Digital Commons Network^™

The Process Of Obtaining And Retaining Employment Among The Vision-Restricted, Chelsea E. Mohler

Digitized Theses

National estimates indicate that only a small percentage of vision-restricted individuals are employed. Identified obstacles to employment include lack of access to assistive technology, inadequate transportation, and negative attitudes of potential employers. A constructivist Grounded Theory methodology was used to gain an in-depth understanding of what people with vision-restrictions, who perceived that they are successfully employed, considered to be fundamental in the search for employment. Three themes emerged from the analysis of their responses: facing and negotiating barriers, the cyclical process of seeking and keeping employment, and settling for second best. As a person with a vision-restriction, I am uniquely …

The Effect Of Socio-Economic Status As Measured By Education On Outcomes In Scleroderma (Systemic Sclerosis), Samah Mansour Assaad Mansour

Digitized Theses

The goal of this study was to assess socioeconomic status (SES) as a social determinant of outcomes in patients with systemic sclerosis (SSc). In systemic lupus erythematosus, SES has a large effect on outcomes. It is unknown what the effect of SES is on outcomes in SSc. SES is often measured by income, occupation and education. In SSc, highest education would be attained decades prior to disease onset whereas current income and occupation could be low due to SSc and thus would confound interpretation of effect of SES on SSc. Therefore, education was used as a measure of SES in …

Longitudinal Associations Between Temperament, Social Competence, And Internalizing Disorders Risk In Middle Childhood, Sarah V.M. Mackrell

Digitized Theses

While psychopathologists posit that temperament plays a critical role in internalizing disorder (i.e., depression and anxiety) risk, the mediators of this risk are poorly understood. Additionally, no previous studies have examined whether temperament traits interact to predict risk mediators. The current study examined longitudinal associations between temperament and social competence in middle childhood, a likely mediator of temperamental risk for psychopathology, using a multi-method approach. A sample of 205 7-year-old children was assessed for temperament using laboratory and parent-report measures. At age 9, these children completed a stress task that entailed social evaluation,before and after which cortisol samples were collected. …

Rac1 And Rhoa-Rock Regulation Of Osteoblast Differentiation On Rough And Smooth Titanium Surfaces, Paul David Henry Prowse

Digitized Theses

Modulation of surface topography is an effective way to control cellular response and enhance osseointegration of implants; however it is unclear how surface topography influences osteoblasts at the molecular level. One of the most frequently observed changes in cellular behaviour is the organization of the cytoskeleton and actin polymerization which is regulated by the Rho-family of GTPases. We hypothesized that these GTPases (specifically Racl and RhoA), play a role in osteoblast response to surface topography and affect differentiation and mineralization. Osteoconductive rough topographies and non- osteoconductive smooth topographies were used as models to elucidate the roles of Racl and RhoA. …

A Microfluidics Approach To Novel Polymeric Microspheres Reinforced With N-Ti02, Sepideh Rezvani

Digitized Theses

ABSTRACT

Polymethylmethacrylate (PMMA) is a brittle polymer used for both commercial dental and bone cement applications. Its poor mechanical properties leads to implant failures requiring revisions which is a tremendous current problem as we live longer and more active lives. The objective of this work was to produce microspheres of PMMA containing titanium dioxide (Ti02) nanofillers that have the potential for enhancing the mechanical properties of these cements. To make the TiC>2 nanofillers organophillic to be compatable with PMMA, a variety of bifunctional molecules were examined for coordination to the Ti02 nanospheres through a -COOH functionality. These bifunctional molecules …

Demonstration: Monstrous Operations In Sculptural Production And Display, Jason Charles Hallows

Digitized Theses

Sculpture is an equivocal medium, at once occupying the abstract space of representation and the real space of the viewer. This dual nature often produces an uncanny or monstrous experience for the viewer who feels drawn into the space of the work, and who is met by its disruptive, but evasive presence. This monstrous condition is revealed in modem and contemporary sculptural practices that have sought to complicate the dynamics of the relationship that sculpture has had with the furniture used in its production and display. Manipulations of the pedestal and the workbench, in various degrees of integration with the …

Investigating The Time Course Of Propionic Acid- Induced Cognitive Deficits Using The Morris Water Maze, Jennifer Mepham

Digitized Theses

Dietary and gastrointestinal factors may be associated with the development/worsening of autistic symptoms in a subset of patients. Propionic acid (PPA) is a metabolic byproduct of gut bacterial fermentation.

Intracerebroventricular (ICV) infusions of PPA in rodents produce transient behavioural and biochemical changes similar to those seen in autism. The permanence of the cognitive deficits associated with the PPA rodent model of autism was assessed using adult male rats in the Morris water maze (MWM).

Following an ICV regimen of PPA or vehicle (2x/day, 7 days), rats were tested in the MWM (acquisition) and then one week later for reversal. On …

Studies On Biomedical Engineering Applications Of Fine Powder Technology, Wen Shi

Digitized Theses

Powder coating is a coating process that applies the coating materials to a target substrate in dry powder form. As an alternative coating technique to liquid coating technique, powder coating has many advantages, such as environmental friendly, low cost, high efficiency in materials usage. However, problems such as unable to handle ultrafine cohesive powders limit the application of powder coating technology in industry. With a new invention that can effectively fluidize ultrafine powders by enhancing their flowability, a novel electrostatic ultrafine powder coating technique has been developed by our group. Based on this novel technique, many functionalized powder coatings have …

The Meaning Of Health And Help Seeking Behaviours Among Refugees Who Have Experienced Collective Violence In Their Countries Of Origin: A Canadian Perspective, Gracia Mabaya

Digitized Theses

This study aimed at understanding the meaning of health and the help seeking behaviours, pre and post migration, of refugees who have experienced collective violence in their countries of origin. An interpretative phenomenological approach with a purposive sample of three men and three women was used. Prior to migration, the participants’ meaning of health was deeply influenced by their experience of collective violence, which rendered their embodied experience of life as non-existent and meaningless. Access to health care was limited by the unavailability of sound medical infrastructures and lack of finances. Post migration, the perception of their health and help …

Characteristics And Function Of Connexin43 Mutants Linked To Oculodentodigital Dysplasia, Robert James Lorentz

Digitized Theses

Oculodentodigital dysplasia (ODDD) is a rare developmental disease that results from any one of over sixty known autosomal-dominant or autosomal-recessive mutations in the gene GJA1, which encodes for connexin43 (Cx43). In the current study, we assessed the characteristic of six Cx43 mutants, including two autosomal-dominant mutants which have been associated with bladder defects (D3N and G143S), two autosomal-dominant mutants which have not been associated with bladder defects (G2V and I130T) and two autosomal- recessive mutants (R33X and R76H). Collectively, we revealed no differences in the molecular or Cx43 channel function of the bladder disease -associated or -unassociated mutants suggesting that …

Class Differences In Self-Rated Health: An International Comparison, Kayla Lynn Baumgartner

Digitized Theses

This paper analyzes the extent to which social class influences perceptions of health among Canadians and Americans. Self-rated health (SRH) is a valid predictor of morbidity and mortality, but what is not known is whether there are social class differences in the overlap between more objective indicators of health, such as the presence of disease or activity limitations, and subjective reports such as SRH. In this analysis I use the Joint Canada/United States Survey of health to assess whether, within categories of SRH, lower class individuals fare worse on objective health indicators than upper class individuals. I use cross-tabular analysis …

Clinical Reasoning Skills Of Post Graduate Physical Therapists Enrolled In A Distributed Education Program, Anne Elizabeth Edgell Kennedy

Digitized Theses

To determine if online learning enriches the clinical reasoning (CR) skills of advanced practice physical therapists (PTs). CR was measured in 26 PTs enrolled in a one year, course-based, masters program delivered using distributed learning including computer-based online courses (UWO). Outcomes were compared to IB PTs who sought the same credentials (FCAMPT) via a traditional face-to-face continuing education program. Bloom's Taxonomy Scale (BTS) was developed and used to evaluate CR in UWO students during two online discussion forums (ODF). The highest BTS score was in a medium learning level (application) and few students exhibited higher levels of learning (analysis & …

Voltage-Sensitive Dye Imaging Of Rat Piriform Cortex Before And After Kindling, Zeinab Biriandian

Digitized Theses

To determine the role of inhibitory cells in the propagation of activity in the rat piriform cortex (PC) before and after kindling, we used voltage-sensitive dye imaging technique to follow the membrane potential changes in three layers of the PC after stimulating the lateral olfactory tract (LOT) with beta and gamma frequencies. Stimulation of LOT was followed by propagation of excitatory (in layer II) and inhibitory responses (in layer III) through the PC. Decreasing the inhibition by applying gabazine, a GABAa- receptor antagonist, decreased the inhibitory responses and increased the excitatory responses in the control rats; however, it did not …

Primary Health Care Service Use Among Women Who Have Recently Left An Abusive Partner: Income And Racialization, Unmet Need, Fit Of Service, And Health, Marieka T. Stam

Digitized Theses

Primary health care (PHC) services can improve the health of women who have recently left an abusive partner. Yet, women’s ability to access and benefit from PHC services may be shaped by intersecting social locations, particularly income level and racialization. The purpose of this study was to examine whether differences in income and racialization, among women who had recently left an abusive partner, were associated with differences in PHC unmet need and fit of services, as well as to mental and physical health. A quantitative secondary analysis of data from the Canadian Women’s Health Effects Study (n = 286) was …

The Effect Of Connexin43 On The Development Of Skeletal Muscle Using Cell And Animal Models Of Oculodentodigital Dysplasia, Pasquale Vecchio

Digitized Theses

Skeletal muscle development involves the differentiation of myoblasts into myotubes; likely involving connexins (Cx) and the gap junctional exchange of secondary messengers and metabolites. Many patients with oculodentodigital dysplasia (ODDD), a rare primarily autosomal dominant disease caused by mutations in the gene encoding Cx43, become less ambulatory with aging and exhibit symptoms that may reflect defects in skeletal muscle development, maintenance, and repair. In this study, the role of Cx43 in skeletal muscle development was examined in differentiation-competent L6 myoblasts and two ODDD- linked Cx43-mutant mouse lines. Undifferentiated L6 myoblasts exhibited high levels of Cx43-based gap junctions which were inhibited …

Testing The Efficacy Of Aspartic Acid Racemization For Aging Adult Human Skeletal Remains, Mathew Teeter

Digitized Theses

Few problems have confounded bioarchaeological research as that of aging older (> 40 years) adult human skeletons. Researchers have targeted virtually every area of the skeleton and dentition in order to develop sequences of morphological and microscopic changes that can be correlated with chronological age. The key problem is that the morphological and microscopic changes are more variable with increasing age and this variance reduces their correlation with chronological years. In the past three decades molecular research has impacted virtually every research area in bioarchaeology except aging. The main objective of this thesis is to test aspartic acid racemization in …

The Effects Of A Peer Modeling Intervention On Aerobic Fitness Parameters And Self-Efficacy In Obese Adolescents, Stefanie De Jesus

Digitized Theses

The objective of this study was to examine the effect of a peer modeling intervention on

cardiorespiratory fitness performance and task self-efficacy in obese youth completing a maximal incremental treadmill test. Forty-nine obese youth (male = 26, BMI > 95th percentile for age and gender; 10 to 17 years of age) were randomized to an experimental group (n = 25) which received a peer modeling intervention or to an attention control group. The outcome variables were physical fitness (peak VO2, heart rate, duration, respiratory exchange ratio, rating of perceived exertion) and task self-efficacy. Observing the peer modeling intervention was not associated …

Mechanisms Underlying The Disruption Of Prepulse Inhibition By Nmdar Antagonists, Bridget C. Valsamis

Digitized Theses

Prepulse inhibition (PPI) of the acoustic startle response is a preattentive process disrupted in schizophrenia. NMDAR-antagonist induced PPI disruption has become a prevalent pharmacological model, however knowledge of the mechanism underlying NMDAR-antagonist induced PPI deficits (NAlPdef) remains incomplete. This work aims to examine the roles of NMDAR subtypes in the medial prefrontal cortex (mPFC) and the caudal pontine reticular nucleus (PnC) in NAlPdef in rats, and the effects of NMDAR antagonists on PPI and startle reactivity over the diurnal cycle. Results indicate that neither the PnC nor the diurnal cycle play a role in the mechanism underlying NAlPdef. However, microinjections …

Experimental Analysis Of The Effect Of Porosity And Primary Process Parameters On The Cutting Forces During Micromilling Of Titanium Foams, Mohammadmehdi Abolqhasemi Fakhri

Digitized Theses

Over the recent years, porous titanium foam became a common material in biomedical applications. Since modem near-net shape technologies are still unable to achieve the desired final shape of the end product, secondary machining operations like, for instance, micromilling are currently regarded as viable manufacturing options. However, a significant lack of information exists on micromilling of porous materials. The main goal of this study was to investigate experimentally the extent of correlation between porosity and cutting forces in the context of porous titanium foam micromilling. The porosity-cutting force interplay was assessed by means of statistical metrics and the effect of …

Exploring Formal Dementia Care Among First Nations In Southwestern Ontario: A Grounded Theory Study, Sara A. Finkelstein

Digitized Theses

This research aimed to understand how formal dementia care is being provided to First Nations communities. This was achieved by conducting in-depth interviews with healthcare providers and then qualitatively analyzing the data using a constructivist grounded theory approach. Results indicated that numerous barriers impede dementia care delivery, including lacking resources, difficulties collaborating among healthcare providers, encountering mistrust, and persons with dementia (PWD) not accessing care. However, numerous care strategies were identified, many of which serve to directly overcome these barriers. Many aspects of care delivery hinged upon effective knowledge sharing between healthcare providers, PWD, informal care providers, and the First …

Embodied Political Ecologies Of Health: A Case Study Of Alcohol And Infectious Disease In The Upper West Region Of Ghana, Joshua Kane Tobias

Digitized Theses

This research is a case study informed by qualitative methodologies examining perceptions of the misuse of an unregistered gin {akpeteshie), and it's role within the promulgation of hepatitis b in the Upper West Region of Ghana. Four research objectives are addressed: 1) to describe the nature of alcohol use among adults; 2) to explore local perceptions about hepatitis b held by adults in the region; 3) to examine the nature of health accessibility in the region; and, 4) to examine the links between alcohol use and the spread of hepatitis b, including the social­ environmental processes that underwrite these links. …

Development And Validation Of A Developmentally-Sensitive Task For The Induction Of Stress In Preschool-Aged Children, Katie R. Kryski

Digitized Theses

This study examined the validity of a novel task developed to elicit cortisol reactivity in a group of 215 preschool-aged children. Children participated in a standardized stress task during a home visit. The task was videorecorded for coding of child expressions of positive and negative emotions. Salivary cortisol samples were obtained at baseline and 10,20, 30,40, and 50 minutes post-stress. Statistically significant increases in cortisol levels from baseline were found followed by a significant decline defining a quadratic function. Children exhibited a significant increase in negative emotions and a decrease in positive emotions from baseline to the stressful portion of …

A Survey Of Health-Related Services In Ontario’S Youth Custody Facilities, Lisa S. Cossy

Digitized Theses

This survey collected information on the nature and extent of health-related services in Ontario’s youth custody facilities and examined how the services provided compare with standards recommended by the Canadian Paediatric Society and the World Health Organization for the health care of youth in custodial facilities. The results reveal that the facilities appear to be observing most of the recommendations from the Canadian Paediatric Society and the World Health Organization. There is considerable variation in the services provided across the facilities, and secure custody facilities have a greater variety of services available. Service provision appears to be related to a …

Surface Modification By Fluorocarbon Plasma Deposition For Microscale Cellular Patterning, Amanda Marilyn Leclair

Digitized Theses

Cell micropatterning technology has made significant advances in recent years towards the miniaturization and organization of traditional cell culture systems. Surfaces are precisely engineered to present spatially controlled biological cues that direct cells into patterns. Large populations of living cells can therefore be probed under a variety of environments, and has inspired investigations in areas such as cell biology, cell-based biosensors, and tissue engineering. Herein, surface modification techniques were employed to chemically pattern transparent glass substrates and the biological response was assessed. The plasma deposition of a cell-inhibiting fluoropolymer material combined with photolithographic patterning generated a transparent substrate with cell …

A Biomechanical Explanation For Convergent Head Movements Evoked By Stimulation Of The Primate Supplementary Eye Fields, Michael Allan Pace

Digitized Theses

Cortical microstimulation has played an important role in the investigation of movement coding in the frontal and supplementary eye fields (FEF and SEF). Recent evidence has shown that microstimulation of the SEF produces eye head gaze shifts whose kinematics depend on initial position. Across different stimulation sites in the

SEF, evoked movements converge in a variety of reference frames, possibly reflecting the SEF’s role in complex sensory-motor transformations. Here, we examine neck muscle activity evoked by SEF stimulation while monkeys attained a range of different initial positions through electromyographic (EMG) recordings of the neck muscles. A similar approach targeting the …

Analysis Of The Elastic Field In Functionally Graded Materials, Mohsen Mohammadi

Digitized Theses

In this thesis, the elastic field in circular beams and pipes made of functionally graded materials is considered. The following aspects are presented

First, the thermoelastic stress field in a functionally graded curved beam, where the elastic stiffness varies in the radial direction, is considered. An analytical solution is obtained where the radial variation of the stiffness is represented by a fairly general form. The stress fields corresponding to two different cases for the elastic properties are examined. The flexural stress in the curved beam is then compared with that of a ring. A relatively simple ap­ proximate solution is …

Mri Investigation Of Computer Users With And Without Chronic Wrist Pain, Ronald A. Burgess

Digitized Theses

Epidemiological studies have demonstrated a link between repetitive work and upper extremity musculoskeletal disorders (UEMSD), but the issue of causality remains controversial. Studies have shown an association between restricted wrist range of motion (ROM) and UEMSD in computer users. These restrictions were attributed to increased antagonist muscle tension. The first objective of this thesis was to compare wrist flexion ROM in computer users with UEMSD versus asymptomatic individuals with minimal computer exposure. The UEMSD group exhibited significantly reduced wrist flexion compared to controls. Measures of flexion with a supine forearm posture reduced wrist flexion in both groups, but the reduction …

Nicotinic Mechanisms Mediating Prepulse Inhibition Of The Acoustic Startle Response (Spine Title: Nicotinic Mechanisms Mediating Ppi Of The Startle Response), Tyler Kennedy Brown

Digitized Theses

Prepulse inhibition (PP1) is the attenuation of a startle response brought-on by a non-startling sensory stimulus (prepulse) presented 5-1000ms before the startle-evoking stimulus. It is a measure of sensory gating that is seen disrupted in schizophrenia, and other mental disorders. Nicotinic acetylcholine receptors (nAChRs) have been implicated in PPI of acoustic startle at both a systemic level and at the level in which the primary startle pathway can receive modulatory input - the caudal pontine reticular nucleus (PnC). This research will help clarify the role that nicotine plays in PPI at both a systemic level and at a level of …

Defining A Hair Mercury Loael For Neurotoxic Risk To The Unborn Child Through Maternal Fish Consumption, Katherine Schoeman

Digitized Theses

Methylmercury, whose primary source of exposure is via maternal fish consumption, can adversely affect human fetal neurodevelopment. The objectives of this diesis were threefold: 1) To systematically review the evidence of neurodevelopmental risks to the fetus from maternal fish consumption, to define a Lowest Observable Adverse Effect Level (LOAEL); 2) To measure mercury in hair of several groups including women of reproductive age, to define the proportion reaching this LOAEL; and 3) To investigate their perception of risk. We defined our LOAEL at 0.3pg/g maternal hair mercury. The Japanese population were the heaviest fish consumers, reflected by their high hair …

Development Of The Reagents And Protocols Necessary To Elucidate The Bsp-Binding Region Of Type I Collagen, Aaron Langdon

Digitized Theses

Bone sialoprotein, because of its affinity for the triple-helical type I collagen molecule and increased HA-nucleation potency upon binding collagen in vitro, is postulated to interact with type I collagen in vivo to initiate bone formation. Although the collagen-binding region of BSP has been located, the area of collagen involved in this interaction remains unknown. Through chemically cross-linking BSP to type I collagen, this region can be precisely mapped. The purpose of this study is to develop the reagents and protocols necessary for the covalent attachment of BSP to collagen, thereby creating

the possibility of locating the BSP-binding region of …