McGill University Thèses et mémoires publiés en 2007

Self-esteem involves a variety of cognitive processes that help people perceive, interpret, and process social information. A central component of people's self-esteem is their sense of belonging and feelings of acceptance. It follows that people react strongly to social rejection and that being attuned to signs of real or potential social rejection can serve a self-protection function. However, being overly attuned and sensitive to social rejection can have a paradoxical effect, whereby aberrant attentional processes can contribute to the perpetuation of the vicious cycle of low self-esteem. The goal of the research presented in this dissertation was twofold: to investigate …  Lire la suite

The information processing theory of problem solving has emphasized search and heuristics and comparatively neglected learning, a situation that this thesis addresses. Participants learn to solve problems using environmental feedback, verbal instructions, or demonstrations performed by experts. Empirical and simulation work confirms that demonstrations and instructions are more effective for learning than binary feedback (answer correct or not). Results also show that humans successfully generalize what they learn by observation to more complex tasks, suggesting understanding rather than rote memorizing of the solutions observed. Four computational models of complex problem solving are presented. First, a reinforcement learning model is trained …  Lire la suite

In causal reasoning the presence of a strong predictor of an outcome interferes with causal judgments of a moderate co-occurring predictor. Causal competition effects have generally been demonstrated with a strong competing predictor that is followed by an outcome with a higher probability than a moderate target predictor, and that also signals as many or more of the total outcome occurrences than the moderate target predictor. Confounding these two distinct aspects of predictiveness has constrained the ability to examine their respective importance for the relative validity of predictors in causal competition. By examining the effects of one and two strong …  Lire la suite

Na+/H+ exchangers (NHE) are integral membrane proteins that catalyze the electroneutral exchange of Na+ (or K+) for H+. The nine human isoforms identified to date share the same topology of twelve membrane-spanning domains and a cytoplasmic regulatory tail, and diverge in their tissue expressions and subcellular localizations. This thesis focused on the identification and characterization of proteins interacting with the ubiquitous NHE6 isoform, which resides predominantly in recycling endosomes. Recent yeast two-hybrid (Y2H) screening of a human brain cDNA library using the regulatory tail of NHE6 as a probe resulted in the tentative identification of about 250 partial or full-length …  Lire la suite

The purpose of this qualitative research is to provide an in-depth exploration of the impact that a diagnosis of a terminal illness has on family functioning. The goal is to gain insight into adult children's personal experience when a parent is diagnosed with a terminal form of cancer. This study explores how families respond, adapt and cope when this specific family member is diagnosed with a terminal illness. It also explores any significant changes in relationships within the family and any shifts in the roles of the members and how they adjusted to such shifts. The study is informed by …  Lire la suite

The United States Supreme Court placed the major Hollywood studios in violation of antitrust laws in 1948, leading to the end of the classical Hollywood studio system of the 1930s and 1940s. Subsequent changes in the corporate organization and mode of production of the major studios signaled the end of the traditional B-movie as a product of block-booking policies. B-movies became a distinctly different entity in the 1950s, however. From the institutional effects of the antitrust ruling, to changing audience demographics, the emergent patterns in production, distribution and exhibition had a profound effect on the evolution of the B-movie from …  Lire la suite

Because children are bombarded by an abundance of information from the environment, the development of the ability to filter extraneous information in order to attend to the most relevant information is crucial for optimal information processing. The ability to effectively filter affects every aspect of children's functioning, including educational activities and social interactions. In order to assess the development of filtering with ecologically relevant factors, a forced-choice filtering paradigm in which the target and distracting stimuli were presented at different times was used to measure the speed of target identification among a group of 6-year-olds (n=10), 7-year-olds (n=12), 9-year-olds (n=13) …  Lire la suite

The Ras signaling cascade is a vital component in the processes that mediate cell survival, growth, differentiation and transformation through activation of MAP kinase (mitogen-activated protein kinase). The recent discovery of a new scaffold of the Ras signaling pathway, Kinase Suppressor of Ras (KSR), is found to be a positive effector of Ras signaling which further contributes to proliferation and transformation in the ERK/MAPK pathway. This thesis describes the roles of Ras and Kinase Suppressor of Ras 1 (KSR-1) in regulating the expression of tumor promoting genes such as urokinase plasminogen activator (uPA) in the development and progression of breast …  Lire la suite

Through the use of chronic experimental animal models, the majority of in vitro investigations of temporal lobe epilepsy have demonstrated enhanced network activity within the subdivisions of the hippocampal formation. However, clinical evidence in combination with in vivo and in vitro studies indicates that structures external to the hippocampus contribute to the genesis of seizure activity. To address the effects of limbic network excitation, I have utilized combined hippocampal---entorhinal cortex brain slices from pilocarpine-treated rats that display chronic seizures. My investigations have focused upon three structures, the subiculum, entorhinal cortex and the insular cortex. The experiments in the pilocarpine-treated subiculum …  Lire la suite

This thesis uses multiscale computational modelling to find the fundamental principles that govern defects forming during the operation of new electro-optical devices and the processing of spider silk fibers. The generalized approach developed in this thesis bridges engineering devices and biological processes based on liquid crystalline materials. Three types of defects are encountered: inversion walls, lines and points. Inversion wall defects are found in the electro-optical device when a nematic thin film undergoes a temperature-induced surface anchoring transition. Point defects naturally occur in the tubular extrusion duct of spiders, while line defects present close topological connections with point defects and …  Lire la suite

Aviation is at a turning point. Considerable improvements in aircraft emissions efficiencies are expected through technological improvements, air traffic management, and managerial strategies. But global demand for air travel is increasing at an even faster rate. Mostly for political reasons, aviation has been left behind in international efforts to tackle climate change. However, increasing pressure is on the industry for immediate action, thus making further delays impossible. This thesis is an attempt to determine the best possible course of action for the industry. To this end, it begins by assessing contemporary understanding of aviation's impact on the environment, and provides …  Lire la suite

Introduction. Injection drug users (IDUs) are at high risk for infection with HIV, hepatitis C virus (HCV), and other bloodborne viruses through the sharing of drug injection equipment. It is becoming widely recognized that the transmission of infection in this population occurs as a result of individual risk behaviours within the context of social networks. Objectives. The goal of this thesis was to identify salient features of social and drug injecting networks of IDUs that potentially facilitate infection transmission. The main objectives were: (1) to examine whether risk factors for infection depend on the characteristics of the drug network to …  Lire la suite

Inattention is often associated with early reading difficulties and to non-responsiveness to reading interventions. The aim of the present study was to explore the relationships between attention skills and literacy skills over the course of the computer-based literacy intervention, ABRACADABRA. The design included a contrast of two interventions, Synthetic Phonics and Rime, against a classroom control, enabling a comparison of different types of literacy contexts for grade one students with varying attention skills. Attention skills, as measured by both parent ratings and a sustained attention task, were found to predict reading-related skills and students' improvement over the course of the …  Lire la suite

The purpose of this qualitative study is to understand how children within a Canadian Czech diasporic context, create and discover their Czech heritage language and culture through meaningful active participation in areas provided within the constructs of a non traditional setting such as a summer camp. Five contextual areas of the camp were identified and studied. The areas are: activities, food, camp counselors, staff dynamics and location. Braziel and Mannur (2003) and Rampton's (1990) aspects of "language inheritance" and "language affiliation" inform the analysis.  Lire la suite

Through the lenses of critical pedagogy, cognitive psychology, marketing, curriculum development, traditional and informal education, and Black education, how one centre constructed and implemented critical edutainment is reviewed and scrutinized. The ethnographic study took place in a hyperreal (Baudrillard) setting using a bricolage of research methods: Seidman's 3-part interview protocol with workers and administrators; McMillan's focus group interview process with 9-12 year olds; participant-observation; field and reflective notes; and artefacts from external sources such as television broadcasts, newspapers, and official documents to gather and analyse data. In spite of its noble intentions, Gramsci's hegemony was witnessed and maintained through the …  Lire la suite

The following thesis focuses on the Italian director, Luchino Visconti and his first feature film, Ossessione. It evaluates his film in relation not only to the director's biography but also to its historical and cinematic context. It deals with the manner in which Ossessione was adapted from an American roman noir, refashioning it in its own distinctive way. In addition, it analyses the film's relation to generic modes of representation, specifically realism and melodrama, and concludes by situating the work as a precursor of the Neorealist movement of the mid-20th century.  Lire la suite

Helper-dependent adenovirus vector-mediated full-length dystrophin expression in muscle leads to significant mitigation of the dystrophic phenotype of the mdx mouse. However, dystrophin, as a neoantigen, elicits antibody formation. As an alternative approach, we evaluated gene transfer of full-length murine utrophin, a functional homologue of dystrophin that is normally present only at the neuromuscular junction. A single injection into the mdx mouse tibialis anterior muscle with a helper-dependent adenovirus vector encoding utrophin provided very good transduction, with 58% of fibers demonstrating sarcolemmal utrophin expression in the neonatally injected mice while 35% utrophin positive fibers were found in mice injected in adult …  Lire la suite

Extensive evidence supports a dimensional approach to the derivation of personality and other behavioral traits in human and animal studies, and suggests that personality traits are hierarchically organized with more specific lower-order traits combining to form higher order-traits. We used this approach in an exploration of the structure of normal behavior in juvenile and adolescent vervet monkeys in a prospective longitudinal study. The goals of this thesis were to determine whether we could successfully identify behavioral traits in >200 African green (or vervet) monkeys (Chlorocebus aethiops) based on standard well documented primatological behavioral measures in (1) social groups and (2) …  Lire la suite

The nature and effect of two approaches to instruction in mathematics were studied from a situated cognition perspective, which emphasizes the pivotal role of discourse in knowledge comprehension. Typically, students must construct conceptual knowledge representations that integrate different types of information from diverse resources. Currently, little is known about how students' cognitive processes are influenced by distinct instructional approaches. The study focused on two problem-based methods: conceptually-focused instruction (CFI) and procedurally-focused instruction (PR). Both methods implemented common principles based on cognitive theories. Moreover, different characteristics were identified in the cognitive theories having different research traditions as their source. These differences …  Lire la suite

It is widely accepted that the initial event that significantly influences biocompatibility is the nearly instantaneous adsorption of proteins from biological fluids onto the biomaterial surface. For blood-contacting devices, the complex layer of adsorbed plasma proteins is generally unfavourable and leads to major complications, including thrombus formation, inflammatory tissue responses, and microbial infections. Furthermore, protein interaction with passive films on metallic biomaterial surfaces may contribute to enhanced in vivo corrosion. To gain a better understanding of this phenomenon, the present thesis investigated the fundamental aspects of the interaction of the serum protein fibrinogen with a medical-grade stainless steel 316LVM surface …  Lire la suite

The primary objective of this thesis is to develop a framework to compare the performance of fixed-wing aircraft, airships, and the rotary-wing aircraft in the Martian environment and through that framework, determine which of these platforms is best suited to conduct a series of scientific investigations on Mars. Three Mars mission scenarios provide the context within which the performance of the platforms is evaluated. The mission scenarios are used to derive the performance requirements including the range and flight path to be covered, the altitude at which the platforms fly, and the scientific investigations to be performed along with the …  Lire la suite

Uveal Melanoma is the most common primary intraocular tumor in adults. Despite the advances in numerous ophthalmic techniques leading to the increased accuracy of diagnosing this malignancy, the ten-year mortality rate for patients has remained unchanged at approximately fifty percent. Knowing this, further understanding of the specific steps that occur within the metastatic cascade of uveal melanoma is required. Our laboratory utilizes five human uveal melanoma cell lines (92.1, SP6.5, MKT-BR, OCM-1, UW-1) of known proliferative, invasive, and metastatic potential. We used four methods to characterize the presence and roles of the chemotactic factors CXCL12, CXCL8, CXCL1 and HGF in …  Lire la suite

Although the native conformation of a protein is thermodynamically its most stable form, this stability is only marginal. As a consequence, globular proteins have a certain amount of flexibility in their backbones which allows for conformational changes in the course of their biological function. In the course of this thesis, we study protein models at the edge of stability in different contexts: (1) First, we use molecular dynamics to determine the force needed to rupture a chain molecule (an unfolded protein) being stretched at constant loading rate and temperature. When all energy bonds of the molecule are identical, we find …  Lire la suite

This essay examines varying theories on the nature and essences of classical texts from the Western literary canon. These ideas range from the notion that the classic is a single work, to viewing these great works as accommodating multiple meanings over time, to the belief that their distinguishing feature is their ability to relate identifiable and universal themes that transcend readers' particular circumstances. In exploring these three perspectives, it becomes clear that The Bible fulfills the requirements for classical designation and should therefore be regarded as a seminal part of the West's literary heritage. Finally, this paper discusses the educational …  Lire la suite

HIV infection causes the progressive decline in total CD4 T cells, leading to immunodeficiency, failure of the immune system to control pathogens and ultimately death. This loss has been attributed to a number of factors such as direct viral CD4 T cell cytopathogenicity, increased immune activation resulting in T cell exhaustion, as well as a possibly impaired function of the thymus which would halt the input of new diverse T cells. This last element has, however, been disputed as the existing methods to measure thymic function have important technical and interpretational limitations. In order to circumvent these caveats, we have …  Lire la suite

The opening sections of some exegetical Midrashim deal with the issues of authorship and inspiration, time of composition, historical setting, genre, methods of interpretation, themes, and literary forms and unity of their biblical book. This is the same type of material that is found in the introductions to medieval rabbinic Bible commentaries (written in Hebrew). In the Midrashim, this phenomenon occurs within the midrashic comments on 1:1, as opposed to outside the scriptural verse order in a separate introduction like the commentaries. Therefore, I have designated it by the phrase "Inner-Midrashic Introduction." Goldberg's form analysis of rabbinic literature is applied …  Lire la suite

Mechanical stresses and flow dynamics alteration in a stented artery region are known to stimulate intimal thickening and increase the risk of restenosis, the closure of a revascularized artery. Particle imaging velocimetry (PIV) is an optical flow visualization technique that can be used to characterize the local flow dynamics around different stent structures. However, the usual cylindrical stent geometries present visualization difficulties when using an optical measurement technique such as the PIV technique. Using a flat configuration of a stent model presents advantages over the usual cylindrical model. A planar stent model makes data acquisition easier in planes cutting through …  Lire la suite

We present an O(vopt)-approximation algorithm for the maximum leaf spanning arborescence problem, where opt is the number of leaves in an optimal spanning arborescence. The result is based upon an O(1)-approximation algorithm for a special class of directed graphs called willows. Incorporating the method for willow graphs as a subroutine in a local improvement algorithm gives the bound for general directed graphs.  Lire la suite

The objective of this study was to understand the pattern of variation in group structure and feeding behaviour of wintering Common Goldeneyes ( Bucephala clangula) on the Saint-Lawrence River, by comparing two major habitats for this species in the province of Quebec, one in freshwater and one in saltwater. Groups of goldeneyes were smaller in Montreal than in the estuary and consisted of twice as many males. Individuals spent a greater proportion of time feeding in Montreal than in the estuary. At Montreal, goldeneyes spent more time feeding under water. Temporal variables had a major influence on group structure and …  Lire la suite

Saccharomyces cerevisiae has developed mechanisms in order to survive harsh environmental conditions. This species responds to stresses such as ethanol, heat, and weak acid exposure via two well-characterized stress response pathways. These typically involve either the Hsf1p or the Msn2/4p transcriptional regulators. Recently, our lab has begun to characterize a member of the zinc cluster protein family: Asg1p (Activator of Stress Genes, systematic name: YIL130W), which is presumed to stimulate stress response genes independently of the Hsflp and Msn2/4p pathways. Previous work has revealed five target genes of Asg1p (HSP30, STP4, YER130C, TPO2, YRO2) thought to be involved in this …  Lire la suite

Optimized Schwarz methods are iterative domain decomposition procedures with greatly improved convergence properties, for solving second order elliptic boundary value problems. The enhanced convergence is obtained by replacing the Dirichlet transmission conditions in the classical Schwarz iteration with more general conditions that are optimized for performance. The convergence is optimized through the solution of a min-max problem. The theoretical study of the min-max problems gives explicit formulas or characterizations for the optimized transmission conditions for practical use, and it permits the analysis of the asymptotic behavior of the convergence. In the first part of this work, we continue the study …  Lire la suite

In this thesis, I argue that the First Nations Governance Act (FNGA) shares the colonial aspirations of other pieces of historical legislation in the Canadian context. The FNGA attempted to have First Nations' local governing structures mirror those of the Canadian state. As a result, this piece of legislation fails to recognize and respect the jurisdictional authority of First Nations over their own internal socio-political structures and systems. The FNGA is therefore a colonial assault on First Nations' jurisdiction in the realm of governance undermining the right to self-government and self-determination of First Nations. I demonstrate this by examining three …  Lire la suite

Satellites provide uniform data coverage globally. Thus, their data have the potential to reduce analysis errors in data sparse areas significantly, thereby improving numerical weather prediction (NWP) model forecasts. We describe a previously-used methodology to generate NWP model initial conditions (ICs) from satellite total column ozone data based on three principal steps: (1) convert a chemical total column ozone field to a dynamical mean potential vorticity (MPV) field via linear regression, (2) convert the 2D MPV field to a 3D potential vorticity (PV) field via vertical mapping onto average PV profiles, (3) invert the 3D PV field to obtain model-initializing …  Lire la suite

The Cbl family of E3 ubiquitin ligases are important negative regulators of multiple receptor and cytoplasmic tyrosine kinases, and participate in a wide variety of cellular processes. Uncoupling of Cbl-mediated negative regulation allows activated receptor tyrosine kinases such as the Met receptor to escape degradation, enhancing their oncogenic potential in vitro and in vivo. Despite the consequences of loss of Cbl-mediated negative regulation for human disease, little is known about the mechanisms regulating Cbl protein levels themselves. In this thesis work, I demonstrate a differential regulation of c-Cbl and Cbl-b downstream of the Met receptor tyrosine kinase. Cbl-b protein levels …  Lire la suite

Considerable data indicate that multiple sclerosis (MS) is an autoimmune-mediated inflammatory disease of the CNS. Naive CD4 T cells play a central role in this autoimmune response and occupy a niche that is homeostatically regulated. Homeostatic influences include thymic output, naive CD4 T cell proliferation and receipt of death and survival signals. Altered naive CD4 T cell homeostasis could account for increased autoreactivity of these T cells in MS. We hypothesize that RRMS patients have perturbed naive CD4 T cell homeostasis. Signal joint T cell receptor excision circles (sjTRECs) and betaTRECS are generated as byproducts of T cell receptor (TCR) …  Lire la suite

In order to analyze the relationship of punk to anarchy, this thesis will investigate the discursive function of "anarchy" both in contemporaneous accounts of punk and in subsequent histories. Beginning with the genesis of British punk and the first references to anarchy in different media during the late 1970s, subsequent chapters focus on the seminally influential anarcho-punk band Crass in order to discern their impact on the evolution of the anarcho-punk genre and its relationship to anarchism up through the mid-1980s. Several other anarcho-punk bands will also be considered for their contributions to this genre. In addition to providing an …  Lire la suite

Les filaments de vortex sont des tubes de vorticité isolés, et il est important de comprendre leur comportement pour caractériser les fluides dans lesquels ils apparaissent. La reconnection de vortex, i.e. le changement de topologie qui survient lorsque des filaments entrent en collision, est un phénomène particulier qui ne peut être modelisé par la méthode traditionnelle des vortex, ce qui mène (Ghuneim, 2002, Ghuneim et al., 2002) à l'intégrer avec la méthode des ensembles de niveau. Cependant, la complexité de l'implémentation traditionnelle de la méthode des ensembles de niveau limite grandement le type de simulations qui sont possibles. Motivés par …  Lire la suite

The synthesis and chemistry of some new cyclic diesters were investigated. The first part of the thesis is concerned with the study of new cyclic diesters derived from thiosulfurous acid, namely cyclic dialkoxy disulfides and their structural thionosulfite isomers. The second part focuses on the development of a new methodology for the synthesis of cyclic carbonates (carbonic acid diesters). The synthesis of new cyclic dialkoxy-disulfides is described in Chapter 3. Five new molecules have been synthesized and fully characterized. An X-ray structure was obtained for the 2,3-furandimethylene dialkoxy disulfide. The substrates were prepared in an attempt to rationalize some of …  Lire la suite

Constraint satisfaction problems (CSPs) provide a unified framework for studying a wide variety of computational problems naturally arising in combinatorics, artificial intelligence and database theory. To any finite domain D and any constraint language Γ (a finite set of relations over D), we associate the constraint satisfaction problem CSP(Γ): an instance of CSP(Γ) consists of a list of variables x1, x2,..., x n and a list of constraints of the form "(x 7, x2,..., x5) ∈ R" for some relation R in Γ. The goal is to determine whether the variables can be assigned values in D such that all …  Lire la suite

In this thesis, we present a strongly coupled data fusion architecture within a Bayesian framework for modeling the bi-directional influences between the scene and object classification mechanisms. A number of psychophysical studies provide experimental evidence that the object and the scene perception mechanisms are not functionally separate in the human visual system. Object recognition facilitates the recognition of the scene background and also knowledge of the scene context facilitates the recognition of the individual objects in the scene. The evidence indicating a bi-directional exchange between the two processes has motivated us to build a computational model where object and scene …  Lire la suite

Tremblay, Johanne (Supervisor1)  Lire la suite

The study objectives were to: (1) assess fetal exposure to oxidative stress by measuring amniotic fluid concentrations of nitric oxide (NO), thiobarbituric acid--reactive substances (TBARS), and ferric reducing antioxidant power (FRAP) and (2) establish whether these concentrations were associated with infant birth weight, gestational age, or oxidative stress-related conditions arising during pregnancy. Frozen amniotic fluid samples were obtained from 654 mothers undergoing amniocentesis for genetic testing during second trimester in Montreal, QC, Canada. Maternal and neonatal characteristics were collected from medical charts and questionnaires and exclusion criteria were applied. ANOVAs and multivariate regression analyses showed that NO, which differed among …  Lire la suite

The stretch reflex response helps control upright stance by countering the effects of gravity. It has been suggested that sway in the sagittal or anterior-posterior (AP) plane contributes to the modulation of the reflex response; this thesis sought to examine if a similar relationship could be discerned between sway in the frontal or medial-lateral (ML) plane and the reflex. The sway in the ML plane was characterized by changes in the center of pressure (COP) and in the vertical forces between the feet. Two experiments were carried out. The results of the first experiment, which observed the COP and the …  Lire la suite

The involvement of corticotropin-releasing hormone (CRH) and neuropeptide Y (NPY) in the pathophysiology of anxiety and anxiety-related disorders is well established. The objective of this study is to explore the genetic variations in the CRH and NPY genes in a well-documented behavioral animal model, the vervet monkey (Chlorocebus aethiops sabaeus), in order to uncover a possible association between these polymorphisms and behavioral traits quantitatively extracted following analysis of social behavior and responses to novelty challenges. The vervet CRH and NPY genes were amplified and sequenced; the priority was given to the regions expanding from -1kb upstream of the transcription initiation …  Lire la suite

Cytoplasmic male sterility (CMS) is a maternally inherited trait of higher plants that can be suppressed by nuclear restorers of fertility ( Rf) genes that normally down-regulate the expression of a CMS-associated mitochondrial gene. In Brassica napus, nap CMS is associated with the expression of the orf222/nad5c/orf2101 mitochondrial gene region and is suppressed by the restorer gene Rfn. I present here an extensive analysis of the expression of the orf222/nad5c/orf2101 region in nap CMS and fertility-restored plants. Using RT-PCR methodology, I mapped transcript initiation sites, processing sites, and 3' termini. I identified two processing events, one within and one immediately …  Lire la suite

The processing of sensory signals is an important, yet complex task in which a system must extract behaviorally relevant stimulus patterns from a vast array of sensory cues. When a neuron within a major sensory area is presented with a stimulus, one of the important characteristics used to distinguish between types of input is frequency. Often sensory neurons are tuned to narrow stimulus frequency ranges and are thus charged with the processing of subtypes of sensory signals. The weakly electric fish Apteronotus lepthorhynchus senses it's environment through modulations of a self-generated electric field. Two main types of sensory signals can …  Lire la suite

Earthworms have an important role in the decomposition of organic matter, mineralization of nutrients and physical mixing of soils. Despite a large number of laboratory and greenhouse-level studies investigating how earthworms modify soil properties and promote soil fertility, we lack reliable methods to scale-up and quantify earthworm contributions to nutrient cycling at the agroecosystem level. The objective of this thesis is to determine the influence of earthworm communities on nitrogen (N) transformations in soils and to quantify their contribution to nitrogen flux through soils for soybean and maize cropping systems of Quebec. Laboratory growth rates were used to predict how …  Lire la suite

The high performance of bone implants depends on the positive response of osteoblasts to the surface of the materials manufactured for the implant. Cell response in turn strongly depends on the nature of the initial interaction of macromolecules involved in cell adhesion and proliferation with the atomic structure of the surface of the material used for the implant. The initial interaction between bone specific extracellular matrix proteins and the solid substrate influences cell response at the cell-implant interface. This interaction is crucial for implant stability, long-term durability, and osseointegration. Despite extensive research undertaken to develop high-quality material for implants in …  Lire la suite

In vertebrates, PBX and MEIS/PREP are normally localized to the cytoplasm and are mutually dependant on one another for their translocation to the nucleus. Recently, phosphorylation and cytoskeleton anchoring to myosin heavy chain II B were proposed as regulatory factors for PBX subcellular localization. Moreover, MEIS-independent regulation of PBX1 subcellular localization has also been reported. In this study, we investigated the role of actin and myosin in the control of PBX1 subcellular localization and the PBX1-independent regulation of MEIS1 subcellular localization. Our data suggest that PBX1 interacts with actin via myosin, and the interaction interface was mapped to the PBC-B …  Lire la suite

The goals of this study were to determine the proportion of children that were identified in the 2005 & 2006 at one youth protection agency as victims of sexual abuse or as at risk of becoming victims; to describe the family members and offenders and to determine what decisions concerning treatment and restrictions of contact were consistent with a model of best practice. Information on 18 variables was collected and grouped into child, abuse, offender, and agency response categories. In total, 70 children or about 3% of investigated cases involved either victims or children at risk of sexual abuse. Best …  Lire la suite