VictorJuiz/thesis huggingface dataset:
The Short-term and Long-term Effects of High-fat Diet on Adult Hippocampal Neurogenesis
Keywords: Adult neurogenesis
Dentate gyrus
Diet
High-fat diet
Hippocampus

Diet is an important factor in regulation of adult hippocampal neurogenesis (AHN). Diets that are high in saturated fatty acids have been shown to be associated with reduction in AHN specially in early developmental stages of the animal. Furthermore, these observed diet effects on AHN may be involved in mediating the cognitive impairments in animals on high-fat diets. The experiments presented in this thesis aimed to examine the short-term and long-term effects of a 4-week or 8-week period of high-fat diet (HFD; 45% of total energy contributed by saturated fatty acids) on AHN in young adult rats. Different stages of AHN were examined in this study including the proliferation, differentiation and maturation stages. Overall, contrary to what was expected, HFD did not cause a significant change in the level of AHN in any of the stages studied.
The Characterization of TiO2-coated Quartz Membranes and Their Application in NOM Degradation
Keywords: advances oxidation processes
membranes
NOM
photochemistry
TiO2 photocatalysis
water treatment

This research characterized novel TiO2-coated porous quartz disks (membranes) physically and chemically. Uncoated and TiO2-coated membranes were examined and compared using SEM images among other methods, which confirmed the presence of TiO2 deposits. The general adsorption characteristics and photoreactivity of these membranes was evaluated with methylene blue, MB, degradation experiments conducted in both batch configuration and in an enclosed reactor operated in down-flow and up-flow modes. Up-flow mode was found to be the most reliable reactor configuration, and 40 -- 70% MB removal was achieved in this mode using 0.2 -- 0.5 mg/L MB. The degradation of natural organic matter, NOM, has been evaluated using both lab-prepared and river waters under photolytic, dark and photocatalytic conditions. Unexpectedly, no significant decrease in DOC or UV-254 was observed in photocatalytic experiments compared to results from the adsorption or photolytic experiments, suggesting that adsorption was the prominent process of NOM removal under the conditions tested.
ERP-based Detection of Brain Pathology in Rat Models for Preclinical Alzheimer's Disease
Keywords: Alzheimer's disease
Asymptomatic preclinical stage
Cholinergic deficiency
Event-related potentials
hyperphosphorylated tau
support vector machine classifier

Early pathological features of Alzheimer's disease (AD) include the accumulation of hyperphosphorylated tau protein (HP-tau) in the entorhinal cortex and progressive loss of basal forebrain (BF) cholinergic neurons. These pathologies are known to remain asymptomatic for many years before AD is clinically diagnosed; however, they may induce aberrant brain processing which can be captured as an abnormality in event-related potentials (ERPs). Here, we examined cortical ERPs while a differential associative learning paradigm was applied to adult male rats with entorhinal HP-tau, pharmacological blockade of muscarinic acetylcholine receptors, or both conditions. Despite no impairment in differential associative and reversal learning, each pathological feature induced distinct abnormality in cortical ERPs to an extent that was sufficient for machine classifiers to accurately detect a specific type of pathology based on these ERP features. These results highlight a potential use of ERPs during differential associative learning as a biomarker for asymptomatic AD pathology.
Examining Audiovisual Integration in Amblyopia using the Sound-induced Flash Illusion
Keywords: amblyopia
audiovisual integration
multisensory integration
sound-induced flash illusion
temporal binding window
visual deprivation

Amblyopia is a neurodevelopmental disorder associated with reduced vision in one or both eyes, caused by abnormal visual experience during early childhood. The sound-induced flash illusion is a task in which flashes and sounds are presented concurrently, and the number of sounds influences the number of perceived flashes. This study examines the temporal binding window of audiovisual integration in amblyopia using the sound-induced flash illusion at different stimulus onset asynchronies of flashes and sounds. Eleven participants with amblyopia and sixteen visually normal controls were tested on the sound-induced flash illusion. Participants with amblyopia were equally susceptible to the illusion as controls, and showed a widening of the temporal binding window on the "fission" subset of the illusion (two sounds, one flash, percept of two flashes) when viewing binocularly and when the sounds precede the flash. This binocular-specific difference implies potential abnormal temporal integration in real-world situations.
Detailed Modelling of CO2 Addition Effects on the Evolution of Particle Size Distribution Functions in Premixed Ethylene Flames
Keywords: CO2 addition
Particle size distribution function
Premixed ethylene flame
Sectional approach
Sooting behaviour

This study investigates computationally the influence of CO2 addition on the sooting behaviour in premixed ethylene/ oxygen/ argon burner stabilized stagnation flames at the atmospheric pressure. The discrete sectional approach combined with a reversible nucleation model and a novel model of reversible polycyclic aromatic hydrocarbon (PAH) condensation were employed to solve the size evolution of the particle size distribution function (PSDF). The predicted temperature profiles and PSDFs are in reasonably good agreement with the experimental data for nascent soot measured in the burner stabilized stagnation configuration. The evolution of the PSDFs shows that CO2 addition reduces the soot nucleation and mass growth rates, consequently lowering the soot yield. The addition of CO2 reduces the concentrations of H, C2H2, and C6H6, which all suppress the soot formation process through a chemical effect, while its thermal effect is negligible.
Explorations into the Nucleophilicity of Aziridine and Utilization of Boron-containing Building Blocks in Organic Synthesis
Keywords: amphoteric molecules
aziridine
organoboron chemistry

Synthetic methods that achieve a high level of molecular complexity in a minimal number of steps using simple starting materials are highly valuable transformations in organic chemistry. Borylated ketenimines, representing a new class of [1,2]-amphoteric reagents, have been shown to be valuable intermediates in the rapid synthesis of alpha-borylazetidimines and 3-boryliminocoumarins. Herein, a successful expansion of the scope of these reactions has been demonstrated through trapping the borylated ketenimine intermediate in situ with various imines and salicylaldehyde derivatives. In addition, efforts toward synthesizing MIDA-boryl formate and MIDA-boryl formic acid (both [1,1]-amphoteric) via oxidation of hydroxymethyl MIDA boronate are reported. This led to the synthesis of a diboronate ester containing a BC(O)O structural motif. Also, for the purpose of better understanding the reactivity of aziridine aldehydes ([1,3]-amphoteric reagents), preliminary investigations into quantifying the nucleophilicity of aziridine suggest its nucleophilic character is weaker than that of other small, cyclic secondary amines.
The Impact of STEM Outreach Programs in Addressing Teacher Efficacy and Broader Issues in STEM Education
Keywords: outreach programs
professional development
STEM
teacher efficacy

This study explores the potential of the Outreach Workshops in STEM (OWS) to affect Science, Technology, Engineering, and Mathematics (STEM) teachers’ content knowledge, self-efficacy, and pedagogical approaches, as well as its viability as a potential form of professional development (PD). The data for the thesis is taken from a larger longitudinal study looking at the potential of OWS to influence middle school students’ and teachers’ attitudes and beliefs around STEM. The study employs a mixed-methods design, utilizing surveys, open-ended questions, interviews, and observations. The findings show that there were no significant changes in teachers’ content knowledge, confidence, or pedagogical approaches. However, the majority of participants reported that they learned new teaching ideas and considered the workshops to be an effective PD opportunity.
Residual Effects of Cannabis on Young Drivers' Performance of Driving-related Skills: An Interim Analysis
Keywords: Cannabis
Cognitive behaviours
Driving performance
Residual effects
Simulated driving
THC

The effects of cannabis may not be limited to the time period immediately after use. This current study examines the residual effects of cannabis on driving-related skills in young drivers using a high-fidelity driving simulator. The study is a randomized, double-blind, placebo-controlled mixed design trial. Eligible participants are regular cannabis-using drivers, aged 19-25, who smoke cannabis 1-4 days per week. Measures of simulated driving performance, cognitive and psychomotor functions, and subjective drug effects are collected concurrently with levels of cannabinoids in biological fluids before and after a one-time cannabis administration of active (12.5% THC) or placebo (
The Sparse Engram of the Lateral Amygdala
Keywords: Amygdala
Engram
Interneurons
Memory
Parvalbumin

Memories are stored by discrete changes in the brain, collectively referred to as an engram, that allow activity related to an experience to be reactivated in the future. Associative memories related to threatening stimuli are stored in the lateral amygdala (LA), where the engram is composed of a sparse proportion of neurons. The work in this thesis tests the prediction that this proportion is consistent between memories and investigates mechanisms that may contribute to this consistency. First, it is shown that the proportion of LA engram neurons remains constant between memories of different strengths. Then, it is shown that this proportion increases when inhibitory, parvalbumin-positive interneurons are suppressed during learning. Together, these results provide additional support for the idea memories are stored in sparse assemblies of neurons and suggest a novel role for parvalbumin-positive interneurons in memory formation.
Effectiveness of Standard vs Individualized Treatment on Smoking Cessation and Cue Reactivity: An fMRI Study
Keywords: Clinical Trial
fMRI
Neuroimaging
NRT
Smoking Cessation

Greater smoking cue reactivity has been associated with a higher likelihood of relapse; however, titrated dosing of the nicotine patch (tNRT) may have the potential to lower relapse rates. This study assessed the efficacy of titrated, standard dose tNRT and combination nicotine replacement therapy (NRT) as well as evaluated their impact on cue reactivity. Eighteen individuals began standard dose tNRT and those who failed to quit smoking after the second week of treatment were randomized to one of the other two treatments. The participants receiving standard dose tNRT were the only ones to display a change in reactivity in brain areas involved in cue-elicited craving and incentive salience. Despite its inability to modify cue reactivity, titrated therapy was associated with higher cessation rates (75%) than combination NRT (43%) and it was comparably safe. Therefore, titrated therapy may be a superior alternative for smokers who find standard dose tNRT ineffective.
Msh2-deficiency Affects the Differentiation and Proliferation of Small Intestinal Epithelial Cells
Keywords: Butyrate
Colorectal Cancer
Glucose
Mismatch repair
Msh2
Organoids

Mutations in mismatch repair genes, such as MSH2, are common lesions in Hereditary Nonpolyposis Colorectal Cancer and approximately 15% of all sporadic human colorectal cancers. Using organoids extracted from Msh2-/- murine intestines, we uncover structural differences in crypt development that can be attributed to Msh2-deficiency. Compared to Msh2+/- organoids, Msh2-/- organoids show a stunted ability to form new crypt protrusions during the first week of development. FACS analysis showed Msh2-/- freshly extracted intestinal epithelial cells and cultured organoids display a highly proliferative phenotype, marked by an increased percentage of EdU+ cells. Differentiation of intestinal epithelial cells is also affected by Msh2-deficiency as Msh2-/- epithelial cells and organoids display an increased CD24+ compartment, relative to Msh2+/-. The addition of butyrate to organoid culture media differentially affects proliferation across genotypes. Using the knowledge acquired in this study, we gain a further understanding of how Msh2-deficiency impacts intestinal structure and function.
Mental Health Outcomes in Survivors of Childhood Cancer
Keywords: mental health
pediatric cancer
survivorship

The current literature surrounding their mental health outcomes is limited. This study addresses limitations in the field by using healthcare administrative databases to compare the rates of mental health care utilization and the risk for a severe mental health episode between pediatric cancer survivors and matched population controls. Additionally, this study assesses the impact of demographic, disease, and treatment level predictors on mental health outcomes. Overall, pediatric cancer survivors were more likely to utilize mental health care (Adjusted Rate Ratio 1.31, 95% CI 1.16-1.48), but were not at greater risk of severe mental health episodes (Hazard Ratio 1.11 95% CI, 0.99-1.25). Pediatric cancer survivors were identified to be at increased risk of mood/affective disorders and psychotic disorders. In general, predictors of mental health outcomes in survivors were similar to those in the general population. This study provides novel information to a limited field, and a strong platform for future studies.
A Chemical Genetics Approach to Explore Anthocyanin Regulation in Nitrogen-deprived Arabidopsis Seedlings
Keywords: Anthocyanins
Arabidopsis thaliana
Chemical genetics
Nitrogen deprivation

Plants often experience varying soil nitrogen levels during their life cycle, and adjust growth and development to accommodate these changes. In the present study, a chemical genetics approach was implemented to discover molecular components involved in the induction of anthocyanin biosynthesis, in response to altered nitrogen levels. Using a robust high-throughput approach, a chemical library was screened to discover compounds capable of attenuating anthocyanin levels in nitrogen-deprived Arabidopsis seedlings. Chemical screens were successful in identifying four compounds that appear to mis-regulate anthocyanin accumulation during nitrogen deprivation. A chemical-induced phenotype was characterized, and the results indicate that chemical application must occur at a specific developmental stage. Furthermore, low nitrogen-induction of anthocyanins is highly sensitive to chemical application, and chemicals appear to exert their effect throughout early seedling growth. Future mutational and genome-wide studies will bridge the gap in understanding the link between anthocyanin biosynthesis and nitrogen availability.
Concordance between Need and Receipt of Social Support, Independence and Associations with Well-being in Women with Systemic Lupus Erythematosus
Keywords: lupus
SLE
support

Women living with Systemic Lupus Erythematosus (SLE) have the potential for increased support needs due to SLEâ s often severe and unpredictable symptoms. However, they may also strive to maintain their independence. A cross-sectional survey examined need for and evaluations of three types of social support in five diverse life domains and their associations with well-being and disease appraisals, demographic, clinical and social network characteristics. One hundred sixty-three (163) women, aged 19 â 88, were surveyed, drawing on an existing clinical cohort. Across domains, occurrences of concordance between the respondentsâ reported need for support and the support they received were associated with significantly greater well-being than occurrences of discordance. These findings held regardless of whether respondents were independent or dependent on others. This study highlights the need for interventions that emphasize optimizing social support - balancing independence and support needs - rather than assuming that maximizing support is always desirable.
The Final Flow: Istanbul's Fountains in Nineteenth-century European Narratives
Keywords: Istanbul
Ottoman History
Sanitation
Travelogues
Urban History
Water Systems

This thesis explores how developments in hydraulic technology and mentalities in Europe and the Ottoman Empire affected European depictions of Istanbul’s water system, particularly the fountain. This study advances our understanding of how the fountain came to be recognized by the late nineteenth century primarily for its artistic merit, and decontextualized from its role in the greater water network of the city. By comparing and analysing early nineteenth-century travelogues and news articles on fountains and water-systems to those from later on in the century, within the greater context of water history, we can uncover how these narratives were driven not only by “orientalizing” tendencies, but also a new, more hygienic focused “hydromentality.” This contextualization of European narratives lies less in asserting their reliability as testimony to the changes in Istanbul’s water system, but rather how their writings were a reflection of the changing attitudes and predilections of Europeans.
Melt-stretched Thermoplastic Honeycomb Sandwich Panels
Keywords: Honeycomb
Thermoplastic

Melt-stretched honeycombs were developed as a novel polymer honeycomb for structural applications. A fabrication process was devised in which a molten polymer is expanded between two flat platens, one of which is perforated with a pattern of holes. The resulting honeycomb structures show predictable internal architecture based on the locations of holes (air ingress sites) during manufacture. The process has been successfully applied to several grades of both polypropylene (PP) and polycarbonate (PC). Honeycombs have been created with hexagonal, square, triangular, and mixed cell geometries at cell sizes ranging from 5 - 40 mm. Despite the architectural differences as compared to their PC counterparts, low melt flow rate PP was found to produce the strongest structures in out-of-plane compression. Some honeycombs manufactured in this study demonstrate significantly better out-of-plane specific compressive strength than commercially-available thermoplastic honeycombs or structural foams, while maintaining a higher degree of recyclability.
Time-dependent Trajectory of Behavioural Emotionality in the Unpredictable Chronic Mild Stress Rodent Model of Depression
Keywords: Animal Models
Chronic Stress
Depression
Magnetic Resonance Imaging
Strain Differences
Synaptic Proteins

Major depressive disorder (MDD) is a severe mental illness. Translational animal models of the human pathophysiology are limited. Sex and genetic differences contribute to the risk for developing MDD. Further, magnetic resonance imaging (MRI) studies describe volumetric changes in limbic regions in MDD patients and preclinical studies have attributed these to synaptic changes. However, a link between these features has yet to be determined. To help bridge this gap, behavioural, volumetric and synaptic changes were investigated in mice exposed to unpredictable chronic mild stress. Using a novel paradigm, behavioural emotionality was detected repeatedly across sex and strain (Balb/c and C57Bl/6) and was comparable to classical tests. Behavioural emotionality in male Balb/c mice negatively correlated with MRI amygdalar volumes and was associated with an increase in the postsynaptic density protein 95 (PSD95) marker. Altogether these results provided a translational perspective on the biological mechanisms involved in MDD.
Who Needs Hybridity? The Political Limits of Mixed Race Identity
Keywords: Anticolonial
Asian Studies
Canadian Studies
Critical Race
Feminism
Mixed-race

This thesis examines how non-white, mixed race women with Asian heritage understand, participate in, and resist colonialism, anti-blackness and anti-Indigeneity. The study finds that mixed race identification is contextual and shifts according to the racial make-up of spaces. Participants performed their identities in white spaces differently than in communities of colour. Although all participants could name whiteness, their awareness of the racial and colonial basis of citizenship was situated on a spectrum. The thesis explores how race is understood through multiple axes of identity such as disability, gender, and sexuality. Although the family is often a good space to learn about race, multiracial families sometimes reproduced ableism, queer-phobia, anti-blackness and shadism. Lastly, I focus on how hybridity is a sexualized discourse that contributes to the fetishization of multiraciality. I highlight the sexualized forms of violence that multiracial women encounter.
Human Neutrophil Peptide: Diagnostic and Prognostic Properties in Critically Ill Patients
Keywords: Critical Care Patients
Human Neutrophil Peptide
Neutrophils
Sepsis
Systemic Inflammatory Response

Background: Neutrophil activation is a hallmark of the inflammatory process and human neutrophil peptides (HNPs) are the most abundant proteins released from neutrophils. We hypothesized that HNP concentrations are associated with: (a) the presence of infection, (b) high blood neutrophil activity, (c) organ dysfunction and (d) mortality in critically ill patients. Methods: Plasma samples, demographic, resuscitative and biochemical data were obtained from 100 patients admitted to the intensive care unit with acute physiology and chronic health evaluation II scores of 22â 29. Nine healthy volunteers served as controls. Results: Plasma HNP concentrations were higher in critically ill patients than in healthy controls. Organ dysfunction was more common in noninfected than in infected patients, specifically among cardiothoracic patients. Higher plasma HNP concentrations were associated with higher mortality. Summary: The inflammatory process contributes to higher plasma HNP concentrations, which correlate with organ dysfunction and mortality in critically ill patients.
Impacts of Contracted Endodontic Cavities on Instrumentation Efficacy and Biomechanical Responses in Maxillary Molars
Keywords: endodontic cavity
fracture strength
instrumentation efficacy
minimally invasive
root strain

This study assessed impacts of contracted (CEC) and traditional (TEC) cavities on instrumentation efficacy and biomechanical responses in maxillary molars. Eighteen extracted intact maxillary molars were imaged with micro-CT and accessed through CEC or TEC (n=9/group). Canals were instrumented, re-imaged and proportion of modified canal wall (MCW) determined. Another 28 molars (n=14/group) with strain gauges were subjected to load cycles and microstrain recorded before access and after cavity restoration. These 28 molars and additional 11 intact molars were fatigued and loaded to failure. Data were analyzed with Wilcoxon rank sum and Kruskal-Wallis tests. Mean proportion MCW did not differ significantly between CEC (49.7±12.0%) and TEC (44.7±9.0%). Changes in microstrain displayed no specific pattern in both groups. Mean load-at-failure for CEC (1703±558N) did not differ significantly from TEC (1384±377N); both were lower (p