities was generated from survey data. A student understanding score was generated from responses to relevant questions on the final exam of the course. A step-wise logistic regression was then conducted on the student enjoyment and understanding scores. Within the scope of the investigation described in this thesis, the …  Lire la suite

The uppermost Cambrian-Lower Ordovician Kamouraska Formation in the external Humber Zone of the Quebec Appalachians consists of dominant thick massive to graded quartz arenite beds, subordinate pebble conglomerate and intercalated thin shale and siltstone beds. It was deposited by hyperconcentrated to concentrated density flows in a meandering submarine canyon on the continental slope bordering the Iapetus Ocean. Turbidity currents deposited beds with turbidite structure divisions. The sandstones consist of well sorted, well rounded quartz sand with frosted grains. Scanning electron microscopy reveals the presence of textures supporting eolian transport before redeposition in the deep sea. The Kamouraska quartz arenites are …  Lire la suite

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly worldwide. Due to the inadequacy of current pharmacotherapies, novel molecular targets must be sought as potential therapeutic candidates. Furthermore, there is a need for more efficient and cost-effective animal models of this pathology in order to accelerate in vivo investigations. Our laboratory is in possession of human choroidal neovascular membranes which we examined for expression of cyclooxygenase (COX)-2. This expression was characterized in retinal pigment epithelial, vascular endothelial, and fibroblast cells and correlated with patient age. We also looked at the feasibility of creating a rabbit laser-injury …  Lire la suite

Transforming growth factor beta (TGFbeta) and Angiotensin II (AngII) signaling occurs through two distinct receptor superfamilies, the serine/threonine kinase and G protein-coupled receptors (GPCRs). Through diametric actions, TGFbeta and AngII regulate various biological responses, including cell proliferation and migration. Previously, we identified the G protein-coupled receptor kinase 2 (GRK2), which acts through a negative feedback loop mechanism to terminate Smad signaling. To investigate the impact of TGFbeta-induced GRK2 expression on GPCR signaling, we examined its effect on AngII signaling in vascular smooth muscle cells (VSMCs). We show that activation of the TGFbeta signaling cascade results in increased GRK2 expression levels, …  Lire la suite

Islamic Law in Canada: Marriage and Divorce provides an analysis of how Canadian society and the Canadian judicial system have responded to the use of the Shari'a to resolve issues relating to Islamic marriage and divorce in Canada. This dissertation explores two instances where Canadian society has been forced to address the role of the Shari'a in Canada and its interaction with Canadian laws and values. The first involves the debate that took place in Ontario over the last decade concerning the use of Islamic arbitration in family matters. This public debate ultimately led to the rejection of faith-based arbitration …  Lire la suite

The reverse transcriptase of the Human Immunodeficiency Virus type 1 (HIV-1) is responsible for transcribing the viral single-stranded RNA genome into double-stranded DNA. Due to its vital role in the viral life cycle, it is often targeted in the treatment of HIV-1 infected patients. Inhibitors that block the reverse transcriptase enzyme were shown to interfere with nucleotide incorporation. At the end of a nucleotide incorporation cycle, the newly incorporated substrate is still located in the nucleotide binding site. In order to continue the elongation of the DNA chain, the enzyme has to move by one nucleotide relative to the nucleic …  Lire la suite

The goal of conformal radiation techniques is to improve local tumour control through dose escalation to target volumes while at the same time sparing surrounding healthy tissue. Respiratory motion is known to be the largest intra-fractional organ motion and the most significant source of uncertainty in treatment planning for chest lesions. A method to account for the effects of respiratory motion is to use four-dimensional radiotherapy. While analytical models are useful, it is essential that the motion problem in radiotherapy is addressed by both modeling as well as experimentally studies so that different obstacles can be overcome before clinical implementation …  Lire la suite