VictorJuiz/thesis huggingface dataset:
The Effect of Salvia hispanica L. Seeds on Weight Loss in Overweight and Obese Individuals with Type 2 Diabetes Mellitus
Keywords: obesity
omega 3 fatty acids
type 2 diabetes
inflammation
nutrition
functional foods

There is growing interest in the potential role of omega-3/fibre-rich seeds in attenuating obesity and other cardiovascular disease (CVD) risk factors in individuals with type 2 diabetes mellitus (T2DM). Preliminary data suggests that consumption of white Salvia hispanica L. (Salba&reg;) seeds prolongs satiety and may aid weight loss. This randomized, double-blind, parallel study assessed the efficacy and safety of Salvia hispanica in overweight/obese individuals with T2DM on weight, body composition, glycemic control and other CVD risk factors. Fifty-eight participants consumed a hypocaloric diet including Salvia hispanica or an energy-and-fibre-matched control over 24 weeks. Greater reductions in weight, waist circumference and inflammation occurred in the Salvia hispanica group versus control. There were no significant between-group differences in safety parameters, glycemic control or other CVD risk factors. Salvia hispanica seeds may support weight loss in overweight/obese individuals with T2DM. Further research is needed to determine whether these effects are maintained.
Biodegradation of Dental Resin Composites and Adhesives by Streptococcus mutans: An in vitro Study
Keywords: Dental resin composites
Biodegradation

A major cause for dental resin composite restoration replacement is secondary caries attributed to Streptococcus mutans. Salivary esterases were shown to degrade resin composites. Hypothesis: S. mutans contain esterase activities that degrade dental resin composites and adhesives. Esterase activities of S. mutans were measured using synthetic substrates. Standardized specimens of resin composite (Z250), total-etch (Scotchbond-Multipurpose, SB), and self-etch (Easybond, EB) adhesives were incubated with S. mutans UA159 for up to 30 days. Quantification of a bisphenol-glycidyl-dimethacrylate (BisGMA)-derived biodegradation by-product, bishydroxy-propoxy-phenyl-propane (BisHPPP) was performed using high performance liquid chromatography. Results: S. mutans were shown to contain esterase activities in levels comparable to human saliva. A trend of increasing BisHPPP release throughout the incubation period was observed for all materials and was elevated in the presence of bacteria vs. control for EB and Z250 (p&lt;0.05) but not SB. Conclusion: biodegradation by cariogenic bacteria could compromise the resin-dentin interface and reduce the longevity of the restoration.
Development and Validation of an Experimental Apparatus for the Characterization of Soot in a Laminar Co-flow Diffusion Flame Using Laser-induced Incandescence
Keywords: Laser-Induced Incandescence
Soot
Atmospheric
Ethylene
Laminar
Co-flow
Diffusion flame

The current study represents the first application of commercial laser-induced incandescence (LII) instrumentation at the University of Toronto Combustion Research Laboratory, for the characterization of soot in atmospheric laminar co-flow diffusion flames. An experimental apparatus was designed to accommodate the optical diagnostic, and to provide the means to probe various regions of the flames. An experiment with a well-characterized non-smoking ethylene-air diffusion flame was carried out to validate the performance of the LII instrument. Three measurement heights were analyzed; those at 40, 50, and 60 mm above the fuel exit. The soot volume fraction results were found to be in good agreement with those from the literature. The highest value was found to be 8.3 ppm at a height of 40 mm. While the instrumentation could report primary particle diameters, it was determined from the validation trial that the results were still premature. Further work is needed to validate the results of the instrument, especially for the particle size data.
Tree Roots in Agroforestry: Evaluating Biomass and Distribution with Ground Penetrating Radar
Keywords: belowground biomass
tree-based intercropping
carbon concentration
fine roots

The root systems of five tree species (Populus deltoides × nigra clone DN-177, Juglans nigra, Quercus rubra, Picea abies, and Thuja occidentalis) are described following non-intrusive imaging using ground penetrating radar (GPR). This research aimed to 1) assess the utility of GPR for in situ root studies and 2) employ GPR to estimate tree root biomass and distribution in an agroforestry system in southern Ontario, Canada. The mean coarse root biomass estimated from GPR analysis was 54.1 ± 8.7 kg tree-1 (± S.E.; n=12), within 1 % of the mean coarse root biomass measured from matched excavations. The vertical distribution of detected roots varied among species, with T. occidentalis and P. abies roots concentrated in the top 20 cm and J. nigra and Q. rubra roots distinctly deeper. I evaluate these root systems based on their C storage potential and complementary root stratification with adjacent crops.
An Investigation of Nonlinear Control of Spacecraft Attitude
Keywords: H-infinity control theory
modified Rodrigues parameters
spacecraft attitude control
control theory

The design of controllers subject to the nonlinear H-infinity criterion is explored. The plants to be controlled are the attitude motion of spacecraft, subject to some disturbance torque. Two cases are considered: the regulation about an inertially-fixed direction, and an Earth-pointing spacecraft in a circular orbit, subject to the gravity-gradient torque. The spacecraft attitude is described using the modified Rodrigues parameters. A series of controllers are designed using the nonlinear H-infinity control criterion, and are subsequently generated using a Taylor series expansion to approximate solutions of the relevant Hamilton-Jacobi equations. The controllers are compared, using both input-output and initial condition simulations. A proof is used to demonstrate that the linearized controller solves the H-infinity control problem for the inertial pointing problem when describing the plant using the modified Rodrigues parameters.
Development of an Electrochemical Immunosensor for the Detection of HIV Antibodies Using Surface Modification of SU-8
Keywords: Immunosensor
Electrochemistry
HIV
Antibody
SU-8

The negative epoxy-based photoresist of SU-8 has a variety of applications within microelectromechanical systems (MEMS) and lab-on-a-chip systems. Herein, SU-8 was functionalized with antigenic peptides to HIV-1 gp41 or HIV-2 gp36 and the detection of antibody against HIV-1/2 was carried out by an electrochemical immunoassay combining an alkaline phosphatase conjugated secondary antibody and p-aminophenyl phosphate. The by- product of the reaction (p-aminophenol) was quantitated electrochemically using differential pulse voltammetry, and the current derived from the oxidation of the hydrolysis product increased linearly over a wide primary antibody concentration range (0.001 – 1 μg/mL), with a detection limit of 1 ng mL-1 (6.7 pM) for both HIV-1 and HIV-2. This level of sensitivity is clinically relevant, and feasibility of this approach for clinical sample testing was also evaluated with HIV clinical patient samples.
Design and Evaluation of a Context-aware User-interface for Patient Rooms
Keywords: User interface
patient room information
Human Computer Interface
Context awareness
Clinical Engineering
Health Informatics
Ethnographic design

The process of patient care relies on clinical data spread across specialized hospital departments. Powerful software is being designed to assimilate this disconnected patient data before treatment can be decided. However, these data are often presented to clinicians on interfaces that do not fit clinical workflows, leading to poor operational efficiency and increased patient safety risks. This project relies on ethnographic design methods to create evidence of clinician preferences pertaining to the presentation and collection of information on user interfaces in patient rooms. Using data gathered in clinical observation, a prototype interface was designed to enable doctors to conduct clinical tasks through a usable patient room interface. The prototype evaluation with doctors identified clinical tasks that are relevant in the patient room and provided insight into the perceived usability of such an interface. The evaluation sessions also elucidated on issues of patient-centeredness in technology design, effortless authentication and interface customizability.
The Inflammatory and Neuroanatomical Factors Involved in Post-stroke Depression
Keywords: post-stroke depression
kynurenine
inflammation
stroke
depression
neuroanatomy
neuroradiology
tryptophan
cytokine

This cross-sectional study examined neurobiologic correlates of depression in ischemic stroke patients. Depression severity was measured with a standardized scale (Center for Epidemiologic Studies Depression Scale; CES-D). Eighty-two patients (53.1% male, mean (± SD) age 71.9 ± 14.2 years, mean (± SD) National Institutes of Health Stroke Scale (NIHSS) score 4.6±4.7, mean (± SD) CES-D score 12.6 ± 10.8) were recruited. A linear regression controlling for age and stroke severity (NIHSS) determined that the kynurenine to tryptophan ratio (β= -0.105, p=0.369) was not significantly associated with CES-D (primary hypothesis) (overall model R2=0.069, F3,73=1.805, p=0.154). Secondary analyses suggested one instance of cytokines favouring inflammatory states in mild depressive symptomatology; IFN-Ɣ/IL-10 (OR, 2.17; 95% CI, 1.02-4.64, p=0.045). For the most part however, inclusion of cytokines and neuroimaging correlates such as atrophy, lesion location and white matter changes were non-significant. Longitudinal studies are necessary to identify the possible neurobiologic correlates of depressive symptoms post-stroke.
The Legal Protection of the Small Retailer in the Shopping Center
Keywords: Shopping Center
Leasing

The issue of the protection of the small retailers in shopping centers deserves to be addressed since those retailers do not always have the economical weight to negotiate their leases on an equal footing with their landlords. In Canada and France, this situation is not dealt the same way: where Canada relies on contractual freedom to balance the interests involved, France is very protective. This thesis aims to study and compare those two regimes and tries to determine whether small retailers need protection.
Domain-generality of Parietal Attentional Processes and their Implications for Old Age
Keywords: posterior parietal cortex
attention
memory
cognitive ageing

The posterior parietal cortex (PPC) has been reliably implicated in visuospatial attention, such that the dorsal regions (dPPC) are associated with voluntary ‘top-down’ attention, whereas the ventral regions (vPPC) are associated with automatic ‘bottom-up’ attentional processes. The Attention-to-Memory model (AtoM: Ciaramelli, Grady, & Moscovitch, 2008) has suggested that it also plays a similar role in memory retrieval, suggesting that the PPC mediates a domain-general attentional process. Furthermore, domain-generality of attentional processes may account for differences in perception and memory function accompanying old age. This study examined domain-generality by determining the shared variance in performance of tasks thought to recruit top-down and bottom-up attentional processes mediated across both domains. Results clearly suggested generality across domains in top-down processing; and in bottom-up processing, depending on its operationalization. Ageing was characterized by an absence of shared variance across domains and slower reaction times during bottom-up attentional reorienting only in perception.
A Glimpse into the Future? The Current, Potential, and Appropriate Role of Functional Magnetic Resonance Imaging (fMRI) Evidence as a Predictor of Dangerousness in the American Criminal Sentencing Context
Keywords: sentencing
neuroimaging

Research suggests there are neurological predictors of violence, such as brain function abnormalities most frequently displayed by violent offenders who may suffer from a psychological phenomenon termed &ldquo;psychopathy.&rdquo; Functional magnetic resonance imaging (fMRI) can detect signs of some of these brain abnormalities. Neurological markers of violence, evident in a convicted individual&rsquo;s fMRI results, could speak to that offender&rsquo;s tendency to act violently in the future. Can fMRI play a meaningful role in estimating recidivism rates and in sentencing? Even if fMRI evidence meets legal thresholds for use in sentencing, should it be employed in light of many concerns, such as reliability, as the implications of predicting an individual&rsquo;s dangerousness based on fMRI evidence are substantial, especially in the context of defendant rights. Moreover, neurological indicators of violence may undermine a holistic approach to sentencing that considers the convicted individual&rsquo;s particular story.
Telomerase as a Prognostic Marker and Therapeutic Target in Paediatric Ependymoma
Keywords: ependymoma
telomerase
Imetelstat
telomerase inhibition

Paediatric ependymomas are the third most common childhood brain cancer and represent a prognostic and therapeutic challenge. Previous evidence suggests that telomerase, a ribonucleoprotein critical in permitting limitless growth potential, may serve as both a prognostic marker and therapeutic target. Immunohistochemical analysis (n=198) and enzymatic detection (n=25) of telomerase was performed to determine prevalence and prognostic potential. The telomerase inhibitor Imetelstat was used to study telomerase inhibition in paediatric ependymoma cell lines, tumour initiating cells (TICs) and both subcutaneous and intracranial xenografts. Telomerase activity was detected in 76% of primary ependymomas and was associated with a reduced five-year progression-free survival (30% vs 75%). Telomerase inhibition in vitro resulted in shortened telomeres, increased senescence, growth inhibition and reduced self-renewal capacity. In vivo, Imetelstat shortened telomeres and reduced subcutaneous tumour volume by 40% compared to control mice. Therefore, telomerase may serve as an ideal prognostic marker and therapeutic target in paediatric ependymoma.
Coaches' Roles in Facilitating the Personal Development of Canadian Interuniversity Student-athletes
Keywords: Personal development
Canadian Interuniversity Sport (CIS)
Student-athlete
Coach

The purpose of this study was to investigate coaches’ perspectives on the personal development of student-athletes through interuniversity sport participation. More specifically, the ways in which coaches understand and facilitate athletes’ personal development were explored. Eight semi-structured interviews were conducted with male and female head coaches of Canadian Interuniversity Sport (CIS) programs. A qualitative approach, utilizing an inductive analysis of the data revealed: coaches’ difficulty in defining personal development and articulating the ways in which they facilitate opportunities for athletes’ personal development through sport; a lack of clarity of the methods used to measure athletes’ personal development; and the ensuing ramifications of university sport model reviews which are moving towards a high performance model of sport on athletes’ personal development. Findings from this study contribute knowledge and understanding of a previously little studied phenomenon – the personal development of student-athletes – and the perspectives from a relatively un-explored population, university head coaches.
High-Integration-Density Neural Interfaces for High-Spatial-Rrsolution Intracranial EEG Monitoring
Keywords: Neural Intarfaces
Integrated Circuit

This thesis presents two experimental microelectronic prototypes for neurophysiological applications. Both systems target diagnostics and treatment of neurological disorders, and they are experimentally validated in vivo by online intracranial EEG recording in freely moving rats. The first prototype is a 56-channel chopper-stabilized low-noise neural recording interface IC with programmable mixed-signal DC cancellation feedback, fabricated in a 0.13μm CMOS process. Each recording channel has a low-noise fully-differential amplifier, and a digital integrator and a delta-sigma DAC in the feedback to cancel DC offsets of up to ±50mV. Chopper stabilization technique is used to reduce the amplifier flicker noise. The recorded signals are digitized by 7 column-parallel SAR ADCs. The second prototype is a compact headset for multi-site neuromonitoring and neurostimulation in rodent brain. A stack of 2 mini-PCBs was designed and experimentally validated. It includes a previously fabricated 0.35μm CMOS recording and stimulation IC, a low-power FPGA, and the IC peripherals.
Characterization of Abuse Properties of the Anesthetic Propofol Using the Self-administration Paradigm in Rats
Keywords: propofol self-administration
fixed ratio schedule
substance abuse
acquisition
extinction
reinstatement

Propofol is a widely in use anesthetic drug. Propofol’s abuse liability has been supported by many case reports and a few animal studies. However, propofol’s reinforcing properties have not yet been investigated in-depth. In this study, multiple aspects of propofol’s abuse-related behaviour were investigated using the drug self-administration model in rats. METHODS: Rats were subjected to propofol self-administration under a fixed ratio 1 (FR1) schedule and different aspects of propofol self-administration behaviour including acquisition, maintenance of the behaviour under a higher ratio schedule, extinction and reinstatement were investigated. RESULTS: Rats acquired propofol self-administration under a FR1 schedule. The acquired behaviour was maintained under a FR2 schedule, showed a modest variation over a range of doses, and was extinguished upon substitution of vehicle for propofol, showing no reinstatement using a range of priming doses of propofol. CONCLUSION: Propofol has abuse potential showing modest reinforcing properties under our experimental conditions.
Sleep and Circadian Markers for Depression in Adolescence
Keywords: depression
adolescents
sleep

Early-onset major depressive disorder (MDD) is associated with significant morbidity in adolescence. The interview-dependent diagnostic process used in psychiatry leaves a subset of adolescents with MDD undiagnosed. Sleep disturbances are a central feature of depression and adolescence is a period of rapid change in sleep physiology. The aim of this study was to test physiological features of sleep and circadian rhythms as markers of adolescent MDD. Adolescents completed a two-week protocol that included a formal psychiatric interview, polysomnographic (PSG) assessment, actigraphy, salivary melatonin sampling, and holter monitoring. Depressed adolescents (n = 18) differed from controls (n = 15) on features of sleep macroarchitecture measured by PSG, and on autonomic nervous system functioning measured by 24-hour heart rate variability. Depressed adolescents had shorter REM latency and decreased stage 4 sleep. Adolescents with MDD also showed decreased parasympathetic activity over 24-hours and during the day, and decreased sympathetic activity during the night.
MEG Analysis of Temporal and Anatomical Neural Activation During False Belief Reasoning
Keywords: theory of mind
false belief
MEG
social cognition

We examined the spatiotemporal dynamics underlying the processing of a false belief task using magnetoencephalography (MEG). Twenty adults performed a false belief task adapted for MEG. Regions of interest were selected based on source analyses on the contrast between false and true belief, and MEG source time-course reconstructions were generated and analyzed to determine the temporal architecture of neural activations specific to false belief reasoning. We found frontal, temporal and parietal regions to activate during false belief processing, confirming prior findings. We also extend previous findings by adding information about the temporal profile of neural activity during theory of mind processing, an area lacking in the literature. We found that increased frontal activity began at 100 ms bilaterally, followed by parietal regions from 200 to 330 ms and temporal regions at 350 ms, at which point frontal activity became lateralized to the right hemisphere.
Optical Neural Imaging in Rodents using VCSELs
Keywords: Biomedical Imaging
VCSEL

Optical brain imaging is proven to be useful to understand brain function and morphology at cellular and network level. Different optical imaging modalities were developed over the years, with our group developing multi-modal simultaneous imaging using Vertical Cavity Surface Emitting Lasers (VCSELs). This thesis improves and demonstrates the applicability of the imaging system and adapts it to portable imaging. Specifically, it was found that using multiple exposures provide better flow measurements when compared to tracking measurements. An intrinsic parameter to monitor the state of the Blood Brain Barrier (BBB) was also discovered, proving more practical than previous fluorescence methods. We finally demonstrate initial results of imaging flow velocities and fluorescence in awake and moving rodents using VCSELs, achromatic doublets and a CMOS camera. Future work involves developing new prototypes of the portable system for imaging of disease states in awake animals and minimizing movement artefacts for oxygenation measurements.
Understanding the Effect of Wastewater Flocs Properties on UV Disinfection Kinetics
Keywords: Ultraviolet
Wastewater
UV Disinfection
Microbial Flocs

Wastewater microbial flocs can protect microorganisms from inactivation by UV light. This effect is detected as tailing at high UV doses in the UV dose response curve. A double-layer structure composed of an inner compact core surrounded by a loose outer layer was proposed by earlier studies to describe UV resistance of microbial flocs. Due to limited oxygen diffusion into the compact cores, the UV inactivation of compact cores and microbial flocs under anaerobic conditions needed to be addressed. The UV disinfection kinetics under anaerobic culturing condition was nearly identical to that of the aerobic study. Moreover, the role of iron concentration on the differences in the UV inactivation kinetics of flocs and cores was assessed. The increase in UV absorbance of floc material due to iron addition could dominate the UV disinfection kinetics of flocs and cores such that they exhibited similar UV disinfection kinetics.
Role of miRNAs in Translational Control of Human Apolipoprotein B-100 mRNA
Keywords: apoB
translational control
miRNA

Apolipoprotein B (apoB) is a key structural and functional protein of lipoproteins and is synthesized constitutively in the liver. This study investigated the role of microRNAs (miRNAs) in translational control of apolipoprotein B (apoB) mRNA and protein synthesis. Using bioinformatic analysis, I identified two specific miRNAs namely, miR-544 and miR-1202 with potential to interact with 3’ and 5’ UTR of apoB, respectively. Using HepG2 cells as the model system, the effects of transfection of exogenous miRNAs and inhibition of endogenous miRNAs were assessed on the expression of apoB mRNA and protein synthesis, as well as apoB mRNA traffic into cytoplasmic P-bodies. miR-544 induced a significant reduction in apoB mRNA expression and protein synthesis while increasing the co-localization of apoB mRNA into P-bodies. In contrast, transfection of miR-1202 increased apoB mRNA expression and protein synthesis. In summary, these data demonstrate that specific miRNAs are involved in translational control of apoB mRNA.