McGill University Thèses et mémoires publiés en 2008

Angiopoietin-1 (Ang-1), the main ligand for the endothelial cell (EC)-selective Tie-2 receptors, promotes survival, proliferation, migration and differentiation of these cells. Despite its importance in various aspects of vascular biology, the mechanisms of action of the Ang-1/Tie-2 receptor pathway have not been fully explored. To identify the downstream modulators of Ang-1, we evaluated changes in the transcriptome of human umbilical vein endothelial cells (HUVECs) treated with Ang-1 protein for four hours by employing the oligonucleotide rnicroarray technology. Eighty-six genes were significantly upregulated by this treatment and forty-nine genes were significantly downregulated. These genes are involved in the regulation of cell …  Read more

Résumé Les Images des Femmes du Tiers Monde: Différence et Rupture dans les Représentations du Développement Cette thèse analyse l'usage des images des femmes du Tiers Monde par l'Agence Canadienne de Développement International (ACDI) durant la période 'Les Femmes dans le Développement' (FED). Cette analyse interprétative critique examine comment ces images, - en tant que textes institutionnels -, fonctionnent pour reproduire les notions de différence à propos des femmes et du Tiers Monde. Cette étude se penche sur la rupture entre le langage et les images du développement et analyse la manière dont les messages médiatiques véhiculent les discours relativement …  Read more

The socio-economic and political changes effected in Kerala by the British and colonial discourse at the beginning of the twentieth century challenged traditional structures of power. This eventually resulted in social mobility within various communities which, as a result, embraced modernity and began to pursue modern education. However, Mappila Muslims' long-standing tradition of struggle against colonial powers and their hatred of British rule had led them to resist the modernization process and consequently become more socially and educationally backward than other communities in Kerala. It was in this context that Vakkom Muhammad Abdul Khadir Moulavi (1873-1932), who is acknowledged as …  Read more

A Lagrangian dynamic and thermodynamic iceberg drift model was developed, coded and validated against observations. First, the model was used to create a climatology (1979-2000) of iceberg drift in the Southern Ocean. The simulation reproduced the main patterns of motion and the northernmost extent of Antarctic icebergs as inferred from satellite and ship observations. The model was then used to hindcast 29 giant iceberg drift tracks in what was the first study of an iceberg model ability to reproduce the motion of individual icebergs around the Antarctic continent on timescales of years. The shape and timing of twelve of the …  Read more

Rates of depression have been observed to increase markedly during adolescence. In addition, depression rates for adolescent girls have been reported to be up to twice those of boys. A wide variety of factors have been proposed to account for these changes, including psychological factors derived from cognitive theories of depression. Such theories have often awarded an important contributory role to a negative self-concept. In the meantime, research in child and adolescent development has revealed that the self-concept undergoes profound changes during adolescence, and that these changes affect boys and girls differently. Thus the significant sex difference in rates of …  Read more

La lumière et le bruit dans l’unité néonatale peuvent être particulièrement stressants pour les prématurés. Les buts de cette étude étaient d’évaluer chez des prématurés de 28 à 32 semaines d’âge gestationnel: a) leur stabilité physiologique (rythme cardiaque, variabilité du rythme cardiaque et saturation d’oxygène) lorsqu’ils portent des lunettes et des couvre-oreilles pendant une période de 4 heures, et b) leur réponse à la douleur lors d’une prise de sang au talon (rythme cardiaque et variabilité du rythme cardiaque) après la période de 4 heures où ils ont porté les lunettes et les couvre-oreilles. Les prématurés ont été recrutés dans …  Read more

The increase in ASMC mass is a major structural change described in airway remodeling in asthma. This increase has been attributed to ASMC hyperplasia and hypertrophy. The distance between ASMC and the epithelium is reduced suggesting expansion of the muscle bundle towards the epithelium. Recent studies have suggested a role of epithelial derived chemokines in ASMC migration toward the epithelium. We hypothesized that chemokines (Eotaxin, RANTES, MIP-1alpha and IL-8) can directly influence ASMC mass by increasing the rate of proliferation or enhancing survival. ASMCs were exposed to different concentrations of eotaxin, RANTES, IL-8 or MIP-1alpha. To test for proliferation, stimulated …  Read more

Septic shock is a leading cause of death in intensive care units. As part of the septic process, the endothelium becomes activated and propagates the septic condition. It has become evident that reactive oxygen species (ROS) are involved in the signaling of mediators of sepsis, such as tumor necrosis factor-alpha (TNF-alpha) and the lipopolysaccharide coating of gram-negative bacteria (LPS). An important source of these ROS is NADPH oxidase, which is a ubiquitously expressed enzyme complex that also exists in endothelial cells (EC). We showed that O2- from NADPH oxidase was important for LPS, as well as TNF-alpha, induction of two …  Read more

Cellular Cardiomyoplasty (cell therapy for myocardial regeneration) targets the basic pathophysiology of heart failure and represents a novel technique for augmenting the function of the failing heart. Previous studies have demonstrated massive mechanical losses in the first few minutes. Thus, efforts to reduce mechanical losses may prove more beneficial than those directed against biological losses alone. We believe that "Wash-out" into the disrupted blood vessels is responsible for these early losses. In the first part of this study we hypothesized that by increasing the size of the injectate, the amount of immediate losses can be reduced achieving better retention. Using …  Read more

Extensive emphasis on selection for milk yield with minimal attention to the animals' functional performance has increased the yield of North American dairy cattle. The high intensity of selection for production traits such as milk yield, protein yield and fat yield has also brought about a rapid increase in genetic relationships among animals. In dairy cattle, correlated response to selection for milk yield includes fertility and susceptibility to diseases. Although the high producing cows have greater net profit, they also have higher mammary and discarded milk costs associated with high production. Long-term genetic selection against clinically diagnosed diseases might be …  Read more

Blockade of the renin-angiotensin system lowers the rate of cardiovascular events in patients at risk for vascular disease and also improves endothelial function but the mechanism remains unclear. HUVECs were stimulated with Ang II (100 nM). Ang II produced a 2-fold increase in O2- production, which was measured by lucigenin-enhanced chemiluminescence. This increase was blocked by NAD(P)H oxidase inhibitor DPI, but not by eNOS inhibitor L-NAME. Ang II increased monocyte adhesion to ECs by 4.5-fold, and this increase was blocked by candesartan (AT1 receptor antagonist), DPI, L-NAME, wortmannin (PI3K inhibitor), dominant negative-AKT, and p22phox siRNA. Dominant active-AKT increased adhesion by …  Read more

The present study was carried out to evaluate the osteoconductive nature of Bio-OssRTM (natural deproteinized bone mineral) when used as an onlay bone substitute in a Guided Bone Regeneration model. The lateral surface of the mandible was exposed bilaterally, in 8 rabbits. On one side of the mandible, two titanium chambers were filled with Bio-OssRTM material and the chambers were then firmly secured to the mandible using screws. The pores in the titanium chambers were covered with a layer of Bio-GideRTM material. On the opposite side of the mandible, chambers without Bio-OssRTM were placed on the lateral side of the …  Read more

Electrical parameter profiles of human breast images can be used to simulate and analyze the anticipated effects on tissue from its interaction with electromagnetic fields involved in the cancer treatment exposure. In part, the success of this approach depends on the accuracy and precision in identifying the different tissue types. In this work, we propose two methods of segmenting human breast images with malignant tumors. The first method of algorithmic partitioning of the image involves manual color-edge contouring of the tissues using a cursor and subsequent identification of the tissue types. For the second method, MRI T1 values and thresholds …  Read more

Overexpression of the epidermal growth factor receptor (EGFR), a member of the ErbB family, and its closest homologue HER2, have been associated with aggressive tumour progression and reduced sensitivity to DNA-damaging agents. In order to block the proliferation of refractory tumors overexpressing EGFR, a novel strategy has been developed that sought to design molecules capable of not only blocking EGFR-TK, but also damaging DNA. These molecules, termed combi-molecules (CMs), have been shown to degrade under physical conditions to release another inhibitor of EGFR, and to be potent against tumor cells of various origins including breast, prostate and carcinoma of the …  Read more

Radiobiological irradiation can be performed using appropriately collimated sealed source radioisotope machines such as Co-60 units, as well with X-ray tubes and linear accelerators. The increasing research interest in delivering organ-specific or whole body animal external irradiation has led to the introduction of dedicated X-ray units for research purposes. In this work, the proprieties of a kilovoltage X-ray biological irradiator, the Faxitron cabinet X-ray system model CP160, are investigated and dosimetrically characterized. Calculation formalisms for everyday use of the radiobiological irradiator in laboratory conditions, specifically for cell cultures and small animals total body irradiation, were developed following the AAPM TG-61 …  Read more

The field of structural DNA nanotechnology utilizes DNA's powerful base-pairing molecular recognition criteria to help solve real challenges facing researchers in material science and nanotechnology, some of which include synthesis, sensing, catalysis, delivery, storage, optics, electronics, and scaffolding. In it, DNA is stripped away from any of its preconceived biological roles, and is treated as a powerful synthetic polymer. A subarea of research that our group has recently termed supramolecular DNA nanotechnology is emerging, and is proving to be a powerful complement to some of the already established rules of structural DNA nanotechnology. The work within this thesis falls under …  Read more

The primary objective of this thesis was to investigate body image at both the behavioural and neural levels. We describe three studies aimed at: (1) developing a novel digital methodology with which to assess perceptual aspects of body image during adolescence; (2) investigating perceptual accuracy and sensitivity to changes in the size/shape of body images among healthy adolescents; and (3) identifying the neural mechanisms of body perception using functional magnetic resonance imaging (fMRI). A novel library of digital images of adolescent bodies was created and used to characterize natural covariations in body size and shape using principal components analysis. Identified …  Read more

Design methodologies have evolved over the years, especially due to shrinking transistors in CMOS technology. This has encouraged the use of behavioural modelling in Matlab and Simulink over other less accurate or time consuming options for design and simulation, hence the development of TCSIM (Top-down Circuit Simulation In Matlab). The following components are modelled for this initial prototype: the output voltage limitation of operational amplifiers (opamps), the current limitation and parasitic capacitances of operational transconductance amplifiers (OTAs), the finite and nonlinear variation of on resistance in switches, and the nonideal behaviour of switched capacitor (SC) integrators. This is complemented by …  Read more

Ice accretion is a purely unsteady phenomenon that is presently approximated by most icing codes using quasi-steady modeling. The accuracy of ice prediction is thus directly related to the arbitrarily prescribed time span during which the impact of ice growth on both flow and droplets is neglected. The objective of this work is to remove this limitation by implementing a cost-effective unsteady approach. This is done by fully coupling, in time, a diphasic flow (interacting air and droplet particles) with the ice accretion model. The two-phase flow is solved using the Navier-Stokes and Eulerian droplet equations with dual-time stepping in …  Read more

An Obscure Man by Marguerite Yourcenar is the novelist's heritage to posterity. By Yourcenar's own admission, it constitutes her spiritual and literary testament. In this novel, her poetics of self-effacement reaches its culminating point, where Nathanael is portrayed as a protagonist free of any constraints because he exhibits no desire or ambition. The author paints a character who incarnates a constant passive state. But by doing so, one could argue that it is the work of fiction itself that is put into question, as Nathanael's triviality and insignificance --- hence his exemplary conduct --- represents a great threat to the …  Read more

Psychiatric advance directives (PADs) are legal documents allowing competent individuals to declare their treatment preferences in advance of a mental health crisis. The objective of this thesis is to examine psychosocial perceptions of legal and mental health professionals in Ontario and Quebec regarding their knowledge and willingness to implement PADs. Two hundred professionals---psychiatrists, psychologists, lawyers and administrative tribunal members---participated in an Web-survey measuring psychosocial perceptions of clinical, ethical, legal and implementation factors of PADs. Results indicate Quebec professionals are more willing to begin using PADs than Ontario professionals. Mental health professionals reported more concern than legal professionals for medical malpractice …  Read more

The Tumour-Node-Metastasis (TNM) classification system of tumour stage does not always reflect the actual tumour mass present at diagnosis. Recent reports propose that volumetric analysis may allow improved stratification of disease recurrence and survival in head and neck squamous cell cancer (SCC). This study aims to assess the prognostic value of tumour volume on the outcome of patients with oral cavity and oropharyngeal SCC. A retrospective review of 73 patients was completed. Tumours were outlined semi-automatically in digitized computed tomography scans, and volumes computed based on surface triangulations of three-dimensional reconstructions with novel software developed at McGill. Results illustrate significant …  Read more

Juvenile hemochromatosis (JH), anemia of chronic disease (ACD) and various inflammatory conditions such as Hepatitis C and alcoholic steatohepatitis exhibit improper handling of systemic iron. Patients with JH have mutations in either the hemojuvelin (Hjv) or hepcidin genes. Hjv appears to control the levels of hepatic hepcidin, the master hormonal regulator of iron stores. Interestingly, Hjv exists in both a cellular and soluble form that is expressed primarily in the muscle and to a lesser extent in the liver. Cellular Hjv (cHjv), localized in the liver, is a GPI-anchored protein that enhances bone morphogenic protein (BMP) mediated induction of hepcidin. …  Read more

The Simple View of Reading (SVR; Gough & Tunmer, 1986) provides a conceptual framework for describing the processes involved when readers comprehend text and strong evidence for the SVR comes from factor analytic studies showing dissociation between decoding and comprehension skills. The aim of the present study was to investigate if pre-decoding and comprehension components exist in Canadian English-speaking pre-readers (n = 36) with the use of Principal Components Analysis and to create a parent literacy questionnaire that contains parent literacy practices that may predict children's pre-decoding and comprehension skills. All children were administered a battery of pre-reading measures and …  Read more

Une série d'essais a été réalisée sur des poteaux de taille réelle soumis à des charges axiales. Les échantillons, qui avaient des quantités variables d'armature transversale, ont été construits en utilisant un béton auto-plaçant qui contenait une quantité variable de fibres métalliques. Les résultants de cette étude expérimentale démontrent que la présence des fibres influence positivement la capacité portante des poteaux. De plus, les résultats montrent que l'utilisation d'un béton renforcé de fibres métalliques (BFM) peut s'avérer une solution appropriée pour assurer une ductilité adéquate aux poteaux. L'auteur propose des modèles analytiques pour prédire le comportement de poteaux chargés uniaxialement. …  Read more

The purpose was to examine the ball catching strategies of 15 children with developmental coordination disorder (DCD) compared to 15 of their peers without DCD, and 15 younger children matched on ball skills. A ball catching activity (catching 10 consecutive balls in five different positions) and the developmental sequences proposed by Haywood and Getchell (2005) were used to evaluate movement patterns. Children with DCD caught significantly fewer balls than their peers at the chest and above the head. Children with DCD demonstrated delayed arm action catching on the right and delayed body actions when balls were projected away from body …  Read more

This work presents mathematical properties of the RSA cryptosystem. The topics of backdoors and padding algorithm are developped. For padding schemes, we give a practical instantiation with a security reduction. It is based on the compression function of SHA-1 without any chaining function. Our solution has the advantage over the previous one of removing the relation of the output length of the compression function to the length of the RSA modulus. For backdoors, improvements on definitions, existing algorithms as well as extensions of existing theorems are shown. The definitions pertaining to backdoored key generators are improved as to make their …  Read more

Bone homeostasis results from the delicate balance between bone formation, by osteoblasts, and bone resorption, by osteoclasts in a process termed remodeling which occurs throughout adult life. The tumor suppressor PTEN, which antagonizes the activity of PI3Kinase by dephosphorylating the D3 position of phosphatidyl inositol (3,4,5)P3, has been shown to be implicated in many of the same signaling pathways that are important in the differentiation and activation of both osteoclasts and osteoblasts. Very few studies have attempted to elucidate the role that PTEN may play in bone biology. Here we use a murine conditional knockout approach to specifically target PTEN …  Read more

Le gain de popularité de l'informatique orienté service fait des plateformes hôtes pour ces services un élément essentiel de l'Internet. Un exemple de plateforme est le centre de traitement de l'information qui se fie à des réserves de serveur-ressource statiques. Le contrôle direct des ressources permis par ce genre de système est un avantage, mais ces systèmes peuvent difficilement gérer des charges variables. Les systèmes ”peer-to-peer” permettent de redistribuer les ressources libres parmi les ordinateurs du réseau de façon opportuniste. Ce genre de système a le potentiel de créer une plateforme extensible, facile à déployer, et abordable. Par contre, la …  Read more

Plusieurs mouvements islamistes armes ont donne les signes d'importants changements sur le plan du comportement et de l'ideologie en faveur de la nonviolence. Les processus de de-radicalisation de ces mouvements ont conduit au retrait de dizaines de milliers d'anciens militants des rangs des supporteurs d' Al Qaida et ont eu un effet dissuasif sur ceux qui songeaient a se joindre a eux. Ces processus ont eu lieu a grande echelle en Egypte et en Algerie et a plus petite echelle en Libye, en Arabie Saoudite, au Yemen, en Jordanie, au Tadjikistan, en Malaisie et en Indonesie. Cette these porte sur …  Read more

Vengallatore, Srikar (Supervisor2)  Read more

L'hypertension et les médicaments antihypertenseurs ont été reliés au risque de cancer depuis plus de 3 décennies. Dans cette thèse, nous abordons certaines des faiblesses des études menées jusqu'ici en réalisant une étude de population observationnelle à l'aide la base de données de santé de Saskatchewan. Nous avons suivi 77887 sujets dont le traitement antihypertenseurs avait été initié entre 1980 et 1987 jusqu'à fin 2004. Une analyse cas-témoin nichée dans cette cohorte a indiqué une petite diminution du risque de cancer (toutes causes confondues) chez les utilisateurs de bétabloquants comparativement aux utilisateurs de diurétiques thiazidiques (OR incident 0.9; IC 95% …  Read more

The role of podocytes in glomerular permselectivity is tightly associated with their intricate morphology, featuring interdigitating foot processes from adjacent cells. The actin cytoskeleton is an integral component of podocyte foot processes and is regulated by a number of proteins expressed in podocytes. Rho-family of small GTPases are known key regulators of the actin cytoskeleton. This study, investigated the role of Rac1 in podocytes, using conditionally immortalized mouse podocytes (MPs). We studied Rho-GTPase activities and morphology/cytoskeleton of differentiating mouse podocytes stably expressing nephrin. We also studied the impact of transfection of various Rho-GTPase mutants and IQGAP1 mutants. We demonstrated that …  Read more

Les techniques traditionnelles utilisées en biochimie, en histologie ainsi qu'en microscopie permettent la détermination d'un maximum de trois protéines à la fois dans l'étude d'une organelle. La mise en œuvre de la spectrométrie de masse en protéomique a complètement changé le panorama d'investigation des organelles. Pour la première fois, il est possible d'étudier le panel entier de protéines présent dans un compartiment sub-cellulaire. Dans cette étude, je démontre dans un premier temps que l'utilisation du dénombrement de peptides redondants permet la quantification des protéines et donc la capacité de comparer l'abondance relative de différentes protéines dans un échantillon complexe tel …  Read more

While most people with schizophrenia face the functional consequences of a lifelong disorder, very few studies have investigated the specific domain of daily living activities performance. The purpose of this thesis was to examine the relationships between daily activity performance, cognitive deficits, and community functioning in people with schizophrenia. More specifically, the objectives were: 1) to describe functional limitations during daily task performance, 2) to explore the existence of subgroups of participants with similar functional limitations profiles, 3) to explore the relationships between daily task performance and cognitive functions as well as 4) with community functioning. This thesis tested the …  Read more

Lorsqu'une personne se tient entre un projecteur et une surface d'affichage une ombre apparaît. Nous démontrons une méthode pour éliminer les ombres en utilisant la poursuite d'objets par caméras et un modèle tridimensionnel d'une pièce, qui inclut les caméras, les projecteurs et les surfaces plates. Pour la poursuite de personnes, quoique nous utilisons des caméras, d'autres méthodes fonctionneraient. Pour obtenir le modèle, nous avons adapté et utilisons des méthodes de calibration géométrique existantes. Avec l'information sur la poursuite et le modèle, notre algorithme trouve dans l'image d'un projecteur la région qui est occluse par une personne. Un autre projecteur peut …  Read more

La dépression peut se manifester à tout moment au cours de la vie d'un individu. Toutefois, l'adolescence est une période où le risque d'un épisode initial est plus élevé. Puisque la dépression chez l'adolescent est un prédicteur important de la récurrence chez l'adulte, des études examinant différents modèles étiologiques de la dépression durant l'adolescence ont émergé afin de (a) comprendre le développement initial de la dépression et (b) réduire les taux de récurrence durant la période adulte. Jusqu'à présent, les études portant sur la dépression chez les adolescents ont généralement utilisé un devis transversal ou à deux temps de mesure. …  Read more

Previous studies show that recovering alcoholics exhibit deficits in perceiving facial affect. The present study investigates whether these deficits are present prior to the onset of alcoholism. Participants with a family history of alcoholism (FHP) and participants without such a family history (FHN) selected the emotion label they felt most closely corresponded with stimuli viewed on a computer screen. Zuckerman's Sensation Seeking Survey was also completed. The data revealed a relationship between family history of alcoholism and the perception of facial expressions. Additionally, FHP participants were higher in sensation seeking compared to FHN participants and high sensation seekers were less …  Read more

In this work, we study the effects of disorder on quantum Hall systems. We introduce controlled disorder by developing several ion implantation techniques in the context of two-dimensional electron systems. While the transport lifetime depends linearly on the implantation density, the quantum lifetime remains unchanged until the disorder produced by the implantation exceeds a certain critical dose. We fully characterise the defects (size and shape) created by the implantation, by essentially using the two-dimensional electron gas as an in-situ detector. We subsequently study the effect of disorder on various properties of quantum Hall systems, particularly in relation with the interplay …  Read more

A recombinant aminopeptidase (pepN) of Lactobacillus rhamnosus S93 was encapsulated in chitosan-coated alginate beads using an extrusion method. The effects of alginate, CaCl2, chitosan concentrations, hardening time, pH, and alginate/enzyme ratios on the encapsulation efficiency (EE) and the enzyme release (ER) were then investigated. Chitosan in the gelling solution significantly increased the encapsulation efficiency (EE) and also retarded the enzyme release (ER) from the beads. The greatest EE was observed in a pH 5.4 solution (chitosan-CaCl2) during bead formation. Increasing the CaCl2 concentration over 0.1 M neither affected the EE nor the ER. Increasing the hardening time beyond 10 min …  Read more

The synthesis of doped diamond films for electrochemical applications has raised an interest in developing novel techniques that could permit the production of large surface electrodes. A Thermal RF-ICP torch provides accurate nitrogen incorporation into the plasma phase without the addition of undesired contaminants. The diamond film is deposited on a molybdenum substrate at higher growth rates than other plasma CVD processes (low pressure plasmas). A detailed study on bias enhanced TP-CVD of diamond identified the optimum substrate temperature (1000oC) and improvement in the deposition qualities by applying a biasing potential. A negative potential is applied for increased nucleation and …  Read more

Tribocorrosion is a term used to describe the material degradation due to the combination of electrochemical and tribological processes. Due to a synergetic effect, the material loss can be larger than the sum of the losses due to wear and corrosion acting separately. In this thesis, the synergy of wear and corrosion was investigated for different types of material, namely the Ti-6Al-4V alloy, the SS316L stainless steel coated with a thin film of Diamond Like Carbon (DLC), and the SS301 stainless steel coated with a thin film of chromium silicon nitride (CrSiN). A tribocorrosion apparatus was designed and constructed to …  Read more

Semiconductor nanoparticles, or quantum dots (QDs) are being increasingly applied as luminescent labels in optical studies for biophysical and cell biological applications due to their unique spectroscopic properties as compared to traditional organic fluorescent probes. However, the intermittency in the fluorescence emission of QDs, commonly referred to as 'blinking', is suggested to affect transport studies using fluctuation correlation techniques. The QD size has also been suggested to be sterically limiting for some studies. The focus of this thesis work is to examine the photophysical blinking properties and steric size effects of QD nanoparticles and determine how they influence biophysical measurements …  Read more

Semiconductor nanocrystals known as quantum dots (QDs) are emerging as an important new class of fluorescent probes in cell biology due to their many advantageous optical properties. Various methods have devised that allow for the selective targeting of QDs to biological cells. Conjugation of QDs to small biomolecules has proven effective, allowing for their uptake into mammalian cell lines. We explored the use of folate conjugated QDs in the selective targeting of model cell lines known to have high expression of the folate receptor (FR). Characterization of QDs and QD conjugates is examined using techniques such as spectroscopy, transmission electron …  Read more

In this thesis, a simple moving boundary technique has been suggested, implemented and verified. The technique may be considered as a generalization of the well-known "ghost" cell approach for boundary condition implementation. According to the proposed idea, the moving body does not appear on the computational grid and is allowed to move over the grid. The impermeable wall boundary condition is enforced by assigning proper gasdynamic values at the grid nodes located inside the moving body close to its boundaries (ghost nodes). The reflection principle taking into account the velocity of the boundaries assigns values at the ghost nodes. The …  Read more

Uveal Melanoma (UM) is the most common malignant intra-ocular tumor in adults. Despite the high accuracy of clinical diagnosis and advances in local treatment, more than 50% of UM patients develop metastasis within ten years of initial diagnosis. NM23 is a human metastasis suppressor gene. Reduced Nm23-H1 expression is correlated with high metastatic potential in a variety of different cancers including melanoma. C-Met is a receptor tyrosine kinase (RTK) that has been known to stimulate the invasive growth and increase the metastatic potential of cancer cells. Expression of c-Met is correlated with high mortality rate in UM patients. Treatment with …  Read more

La progranuline est une glycoprotéine sécrétée se composant de sept répétitions et demi en tandem du motif de granuline riche en cystéine. La progranuline est capable de moduler la prolifération et la migration de cellules et est aussi impliquée dans différents mécanismes biologiques tels que l'homéostasie épithéliale, la cicatrisation, le système immunitaire ainsi que la différentiation sexuelle du cerveau et la formation de tumeurs. Récemment, des mutations du gène de la progranuline chez l'homme ont été associées à une forme de démence autosomale fronto-temporale dominante. Malgré le nombre élevé de publications rapportant l'implication de la progranuline dans de nombreux événements …  Read more

As a debate over the legitimacy of the liturgical use of images, the Byzantine Iconoclastic controversy (ca. 726-843) had important political and theological implications, which modern scholarship generally tends to treat unconnectedly. The primary object of this study is to explicate the relationship between the political and theological dimensions of the controversy and to reconstruct the debate over images in a comprehensive approach that accounts for both its political and theological dimensions. The main argument of the thesis is that the question of images was a politico-theological problem and the prospects of 'political expediency' and 'theological propriety' were correlated in …  Read more

In this research, the effects of gas composition, elapsed time of reaction and temperature on scale formation and descaling of low carbon steel were investigated and results were discussed from the viewpoint of the phase composition of the scales, oxidation rates, oxidation mechanisms, adhesion, fracture mechanics, porosity and residual scale. The phase composition and morphology of scales grown under conditions similar to those of reheating furnaces were analyzed. Low carbon steel was oxidized over the temperature range 1000-1250°C in gas mixtures of O 2-CO2-H2O-N2, O2-H 2O-N2 and O2-CO2-N2. The mole fraction of each phase, wustite (FeO), magnetite (Fe3O 4) and …  Read more

Le procédé d'injection sur renfort (RTM) est de plus en plus utilisé en industrie automobile pour produire de grands volumes de carrosseries à faible coût. Cependant, les paramètres du procédé peuvent avoir un effet négatif sur les propriétés mécaniques et le fini de surface de la pièce produite. Une résine polyester insaturé (UP) mixée à des nano-charges organiques confère de meilleurs paramètres de production, ce qui est une préoccupation majeure pour le fini de surface des pièces RTM. Les nano-charges sont des particules faites de couches de silicate traitées pour assurer leur compatibilité avec différentes résines. Plusieurs techniques pour synthétiser …  Read more