VictorJuiz/thesis huggingface dataset:
Modelling and Experimental Validation of a Sponge Filter in a Column System
Keywords: adsorption
applied engineering
column system
computational fluid dynamics
oil spill
porous media

Oil spills can damage the marine environment, local populations, and impact tourism. By adding an in-situ filtration step to the existing skimming process, it is possible to improve the oil spill response times dramatically. This thesis examines surface engineered sponges implemented in a flow through column configuration as a potential filtration technology for this application. A lab scale column system is developed to investigate the impact of temperature, flow rate, and emulsion concentration on the oil adsorption. The results of the experiments are used to develop a computational fluid dynamics model. Results show that the column system can achieve a maximum adsorption of 0.0022 kg/g and adsorption rate of 1.1 g/(kg-s) when run at a flow rate of 300 ml/min. The computational fluid dynamics model shows that the technology can be scaled for skimming vessel operation, increasing utilization by 75% over current practice when implemented in a continuous processing mode.
Decentralized Oracles and Network Economics in Modern Blockchain Systems
Keywords: Blockchain
Blockchain oracle

As blockchain technology opens up opportunities with the popularization of decentralized applications, many problems are left to address. Firstly, blockchain systems rely on oracles to bridge external information to the decentralized applications. However, many existing oracle designs either express strong dependency on trusted third parties, or limit the query to very specific formats such as a web API. This thesis describes a novel oracle protocol based on the Astraea protocols and a peer-prediction mechanism. The proposed oracle is capable of extracting subjective data truthfully and discouraging Sybil attacks. Secondly, Proof-of-Work blockchains depend on proper economic incentive designs for miners to faithfully maintain the network in a sustainable way. This thesis describes how the economic engineering of the Conflux Network, a high throughput proof-of-work blockchain, leads to sound economic incentives that support desirable and sustainable mining behavior.
From Bathtubs to Bloodfeeders: An Evolutionary Study of the Aphaproteobacterial Gellertiella (formerly Ca. Reichenowia)
Keywords: B vitamin synthesis
Endosymbiosis
Leech
Metabolic pathways
Nutrient provisioning
Phylogenomics

Many leeches are blood feeders and host bacteria within specialized organs. One example is Placobdella which hosts the alpha-proteobacterial Candidatus Reichenowia. It is assumed that Reichenowia provisions Placobdella with B vitamins. Although Reichenowia consistently places within Rhizobiaceae, its free-living relative remains a mystery. By obtaining genome sequences of the endosymbiotic bacteria of six species of Placobdella, I address questions regarding the role of Reichenowia and its origin. B vitamin synthesis pathways remain largely intact across all taxa with many gaps likely representing a lack of knowledge concerning alternate synthesis routes. I find robust and consistent support for the nesting of the free-living Gellertiella hungarica within Reichenowia, necessitating the dissolution of Reichenowia. The topology of this clade suggests two independent origins of endosymbiosis from a G. hungarica-like ancestor. These findings clarify the ecology of the system and point towards a potentially novel model system for investigating the early stages of endosymbiosis.
Race and Contemporary (Post)feminism: Expanding Theory and Feminist Practice in Gender-based Violence Media Activism
Keywords: counter violence
feminist resistance
gendered violence
intersectionality
media activism
postfeminism

This study focuses on recent public calls for a sex strike made by actress and activist Alyssa Milano and other contemporary resistance strategies by public female figures like Me Too founder Tarana Burke and executive producer of Surviving R. Kelly dream hampton. This study explores how race, class and access to the public sphere shape contemporary counter violence in the United States and Global North. This study uses a variety of published, publicly-accessible documents including interviews, social media posts and articles to qualitatively analyze the racial and class politics of contemporary counter violence strategies. Employing a conceptual framework grounded in intersectional feminist theory and existing literature regarding gendered and sexual violence, this study conveys the limitations of contemporary (post)feminist and white celebrity pop cultural counter violence media activism. This study contextualizes the politics of violence beyond a gender-only lens to expand feminist theory and practice within contemporary counter violence activism.
Improving the Performance of Membrane Electrode Assembly CO2 Electrolyzers
Keywords: Carbon dioxide electrolyzer
Membrane electrode assembly
Neutron imaging
Overvoltages
Synchrotron X-ray imaging

Detrimental ohmic and mass transport overvoltages experienced by the membrane electrode assembly (MEA) CO2 electrolyzer pose critical barriers to the transition from lab scale to large scale operation. The operating temperature was found to be a critical parameter for improving the performance as the power density was reduced by up to 35 % when increasing the temperature from 25 °C to 60 °C. At low current densities, increasing temperature also led to a 7 fold reduction in ohmic resistance. At higher current densities, overvoltages were dominated by distinct mass transport limitations at the gas diffusion electrodes. Additionally, a high current density of 755 mA/cm2 was reached by fully humidifying the reactant CO2. The power density was reduced by up to 30 % as a result of a 4-fold decrease in ohmic losses. The findings of this thesis provide valuable insights for achieving higher current densities at low cell voltages for CO2 electrolyzers.
Chondrocyte Migration from Bioengineered Cartilage
Keywords: Articular Cartilage
Cartilage Integration
Cell Migration
Chondrocyte
Platelet-Rich Plasma
Tissue Engineering

Platelet-rich plasma (PRP) treatment enhances the integration of bioengineered cartilage to host cartilage, which involves cell migration into host cartilage. This study hypothesizes that PRP treatment of bioengineered cartilage supports chondrocyte migration and matrix accumulation by these cells in an in vitro 3D co-culture model. Osteochondral-like constructs were developed by culturing primary bovine or passaged human chondrocytes on a bone substitute which were then soaked in PRP and placed in co-culture with native osteochondral plugs. Controls were not pretreated with PRP. Cells from bovine and human bioengineered cartilage migrated onto fibre networks formed by PRP. However, only the bovine cells had the ability to form hyaline cartilage-like tissue, but this required cell migration from the bone. Cells did not migrate out from the human osteochondral plugs. This thesis demonstrates that cartilage implant integration is likely a complex process. This model system can be used to facilitate future investigations.
The Relationship between Cardiac Rehabilitation and Long-term Outcomes in a Post CABG Population – A Clinical and Administrative Database Study
Keywords: Cardiac Rehabilitation
Coronary artery bypass grafting (CABG)
Outcomes research
Secondary prevention
Survival

This is a single center retrospective study of 5,000 patients evaluating the effect of cardiac rehabilitation on long-term outcomes following coronary artery bypass surgery. A multivariable Cox proportional hazard model showed that cardiac rehabilitation was associated with a reduction in the composite of all-cause mortality, acute myocardial infarction, stroke or repeat revascularization, hazard ratio (HR) 0.83, 95% confidence interval (CI) 0.75-0.91, p
Laws in Action Within Schools (LAWS): A Program Evaluation
Keywords: Access program
Canada
Contingent Students
LAWS
Magnet vs. Access
Toronto District School Board

Access to postsecondary education is seen as a problem that has largely been solved in Canada, yet when one delves deeper, it is clear that many groups are still under-represented. This thesis undertakes a secondary data analysis to evaluate one access program, Law in Action within Schools (LAWS). The program runs both curricular and extracurricular programming to engage and encourage at-risk students in secondary schools in the Toronto District School Board. The program continues to provide gains in grades and access. LAWS students have greater access to universities and colleges post-graduation at 75% on average, compared to non-LAWS students who access at a rate of less than 50%. Further exploration of the individual characteristics of participating schools would be of benefit, allowing the program to continually recalibrate enrolment practices to accommodate changing demographics to ensure that it remains an access program for students who otherwise would not access postsecondary education.
The Role of Arrestin-3 in Bone Catabolic Response to Hyperparathyroidism
Keywords: Arrestin
Bone
Hyperparathyroidism
Parathyroid Hormone

Primary hyperparathyroidism is characterized by elevated parathyroid hormone (PTH) levels and hypercalcemia, causing bone loss and fragility. PTH activates the PTH receptor (PTH1R), which primarily couples to Gαs, stimulating downstream effectors. Previously, we have seen trabecular anabolic effects of hyperparathyroidism in mice overexpressing Gαs. We hypothesized that increased Gαs protein levels in osteoblasts outcompete β-arrestins binding to PTH1R, leading to reduced signal termination and increased bone formation. In this study, we tested whether β-arrestin2 deletion results in an anabolic response to hyperparathyroidism. While wild-type male mice exhibited a bone catabolic response, female mice were resistant. Contrarily, β-arrestin2 knockout male mice maintained bone whereas female mice exhibited an anabolic response. These results support our hypothesis that arrestin-mediated PTH1R downregulation contributes to bone loss associated with hyperparathyroidism. This offers new insight into the mechanism of bone loss in primary hyperparathyroidism that could be a path for drug therapy.
Evaluation of an In-patient Exercise, Relaxation, and Music Therapy Program for Allogeneic Hematopoietic Stem Cell Transplant Patients
Keywords: Allogeneic
Evaluation
Exercise
Music Therapy
Relaxation
Stem Cell Transplant

Exercise, relaxation, and music therapy interventions have shown to improve the physical function and psychological well-being of cancer survivors. However, few hospitals have integrated these interventions as standard of care. Objective: To evaluate the feasibility and effectiveness of the Rehabilitation Group Classes (RGC), an in-patient exercise, relaxation, and music therapy program for allogeneic hematopoietic stem cell transplant (allo-HSCT) patients. Methodology: The RE-AIM framework was implemented to evaluate program feasibility (e.g., attendance, fidelity) and effectiveness (e.g., physical and psychosocial outcomes). Assessment of participants occurred at three time points: admission to the unit, discharge from hospital, and 100 days after transplant. Results: The RGC were safely delivered, attendance was high (82%), and participants were satisfied with the intervention. Barriers to attendance were related to fatigue, isolation, and transplant complications. Conclusion: Multimodal interventions are feasible in the in-patient allo-HSCT setting. Research exploring the institutional adoption of in-hospital rehabilitation programs is warranted.
Towards Noninvasive Prenatal Diagnosis using Digital Microfluidics
Keywords: digital microfluidics
DMF
NIPD
nonivasive
single cell

The objective of this project is to lay the foundation to develop a clinically relevant, risk-free process for noninvasive prenatal diagnosis from cervical mucus samples using digital microfluidics isolation of single cell for -Omics (DISCO).Starting from a cervical swab obtained from pregnant women, fetal cells trapped in cervical mucus were enriched and isolated. Antibodies best suited to identify fetal and maternal cells were found. Maternal cells were removed using density gradient centrifugal separation and immunomagnetic depletion targeting specific cell types to increase the proportion of fetal cells to one in five in the final enriched sample. Fixative methods were optimized to increase the number of fetal cells recovered. DISCO was used to isolate the fetal cells from the enriched sample, followed by whole genome amplification of the isolated cell. Initial results from Short Tandem Repeats analysis show a partial fetal signature in the final enriched sample.
The Role of Protein Degradation in Cell Size Regulation
Keywords: cell size
protein degradatoin

Cells of a given type are remarkably uniform in size. In fact, deviation from this uniformity can imply the onset of a neoplastic condition. Previous work suggests that, at the level of the individual cell, size homeostasis is regulated by both growth rate and cell cycle (G1) duration. Altering either growth rate or cell cycle length will cause the other to compensate to minimize changes to cell size. However, the mechanism of this growth rate compensation is unclear. The aim of my project is to characterize the underlying pathways implicated in this mechanism, specifically to examine whether changes in protein degradation could be the responsible for this response. Indeed, I found that increased protein degradation, specifically, increased clearance of K48 ubiquitinated proteins, followed changed in growth rate due to compensation.
Ferroptosis: A Novel, Iron-mediated Contributor to Placental Cell Death
Keywords: Cell death
Hypoxia
Iron
Placenta
Preeclampsia
Trophoblasts

Iron is an essential micronutrient for cell survival and growth yet understanding of this metal in physiological and pathological pregnancies remains elusive. Importantly, iron - alongside lipid peroxidation - has been identified as a driver of ferroptosis, a newly identified mode of cell death. Hence, we hypothesized that iron imbalance increases susceptibility of ferroptotic cell death in preeclampsia (PE). In our investigation, PE trophoblast layers demonstrated increased iron content, increased lipid peroxide by-product malondialdehyde (MDA) concentrations, and decreased antioxidant enzyme glutathione peroxidase 4 (GPx4) expression and activity. In vitro, JEG3 and cytotrophoblast-like H9 cells demonstrated similar alterations to iron homeostasis, GPx4 expression and activity, and lipid peroxidation when exposed to PE-like environments of hypoxia and iron overload. Notably, pharmacological agents deferoxamine and ferrostatin-1 reversed excess iron- and low oxygen-induced ferroptotic hallmarks. In conclusion, iron and oxygen-mediated ferroptosis may contribute to heightened rates of trophoblast cell death characteristic of preeclamptic pregnancies.
Freeze Concentration to Regenerate Concentrated Draw Solution (CDS) and Recover Water from Industrial Effluents
Keywords: Concentrated draw solution
Energy-efficient
Forward osmosis
Industrial water recovery
Layer freeze concentration
Sustainable

This work focuses on industrial water recovery using freeze concentration (FC) as a stand-alone water recovery process (part 1), and investigates the possibility of an integrated forward osmosis-freeze concentration (FO-FC) process (part 2). In part 1, A 3-L bench-scale layer freeze crystallizer was designed, and 0.5-1.5 m NaCl and MgCl2 solutions were used to mimic effluents from the mining and extractive metallurgy industries. A maximum impurity reduction of 82 % and 68 % can be achieved from 0.5 m NaCl and MgCl2 solutions, respectively. Agitation at 50 rpm significantly improved ice purity even at a high concentration of 1.5 m MgCl2. In part 2, the results showed that the regeneration of the 2-m MgCl2 concentrated draw solution can be achieved by adjusting the jacket temperature. The multi-step operation further improved ice purity by 14.6 % without sacrificing the CDS regeneration objectives.
Online Conflict: Exploring University Students' Views and Experiences
Keywords: face-to-face deliberation
online conflict
online deliberation
online disagreement
productive dialogue
reasoned debate

The increasing popularity of online, conversational media raises questions about their efficacy as platforms for rational debate and consensus-building in civic discourse. As a preliminary qualitative exploration, 24 university students were interviewed on their understanding of online deliberation and disagreement. Participants were asked about their online activities with regard to communication. They provided accounts of where and how conflict commonly arises online, what motivates it, and how it is handled. Their preferences for discussing differences with others online or face-to-face were explored, with many expressing doubts about the civility and productivity of online disputes and the resultant avoidance of them. Political topics were seen as especially contentious and alienating. Some found face-to-face disagreement to be emotionally demanding and appreciated the distance and buffering afforded by virtual channels. The results are discussed with regard to the potential of online communication as a medium for reasoned debate and deliberation within this demographic.
Developmental Screening using the Infant Toddler Checklist at 18 months and School Readiness as Measured by the Early Development Instrument
Keywords: Children
Developmental Screening
Early Development Instrument
Infant Toddler Checklist
School Readiness

Background: This study identified factors associated with a positive Infant Toddler Checklist (ITC) screen and examined the validity of the ITC in identifying vulnerability on the Early Development Instrument (EDI). Methods: Multivariable regression models were used to identify the factors and examine the construct validity of the ITC. Screening test properties were used to evaluate the predictive validity of the ITC, using the EDI as the criterion measure. Results: 10-13% of children had a positive ITC screen. Male sex, lower birthweight, income
Co-location of Deep Learning Jobs in GPU Clusters
Keywords: deep-learning
gpu
machine-learning
scheduling

Deep learning (DL) training jobs now constitute a large portion of the jobs in the GPU clusters. Following the success of deep learning in various domains such as natural language processing, image classification, and object detection GPUs have become the new member of the computing clusters. Due to various reasons, GPUs are highly underutilized in the production GPU clusters. In this thesis, we design a scheduler that uses co-location to improve the GPU utilization in these clusters. Using in-depth profiling of DL jobs, we provide metrics that guide us on the compatibility of different DL jobs. Using these profiling data we are able to achieve almost 2X speedup in the makespan when using co-location compared to the first-in-first-out baseline.
Maintaining the Carbohydrate-energy Deficit Following High-intensity Interval Exercise Improves Next-day Glycemic Control in Women
Keywords: Carbohydrate
Exercise
HIIT
Metabolism
Muscle
Physiology

The purpose of this study was to investigate the effect of carbohydrate-energy replacement after a single session of high-intensity interval training (HIIT) on glycemic control in women. In a randomized order, seven recreationally active women completed 3 trials in the mid-follicular phase of the menstrual cycle: 1) No exercise (CTL); 2) HIIT + post-exercise carbohydrate restriction (EX-LC); 3) HIIT + post-exercise carbohydrate replenishment (EX-HC). The following day, postprandial glucose responses and 24 h indices of glycemic control were measured in response to standardized meals using continuous glucose monitoring. We demonstrated lower next-day postprandial glycemia following breakfast (p
Pain Management During and Following Endodontic Treatment: Systematic Reviews and Network Meta-analyses
Keywords: efficacy
Endodontic treatment
irreversible pulpitis
local anesthetics
network meta analysis
pain

Objectives: To identify effective interventions for 1) achieving successful pulpal anesthesia during endodontic treatment; and 2) managing postoperative pain. Methods: We searched major databases. Two review authors selected studies and extracted data. Included studies were assessed by Cochrane risk of bias tool. Network meta-analyses (NMAs) were undertaken using the Bayesian random-effects framework to rank and estimate the treatment effects of the included interventions. Results: Out of 37 interventions of 46 studies, we identified supplemental intraosseous injection (IO) to be the most efficacious followed by supplemental buccal and lingual infiltrations using 4% articaine+preoperative NSAIDS. In eight of 11 studies, NSAIDs+acetaminophen and NSAIDs were the most effective for managing postoperative pain. Conclusion/significance: Supplemental IO using 2% lidocaine with or without pre-operative analgesic or 4% articaine were the most efficacious strategies to achieve pulpal anesthesia during endodontic treatment. Postoperatively, NSAIDs or NSAIDs+acetaminophen were the most effective.
Novel Idea-generation Approaches Applied to Wind-turbine Blade Repurposing
Keywords: Alternate Uses Task
Creativity
Wind-Turbine Blade

Many engineering problems still require novel solutions, e.g., the repurposing of retired wind-turbine blades. This work investigates novel idea-generation methods that aim to increase the viability of reuse ideas for the currently un-recyclable wind-turbine blade. The first half of this work stems from increasing evidence which suggests that recall of episodic memories enhances idea generation, however its application to engineering problems has been limited. Results show that strategies increasing access to episodic memory may improve flexible and elaborate idea generation for common objects and feasibility of reuses for wind-turbine blades. A follow-up study addressed the large scale of the blades and its impact on viable reuse ideas. The Alternate Uses Task (AUT) was used as a warm-up exercise versus its typical use as a creativity measure. This practical design application for the AUT resulted in a simple and easy to implement intervention that produced more correctly scaled reuses for the wind-turbine blade.
An Autobiographical Snapshot: The Impact of COVID-19 on Online Adult Learning in International Development
Keywords: Adult
Comparative Education
COVID-19
Higher Education
International Development
Online Learning

COVID-19 has shifted education moving from a primarily in-person model to a virtual one. Within the arena of International Development, higher education, particularly in Canada has had to adapt how they deliver workshops in an accessible way to participants in Egypt. My master’s study is a narrative inquiry told through the Five Contexts which is a framework developed by Dr Karyn Cooper and Dr Robert E White, these contexts include: Autobiographical, Political, Philosophical, Post-Modern and Historical (2012). The methodology adopted for this study is Hermeneutics which allows me to position myself and my interpretation of my experience within the context of the research (Laverty, 2003). The question being explored is how my experience can inform future programming as existing literature does not speak to the comparative education or project manager experience supporting international development programming. The thesis includes recommendations from my experience supporting a three-week Train the Trainers Pedagogy Workshop.