VictorJuiz/thesis huggingface dataset:
Public Health Financing in British Columbia: A Case Study Investigating Factors Influencing Decision-Making
Keywords: British Columbia
Budgeting
Financing
Funding
Health Policy
Public Health

To address the gap in research on public health financing in Canada, this study aimed to 1) describe public health budget-setting processes in British Columbia (BC), including roles of stakeholders involved, and 2) identify and analyse the factors influencing decision-making for public health resource allocation. My case study of the BC public health system consisted of a jurisdictional review of academic and grey literature on BC financing processes and trends spanning two decades, and semi-structured interviews with 14 key informants influential in budget-setting for public health. Taking an inductive analytical approach, I constructed a conceptual model of the political, structural, and external factors influencing public health financing decisions based on results from the case study. I conclude by identifying policy directions with potential for promoting stable public health funding, such as including public health experts in financial decision-making, and strengthening partnerships with external public health organizations. Pour répondre au manque de recherche sur le financement de la santé publique au Canada, cette étude a visé à 1) décrire les processus budgétaires de santé publique en Colombie Britannique (CB) en incluant les rôles des parties prenantes, et 2) identifier et analyser les facteurs influant la prise de décisions pour l’allocation de ressources à la santé publique. Mon étude de cas du système de santé publique de la CB a consisté en une revue juridictionnelle des littératures académique et grise sur les processus et tendances de financement en CB au cours des deux dernières décennies, et de 14 entrevues semi-structurées avec des participants clés influant l’élaboration du budget de santé publique. En prenant une approche analytique inductive, j’ai construit un modèle conceptuel des facteurs politiques, structurels, et externes influant les décisions de financement de la santé publique basé sur mes résultats de l’étude de cas. Je conclus en identifiant des options politiques avec le potentiel de promouvoir un financement de santé publique stable, telle qu’inclure les experts en santé publique dans la prise de décisions, et de renforcer les partenariats avec les organisations de santé publique externes.
Comparing Sampling Methods for Measuring Atmospheric Microplastics in Rural and Urban Sites, using Laser Direct Infrared Spectroscopy (LDIR)
Keywords: Anthropogenic Fibre
Atmospheric Deposition
Atmospheric Pollution
Method Comparison
Microplastic

In recent years, there have been growing concerns regarding atmospheric-related microplastics and anthropogenically sourced particles. Atmospheric transport disperses these particles quickly and worldwide, deposition being an important source to terrestrial and ocean surfaces. Traditional air sampling methods were deployed and compared during this study, to investigate atmospheric-related microplastics and anthropogenically sourced particles using; active-air, bulk deposition, and wet deposition. Samples were deployed in a densely populated urban centre and at a rural site, between February 2022 and February 2023. Number of particles and diversity of polymer type and morphology were higher at the urban site. There was no statistical difference between the sampling methods used at either site. This implies the simple bulk deposition samplers can be confidently used to determine abundance and the diversity in polymer types and morphology in ambient air. The dominant polymer types at both sites were polyester, polypropylene, and anthropogenic cellulose (e.g., denim, cellulose acetate, etc.).
The Effect of Full-Fat Dairy Consumption on Body Weight, Body Composition, Energy Metabolism, and Blood Lipids
Keywords: Blood Lipids
Body Composition
Dairy
Energy Metabolism

The hypothesis was that the addition of full-fat dairy combined with dietary advice based on Canada’s Food Guide would result in greater loss of weight and improved health markers in overweight and obese adults compared to an energy restricted diet. Three daily servings of full-fat dairy of milk, cheese, and yogurt were added to an energy restricted or ab libitum diet without energy restriction and compared to a low-dairy energy restricted diet in 65 healthy males and females. The design was a 12-week, randomized, parallel, multi-site study. Dietary treatments had no effect on body weight, body composition, waist or hip circumference, resting metabolic rate, or blood lipid concentrations, including LDL cholesterol and triglycerides. The results encourage further examination of the effects of full-fat dairy in the context of Canada’s Food Guide.
Waterborne 2-Component Polyurethane Coatings Based on Acrylic Polyols with Secondary Alcohols
Keywords: Polyurethane
Two component polyurethane
waterborne coating

While two-component waterborne polyurethane (2K-WB-PUR) coatings offer an environmentally friendly alternative to their solventborne counterparts, their performance is subpar in comparison to solventborne coatings. Characteristics of the components affect the miscibility and the formation of the film in ways which are not well understood. In this thesis, I investigated the film formation of a two-component waterborne polyurethane system comprised of an acrylic polyol with secondary hydroxyl groups (Mn ≈ 5100, 10300 or 12900 g/mol, Ð ≈ 3, Tg ≈ 20 °C) and a hydrophilically modified polyisocyanate (Basonat HW1000). I followed the film formation using spectroscopic techniques and found that higher molecular weight polyols limited the extent of molecular mixing in the film and lead to a higher relative ratio of polyurea to polyurethane in the film.
Generation of Backward-Looking Complex Reflections for a Motivational Interviewing-Based Smoking Cessation Chatbot using GPT-4
Keywords: artificial intelligence
chatbot
motivational interviewing
natural language processing
smoking

Motivational Interviewing (MI) is a validated therapy for behavioural change that has shown success in helping smokers reduce or quit their smoking. The development of conversational agents that can guide a client through an MI therapeutic conversation may help increase the accessibility of MI across a wider populations of smokers. In the MIbot project a chatbot, named MIBot, aims to guide clients towards the decision to quit smoking, by MI-style reflections generated with a Transformer-based neural net architecture. Current iterations of MIBot have focused on the generation of both simple and complex reflections in a 5-question conversation, but these reflections are limited to the context of the immediate prior utterance of the client, and do not incorporate a client’s utterances from earlier in the conversation by themselves. In this work, we introduce the concept of the backward looking complex reflection (BLCR) which does incorporate earlier utterances as a relevant basis for a reflection. We present a method to automatically generate BLCRs using the prompting capabilities of Large Language Models (LLMs) such as GPT-4. To assess the effectiveness of this method, we generate 150 BLCRs over real MIBot-Client conversational interactions, and use a 4-point BLCR Rating Scale that measures the quality of a BLCR as assessed by three independent human raters. The results of this experiment indicate that an average of 88% BLCRs generated by this method were deemed acceptable, and all three raters agreed on these scores at least 80% of the time. We present examples of the generated BLCRs, make comparisons to earlier versions of MIBot reflections to display qualitative improvement.
The Transdermal Delivery of 1α,25-Dihydroxyvitamin D3 to Treat Secondary Hyperparathyroidism in Chronic Kidney Disease
Keywords: calcitriol
chronic kidney disease
secondary hyperparathyroidism
transdermal
transdermal patch

Impaired renal formation of 1α,25-Dihydroxyvitamin D3 (1,25D) due to chronic kidney disease (CKD) is the primary cause of secondary hyperparathyroidism (SHPT) in CKD. Current 1,25D formulations are indicated only in advanced CKD due to risk of hypercalcemia. By delivering 1,25D via a transdermal patch, we aim to reduce hypercalcemia risk while effectively treatingSHPT. Methods: Utilizing 1,25D transdermal patches in a mouse model of CKD, single and repeated dose studies were conducted with 0.0048%w/w and single dose with 0.001%w/w strength patches. Results: 0.0048%w/w patches reduced parathyroid hormone (PTH); however, hypercalcemia arose. 0.001%w/w patches increased PTH via rebound once the concentration gradient from the patch to systemic circulation depleted. Conclusion: Hypercalcemia was not prevented by the patch. However, transdermal 1,25D delivery may be a viable option to treat SHPT in CKD by selecting a more representative CKD animal model and optimization of strength, dosing regimen and stability of the current formulation.
Adapting Muscle Endogenous Repair (MEndR) Assay for Academic and Industry Adoption
Keywords: Endogenous repair
Muscle stem cell
Skeletal muscle
Tissue engineering

Skeletal muscle is an essential tissue and in healthy individuals it can self-repair through the activity of muscle stem cells (MuSCs). In age and disease, MuSC endogenous repair proficiency is lost, and therapeutics that target and restore functionality are of interest. However, in vivo validation of drugs with potential to stimulate muscle endogenous repair proves to be a bottleneck in drug discovery and to address this problem we developed a MuSC mediated skeletal muscle endogenous repair (MEndR) phenotypic culture assay that predicts gold-standard in vivo assay outcomes. Roadblocks exist that prevent scale-up, and assay adoption. My thesis addresses two issues: phenotypic data analysis and the use of cells with access and scale-up limitations. My thesis offers a semi-automated pipeline to analyze MuSC-derived myotubes from confocal images with the power to stratify MuSC drug treatment response. I also identify immortalized myoblast cell lines with which to engineer the muscle templates.
A Hardware Accelerator for Fully Homomorphic Encryption based Machine Learning Applications
Keywords: ASIC
Fully Homomorphic Encryption
Machine Learning

Fully homomorphic encryption (FHE) is a lattice-based cryptography scheme that enables mathematical operations to be performed on encrypted data without first having to decrypt the data, allowing for the implementation of secure machine learning (ML). As performing ML applications with FHE-encrypted data using current processors can take significant computation time, DARPA has created the DPRIVE challenge for the design of an FHE hardware accelerator. In this thesis, we design and verify through a cycle-accurate Verilog model both residue number system (RNS) and large arithmetic word size (LAWS) implementations of a hardware accelerator capable of realizing the DPRIVE performance specifications for 1024-point logistic regression using the Cheon-Kim-Kim-Song (CKKS) mathematical foundation. We show that the two implementations achieve comparable execution time performance, and that the estimated CMOS ASIC implementation area of the LAWS design requires only 68% of the core area of the equivalent RNS design in an equivalent technology node.
Development of Xylitol-based Formulations as Novel Alternatives for Surgical Site Preparation Agents
Keywords: surgical site infections
surgical site preparation
xylitol

Xylitol has numerous applications. We hypothesize that when used as a surgical site preparation agent, xylitol will significantly reduce the bacterial load on a given area of skin. We developed a protocol to test the ability of xylitol to inhibit the growth of, and eradicate, Staphylococcus aureus. Preclinical studies revealed that planktonic growth was inhibited by the supplementation of 40% (w/v) xylitol, with a noted 2-log fold reduction in planktonic cell survival. Biofilm growth was inhibited when cultivated in xylitol concentrations above 30% (w/v). Biofilms were eradicated when exposed to 40% xylitol, or to 40% xylitol/10% isopropyl alcohol. In clinical studies, baseline bacterial counts were inadequate. Therefore, xylitol could not be assessed as a surgical site preparation agent. Our preclinical findings suggest that 40% xylitol, or 40% xylitol/ 10% IPA can significantly reduce the growth, biofilm formation and eradicate mature biofilms of S. aureus.
Impact of Exogenous Hydrogen Sulfide on Short-term Synaptic Plasticity in the Anoxia-tolerant Western Painted Turtle
Keywords: Electrophysiology
Hydrogen sulfide
Rhodamine
Short-term synaptic plasticity
Synaptic transmission
Western painted turtle

The western painted turtle has evolved mechanisms that allow for survival during months of severe hypoxia without neuronal damage. This is achieved by suppressing metabolism and excitatory neuronal activity. What remains unclear, however, is what happens at the synaptic level and what signalling molecules regulate synaptic activity during hypoxia. Hydrogen sulfide (H2S), a gasotransmitter, participates in neuroprotective pathways and is found to accumulate in the neuronal tissue during low O2 conditions. I hypothesize that H2S modulates synaptic transmission during hypoxia in the turtle brain. Using cortical tissue, I demonstrated that exogenous H2S application: 1) causes mitochondrial membrane depolarization similar to severe hypoxia; 2) and when combined with hypoxia does not affect synaptic transmission and short-term plasticity and 3) does not impact the membrane potential of pyramidal neurons as severe hypoxia is known to do. These findings indicate that synaptic transmission and short-term plasticity are maintained during hypoxic conditions.
Neutrophil Development and Function in a Murine Model of Severe Acute Malnutrition
Keywords: Acute Inflammation
Anti-Microbial Functions
Cellular Differentiation
Malnutrition
Mouse Model
Neutrophils

Severe malnutrition is associated with life-threatening complications and underlies morbidity and mortality in children under five. Immune dysregulations, especially of innate immunity, underlies these adverse outcomes. I used a lipopolysaccharide (LPS)-challenged protein restriction mouse model to investigate the impact of malnutrition and acute inflammation on neutrophil biology, the first responders of innate immunity that remain understudied in malnutrition. Following LPS, the malnourished mice were more susceptible to disease and mortality. Neutrophils (Ly6G+ cells) were expanded in the lungs of malnourished mice. However, neutrophil-mediated ROS production was reduced. Gene expression of transcription factors was also reduced in the bone marrow of these mice. These transcription factors control the gain of neutrophil effector functions throughout development. Therefore, this evidence points to changes in the neutrophil-intrinsic program driving increased susceptibility of the malnourished mice to mortality following acute inflammation. Overall, this study provides a novel understanding of neutrophil responses in malnutrition and inflammation.
Design and Manufacturing of an Encapsulation for a High-temperature Ultrasonic Transducer
Keywords: Design
Nondestructive testing
Transducer
Ultrasound

This thesis describes the design and manufacturing of an encapsulation for a high-temperature ultrasonic transducer to operate in the temperature range of 25℃ to 650℃. The internal transducer components are a lithium niobate piezoelectric crystal, a porous zirconia attenuative backing layer, a stainless steel matching layer, and annealed silver foils as the ultrasonic coupling agents. An encapsulation design was proposed to comply with the specifications set by an industrial partner. This design was then modeled in the COMSOL Multiphysics® finite element package to analyze its mechanical and ultrasonic behavior. After design refinements, a prototype transducer was developed and tested in the temperature range of 25℃ to 650℃. Ultrasonic echo signal produced by the prototype had a Signal-to-Noise ratio (SNR) of ~31 dB and half-power (-3 dB) bandwidth of ~70%.
Characterization of Abscisic Acid Transport in Arabidopsis thaliana and Brassica napus
Keywords: Abscisic Acid
Abscisic Acid Transport
Arabidopsis thaliana
Brassica napus
Positron emission tomography

The phytohormone abscisic acid (ABA) plays an important role in regulating numerous plant processes such as seed maturation, seed dormancy, and stress responses. These regulations require the long-distance movement of ABA in plants, which has been documented and requires a proper network of ABA transporters. Positron Emission Tomography (PET) in planta allows a real-time and non-destructive method for studying the movement of small molecules using a radiotracer. We show that 3’-F-ABA displayed similar bioactivity as ABA via ABA-responsive β-glucuronidase (GUS) reporter expression in Arabidopsis thaliana. In addition, the destructive phytochemical analysis of Brassica napus plants co-applied 3’-F-ABA and deuterium-labeled ABA (d6-ABA) showed a similar distribution pattern. Arabidopsis transporter mutants (abcg25, abcg40, ait1) showed delayed GUS expression in shoots which suggests that ABCG25, ABCG40, and AIT1 are required for the quick transport of ABA from root to shoot. Lastly, several ABA analogs were found to be candidates for ABA transport inhibitors.
Developing a DNA Origami Based In Vitro Antigen Presentation Platform
Keywords: B cell receptors
B cells
DNA Nanotechnology
DNA Origami
Immunology

DNA Origami is a novel tool with the capacity to generate arbitrary shapes at the nanoscale. A powerful application of this technique has been to interrogate the nanoscale dynamics governing immune cell triggering. B cells are a major component of the adaptive immune system, whose primary roles are to directly participate in immune responses through antibody production, and by augmenting T cell responses. However, the exact requirements of nanoscale antigen organization driving B cell triggering remain poorly characterized. We sought to address this gap, by harnessing the programmability of DNA origami to establish an in vitro reconstitution platform for antigen presentation on a supported lipid bilayer (SLB) system. In a cellular context, we found that BCR microclusters were efficiently generated, and that their production was correlated with antigen concentration. Future work will be aimed at further developing this platform to refine the precision of its antigen presentation capabilities.
The Use of Primary Care Electronic Medical Record Data in the Prediction and Identification of Health Service Use
Keywords: electronic medical record
emergency department
health prevention
hospitalization
predictive analytics
primary health care

Primary health care (PHC) services play an essential role in reducing health system burden, including within emergency departments (ED) and hospitals. The longitudinal nature and population-based approach of primary care contributes to electronic medical record (EMR) data which is a rich source of information on patients and health service use. A review of theliterature on using primary care EMR data to predict ED visits, hospitalizations, and mortality was conducted. Thirty-one studies were included, and several common elements were identified to contribute value to the prediction of health service use. Next, case-finding algorithms to identify hospitalizations and ED visits were developed and validated within PHC. The best performing algorithms for hospitalizations demonstrated good agreeance with reference standards (ICC = 0.71-0.78) and excellent agreeance for ED visits (ICC = 0.87-0.92). This research provides a foundation for advancing the use of primary care EMR data to predict health service use and outcomes.
Benchmarking the Robustness of Deep Learning Segmentation Models to Out-of-distribution and Corrupted Data in MR Neuroimaging
Keywords: Benchmarking
Corruptions and artifacts
Generalizable deep learning
MRI
Out-of-distribution data
Segmentation

A principal challenge in the large-scale deployment of deep neural networks (DNNs) in neuroimage analysis is the potential for shifts in signal-to-noise ratio, contrast, resolution, and presence of artifacts (i.e., distribution shifts) from site to site due to variances in scanners and acquisition protocols. Currently, there are no benchmarking frameworks to assess the robustness of DNN-based models to distribution shifts in MRI, and accessible multi-site benchmarking datasets are still scarce or task-specific. To address these limitations, we develop a platform providing modules for generating benchmarking datasets using transforms that model distribution shifts in MRI and newly derived benchmarking metrics. We apply our methodology to hippocampus, ventricle, and white matter hyperintensity segmentation in several large studies, demonstrating that modern DNNs are highly susceptible to distribution shifts in MRI and that data augmentation strategies and architectural design considerations (e.g., U-Nets vs. transformer-based models) have significant implications for robustness to particular transforms.
Monitoring and Controlling Respiratory Effort in Acute Hypoxemic Respiratory Failure
Keywords: Acute hypoxemic respiratory failure
Lung and diaphragm protective ventilation
Respiratory effort
Ventilator induced diaphragm dysfunction
Ventilator induced lung injury
VV-ECMO

Ventilation and sedation are used to manage acute hypoxemic respiratory failure (AHRF), but their individual and interactive effects on respiratory effort (|∆Pes|) and lung-distending pressure (∆PL,dyn) are unknown. This is a secondary analysis of a trial of a lung- and diaphragm-protection strategy in patients with AHRF, where ventilator settings and sedation were systematically manipulated to optimize |∆Pes| and ∆PL,dyn. The study showed that propofol attenuates |∆Pes| and ∆PL,dyn. Sedation with fentanyl was associated with lower respiratory drive, but not with lower respiratory effort. Increasing inspiratory pressure also attenuated |∆Pes|, but not ∆PL,dyn. The effect of inspiratory pressure varied according to the propofol dose: increasing inspiratory pressure resulted in higher ∆PL,dyn in patients receiving higher propofol dose. Patients on VV-ECMO had lower |∆Pes| and required lower propofol dose to control respiratory effort. This study highlights the complex interactions between interventions to modulate respiratory effort and provides insights on optimal management strategies.