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Characterization Of The Circadian Properties Of Runt-Related Transcription Factor 2 (Runx2) And Its Role In The Suprachiasmatic Nucleus, Meghan E. Reale

Electronic Thesis and Dissertation Repository

Circadian rhythms orchestrate physiological, behavioral and cognitive processes in order to anticipate and adapt organisms to key environmental cues. These endogenously driven oscillations are generated by a network of interlocked auto-regulatory transcriptional-translational feedback loops driven forward by the Bmal1/Clock heterodimer transcription factor. Given the ubiquitous and dynamic quality of circadian rhythms, the identification of factors involved in the coordination and regulation of the endogenous oscillations is central in broadening our understanding of biological timing systems. In an examination of gene expression in the mammalian central circadian pacemaker, the hypothalamic suprachiasmatic nucleus (SCN), revealed a previously unreported rhythmic expression of runt-related …

Upheaval Buckling Of Offshore Pipelines In Homogeneous And Layered Soils, Porang Deljoui

Electronic Thesis and Dissertation Repository

Offshore oil and gas pipelines are commonly buried below the seabed to provide environmental stability and protection. Many of these pipelines are prone to upheaval buckling following burial. Soil failure mechanisms can extend to the surface (shallow) or remain localised within the soil body (deep); the exact conditions that cause this transition are currently unclear. In very weak soils, rock fill or sand berms are added to the surface of the completed trench after burial, to increase the required pull-out capacity. Despite a relatively large body of research existing in the literature, much confusion still exists as to the appropriate …

Peptide-Mediated Targeting Of Angiogenesis For Molecular Imaging And Treatment Of Cancer, Choi-Fong Cho

Electronic Thesis and Dissertation Repository

The development of screening approaches to identify novel affinity ligands has paved the way for a new generation of molecular targeted nanomedicines. To identify novel targeting ligands, several studies have demonstrated the advantages in screening one-bead-one-compound (OBOC) libraries. Conventional methods typically bias the display of the target protein to ligands during the screening process. We have developed an unbiased multiplex ‘beads on a bead’ strategy to isolate, characterize, and validate high affinity ligands from OBOC libraries. In addition, due to the advantages associated with screening OBOC libraries directly against living cells, we sought to combine cell-based screen methods with automated …

Properties And Applications Of Sensory Outcome Measures In Carpal Tunnel Syndrome, Derek Km Cheung

Electronic Thesis and Dissertation Repository

This thesis aimed to determine the psychometric properties and applications of sensory threshold tools and outcome measures in patients with Carpal Tunnel Syndrome (CTS). The first chapter is a psychometric study that defines clinically important difference (CID), construct validity and responsiveness of touch and vibration threshold tools and in the Symptoms Severity Scale (SSS). The study found the CID for the PSSD and for the SSS was 0.15g/mm² and 0.50 respectively. The study also found that the Vibrometer was more representative of hand function and responsive compared PSSD. The second objective of this thesis was to determine the feasibility …

Reduced Translocation Of Cadmium From Roots Is Associated With Increased Production Of Phytochelatins And Their Precursors, Mst. Fardausi Akhter, Brian Mcgarvey, Sheila Macfie

Biology Publications

Cadmium (Cd) is a non-essential trace element and its environmental concentrations are approaching toxic levels, especially in some agricultural soils. Understanding how and where Cd is stored in plants is important for ensuring food safety. In this study, we examined two plant species that differ in the distribution of Cd among roots and leaves. Lettuce and barley were grown in nutrient solution under two conditions: chronic (4 weeks) exposure to a low, environmentally relevant concentration (1.0 μM) of Cd and acute (1 h) exposure to a high concentration (5.0 mM) of Cd. Seedlings grown in solution containing 1.0 μM CdCl …

Because I Am Not Here, Selected Second Life-Based Art Case Studies. Subjectivity, Autoempathy And Virtual World Aesthetics, Francisco Gerardo Toledo Ramírez

Electronic Thesis and Dissertation Repository

Second Life is a virtual world accessible through the Internet in which users create objects and spaces, and interact socially through 3D avatars. Certain artists use the platform as a medium for art creation, using the aesthetic, spatial, temporal and technological features of SL as raw material. Code and scripts applied to animate and manipulate objects, avatars and spaces are important in this sense. These artists, their avatars and artwork in SL are at the centre of my research questions: what does virtual existence mean and what is its purpose when stemming from aesthetic exchange in SL?

Through a qualitative …

The Eshift Model Of Care: Informal Caregivers' Experience Of Caring For A Family Member Who Received Palliative Care At Home, Ashley Ralph

Electronic Thesis and Dissertation Repository

Amidst concerns about the capacity to meet the care needs of community dwelling clients, the South West Community Care Access Centre in London, Ontario piloted a new model of home care delivery to palliative care clients. The purpose of this interpretive description study was to describe the experiences of informal caregivers who have lived with and cared for a family member who received palliative care as part of the eShift model of home care. In this study, eight participants were purposively sampled and narrative data were collected through individual, audio-taped interviews using a semi-structured interview guide. The analysis and interpretation …

Detection And Mapping Of Phragmites Australis Using High Resolution Multispectral And Hyperspectral Satellite Imagery, Nicholas J. Lantz

Electronic Thesis and Dissertation Repository

Mapping invasive plant species is important to establish an invasion baseline, monitor plant propagation, and to implement an effective plan to deal with the invasion. In this thesis, methods are proposed to map invasive Phragmites australis in a Great Lakes coastal wetland. Chapter 2 presents an object-based Phragmites extraction method using Worldview-2 high-spatial-resolution satellite imagery. For the 4024 ha study area at Walpole Island,Ontario, 94% overall accuracy was achieved.

Chapter 3 uses CHRIS PROBA hyperspectral satellite imagery for mapping the pixel abundance of Phragmites using a spectral mixture analysis method. An evaluation method was developed to assess the accuracy of …

Impact Of Bioparticle Recirculation In A Circulating Fluidized Bed Biofilm Reactor On Simultaneous Organic And Nitrogen Removal, Ming Li

Electronic Thesis and Dissertation Repository

The Circulating Fluidized Bed Biofilm Reactor (CFBBR), a bioparticle technology designed for biological nutrient removal, has been implemented to achieve considerable biodegradation efficiency and low sludge production, compared with activated sludge system and typical biofilm technology. The inherent advantages of bioparticle technology are enhanced substantially by the CFBBR, for example, decoupling of hydraulic retention time (HRT) from solids retention time (SRT), large specific surface area, ideal conditions for biofilm ecosystem.

In this work, bioparticle recirculation, as a novel control method for bioparticle system, was demonstrated in CFBBRs. To verify the impact of bioparticle recirculation on the reactor performance, bio-kinetics and …

Reliability And Validity Of Knee Moments: 3d Gait Analysis In Subjects With And Without Knee Osteoarthritis, Sara E. Richardson

Electronic Thesis and Dissertation Repository

Quantifying the reliability and validity of gait data in patients with knee osteoarthritis is required to more confidently evaluate effects of interventions and identify potential responders. 109 patients after high tibial osteotomy underwent 3-dimensional gait analysis consisting of four walking trials to calculate the external knee moments in three anatomical planes. The first two trials were compared to the second two trials to evaluate within-session test re-test reliability. 61 patients were matched to 61 healthy controls of similar age, sex and body mass index. Intraclass correlation coefficients were very high, ranging from 0.93 for peak knee adduction moment to 0.84 …

Arctic Cold Spring Mineralogy As An Indicator Of Spring Deposits, Water, And Habitable Environments On Mars, Melissa M. Battler

Electronic Thesis and Dissertation Repository

Springs exist in many terrestrial settings and have supported microbial communities throughout Earth’s history. There is mounting evidence for spring deposits on Mars from Noachian age to present, implying that water may be circulating in Mars’ subsurface despite current cold, arid conditions. Current datasets for most of Mars are limited to mineralogy via orbital spectroscopy and geomorphology from visual imagery and laser altimetry. Much is known about terrestrial spring morphology, but few springs exist in Mars analogue settings, and of those, few have been investigated for mineralogy. This study reports on two sets of cold spring sites in the Canadian …

Development Of A Compact Piezoworm Actuator For Mr Guided Medical Procedures, Khaled El Bannan

Electronic Thesis and Dissertation Repository

In this research, a novel piezoelectric actuator was developed to operate safely inside the magnetic resonance imaging (MRI) machine. The actuator based on novel design that generates linear and rotary motion simultaneously for higher needle insertion accuracy. One of the research main objectives is to aid in the selection of suitable materials for actuators used in this challenging environment. Usually only nonmagnetic materials are used in this extremely high magnetic environment. These materials are classified as MRI compatible materials and are selected to avoid hazardous conditions and image quality degradation. But unfortunately many inert materials to the magnetic field do …

Bf2obn∙Oet2: A Novel Lewis Acid And Its Use In A Regio- And Stereo-Selective Opening Of Trisubstituted Epoxides And Its Application Towards Amphidinolide C, Nicholas A. Morra, Brian Pagenkopf

Chemistry Publications

The generation of a new Lewis acid (BF2OBn·OEt2) has been reported, and its usefulness has been demonstrated in the regio- and stereoselective ring-opening of trisubstituted epoxides. This Lewis acid is one in a series of new Lewis acids generated from BF3·OEt2 that display varying levels of Lewis acidity. When paired with a modified Shi epoxidation protocol, highly functionalized propionate units, such as those found in a wide variety of natural products, can be accessed. In conjunction with a Mukaiyama oxidative cyclization employing our second generation catalyst Co(nmp)2, this procedure ultimately culminated in the shortest and highest yielding route towards the …

Topographic Influences On Trends And Cycles In Nutrient Export From Forested Catchments On The Precambrian Shield, Samson G. Mengistu

Electronic Thesis and Dissertation Repository

This dissertation explored topographic controls on spatial and temporal patterns in water yield and nutrient (carbon, nitrogen and phosphorus) export from forested headwater catchments in the Turkey Lakes Watershed in central Ontario, where other factors contributing to differences in water yield and nutrient export, including climate, geology, forest, and soils, are relatively constant. Topographic characteristics, including (a) hydrological flushing potential (expansion of water table into nitrate-N producing areas); (b) hydrological storage potential (area of wetlands, which can alternatively allow water and nutrients to bypass wetlands when storage capacity is filled with water or to trap them when not filled); and …

Simultaneous Radar And Video Meteors, Robert J. Weryk

Electronic Thesis and Dissertation Repository

The goal of this thesis is to better understand the physical and chemical properties of meteoroids by using simultaneous radar and video observations of meteors. The Canadian Meteor Orbit Radar (CMOR) and several Gen-III image-intensified CCD cameras were used to measure common meteors and validate metric errors determined through Monte Carlo modelling and to relate radar electron line density (q) to video photon radiant power (I). By adopting an ionisation coefficient from Jones (1997) and using recorded measurements of q/I, a corresponding estimate of the fraction of meteoroid kinetic energy loss converted into light (luminous efficiency) was found.

It was …

Production Of Bio-Coal And Activated Carbon From Biomass, Diana C. Cruz

Electronic Thesis and Dissertation Repository

The slow pyrolysis of different biomasses (maple wood, birch bark, switch grass, coffee pulp and corn stalk) was studied with the aim to produce a solid pyrolysis product (bio-coal) with promising properties and potential for use in traditional fossil-coal applications. Batch pyrolysis experiments were conducted in a Mechanically Fluidized Reactor (MFR) at temperatures ranging from 143 to 665 ^oC, which includes the torrefaction temperature range (200-300 ^oC). The effects of temperature and holding time on bio-coal mass yields were determined. The bio-coals were characterized in detail and a highly-controlled study on bio-coal hygroscopicity is presented. Optimal conditions for …

Fractional Condensation Of Bio-Oil Vapors, Akhil Tumbalam Gooty

Electronic Thesis and Dissertation Repository

The research project described in this thesis deals with an investigation on the fractional condensation of bio-oil vapors to improve the separation of some of the key components of the bio-oil and, consequently, improve the properties and the value of each of the separated product streams.

In the first part, the separation of a mixture of three model compounds of bio-oil from a vapor and carrier gas stream was investigated with the help of a series of three condensers maintained at different temperatures. The practical performance of the fractional condensation train was improved by comparing the experimental results with the …

Experimental Investigation Of The Fluid Temperature Field And The Thermal Performance Of Insert Devices In A Flat-Plate Solar Collector, Gurveer Singh Sandhu

Electronic Thesis and Dissertation Repository

An experimental study on the thermal flow behavior inside a flat-plate collector and the impact of insert devices (passive heat transfer enhancement techniques) on the thermal performance of the collector is presented. Temperature fields were obtained for different Reynolds numbers (250-650) and at different inclination angles of the collector. The results show that a stratified flow is developed inside the collector and the warmer fluid restricts itself to the upper portion of the collector only. Various new configurations of the conventional insert devices were tested over a wide range of Reynolds number (200-8000). Comparison of these devices show that in …

Investigating Personality Vulnerability To Suicide Ideation In Community-Residing Older Adults, James Andrew Mcclure

Electronic Thesis and Dissertation Repository

This study assessed associations between suicide ideation and personality characteristics in a sample of community-residing adults 65 years of age and older. Measures of personality, suicide ideation, and depression were administered at two time points 6-12 months apart. Multiple linear regression analyses were employed to investigate cross-sectional and longitudinal associations between personality characteristics and suicide ideation. A total of 106 older adults (mean age=74.2 years, SD=5.8, including 78 women) completed both phases of the study. The majority of participants included in this study were relatively emotionally and psychologically healthy. Within this sample of older adults, more severe suicide ideations was …

An Experimental Investigation Into The Relationship Between Process Variables And Forming Conditions During Splined Mandrel Flow Forming Operations, Brandon C. Vriens

Electronic Thesis and Dissertation Repository

Splined Mandrel Flow Forming (SMFF) is an effective method for fabricating a variety of internally-ribbed cylindrical parts. The process is, however, prone to premature failure of the splined mandrels and this is thought to be related to the magnitude of the forming forces exerted by the forming rollers on the mandrel splines. In this thesis an experimentation-based approach is used to investigate the effects of critical process parameters; namely, Inter-roller offset of the X1-X2 forming rollers, Oa, roller inclination angle, roller nose radius, r0, forming roller feed rate and mandrel rotational speed, on forming forces exerted on an AISI 1020 …

Online Social Breast-Working: Representations Of Breast Milk Sharing In The 21st Century, Cari L. Rotstein

Electronic Thesis and Dissertation Repository

This thesis explores the controversial subject of online breast milk sharing through the lens of Social Positioning Theory and interpretative repertoire analysis. I examine medical statements, Facebook wall posts on the Human Milk 4 Human Babies Global group and selected Canadian provincial groups, as well as a selection of Canadian print news media coverage pertaining to milk sharing to discover how this practice is discussed. I argue that the medical literature discusses milk sharing as unsafe, informal, and a generally unacceptable means of obtaining breast milk, whereas the HM4HB group members discuss it as a safe, intimate experience between donor …

The Impact Of The Neuropeptide Y System On The Progression Of Breast Cancer, Philip J. Medeiros

Electronic Thesis and Dissertation Repository

Chronic stress is associated with elevated levels of sympathetic neurotransmitter release and immunosuppression. A growing body of evidence suggests that stress-related factors may contribute to the initiation, development and progression of breast cancer. Neuropeptide Y (NPY) has recently been determined as such a factor, however few investigations have addressed the functional effects of NPY on breast cells and tumors. Thus, the overall objective of this thesis was to elucidate the mechanisms by which NPY may contribute to the disease. Using the 4T1 murine breast cancer model, we began by first characterizing NPY receptor expression in cancer cells and tumors. Y1R, …

Clinical Instructors' Perceptions Of Structural And Psychological Empowerment In Academic Nursing Environments, Sandra E. Wiens

Electronic Thesis and Dissertation Repository

ABSTRACT

The study purpose was to explore clinical instructors’ perceptions of empowerment in academic nursing environments. Clinical instructors (CIs), often part-time faculty, facilitate learning in professional practice environments. However, they also need to function within the academic environment to learn about the curriculum and how students are to be evaluated.

The qualitative description method was used to obtain a broad understanding of CIs’ empowerment experiences and to interpret their perceptions with the framework of Kanter’s (1977, 1993) structural empowerment and Spreitzer’s (1995) psychological empowerment theories. Eight CIs from two nursing programs were interviewed.

All empowerment components were important in CIs’ …

Investigating The Therapeutic Potential Of Salivary Proteins For Oral Diseases, Dusa Vukosavljevic

Electronic Thesis and Dissertation Repository

ABSTRACT

Saliva is responsible for the formation of the acquired enamel pellicle (AEP), a protein

integument formed as a result of selective adsorption of salivary proteins to the enamel

surface. The AEP demonstrates an important role for modulating dental erosion as a

result of its physical properties, along with its salivary and exogenous protein

composition (Chapter 2). In addition, individual proteins that comprise the AEP have

important physiological functions. Histatin 5 (H5) has potent antifungal effect against C.

albicans, the yeast responsible for the initiation of oral candidiasis. We designed an in

vitro model and found, for the first time, …

A Treeboost Model For Software Effort Estimation Based On Use Case Points, Luiz Fernando Capretz, Ali Bou Nassif

Electrical and Computer Engineering Publications

Software effort prediction is an important task in the software development life cycle. Many models including regression models, machine learning models, algorithmic models, expert judgment and estimation by analogy have been widely used to estimate software effort and cost. In this work, a Treeboost (Stochastic Gradient Boosting) model is put forward to predict software effort based on the Use Case Point method. The inputs of the model include software size in use case points, productivity and complexity. A multiple linear regression model was created and the Treeboost model was evaluated against the multiple linear regression model, as well as the …

Preventing Long-Term Risk Of Obesity For Two Generations: Prenatal Physical Activity Is Part Of The Puzzle, Stephanie May Ruchat, Michelle F. Mottola

Paediatrics Publications

Background. The period surrounding pregnancy has been identified as a risk period for overweight/obesity in both mother and child because of excessive gestational weight gain (GWG). The promotion of a healthy GWG is therefore of paramount importance in the context of the prevention of obesity in the current and next generations. Objective. To provide a comprehensive overview of the effect of prenatal physical activity interventions, alone or in combination with nutritional counselling, on GWG and to address whether preventing excessive GWG decreases the incidence of infant high birth weight and/or postpartum weight retention. Method. A search of the PubMed database …

In Utero Programming Of Later Adiposity: The Role Of Fetal Growth Restriction, Ousseynou Sarr, Kaiping Yang, Timothy R.H. Regnault

Paediatrics Publications

Intrauterine growth restriction (IUGR) is strongly associated with obesity in adult life. The mechanisms contributing to the onset of IUGR-associated adult obesity have been studied in animal models and humans, where changes in fetal adipose tissue development, hormone levels and epigenome have been identified as principal areas of alteration leading to later life obesity. Following an adverse in utero development, IUGR fetuses display increased lipogenic and adipogenic capacity in adipocytes, hypoleptinemia, altered glucocorticoid signalling, and chromatin remodelling, which subsequently all contribute to an increased later life obesity risk. Data suggest that many of these changes result from an enhanced activity …

Tourists' Perceptions Of Aboriginal Heritage Souvenirs, Janet Chang, Geoffrey Wall, Jul-Cheng (Richard) Hung

Aboriginal Policy Research Consortium International (APRCi)

Heritage souvenirs are an indispensable part of indigenous tourism and the authenticity of indigenous heritage is a vital aspect of such tourism. This study adopts a mixed methods approach to explore the perceived authenticity of glass bead souvenirs of the Paiwan Tribe in Pintung County, Taiwan. The study explores differences in the evaluations of authenticity among stakeholders and the factors that influence perceptions of authen- ticity. An understanding of tourists’ perceptions of indigenous heritage offers valuable information for the creation of indigenous souvenirs and for reviving the promotion of indigenous culture.

Conserved Region 3 Of Human Papillomavirus 16 E7 Contributes To Deregulation Of The Retinoblastoma Tumor Suppressor, Biljana Todorovic, Katherine Hung, Paola Massimi, Nikita Avvakumov, Frederick A. Dick, Gary S. Shaw, Lawrence Banks, Joe S. Mymryk

Paediatrics Publications

The human papillomavirus (HPV) E7 oncoprotein binds cellular factors, preventing or retargeting their function and thereby making the infected cell conducive for viral replication. A key target of E7 is the product of the retinoblastoma susceptibility locus (pRb). This interaction results in the release of E2F transcription factors and drives the host cell into the S phase of the cell cycle. E7 binds pRb via a high-affinity binding site in conserved region 2 (CR2) and also targets a portion of cellular pRb for degradation via the proteasome. Evidence suggests that a secondary binding site exists in CR3, and that this …

The Dynamics Of Entrepreneurship: Hysteresis, Business Cycles And Government Policy, Emilio Congregado, Antonio A. Golpe, Simon C. Parker

Business Publications

This paper estimates an unobserved components model to explore the macro dynamics of entrepreneurship in Spain and the US. We ask whether entrepreneurship exhibits hysteresis, defined as a macro dynamic structure in which business cycle fluctuations have persistent effects on the natural rate of entrepreneurship. We find evidence of hysteresis in Spain, but not the US, while in both countries business cycle output variations significantly affect future rates of entrepreneurship. The article discusses implications of the findings for the design of entrepreneurship policies.