VictorJuiz/thesis huggingface dataset:
Cation Impact on N-Nitrosodimethylamine (NDMA) Formation from Ranitidine in Different Water Matrices
Keywords: Cations
NDMA
Ranitidine

In previous research, ranitidine has formed high yields of the disinfection by-product N-Nitrosodimethylamine (NDMA) upon chloramination. In the current research, bench-scale experiments were conducted to investigate the impact of cations (i.e., Ca2+, Mg2+, and Na+) on NDMA formation from ranitidine in three water matrices (Milli-Q® water, Lake Ontario water, and Otonabee River water) under practical chloramine disinfection conditions. In Milli-Q® water, excess cations did not change the yields of NDMA. NDMA formation kinetic profiles monitored in the lake and river water also indicated that elevating the cation concentrations did not affect the ultimate NDMA formation from ranitidine, but then did affect the observed rates of NDMA formation; the rates underwent an initial decrease and a subsequent increase as the cation concentrations were increased. The lowest reaction rates were observed in the lake and river water samples when they have a hardness level of 240 and 203 mg/L as CaCO3, respectively.
Ultrafiltration Fouling: Impact of Backwash Frequency and Air Sparging
Keywords: ultrafiltration
fouling
air sparging
backwash

A bench-scale study was performed to optimize backwash frequency and air sparging conditions during ultrafiltration (UF) of natural surface waters in order to maximize water production and minimize irreversible fouling as well as operating and maintenance costs. Surface shear stress representing different air sparging conditions (continuous coarse bubble, discontinuous coarse bubble, and large pulse bubble sparging) was applied in combination with various backwash frequencies (0.5, 2 and 6 h) and fouling was assessed. Results indicated that air sparging with discontinuous coarse bubbles or large pulse bubbles significantly reduced the irreversible fouling rate while providing cost savings when compared to the baseline condition, which assumed a 0.5 h-backwash frequency and no air sparging during filtration. Cost savings were more pronounced at lower backwash frequencies, due to value associated with extra water produced over longer filtration times and longer membrane life resulted from fewer recovery chemical cleans because of lower irreversible fouling.
Study of Flexible Multi-wall Carbon Nano-tubes / Conductivepolymer Composites for Supercapacitor Applications
Keywords: Supercapacitors
Conductive polymer
Carbon nanotubes
composites
Polypyrrole
Polyaniline
PEDOT

Conductive polymers are promising pseudo capacitive materials as they feature both good conductivity and high capacitance. Formation of composite between conductive polymers and carbon nanotubes is a proven technique in enhancing the material electroactivity. In-situ polymerization of conductive polymers includes polyaniline, polypyrrole and PEDOT: PSS and composite with MWCNT has been successfully achieved. Composites fabricated by using different dopants and their performance were studied. Excellent achieved capacitive performance is due to the combination of pseudo capacitance and double layer capacitance. The MWCNTs content has significant influence on the morphology and structure of the polymerized ECP in the composite. And therefore affects the material conductivity and the charge storage performance. Two electrodes cell performance shows that Ppy/MWCNT composite shows a more promising performance as electrode materials for EC applications in contrast to PANI/MWCNT and PEDOT: PSS/MWCNT composites.
Local to Mobile Devices for Nuclear Operations
Keywords: mobile devices
TAM

The AECL National Research Universal (NRU) reactor has implemented a new mobile device to help Operators collect instrument data. Instruments display readings through various analog and digital devices. Before the change, Operators collected readings via a paper and pen method. With the implementation of the mobile device, Operators scan a barcode and input the instrument’s reading using a mobile device. To understand the factors that influence Operator acceptance of the new technology, the Technology Acceptance Model (TAM) was used to identify determinants that have the biggest impact on the Operators’ intention to use the mobile device. The TAM results identified the determinants that were most influential and the mobile interface was redesigned, based on the TAM results. Once the interfaces were redesigned they were evaluated through a usability study that compared the original interface with the newly designed screens. The results did not show statistically significant differences between the screens.
Design of a Bioreactor to Mimic Hemodynamic Shear Stresses on Endothelial Cells in Microfluidic Systems
Keywords: Endothelial cell
Bioreactor
Flow loop
Cardiovascular disease
CVD
Waveform
Microfluidics
Microfluidic devices
Hemodynamics
EC
Shear stress
Shear
Pump
Actuator
Mechanical engineering
Biomedical engineering
PIV
Particle image velocimetry
Fluid dynamics
Fluid mechanics
Pressure
Model
Syringe
Peristaltic
Blood
Blood flow
Wall shear stress
Womersley number
Womersley
Purday
Physiological
Flowmeter
Sinusoid
Sinusoidal
Disturbed
Non-disturbed
Undisturbed
Oscillatory
Pulsatile
In vivo
In vitro

The mechanisms behind cardiovascular disease (CVD) initiation and progression are not fully elucidated. It is hypothesized that blood flow patterns regulate endothelial cell (EC) function to affect the progression of CVDs. A system that subjects ECs to physiologically-relevant shear stress waveforms within microfluidic devices has not yet been demonstrated, despite the advantages associated with the use of these devices. In this work, a bioreactor was designed to fulfill this need. Waveforms from regions commonly affected by CVDs including were derived. Pump motion and fluid flow profiles were validated by actuator motion tracking, particle image velocimetry, and flowmeters. While several relevant waveforms were successfully replicated, physiological waveforms could not be produced at physiological frequencies owing to actuator velocity and accuracy limitations, as well as dampening effects in the system. Overall, this work lays the foundation for designing a system that provides insight into the role of shear stress in CVD pathogenesis.
The Health Consequences of Fructose, its Metabolite, Dihydroxyacetone and the Hepatoprotective Effects of Selected Natural Polyphenols in Rat Hhepatocytes
Keywords: Glyoxal
Methylglyoxal
Oxidative stress
Autoxidation
Protein carbonylation
Polyphenols

The introduction of high fructose corn syrup into the diet has been proposed to be the cause of many illnesses related to the metabolic syndrome. Fructose and its metabolites can be metabolized into cytotoxic reactive dicarbonyls that can cause damage to macromolecules leading to deleterious consequences. Dihydroxyacetone, a fructose metabolite, was studied in this thesis. Its ability to autoxidize and cause protein carbonylation under standard (pH 7.4, 37°C) and oxidative stress conditions (Fentons reagent) was investigated. Dihydroxyacetone was able to form significant amounts of dicarbonyls and protein carbonylation. Several selected natural polyphenols were chosen for an in vitro toxicological study involving rat hepatocytes. The chosen dietary polyphenols were rutin, gallic acid, methylgallate, ethylgallate, propylgallate and curcumin. In this thesis, the polyphenols were found to be able to significantly protect against the deleterious effects of glyoxal and methylglyoxal. In summary, these polyphenols could be candidates for future in vivo studies.
Anti-GPIbα Mediated Platelet Desialylation and Activation: A Novel Fc-independent Platelet Clearance Mechanism and Potential Therapeutic and Diagnostic Target in ITP
Keywords: Immune thrombocytopeni
Fc-independent clearance

Immune thrombocytopenia (ITP) is a common bleeding disorder caused primarily by autoantibodies against platelet GPIIbIIIa and/or the GPIb complex. Current theory suggests antibody-mediated platelet destruction occurs in the spleen via Fcγ receptors (FcγR). However, it has been demonstrated that anti-GPIbα-mediated ITP is often refractory to therapies targeting FcγR pathways. Utilizing a panel of murine monoclonal antibodies (mAbs) against murine and human GPIIbIIIa and GPIbα, it was found that anti-GPIbα induces not only platelet activation to a much greater extent than anti-GPIIbIIIa antibodies, but also significant surface expression of neuraminidase 1 and platelet desialylation. Utilizing inhibitors of platelet activation and desialylation, it was found that these two processes are not mutually exclusive, but rather exist in a positive feedback loop, leading to FcγR-independent platelet clearance in the liver likely via Ashwell-Morell receptors. Furthermore, in a murine model of ITP, sialidase inhibitor treatment rescued platelet counts in predominantly anti-GPIbα -mediated thrombocytopenia.
Preliminary Design of Slender Reinforced Concrete Highway Bridge Pier Systems
Keywords: columns
slender piers
pier systems
bridges
structures
second-order effects
concrete
reinforcement ratio
slenderness ratio
material nonlinearity
geometric nonlinearity

Feasible span-to-depth ratios for many modern bridge systems have been identified and documented in literature. No such parameters have been adequately identified in terms of proportioning bridge piers. This thesis includes a study of 22 existing reinforced concrete highway bridges and their respective pier systems to determine the state-of-the-art in design. The effect of different geometric and material parameters such as concrete strength, reinforcement ratio and slenderness ratio on the structural behavior of individual piers and multiple pier systems was examined. Approximate methods, which may be used for the purposes of preliminary design are discussed and reviewed. Serviceability and ultimate limit states design aids that can be used to identify appropriate preliminary cross-sectional pier dimensions and reinforcement ratios for individual piers given various slenderness ratios were developed. The structural behavior as well as an approach to the preliminary design of multiple pier bridge systems is presented.
Involvement of the C-terminal Repeat (CTR) Domain in the Protein Interactions and Functions of Spt5
Keywords: Transcription, Histone Modification, Gene Splicing, Nucleosome, mRNA Processing, Phosphorylation, Epigenetics

Transcription elongation by RNA polymerase II is regulated by an array of protein complexes. Among various elongation factors, Spt5 is conserved in the three kingdoms of life. I investigated functional interactions of its C-terminal repeats (CTR) domain with several elongation protein complexes in Saccharomyces cerevisiae. By using genetics and molecular biology methods, I established two major pathways in this thesis. The first describes how BUR kinase-mediated phosphorylation of CTR domain leads to co-transcriptional recruitment of the PAF complex to regulate histone modifications on active genes. The second describes how CTR phosphorylation facilitates recruitment of capping enzymes to enhance gene splicing. Finally, several Spt5-associated protein complexes were studied, and potential molecular mechanisms underlying these observations are proposed and discussed.
A Novel Design for Fully Printed Flexible AC-driven Powder Electroluminescent Devices on Paper
Keywords: electroluminescent device
printed electronics
pulp and paper

ACPEL devices were fabricated onto various paper substrates. The dielectric and phosphor layers were mask printed, a PEDOT:PSS/SWCNT ink was inkjet-printed for the cathode and a translucent conductor was applied with a paintbrush for the anode resulting in a maximum luminance of 8.05 cd/m2 at 300 VAC and 60 Hz. It was found that the conductivity of the PEDOT:PSS/SWCNT ink on the various paper types was affected by the coating and paper thickness. Novel ACPEL devices were also fabricated by incorporating paper as the dielectric layer of the device. The maximum luminance achieved was 7.24 cd/m2 at 300 VAC and 60 Hz. It is shown that the dielectric constant of the paper and hence the performance of the resulting EL device may be enhanced by filling the sheet with BaTiO3 and by the surface treatment of the sheet.
Tension Stiffening and Cracking Behaviour of GFRP Reinforced Concrete
Keywords: tension stiffening
crack spacing
GFRP
concrete

Glass Fibre-Reinforced Polymer (GFRP) bars offer a feasible alternative in locations where steel is not the suitable reinforcement; namely locations that are sensitive to corrosion. In this study 60 specimens, 52 GFRP reinforced and 8 steel reinforced, were constructed and tested under direct tension in order to investigate the tension stiffening and cracking behaviour. The effects of different variables such as the bar type, the bar diameter, the reinforcement ratio and the concrete strength on tension stiffening and crack spacing were studied. The current code provisions for tension stiffening, namely ACI-440 and CEB-FIP were evaluated against the obtained test data. It was determined that the current code provisions significantly overestimate tension stiffening in GFRP reinforced specimens. A new tension stiffening model was, therefore, developed that provides better simulation of the test data. The CEB-FIP 1978 model for crack spacing was also modified for GFRP reinforced members.
Evaluation and Verification of Aerosol Diluters: Accuracy and Particle Loss
Keywords: Aerosol Diluter
Particle Loss

The aerosol diluter characteristics of three different systems, the single-stage and the two-stage TSI 379020A rotary disk thermodiluters and Dekati FPS-4000 ejector diluter, were tested using gases and particles over a range of dilution ratios. The upstream and downstream gas and particle concentrations of the diluters were measured in real-time to compute the actual dilution ratio achieved by the three systems. Dilution ratios from approximately 15 to 100 were found to fall within the expected operating error margin of ± 10% for CO2 and CH4. Dilution ratios covering a similar range were also achieved to within ± 10% for particles with diameters from 9.3 to 200 nm. However, when engine exhaust was sampled, significant loss of particles smaller than 29.4 nm occurred during the dilution process. As the dilution ratio increased, the deviation from the expected value increased due to an increase in measurement uncertainty.
Epigenetic Studies of Bipolar Disorder
Keywords: bipolar disorder
epigenetics
suicidal behaviour
genetics
psychiatric disorder
mood disorder

Bipolar disorder is a psychiatric illness characterized by recurrent fluctuations in mood and increased risk of suicide. Twin and family studies have identified the highly heritable nature of the disorder, but the limitations of the current DNA-centric paradigm underscore the need for a new perspective to gain a clearer understanding of its basis. This project investigates various facets of bipolar disorder from an epigenetic standpoint. We used mass spectrometry-based mapping of individual DNA modification differences of the brain-derived neurotrophic factor gene. Moreover, the epigenetic basis of suicidal behaviour in bipolar disorder was investigated using DNA methylation microarrays. We also used a newly-developed enrichment technique, mTAG, to interrogate chromosome-wide DNA modification profiles using tiling microarrays in post-mortem brains of bipolar disease patients and controls. Findings from these experiments highlight observable features of epigenomes of patients affected with mood disorders, and may further the understanding of the molecular origin of psychiatric diseases.
MicroRNA Profiling in Experimental Sepsis-induced Acute Lung Injury
Keywords: microRNA
acute lung injury
experimental sepsis
mesenchymal stem cells
treatment
transcriptome

Introduction: Currently, there are no specific pharmacological treatments for sepsis-induced acute respiratory distress syndrome (ARDS). And mesenchymal stem cells (MSCs) have shown reparative potential in both sepsis and ARDS. Objectives: To determine the role of MSC administration in the modulation of pulmonary host-responses to sepsis via differential regulation of regulatory microRNAs (miRNAs/miRs). Methods: MicroRNA and mRNA profiling was performed to identify differential expression. Quantitative real time polymerase chain reaction (qRT-PCR), trans-endothelial electrical resistance (TEER) measurements, and luciferase activity assay were used. Results: MicroRNA expression was examined in Human Pulmonary Microvascular Endothelial Cells (HPMECs). One miRNA – miR-193b-5p, targets occludin, a tight junction protein associated with endothelial leakage. A specific regulatory relationship between miR-193b-5p and occludin was identified. The loss in endothelial integrity was rescued when miR-193b-5p inhibitor was transfected. Conclusion: miR-193b-5p is a suppressor of occludin. Studying transcriptional changes allows identification of therapeutically relevant mediators for ARDS/ALI treatment.
Generic Drug Pricing and Substitution in Private Drug Plans in Canada
Keywords: Private insurance
Generic drug
Drug reimbursement
Drug substitution
Drug costs

Purpose: To estimate the willingness and ability of private plans to manage costs during the generic drug procurement reform era that began in 2006 in Canada. Two cost management aspects were assessed; the prices paid for generic drugs and the extent to which private plans have enacted measures to increase generic substitution. Methods: IMS-Brogan Pharmastat data was used to estimate the price of commonly prescribed generic drugs and generic share of prescriptions, by plan type, province and quarter from 2003 to 2012. Results: Prices did not decline unless the provincial governments mandated the reductions. Savings from this mandate was approximately $264 million in Ontario. Rates of generic substitution were unaffected by the price reductions, possibly because the rates were high beforehand. Conclusion: Private plans did not independently obtain lower generic prices. Due to already high substitution rates, there may have been limited potential for additional savings from mandatory substitution controls.
Usability of Paper-based Industrial Operating Procedures
Keywords: procedure
usability
checklist
design guidelines

Procedures are standardized lists of instructions that designate the safe and accepted way of accomplishing a task. This study intended to develop and compare the usability of paper-based industrial operating procedures. Two procedures at a plant were redesigned with evidence-based guidelines and human factors input. 16 operators of varying experience were asked to read through and assess the new and old procedures. The new procedures were rated significantly or moderately better than their predecessors for efficiency, effectiveness, and subjective satisfaction. On average, inexperienced operators reported fewer inaccuracies, more confusion, and higher workload ratings than their experienced counterparts, regardless of procedure type or area. For satisfaction, experienced and inexperienced operators reported similar ratings across both procedure types and areas. Future studies should attempt to discern which particular change in the procedures contributed the most to increased usability, and whether operator experience significantly correlates with usability ratings.
Association Between Electroretinogram-identified Vigabatrin Toxicity and Subsequent Visual Field Reduction
Keywords: vigabatrin
visual fields

Vigabatrin (VGB) is an antiepileptic drug approved for pediatric patients with infantile spasms. VGB is associated with visual field reductions in 30-50% of adults taking the drug. The amplitude of the 30-Hz flicker electroretinogram (ERG) is recommended for screening young children on VGB treatment. To determine if standard ERG tests for VGB toxicity are correlated with visual field reductions, 22 individuals who were previously on VGB underwent visual assessment. This study also validated the use of high-resolution OCT for detecting structural changes associated with VGB toxicity. This study demonstrates that the ERG was associated with visual field loss, as measured along the temporal meridian. The retinal nerve fibre layer (RNFL) was attenuated in all children who showed a reduction in the visual fields indicating that RNFL attenuation may be a sensitive marker for VGB toxicity. We recommend using serial OCTs to monitor VGB toxicity since it is fast and non-invasive.
Settlement, Food Lands, and Sustainable Habitation: The Historical Development of Agricultural Policy and Urban Planning in Southern Ontario
Keywords: Southern Ontario
Landscape
Land-use
Food
Farming
Settlement

In this thesis I recount the historical relationship between settlement and food lands in Southern Ontario. Informed by landscape and food regime theory, I use a landscape approach to interpret the history of this relationship to deepen our understanding of a pertinent, and historically specific problem of land access for sustainable farming. This thesis presents entrenched barriers to landscape renewal as institutional legacies of various layers of history. It argues that at the moment and for the last century Southern Ontario has had two different, parallel sets of determinants for land-use operating on the same landscape in the form of agricultural policy and urban planning. To the extent that they are not purposefully coordinated, not just with each other but with the social and ecological foundations of our habitation, this is at the root of the problem of land access for sustainable farming.
Retinal Blood Flow in Patients with Primary Open Angle Glaucoma and Optic Disc Hemorrhage
Keywords: Retinal Blood Flow
Glaucoma
Disc Hemorrhage

Purpose: To investigate venous total retinal blood flow (TRBF) and retinal blood flow (RBF) in the superior and the inferior retinal hemifields in primary open angle glaucoma (POAG) patients with, and without, disc hemorrhage (DH). Methods: RBF measurements were obtained from 10 POAG with DH and 19 POAG without DH using Doppler SD-OCT (RTVue) as well as bi-directional laser Doppler flowmetry (CLBF). Results: RBF was not different between the superior and inferior hemifields for either of the two groups. Venous TRBF in the POAG with DH group was significantly lower than in the age-matched stable POAG without DH group (p=0.009). In the POAG with DH group, venous TRBF was significantly lower in the DH eye compared to contralateral eye without DH (p=0.015). Conclusions: Venous TRBF was significantly lower in the POAG with DH group compared to both the POAG without DH group and the contralateral eye of the POAG with DH group.
Fully Quadratic Vibronic Model of Electronic Transitions through Conical Intersections
Keywords: conical intersections
dynamics

We introduce a perturbative method for studying photoinduced electronic transitions through conical intersections. Our approach uses a quadratic vibronic coupling Hamiltonian and second order cumulant approximation for the diabatic coupling to derive an analytical expression for time evolution of electronic populations at given temperatures. The formalism is an extension of a previous method called the non-equilibrium Fermi golden rule approach which used the linear vibronic coupling Hamiltonian with the same cumulant treatment for diabatic coupling. The advantage of the quadratic Hamiltonian is that it can include electronic states with different frequencies and normal modes. We explore these advantages with 2D models showing the improved accuracy of the new quadratic method over the linear method. We then apply our formalism to some real molecules, 2,6-bis(methylene) adamantyl cation, and its dimethyl derivative, with parameters obtained from electronic structure calculations followed by diabatization. The results show good agreement with quantum dynamics techniques.