VictorJuiz/thesis huggingface dataset:
Investigating the Role of microRNAs in Human Congenital Hepatic Fibrosis
Keywords: ARPKD
Cholangiocytes
Congenital Hepatic Fibrosis
Differential Expression
microRNA
RNA Sequencing

Congenital Hepatic Fibrosis (CHF) is histologically characterized by increased profile of dilated biliary tracts and progressive periportal fibrosis. We describe for the first time the change in microRNA expression pattern in human CHF liver tissues using miRNA-sequencing analysis. The expression pattern of miRNAs in the CHF patient liver is distinguishable from that of normal and other typical forms of hepatic fibrosis by differential analysis. We have isolated, for the first time, diseased biliary epithelial cells from patients with human Congenital Hepatic Fibrosis using Laser Capture Micro-dissection. We verified that the dysregulated miRNA in CHF whole liver were also dysregulated in diseased cholangiocytes. In silico target prediction of candidate miRNAs shows that molecular pathways that are associated with CHF were under the regulation of dysregulated miRNA targets. These results may provide insight into a regulatory network of miRNAs with crucial functional roles in the disease pathology of CHF.
The Effect of Simulated Human Salivary Enzymes and Matrix Metalloproteinase (MMP) Inhibition on the Degradation and Fracture Toughness of the Self-etched Resin-dentin Interface
Keywords: Biodegradaion
Esterase
Fracture Toughness
Matrix metalloproteinase (MMPs)
Resin-dentin interface
Self-etch adhesive

Background: Oral esterase activities and dentinal matrix metalloproteinases (MMPs) contribute to interfacial degradation of composite restorations, compromising structural integrity, and increasing risk of secondary caries. Hypothesis: MMP inhibition modulates simulated human salivary esterase (SHSE) accelerated degradation of mechanical performance parameters for composite-dentin bonds achieved via self-etched adhesives. Objective: Assess the effect of SHSE and MMP inhibition on biostability, interfacial fracture toughness (FT), and failure mode (FM) for self-etched resin-dentin interfaces. Materials and Methods: FT and FM analyses were performed on mini short-rod FT specimens (N=10/group), prepared with Easy Bond, with and without MMP inhibition (galardin), after incubation for 0, 7, 30, 90, or 180 days in phosphate buffered saline (PBS) or SHSE. Results and Conclusions: FM shifts into the composite/adhesive vs. hybrid-layer after longer incubation periods. Despite higher amounts of the degradation marker, Bis-hydroxy-propoxy-phenyl-propane, collected from SHSE vs. PBS (p
Haptoglobin 2-2 is Associated with Presence and Progression of MRI Depicted Carotid Intraplaque Hemorrhage
Keywords: Atherosclerosis
Biomarker
Haptoglobin
Intraplaque Hemorrhage
MRI

Intraplaque hemorrhage (IPH) is a source of free hemoglobin that binds the haptoglobin protein and forms a complex cleared by tissue macrophages. There are three haptoglobin genotypes: Hp1-1, Hp2-2 and Hp1-2. The Hb-Hp2-2 complex has a lower affinity for macrophages, resulting in vascular oxidative burden. We hypothesized that Hp2-2 patientsâ failure to clear hemoglobin results in a greater prevalence and progression of IPH. Eighty patients with advanced vascular disease (>30% carotid stenosis) underwent carotid MRI. IPH was quantified using the VesselMass software. Haptoglobin was genotyped and phenotyped using established protocols. Logistic and longitudinal regression analyses were performed. Hp2-2 patients had a significantly higher prevalence of baseline IPH (p=0.02). Longitudinal analysis of 35 IPH positive carotids indicated a significant progression of IPH volume over time in Hp2-2 patients (p=0.003). Therefore, Hp2-2 patients had a significantly higher prevalence and progression of carotid IPH. Hp2-2 genotype may be a biomarker of IPH and can identify at-risk populations for more targeted imaging investigations.
Elucidating the Roles of TCAP-1 on Glucose Transport and Muscle Physiology
Keywords: Endocrinology
Glucose
Metabolism
Muscle
Peptide
Physiology

Teneurin C-terminal associated peptide (TCAP)-1 is a cleavable bioactive peptide on the carboxy terminus of teneurin proteins. Previous findings indicate that the primary role of TCAP-1 may be to regulate metabolic optimization in the brain by increasing the efficiency of glucose transport and energy utilization. The findings show that TCAP-1 administration in rats results in a 20-30% decrease in plasma glucose levels and an increase in 18F-2-deoxyglucose uptake into the cortex. In vitro, TCAP-1 also induces 3H-deoxyglucose transport into hypothalamic neurons via an insulin-independent manner. This is correlated with an increase in membrane GLUT3 immunoreactivity. A previously deduced pathway by which TCAP-1 signals in vitro was used to establish a link between the MEK-ERK1/2 pathway and glucose uptake as well as a connection between the MEK-ERK1/2 and AMPK pathways. Immunoreactivity studies indicate that the TCAP-1 system exists in muscle and may play a part in skeletal muscle metabolism and physiology.
Synthesis, Size-selective Separation and Characterization of Colloidally Stable, Water-soluble Silicon Nanocrystals
Keywords: Quantum dots
Silicon Nanocrystals
Size-selective separation

In the field of silicon nanocrystals (ncSi), polydispersity, pH-independent aqueous colloidal stability, near-infrared (NIR) to visible photoluminescence tunability and cytotoxicity present significant challenges in the elucidation of important size-dependent physical, chemical, and biological properties. This thesis outlines some contributions towards understanding and addressing these challenges with special consideration towards biological fluorescent cell labelling. We begin by demonstrating the synthesis of polydisperse ncSi functionalized with 10-undecenoic acid (ncSi:UDA) which are size-separated using two different size-separation methods: size-selective precipitation and sucrose density gradient ultracentrifugation. Further improvements are then made on the pH-independent colloidal stability of ncSi:UDA by coupling the carboxylic acid terminus to poly(ethylene glycol) (ncSi:UDAPEG). Finally, the colloidal stability of NIR-emitting ncSi:UDA is investigated through the synthesis and hydrolysis of ethyl 10-undecenoate-functionalized ncSi (ncSi:EUD).
Evaluation and Optimization of Cellulose and PVDF Membranes for Application in Membrane Bioreactors and Vacuum Membrane Distillation for Water and Wastewater Treatment
Keywords: Cellulose
Membrane Bioreactor
Membrane Distillation
Wastewater
Water

As water sources around the world are depleted, there is an increasing need for advanced treatment systems that can produce high-quality effluent for discharge or reuse. In this thesis, cellulose membranes were used in a bench-scale membrane bioreactor with the intention of developing a membrane that is inexpensive and made from renewable resources. The cellulose membranes were able to remove suspended solids during multi-day filtrations, but suffered from severe fouling. The membranes developed in this study are unique, as they are manufactured using a papermaking process instead of conventional casting processes. Next, a bench-scale vacuum membrane distillation system was tested using salt solutions, surface water, and MBR effluent as feed solutions. With all feed solutions, this system could produce a permeate with low conductivity and dissolved solids, and free of coliforms. Combining these two systems provides an option for water reuse which has not been previously studied.
Investigating the Role of NRG1β/ErbB4 Signalling in LTP
Keywords: LTP
NMDAR
NRG1
Synapse

Synaptic plasticity is the fundamental feature of the mammalian brain that enables learning and memory. One main form of activity-dependent, lasting increase in synaptic transmission termed LTP is observed at the hippocampal CA1 and mediated by the NMDARs. Schizophrenia susceptibility pathway NRG1β/ErbB4 has been implicated in physiological, as well as aberrant, regulation of NMDAR function. Prevention of LTP induction is the consensus phenomenology observed in studies involving exogenous application of NRG1β on acute hippocampal slice preparations. Recent efforts demonstrated that NRG1β-mediated suppression of LTP involves the inhibition of nonreceptor tyrosine kinase Src; however; the exact mechanism remains controversial. After observing no effect of NRG1β application on LTP, I carried out a step-wise interrogation NRG1β/ErbB4 ligand-receptor pair. In this thesis, I present evidence for an experimental-condition-dependent downregulation of ErbB4 expression; this finding bears important implications for experimental design, in addition to broadening our understanding of the mechanisms governing NRG1β/ErbB4 signalling.
Characterization of Adult Progenitor Cells and their Fate in a Rat Femur Fracture Model
Keywords: Fracture Healing
Stem Cell Therapy

This study was carried out to characterize two progenitor cell populations in the context of orthopaedics and to examining their fate in a rat bone defect model. Endothelial progenitor cells (EPCs) and mesenchymal stem cells (MSCs) isolated from syngeneic bone marrow were characterized utilizing flow cytometry and osteogenic/angiogenic differentiation assays in vitro. To assess in vivo fate, genetically labeled cells were implanted into a defect and examined at two and four weeks post-implantation. Fluorescent microangiography (FMA) was used to model nascent vasculature two weeks post-implantation. The results show populations that resemble established definitions. In vitro, EPCs demonstrated a similar osteogenic capacity to MSCs and superior angiogenic capacity on the basis of tube formation. In vivo experiments showed presence of cells at the fracture site at 2 and 4 weeks. EPCs showed a trend towards increased vessel formation with FMA. These results provide groundwork for future investigation into mechanisms of healing.
The Influence of Postsynaptic Structures on Missing Quanta at the Drosophila Neuromuscular Junction
Keywords: Drosophila
Electrophysiology
Neuromuscular Junction
Neurophysiology
Synaptic Transmission

Synaptic transmission requires both pre- and post-synaptic elements for neural communication. The postsynaptic structure contributes to the effectiveness of synaptic currents to induce voltage changes in postsynaptic cells. At the Drosophila neuromuscular junction (NMJ), the poorly understood subsynaptic reticulum (SSR) consists of elaborate membrane folds that link the synaptic contacts to the muscle. I investigate the function of the SSR by conducting electrophysiological experiments on genetic mutants that regulate SSR complexity. I observed that some synaptic currents do not result in postsynaptic voltage changes, events called ‘missing quanta’. Furthermore, the frequency of missing quanta is positively correlated with SSR complexity. Based on cable theory, I propose that the SSR contributes to missing quanta by acting as a filter or a switch for some synaptic events. Further understanding on the role of the SSR in synaptic transmission and ‘missing quanta’ will yield important information about synaptic transmission at the Drosophila NMJ.
Examining the Multicultural Experiences of Chinese Graduate Students at the University of Toronto through the Lens of Critical Multiculturalism
Keywords: critical multiculturalism
international students
multicultural education
multicultural experiences

This research project investigates Chinese international students multicultural experiences. The existing literature shows that language barrier, cultural adjustment and social support are the major factors that influence international studentsâ life abroad. However, with liberal multiculturalism as the mainstream ideology, multicultural research appears to have a liberal multiculturalism tendency. In this research project, critical multiculturalism is employed as the theoretical framework to avoid the negative impacts from liberal multiculturalism. The study is based on the narratives of four Chinese international students at the University of Toronto. The results of the study show that the lack of recognition of cultural diversity, the evaluation of cultural diversity in a deficit model, failure to show empathy with students from different cultural backgrounds, the assumption of a â samenessâ among international and domestic students, and stress to assimilate into the dominant culture in the public sphere contribute to the pressure faced by international students.
Personality Facets in Patients with Major Depressive Disorder: Differential Change across Treatment and Association with Relapse and Recurrence
Keywords: Antidepressant Medication
Cognitive-Behavioural Therapy
Depression
Five-Factor Model
Interpersonal Psychotherapy
Personality Facets

Personality assessed at a higher-order, “domain” level has shown to be predictive of the treatment response and course of major depressive disorder (MDD). Personality domains have also shown mean-level change (i.e., absolute change) and rank-order stability (i.e., relative stability) across treatment. The nature and prognostic significance of personality change at a lower-order, “facet” level has yet to be evaluated. The present study investigated absolute and relative change of personality facets across cognitive-behavioural therapy (CBT), interpersonal psychotherapy (IPT), and antidepressant medication (ADM) for MDD, and the effect of personality change and pre-treatment personality traits on relapse/recurrence. A total of 150 outpatients with the MDD were randomized to receive either CBT, IPT, or ADM. Remitted patients (n = 92) were assessed on a weekly basis for a maximum of 18 months following treatment. Findings support absolute change and relative stability of personality facets, indicating that both components of personality have prognostic significance.
Changes in Neural Systems Underlying Response Inhibition in Patients with BPD After Six Months of Dialectical Behaviour Therapy
Keywords: Borderline Personality Disorder
Dialectical Behavior Therapy
Functional Near-Infrared Spectroscopy
Prefrontal Cortex
Response Inhibition
Self-Harm

Borderline Personality Disorder (BPD) is a highly prevalent mental disorder, characterized by impulsive behavior (e.g., self-harm). However, the neural basis of treatment-related change in BPD is yet to be fully explored. The present study examined the neural correlates of inhibitory control within the prefrontal cortex (PFC) in 29 self-harming patients with BPD who underwent approximately six-months of Dialectical Behavior Therapy (DBT). Pre-treatment, patients demonstrated lower activation bilaterally and higher activation medially in the PFC. After approximately six-months of DBT, patients demonstrated higher activation in the bilateral regions of the PFC and also in the right medial PFC. These activation patterns were also associated with improvements in BPD symptom domains. Additionally, differences in patterns of activation in patients who completed six months of treatment versus those who dropped out or did not initiate treatment were also explored. These findings provide insight into neural mechanisms underlying treatment-related symptom change in BPD.
Tea, Toast and Red Lipstick: Understanding Perceptions of Food, Body Image and Age in Older Women
Keywords: age
body image
food
life history
older adults
women

Though life history methodology, I explore the question: what do the life histories of older women reveal about how lived experience influences perceptions of food, body image and age? The purpose of this research is to develop a deeper understanding of food, body image and age, as it relates to women over 70 years of age; a context infrequently explored in this generation of women and therefore, underrepresented in the literature. It also facilitates a healing process for my personal struggles. In committing to the defining elements of life history research, the stories of Sam and Lina are explored with intentionality, reflexive writing, holistic quality, communicability, aesthetic form and with respect and appreciation for the knowledge life history brings to our broader social context (Cole Knowles, 2001). Themes, such as family relationships, peer influence, life achievements financial stability and the effects of a decline in health are explored.
Outcrop Based Facies and Architecture Analysis of the Regional Intertonguing of Early Jurassic Kayenta Formation with the Navajo Sandstone, Kanab Canyon, Utah
Keywords: Eolian sedimentology
Fluvial sedimentology
Utah

The establishment of the extensive Navajo erg can be identified in the Lower Jurassic rocks of the Kanab Canyon area by three distinct and successively thicker advances over the marginal fluvial Kayenta. A total of 15 fluvial and eolian facies were identified based on several vertical sedimentological logs. The facies were summarized in four main facies associations, representing multistorey braided fluvial channels, unconfined ephemeral fluvial sandsheets, erg margin and eolian dune depositional settings. The eolian units have a consistent paleoflow towards the east, which opposed the fluvial paleoflow towards the west. Fluvial architectural element analysis was completed in four lateral outcrop profiles. Additionally, two lateral architectural profiles were completed within the eolian units. Based on systematic vertical facies association transition and overall decrease in fluvial energy upsection, three drying-up trends were identified. These trends are proposed to be correlative across the basin and likely represent climatic cycles.
DEVELOPING A TEXT MESSAGING INTERVENTION TO SUPPORT MEDICATION ADHERENCE TO ENDOCRINE THERAPY IN ADJUVANT BREAST CANCER: AN INTERPRETIVE DESCRIPTION APPROACH
Keywords: breast cancer
endocrine therapy
intervention development
mHealth
text messaging

Most adjuvant breast cancer patients are prescribed long-term endocrine therapy; however, not all patients continue these medications long term. Text messaging programs have been shown to be a low cost means of increasing medication adherence in a wide variety of chronic conditions, but have not been extensively studied in the breast cancer setting. The primary objective of this study was to develop a text messaging intervention to support long term endocrine therapy adherence. First, we sought to understand the breast cancer survivorship experience in the context of endocrine therapy. Second, we were interested in womenâ s experiences when using a theoretically grounded text messaging intervention. Participants were recruited from a single large academic centre. The initial text messaging intervention was informed by the Medication Adherence Model. Data collection comprised of two semi- structured interviews with eight participants, as well as enrollment in the text messaging intervention. Two main themes arose regarding the experience of breast cancer survivorship. First, fear of recurrence and the worry about returning to normal after breast cancer treatment were dominating emotional experiences. As a result, a high degree of uncertainty permeated their lives, and learning to manage uncertainty was identified as a critical coping skill. When participants were asked regarding preferences for a text messaging intervention, women stated they were interested in an intervention that would act as a supporting friend, sending positive messages about overall wellness. In addition, message tailoring was recognized as an important characteristic in order to increase program usefulness. These findings are useful in shaping future work ensuring long term medication adherence to endocrine therapy.
Characterization and Modification of the Zinc Sensor ZapCY2 for Improved Nickel Binding
Keywords: Bacteria
FRET
Nickel
Protein
Sensor

Nickel is an important element needed for the function of many microorganisms, including several strains of pathogenic bacteria such as Escherichia coli and Helicobacter pylori. The free intracellular nickel concentration has not been quantified for any microorganism, and such information would be very beneficial for understanding the biochemistry of pathogenic bacteria. This research aims to develop an intracellular FRET-based nickel sensor for this purpose. A previously designed zinc sensor, ZapCY2, was selected to undergo characterization and modification in an effort to tune its selectivity to favor nickel. Cysteines in the metal-binding sites were substituted with histidine or aspartic acid. Characterization of the variants revealed a 15-30 fold reduction in the affinity for zinc, and an unchanged affinity for nickel. Additional modifications will be required to further improve the sensorâ s response towards nickel.
Application of High-order Summation-by-parts Operators to the Steady Reynolds-averaged Navier-Stokes Equations
Keywords: High-Order Methods
Turbulence Modelling

Third- and fourth-order methods have been implemented to solve the steady Reynolds-averaged Navier-Stokes equations with the Spalart-Allmaras turbulence model. Summation-by-parts operators are used for spatial discretization along with simultaneous approximation terms to enforce boundary and interface conditions in a weak sense. Two validation cases are tested to verify the high-order implementation of the turbulence model and to examine the efficiency and robustness of the high-order methods. It is shown that the third-order method generally produces the most accurate results on a given mesh. The use of the fourth-order method also shows the potential of increasing numerical accuracy over the second-order method on coarse meshes. In terms of computational cost, the results demonstrate that the high-order methods are more efficient as the same level of accuracy can be achieved within less computational time on a coarser mesh.
Body Composition of Infants with Gastroschisis Assessed by Air Displacement Plethysmography
Keywords: Air Displacement Plethysmography
Body Composition
Gastroschisis
Infants
Nutrition
Pediatrics

Background: Measuring body composition (BC) in infants enables monitoring their growth pattern. Air displacement plethysmography (ADP), a BC technique that is practical for infants, but has not been adequately assessed in different infant populations. Objective: To demonstrate the suitability of the ADP in a high-risk population and to evaluate their BC. Methodology: The study was observational; subjects were recruited from the Hospital for Sick Children. A total of 12 Infants â Ľ 33 weeks corrected gestational age at birth, diagnosed with gastroschisis, were studied. BC was measured post-surgery and a month thereafter. Results: fat mass (FM) did not show a significant difference in our study group compared to healthy infants at both measurements. However, fat free mass (FFM) was significantly lower in our study group than healthy infants at both measurements. Conclusion: There were no procedure-related complications. A smaller gain in FFM than expected was shown in this group of patients.
A Design Framework for Collective Inquiry Learning Environments
Keywords: Collective Inquiry
Computer-Supported Collaborative Learning
Educational Technology
Human-Computer Interactions
Interaction Design
Technology-Enhanced Learning

This thesis describes a design-based research study of a recent KCI implementation in a whole-class inquiry elementary science curriculum called WallCology, focusing on the interaction design aspects of its technological support. From that, the thesis builds a framework for HCI design for the specific context of Knowledge Community and Inquiry (KCI), a CSCL model that guides the design of collective inquiry curriculum in which students work together to advance their collective progress on a set of well defined learning goals. This design framework comprises a series of conceptual design principles, guidelines for implementing a visual language for interface design, and an ontology of human-computer interactions that could emerge in a KCI enactment, with examples of GUI design solutions to support them.