title: The role of CARM1 during skeletal muscle atrophy

title: CARM1 and muscle atrophy

contributor:
Ljubicic, Vladimir
Kinesiology

subject: CARM1 skeletal muscle atrophy

abstract: CARM1 and skeletal muscle atrophy

abstract: Coactivator-associated arginine methyltransferase 1 (CARM1) is emerging as an important player in skeletal muscle biology. We sought to elucidate the role of CARM1 in mediating muscle mass and function, as well as in the induction and progression of the muscle atrophy program. To this end, we engineered CARM1 skeletal muscle-specific knockout (mKO) mice and employed distinct, but complementary models of muscle atrophy, including neurogenic muscle disuse, food deprivation, and the sarcopenia of aging. CARM1 mKO resulted in reduced muscle mass and myofiber cross-sectional area concomitant with dysregulated autophagic and atrophic signaling, which indicates the requirement of CARM1 for the maintenance of muscle biology. Interestingly, CARM1 deletion mitigated the progression of both denervation- and fasting-induced skeletal muscle atrophy as compared to wild-type (WT) mice. Key mechanistic findings revealed that CARM1 interacts with the master neuromuscular regulator AMPK and attenuates the expression and activity of its downstream autophagy and atrophy networks. Surprisingly, both male and female mKO mice have a significantly shorter lifespan versus their WT littermates, revealed by a ~50% reduction in survival at 22-months-old, which is equivalent to ~70 years-old in humans. As such, we observed significantly reduced functional outcomes of integrative physiology in old mKO mice compared to old WT animals, such as strength and motor performance. Taken together, these results indicate that skeletal muscle CARM1 is indispensable for maintaining muscle mass, function, and lifespan. Targeting the interplay between CARM1 and AMPK may offer a viable therapeutic strategy for combating life-limiting muscle wasting conditions.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: While muscle wasting and weakness remains a widespread issue, the mechanisms that control muscle atrophy are not entirely understood. Previous evidence suggests that coactivator-associated arginine methyltransferase 1 (CARM1) regulates skeletal muscle remodeling. However, the role of CARM1 during muscle atrophy is unknown. Therefore, the purpose of this work was to investigate the function of CARM1 during muscle wasting. We generated mice with CARM1 deleted in skeletal muscle and studied the impact of CARM1 deficiency on the loss of skeletal muscle mass during muscle disuse, food deprivation, and aging. We found that CARM1 is required to maintain muscle mass under basal conditions. Interestingly, knocking out CARM1 in muscle attenuated the progression of denervation- and fasting-induced atrophy. However, CARM1 deletion in muscle resulted in lower muscle strength and a reduced lifespan. CARM1 deficiency did not prevent aging-induced muscle loss. Overall, these findings advance our understanding of CARM1 in skeletal muscle biology.


title: Corrosion Performance of High Temperature Alloys in Molten Salt Mixtures for Next Generation Energy Systems

contributor:
Kish, Joseph
Materials Science and Engineering

subject: Corrosion, molten salt, pre-oxidation, chemical purification

abstract:
Molten chloride salts have been proposed to be used as the primary coolant in molten salt reactors, and as the heat transfer fluid in concentrated solar power plants in next generation energy system design. The corrosive properties of molten chloride salts make it challenging to find appropriate structural materials for plant/system realization. In this work, two corrosion mitigation strategies are investigated to determine the relative corrosion performance of high temperature alloys in molten chloride salt mixtures: (1) chemical purification of salt mixture using a Mg sacrificial anode and (2) developing a protective oxide layer on the surface of high temperature alloys after pre-oxidation. These corrosion inhibitors are studied in combination with each other to determine the relative corrosion performance of three high temperature alloys: Incoloy 800H (chromia former), Haynes 214 (alumina former), and Noram SX (silica former). The unprotected and pre-oxidized alloys were exposed to molten chloride salt (62.5 wt % KCl + 37.5 wt % MgCl2·6H2O) with and without 1.7 wt % Mg as a corrosion inhibitor for 100 h at 700 °C under inert Ar atmosphere. SEM-EDS characterization was used to compare cross-sections and surfaces of each alloy exposed to molten salt with and without Mg additions. SEM-EDS cross-sectional characterization revealed significant Cr depletion in each
unprotected alloy, and reduced Cr depletion in alloys immersed in molten chloride salt mixtures with chemical purification included. The addition of Mg metal to the salt mixture resulted in the precipitation of MgO on the alloy surfaces. The oxide deposition of MgO on components may impact the thermal and mechanical performance of the system. Therefore, the addition of Mg should be optimized for use in an operational system. Cross-sectional analysis identified the dissolution of Cr2O3 and SiO2 oxide scales and a stable Al2O3 oxide scale post-exposure.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Influence of Fine-scale Niobium Carbonitride Precipitates on Hydrogen-Induced Cracking of X70 Pipeline Steel

contributor:
Kish, Joey
McDermid, Joseph
Materials Science and Engineering

subject:
Corrosion resistance
Hydrogen-induced cracking (HIC)
High strength low alloy (HSLA)
Nb content

abstract: The microstructure of steel is well known to affect hydrogen-induced cracking (HIC) susceptibility by having certain heterogeneities serving as effective hydrogen trap sites. A consensus on whether or not fine-scale niobium carbide (NbC), nitride (NbN) and carbonitride (Nb(C,N)) precipitates can behave as effective hydrogen traps has yet to be established. The H-trapping capacity of Nb precipitates in a Fe-C-Mn-Nb model steel was investigated with the goal of minimizing embrittlement effects and improving the design of X70 pipeline grade steel for sour service oil and gas applications. First, a heat treatment was applied to the model steel to change the Nb-based precipitate size distribution, which was subsequently characterized via transmission electron microscopy, electron energy loss spectroscopy, and atom probe tomography. The experimental heat treatment increased the number of fine-scale precipitates (<15 nm) that are ideal for APT characterization. NbN and NbC precipitates of various stoichiometries were confirmed within the steel. Further, a custom electrolytic H-charging device was designed, fabricated, and validated using thermal desorption spectroscopy. Additionally, the extent of galvanic corrosion between NbC and NbN and the steel matrix was determined using custom scaled-up particle matrix specimens. Potentiodynamic polarizations conducted using active and passivating electrolytes revealed the relative nobility of the materials. Both NbC and NbN particles were more noble than the steel matrix; thus, possessing driving force for galvanic corrosion, with the particles serving as cathodes. Future studies involving electrolytic charging of the steel in a D-based electrolyte coupled with atom probe tomography will facilitate the direct observation of H-trapping sites relative to various Nb-based precipitates and contribute to an improved understanding of the mechanisms governing HIC.

abstract: Thesis

abstract: Master of Science in Materials Science and Engineering (MSMSE)


title: Reliable High-Speed Short-Range Underwater Wireless Optical Communication Systems

contributor:
Hranilovic, Steve
Electrical and Computer Engineering

abstract:
In recent years, the high demand for high-speed communications at short-range
applications motivates underwater wireless optical communication (UWOC) systems
to be an alternative technology rather than acoustic and radio frequency (RF) technologies. However, UWOC systems require alignment, which is challenging underwater due to currents and waves of seawaters in addition to the system mobility.
The speed of UWOC links is restricted in practice due to the narrow bandwidth of
opto-electronic components and scattering in seawaters. In addition, the transmitted
optical power is restricted by noise and limited transmitted power due to eye-safety
standards. In order to tackle these challenges and provide reliable high-speed links,
this thesis proposes three new UWOC approaches which are appropriate for point-to-point and broadcast communications.
We propose angular multiple-input multiple-output (A-MIMO) and tracking AMIMO (TA-MIMO) communication systems for point-to-point links. In the first
part of this thesis, A-MIMO systems are proposed and modeled rather than conventional MIMO (C-MIMO) systems. Unlike C-MIMO systems, A-MIMO systems send
information in angle rather than in space, thus relaxing the strict requirements of on axis alignment and fixed channel length are relaxed. The main features of A-MIMO systems are highlighted, and maximum link lengths and angle-of-arrival (AoA) distributions are derived. C-MIMO and A-MIMO systems are simulated using a Monte
Carlo numerical ray tracing (MCNRT) method. Numerical results indicate that AMIMO systems are more robust than C-MIMO systems. As well, A-MIMO systems
can be implemented with smaller sizes.
In the second part of this thesis, motivated by the performance of A-MIMO systems, we introduce TA-MIMO systems. TA-MIMO systems inherit tracking advantages from their optical structures by which they infer the relative displacement and
tilt between ends of the link. Compared to A-MIMO systems, TA-MIMO systems
further enhance the link against tilt misalignment, and they perform localization functions besides communication. The architecture of TA-MIMO systems is described by
highlighting their inherent tracking advantages. Comprehensive analytic models for
TA-MIMO and A-MIMO links are derived by considering link misalignment, channel
impairments, and receiver noise. Closed-form expressions for AoA distributions are
derived and verified using a MCNRT method. Utilizing the architecture of TA-MIMO
systems, a pointing, localization, and tracking (PLT) scheme is proposed and modeled. Numerical results indicate that TA-MIMO systems outperform A-MIMO and
C-MIMO systems when the misalignment is presented by both displacement and tilt.
The third part of this thesis proposes a novel sea ice diffusing optical communication (SDOC) system for reliable broad-band broadcast communications under sea
ice, such as in the Arctic and Antarctic zones. SDOC systems utilize the sea ice
sheets floating on the sea surface to diffuse optical beams with wide spots and omnidirectional patterns from the transmitter to receivers. SDOC channels are modeled as
seawater-sea ice cascaded layers (SSCL) in which the vertical channel is divided into multiple layers based on their optical characteristics. An efficient methodology is proposed to compute channel impulse responses (CIRs), ensuring accuracy and reducing
computing time. In order to overcome the limitations of channel and receiver noise,
we propose a system architecture that enhances system speeds and ranges. Numerical
results reveal that, under a snow-covered sea ice sheet with a thickness of 36 cm, the
proposed system can achieve a communication speed of 100 Mbps with ranges up
to 3.5 meters with BER less than 10−3 and average transmitted power of 100 mW.
This work serves as a design guide to broadband-broadcast communications under
the frozen oceans. For example, a group of mobile sensors navigating below sea ice
sheets in Arctic regions could use SDCOC systems for real-time signaling exchange.

abstract: Thesis

abstract: Doctor of Engineering (DEng)

abstract:
Compared to acoustic and radio frequency systems, underwater wireless optical
communication (UWOC) systems utilize the broad bandwidth available to realize
high-speed links. Moreover, UWOC systems can be implemented with a small size and
work with low transmitted power. However, UWOC links require alignment between
the ends of the communication link, which is challenging due to seawater currents
and waves and system mobility. In addition, the speed and range of UWOC links are
restricted in practice due to the narrow bandwidth of opto-electronic components,
eye safety, and seawater scattering.
To realize reliable high-speed links, in the first part of this thesis, we propose
an angular imaging multiple-input multiple-output (A-MIMO) system by which the
alignment restriction is relaxed, and the link speed is raised in some scenarios. In
contrast to classic imaging MIMO systems, A-MIMO systems are robust against the
displacement and link length variations, thanks to sending beams in angle rather than
in space. A-MIMO systems are good candidates for mobile-to-fixed communications
where the relative displacement dominates the misalignment conditions.
For further enhancement in link reliability and speed, in the second part of this
thesis, tracking A-MIMO (TA-MIMO) systems are proposed. TA-MIMO systems inherit tracking features from their optical architecture and infer the relative position and orientation between the ends of links. TA-MIMO systems are promising
candidates in buoyed-to-fixed communications where the relative tilt dominates the
displacement conditions. In addition to communication applications, TA-MIMO systems offer localization features that are challenging to be realized underwater.
The third part of this thesis proposes a novel sea ice diffusing optical communication (SDOC) system for reliable broadband-broadcast communications under sea ice,
e.g., in Arctic and Antarctic zones. SDOC approaches utilize the sea ice sheet that
exists above seawaters to diffuse the optical beam omni-directionally from the transmitter to receivers. SDOC systems are promising solutions for real-time signaling
exchange between mobile sensors that navigate underneath sea ice sheets.


title: Hyaluronic Acid Based Therapeutic Bandage Contact Lenses For Corneal Wound Healing

contributor:
Sheardown, Heather
Chemical Engineering

subject: Therapeutic Bandage Contact Lenses

abstract:
The cornea is an avascular transparent tissue exposed to the environment and therefore highly susceptible to damage. With an increase in corneal refractive surgeries, corneal transplants, and corneal injuries, understanding and improving corneal healing mechanisms are extremely important. Impaired healing of corneal wounds can lead to decreased visual acuity and extreme pain. Serum eye drops, amniotic membranes, pharmaceutical agents, biopolymers, and cell transplants are just a few approaches that have been employed to improve wound healing. Bandage contact lenses (BCLs) have been proposed as a simple method to facilitate wound healing while reducing pain. The synthesis of a silicone hydrogel contact lens capable of surface binding hyaluronic acid (HA) for corneal wound healing was explored in the current work. HA was used as both a wetting agent and a therapeutic.
	The work presented describes the synthesis, characterization, and cell testing of the HA binding model silicone hydrogels, composed of the hydrophilic monomer, 2-hydroxyethyl methacrylate (HEMA) and a hydrophobic silicone monomer, methacryloxypropyltris (trimethylsiloxy) silane (TRIS). Three different methods were evaluated for increasing HA binding and improving surface wettability.
	“Caged lenses” utilized the same base polymer with the incorporation of methacrylated N-Hydroxysuccinimide (NHS). Hydrophilic polyethylene glycol (PEG) chains were then tethered from the NHS, forming a “cage” with the potential to physically entrap HA. Although surface wettability was improved, less HA was entrapped in the caged lenses compared to model silicone hydrogels, presumably due to the increased hinderance resulting from the PEG chains.
“Tethered HA” lenses utilized PEG as a spacer to conjugate HA to the lens surface in order to improve surface hydrophilicity. Methacrylated HA conjugation resulted in a significant decrease in contact angle (p <0.01) compared to model pHEMA-co-TRIS whereas tethered thiolated HA did not lead to a significant decrease (p >0.05) in contact angle. It was clear that neither of these methods would lead to sufficient HA binding.
Ionic interaction lenses utilize monomers and small molecules that contain a positive charge to bind to the negatively charged HA under physiological conditions. The monomer diethylaminoethyl methacrylate (DEAEM) was polymerized directly into the polymer backbone, but resulted in no significant decrease (p >0.05) in contact angle. In comparison, surface functionalization using thiolene “click” chemistry allowed conjugation of the small molecule, dimethylamino ethanethiol (DMAET) and diethylamino ethanethiol (DEAET).  DMAET and DEAET modified lenses showed significantly higher (p <0.001) HA binding compared to model pHEMA-co-TRIS controls at all time points. The modified lenses improved release kinetics preventing an initial burst release and showed consistent release when unloaded and reloaded with HA. The contact angle was significantly decreased (p <0.05) for the modified lenses with HA without affecting the equilibrium water content. Optical transparency was reduced following lens modifications although the thickness of the disks prepared was higher than a typical contact lens. Finally, the modified lenses did not exhibit any cytotoxicity in vitro with human corneal epithelial cells (HCECs).
The synthesis of silicone hydrogels capable of surface binding HA have potential to be used as a bandage contact lens while improving surface wettability and enhancing comfort.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Study of sorption properties of Eu on MX-80 bentonite under highly saline, reducing conditions， and under saline, reducing conditions

contributor:
Nagasaki, Shinya
Engineering Physics

subject:
MX-80
Eu
bentonite
Europium
surface complexation
sorption
reducing condition
saline
highly saline
PHREEQC

abstract:
Pu (III) is one of the key elements in the safety assessments of Canadian deep geological repository program (DGR). Sorption is a potential mechanism for retarding radionuclide transport from a DGR to the environment. In the current scenario, Pu (III) is considered to be a dominant radioactive element in the deep geological groundwater. Eu, considered to be a chemical analogue of Pu (III), its sorption behavior is now the target of our research.
This thesis investigates the sorption properties of Eu on MX-80 under saline reducing conditions, and highly saline reducing conditions. The thermodynamic sorption modelling of Eu is also need to be applied. A surface sorption model is also developed by applying computer program for Eu (III) on MX-80 to investigate the sorption mechanisms of Eu (III) sorption.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: A Framework for Comprehensive and Customizable Memory-Centric Workloads

contributor:
Hassan, Mohamed
Electrical and Computer Engineering

abstract:
Modern computer applications process massive volumes of data from sensors and cameras, putting tremendous demands on the system's memory bandwidth, energy, and predictability. Because main memory is the main bottleneck in such computing systems, researchers have proposed a number of novel memory solutions. However, because memory-centric benchmarks have been slow to emerge, these solutions are assessed using CPU-centric benchmarks or high-level memory access patterns benchmarks such as sequential vs random or read vs write. As a result, we present RAMify, a user-friendly and highly flexible framework for creating memory-centric architecture-aware workloads.

In this thesis, RAMify is presented, and its architecture, key features, and how to use it to formulate new performance benchmarks for evaluating memory subsystems are discussed. I also discuss how to update the framework for software development, and highlight the need for memory-centric benchmarks as well as the importance of RAMify in evaluating memory systems in modern computing platforms. We generate 132 workloads from RAMify to compare them with SPEC-CPU2006 and MemBen workloads. Furthermore, we utilized these workloads to perform a comparative study between the High Bandwidth memory (HBM) and Double Data Rate generation 4 (DDR4). Finally, we investigate HBM through the perspective of real-time systems, focusing on the HBM device to capture architectural factors that influence timing predictability, such as device access behaviour, timing characteristics, and performance measures.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Concentration and dynamics of two early fly embryo morphogens, Bicoid and Capicua, explored by FCS

contributor:
Cecile Fradin
Physics and Astronomy

subject:
Morphogen
Transcription factor
Concentration
Dynamics

abstract: PhD Thesis

abstract:
Morphogens (often acting as transcription activators or repressors) govern pattern formation and cell differentiation during early embryogenesis. Abnormal distributions of morphogens can result in developmental defects or even death. Oftentimes, thresholds of concentrations of morphogens behave like an ON/OFF switch for the activation or repression of downstream genes. Accurate measurements of morphogen concentration and mobility in space and time can help tackle the puzzle of how exactly cascades of hundreds of morphogens coordinate their targets precisely and promptly amidst crowded and complicated cellular environments. The research question at the centre of my thesis is that of the concentration and dynamics of two morphogens with opposite functions in the early fly embryo.
In the work presented in this thesis, we use Fluorescence Correlation Spectroscopy (FCS) and confocal imaging to achieve extremely low ($\sim$ nM) concentration measurements in live \textit{Drosophila} embryos expressing recombinant fluorescent morphogens, by carefully taking into account background noise and photobleaching effects. The dynamics of both Bicoid (Bcd) and Capicua (Cic), an activator and a repressor morphogens, were further studied using FCS, Fluorescence Recovery After Photobleaching (FRAP) and Monte Carlo simulation. We found that both types of morphogens are very mobile in nuclei, explaining how they are able to turn on or off gene expression in only a few minutes. However, these two morphogens with opposite functions have drastically different nucleo-cytoplasmic transport behaviours, where the activator can pass through the nuclear envelop (NE) relatively freely while the repressor is jailed inside nuclei during interphase. These findings can provide clues to distinguish between several hypothetical models (including the newly proposed hub hypothesis) trying to explain the mechanisms of target gene search and transcription regulation.

In this thesis, a background introduction on transcription factors and morphogens is given in Chapter 1, with a focus on the two transcription factors (the activator Bicoid and the repressor Capicua) studied in this thesis. Next, experimental details such as fruit fly maintenance, and fluorescent techniques used to measure concentration and mobility are described in Chapter 2. From Chapter 3 to Chapter 5, three manuscripts from the thesis author, either published or in preparation for submission are presented in sequence. Chapter 3 introduces a new method to accurately measure protein concentration in the presence of noise and photobleahing in early \textit{Drosophila} embryos using FCS. Chapter 4 contains the results of concentration and mobility measurements for Cic which contribute to the finding that Cic acts like a fast brake in transcription repression. Chapter 5 compares the similarities and differences of the dynamics of Bcd and Cic through multiple lenses. Finally, a conclusion and future outlook are given in Chapter 6.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Have you ever wondered how a single fertilized egg turns miraculouly into a beautifully organized living being, be it an insect, a cat, or a human?  It turns out that an important group of molecules called morphogens govern the formation of body pattern. These molecules (usually proteins) form concentration gradients along the different body axes of that organism and influence gene expression. Abnormal distribution of morphogen can result in defects in embryo development and even death. Thus knowing how much morphogen is present in the early developing embryo, as well as how it forms gradients and how the morphogen concentration is translated into a pattern can help us better understand early embryo development. My thesis focuses on accurate measurements of morphogen concentrations and dynamics using fluorescence techniques. We were able to obtain concentration maps for two morphogens, the activator Bicoid  and the repressor Capicua, in early developing fruit fly embryos. We also found that despite having opposite functions, the activator and the repressor have similar intranuclear dynamics, but drastically different internuclear mobility. Our findings provide clues to distinguish between multiple hypothetical models scientists have put forward to explain the mechanisms of transcription regulation.


title: Underwater Optical Wireless Localization

contributor:
Steve, Hranilovic
Electrical and Computer Engineering

abstract:
With the development of underwater technology, a more significant number of scholars and scientists have begun to pay attention to the development and application of UWOC (Underwater optical wireless communication) and UWONs (Underwater optical wireless networks). These studies require underwater localization technology to provide accurate location information. This thesis applies existing underwater positioning technology with knowledge of the LED Lambertian pattern with the aim of developing a low latency underwater positioning concept that helps locate the fast-moving underwater targets.

A key contribution of this thesis is the development of an adaptive time slot (ATS) approach.  Each buoy transmits signals in disjoint time slots which repeats periodically.  Given the random locations and orientations of the buoys, the distance from each buoy to the target will not be identical and will change in time.  These changes in position lead to overlap, discontinuity or loss of signals transmitted from buoys in each time slot.  The ATS approach uses the structure of these distortions received from multiple buoys to improve positioning accuracy.  The thesis provides comparison results with and without ATS in several practical scenarios.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Assessing the Relationships Between Onsite Wastewater Treatment System Microbial Communities, System Design, and Environmental Variables.

contributor:
Schellhorn, Herb
Biology

subject:
Bioinformatics
Anaerobic Digestion
Wastewater Treatment
Biostatistics

abstract: A Thesis Submitted to the School of Graduate Studies in Partial Fulfilment of the Requirements for the Degree of Master of Science.

abstract: Onsite wastewater treatment systems may be improved by altering the design and environmental variables that affect microbial community composition. However, the two most common methods of examining microbial composition through metagenomic sequencing (16S and shotgun sequencing) produce different taxonomic identification results according to microbial community composition and the analytical methods in use. To identify discrepancies between these two sequencing methods, we analyzed the effect of environmental and tank design variables on onsite-wastewater treatment system microbial communities sequenced using both 16S and shotgun sequencing. Shotgun and 16S sequencing produced different results when examining genera-level taxonomic richness, quantifying the effect of system design and environmental variables on community similarity, and identifying differentially abundant taxa between system types. Results were consistent when subjectively examining patterns of community similarity and when examining genera-level taxonomic diversity above 0.1% relative abundance. Identifying methods that produce similar results between 16S and shotgun sequencing supports the reliable analysis of and optimization of OWTS processes.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Onsite-wastewater treatments systems such as household septic tanks are vital tools for managing wastewater. However, the microbial ecosystem which digests waste within septic tanks contains unknown interactions that can alter the rate of waste digestion. We used two DNA sequencing methods to assess how microbial communities within septic tanks responded to the tank design and surrounding environment. We then compared results produced by the two sequencing methods. The response of microbial communities to tank design and the environment differed between the two methods. However, the two methods both indicated that one system design produced a more variable microbial community.


title: Tuning and Optimising Concept Drift Detection

contributor:
Chiang, Fei
Computing and Software

subject:
concept drift
anomaly detection
concept drift detection

abstract:
Data drifts naturally occur in data streams due to seasonality, change in data usage,
and the data generation process. Concepts modelled via the data streams will also
experience such drift. The problem of differentiating concept drift from anomalies
is important to identify normal vs abnormal behaviour. Existing techniques achieve
poor responsiveness and accuracy towards this differentiation task.
We take two approaches to address this problem. First, we extend an existing
sliding window algorithm to include multiple windows to model recently seen data
stream patterns, and define new parameters to compare the data streams. Second,
we study a set of optimisers and tune a Bi-LSTM model parameters to maximize
accuracy.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Machine Learning for Classification of Pediatric Concussion Recovery Stages

contributor:
Noseworthy, Michael
Biomedical Engineering

subject:
Machine Learning
Concussion
Pediatric

abstract:
Mild traumatic brain injury (mTBI), or concussion, results from sudden acceleration
or deceleration of the brain and subsequent complex tissue propagation of shock waves
that disrupt structure and function. Concussions can cause many symptoms including
headache, dizziness, and difficulty concentrating. These can be detrimental to children,
a ecting their participation in school, sport, and social activities. Therefore,
return to school (RTS) and return to activity (RTA) protocols have been developed to
help safely return children to these activities without risking further injury. The goal
of this study was to develop machine learning (ML) algorithms to predict RTA and
RTS stages, that can easily be incorporated into a smartphone application (APP).
Ideally this would assist children in tracking and determining their RTA and RTS
progression leading them to a safe and timely return.
Support vector machine classi er (SVC) and random forest (RF) algorithms were
developed to predict RTA/RTS stages. Both were modeled on previously acquired
data, and on newly acquired data, and results were compared. Models were trained
and tested using accelerometry and symptom data from pediatric concussion patients.
A sliding window technique and feature extraction were performed on raw acceleration
data to extract suitable features, which were combined with yes/no symptom
recordings as ML inputs. The dataset consisted of 67 participants aged 10 to 18, 42
female and 25 male, with a total of 844408 samples.
The best results for RTS prediction showed average accuracy of 83% for RF and
66% for SVC. For RTA predictions, the best results had average accuracy of 60% for
RF and 58% for SVC. For new data, RTS predictions showed an accuracy of 45%
for RF and 41% for SVC. RTA predictions had an accuracy of 35% for RF and 30%
for SVC. RF models had superior performance on all data. These results show that
predicting RTA/RTS is possible with ML. However, improvements to these models
can be made by training on more data prior to APP implementation. More data is
needed, as recruitment during this study was limited due to Covid-19 restrictions.

abstract: Thesis

abstract: Master of Applied Science (MASc)

abstract:
Concussions are recorded in approximately 300,000 athletes annually and are estimated
to a ect up to 3.8 million individuals per year in the United States alone.
Understanding when its safe to return to normal routine after an injury is important
but challenging. Therefore, a series of stages have been developed to lead children
through a safe and timely return to sport and activity after concussion. The goal
of this study was to develop machine learning (ML) algorithms which predict these
return stages using symptom recordings and gross body movement data. Algorithms
could be incorporated into a smartphone application (APP) to provide accessible return
guidelines for children with concussions. Algorithms were created and model
performance was tested using symptom and body movement data collected from children
after a concussive injury. The results of this study show that it is possible to
predict return to school and return to activity stages with ML, and with improvements,
can be used to facilitate return from injury


title: The Effects of Exposure to Trace Elements on the Skeletal Health of American Mink

contributor:
Quenneville, Cheryl
Biomedical Engineering

subject:
environmental toxicology
bone
bone health
biomechanics
mink
biomonitoring

abstract:
The release of pollutants by the oil sands industry and pulp and paper mills has been an ongoing environmental concern for decades. Such toxins have been linked to declining reproductive and skeletal health in wildlife species, as they have known endocrine disrupting properties that interfere with hormones responsible for proper reproduction and bone development. As such, declining population sizes because of pollutant exposure has been correlated with altered bone health in mammals. For the purposes of environmental monitoring, the development of a biomarker of pollutant exposure would be a beneficial tool to assess pollution impact on wildlife populations. Therefore, the purpose of this research was to identify this biomarker in the American mink based on measures of their bone health. Mink from the Athabasca Oil Sands Region and an area surrounding a pulp and paper mill in
Quebec were collected. From each mink, a hindlimb femur and the baculum (for males) were
dissected. Bones were evaluated through a series of tests to quantify key cortical and cancellous bone structural and material properties. These included dimensional analysis, three-point bending and micro-Computed Tomography. Toxicology reports of trace element exposure levels in the minks were also provided by ECCC. Principal component analyses and correlation matrices were used to identify potential relationships between the bone metrics and trace element levels, followed by linear regression modeling. Results found that the baculum and femur structural properties were correlated with selenium, rubidium and iron concentrations, suggesting that these elements had the strongest influences on bone health for the mink studied here. This work provides the basis for future research on identifying a biomarker determinant of bone health to be used in environmental monitoring effects programs. The results here indicate that baculum bone measures are dominated by trace element effects rather than loading effects and are thus a useful bone to investigate for biomonitoring programs. This will provide a simple and reliable method for determining whether there are unsustainable levels of pollution in regions across North America.

abstract: Thesis

abstract: Master of Applied Science (MASc)

abstract:
Environmental pollution in regions across Canada puts the health of communities and wildlife at risk. To better measure the impact of pollution in these regions, the implementation of a species monitoring program would benefit those communities who are at the greatest risk. Therefore, this research was aimed at developing an indicator of harmful pollution exposure in mink, an abundant species in Canada, by investigating their bone health. A group of mink from Alberta and Quebec were collected and their femur and penile bones tested for a variety of bone health measurements. In addition, information on the heavy metal levels in the mink livers were provided. The bone health measurements and heavy metal levels were then compared to look for any relationships between them. This research found that selenium, rubidium and iron had the strongest effects on bone health. The methods used have set the groundwork for using minks to monitor pollution levels across
North America.


title: Assessment of the sources and biodegradation potential of hydrocarbons and naphthenic acids in an oil sand end pit lake

contributor:
Slater, Greg
Earth and Environmental Sciences

abstract: Reclamation efforts have been ongoing to manage and reclaim the mined-out pits and the tailings produced from oil sands production. Syncrude has implemented the first end pit lake, known as Base Mine Lake (BML), by using water cap tailing technology (WCTT). The lake was constructed by capping 186 million m3 of fluid fine tailings (FFT) with a 65 million m3 water column from OSPW (oil sand process water) and Beaver Creek Reservoir (BCK) forming a total depth of 48m. The organic compounds present within the FFT, such as hydrocarbons and naphthenic acids (NAs), are residual organic matter from the bitumen after extraction or the diluent naphtha. Consumption of residual organic compounds through syntrophic fermentation coupled to methanogenesis in the FFT generates methane that can be transported upward to the water column through advection, diffusion or ebullition. The oxidation of the methane by methanotrophs depletes the oxygen concentration in the water column. An integral part of the success of the WCTT is the demonstration of stable oxygen conditions in the water column that would facilitate the biodegradation of residual organic matter which can be transported into the water column from the FFT. This dissertation utilized multidimensional chromatography to assess the residual organic compounds in BML and evaluate their biodegradation potential. Assessment of the hydrocarbons in the FFT indicated that the low molecular weight compounds are being biodegraded at shallower intervals and potentially driving methane production. The analysis of NAs distribution in BML revealed that additional input of NAs into the water column, through biodegradation of hydrocarbons or advection from the FFT, is being balanced by ongoing microbial degradation in the water column. Evaluation of the biodegraded metabolites revealed that hydrocarbons are anaerobically degraded in the FFT while NAs are aerobically degraded in the water column of BML. This study demonstrates that studying the molecular fingerprint distribution of residual organic compounds using multidimensional chromatography indicated that biodegradation is managing the release of compounds of concern, and could help assess the success of reclamation and obtaining certification.

abstract: Thesis

abstract: Doctor of Science  (PhD)


title: Post-Polymerization Click Functionalization of Conjugated Polymers

contributor:
Adronov, Alex
Chemistry and Chemical Biology

subject:
Conjugated Polymers
SPAAC
IEDDA
Click Chemistry
Polymers
Host-Guest Chemistry
Organogels
Post-Polymerization Functionalization

abstract: The thesis work described herein explores two avenues of post-functionalization of conjugated polymers using ‘click’ chemistry. The first avenue utilizes the Strain-Promoted Alkyne-Azide Cycloaddition (SPAAC) and the second an Inverse Electron-Demand Diels-Alder (IEDDA). In the first part of this thesis, various azide moieties were SPAAC ‘clicked’ onto a dibenzocyclooctyne-containing polymer, such as small molecules like para-phenyl-nitroazide, as well as larger azide-terminated chains like polystyrene and polyethylene glycol.  Host-guest chemistry and self-healing organogels were also explored. The synthesis of each component, including the cyclooctyne diamine monomer, dialdehyde comonomer, resulting polymer, various azide moieties, as well as the SPAAC click reactions, are all described in detail along with extensive characterization. Similarly, the second part of this thesis involved the synthesis and characterization of several components, including the tetrazine monomer, fluorene comonomer, resulting polymer, and various TCO derivatives for the post-polymerization IEDDA ‘click’ reactions onto the backbone. Some of the click reactions described include small molecule TCO derivatives, polymeric PEG TCO, and a difunctional linker to generate a crosslinked foam.

abstract:
Conjugated polymers attract significant attention due to their interesting optoelectronic and physical properties. Over the past few decades, tremendous effort has been devoted to expanding the structural diversity and applications of this class of macromolecules. The pursuit of structural variability of conjugated polymers has resulted in a broad range of research to understand their structure-property relationships via functionalization. This functionalization is crucial for tailoring performance in any given application. Thus, the ability to synthesize a library of homologous polymers would prove very useful. Efficiency is of utmost importance when creating a library of homologous conjugated polymers, as the faster a library can by synthesized, the sooner said polymers can be screened for any desirable properties. Such an approach requires a post-polymerization functionalization strategy, whereby a progenitor polymer undergoes efficient reactions at each repeat unit of the backbone.
The work presented in this thesis involves synthesizing a reactive conjugated polymer scaffold, followed by efficiently post-polymerization functionalization via “click” chemistry. Two elegant click reactions are described in this work; the Strain-Promoted Alkyne-Azide Cycloaddition (SPAAC) and Inverse Electron-Demand Diels-Alder (IEDDA). The SPAAC reaction allowed for rapid functionalization of triazole moieties on a dibenzocyclooctyne-containing polymer backbone, creating a small polymer library with a consistent degree of polymerization (DP). Grafting with polystyrene and polyethylene glycol azide-terminated polymers allowed the efficient syntheses of a series of graft-co-polymers with Mn values up to 800 kDa and varying solubilities. Secondly, The IEDDA reaction was applied to a poly(tetrazine-co-fluorene) conjugated polymer, which resulted in the rapid and quantitative functionalization of the polymer backbone with trans-cyclooctene derivatives. These reactive conjugated polymers were explored in a variety of applications, including supramolecular chemistry and gel formation.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract:
Conjugated polymers are a class of macromolecular materials that attract significant attention due to their interesting behaviors and properties. Under certain conditions, these polymers even display conductivities like that of metals. As such, they show promise in applications such as organic solar cells, chemical sensors, organic light-emitting diodes, and supercapacitors. Over the past few decades, tremendous effort has been devoted to expanding on the types of conjugated polymers as well as their structural diversity. This, of course, has resulted in polymers that exhibit vastly different behaviours depending on what they are made of. As certain applications (e.g.: solar cells) require polymers with very specific properties, being able to ‘tune’ a conjugated polymer to ‘match’ a required property would be extremely useful. This tuning of polymer properties can be successfully accomplished by attaching different structures onto the polymer chain by utilizing a reaction known as ‘post-polymerization functionalization’. In doing so, a starting reactive polymer can be transformed into an entirely different polymer with specific chemical properties and behaviors.
The work presented in this thesis involves synthesizing two types of conjugated polymers and attaching various structures onto their backbones to yield different properties. The synthesis, characterization, and potential applications of said polymers are described herein.


title: Cognitive Ecology: Animal Movement and Collective Decision-Making

contributor:
Dukas, Reuven
Psychology

subject:
decision-making
collective intelligence
movement ecology
cognition
expertise
navigation

abstract: Cognition shapes how we perceive and react to our environment. Throughout my Master of Science, I have studied two major fields of animal cognition. My thesis first reports on the cognitive aspects of animal navigation in home ranging and seasonal migration, then I explore the development of group expertise through extensive experience with collective decision-making. The key contributions of the first manuscript (Chapter 2) are a condensed yet detailed summary of the behaviours involved in individual and collective animal movement, followed by research ideas to fill the gaps of the current literature. The key contribution of the second manuscript (Chapter 3) is developing an experiment to study group expertise, a topic that currently lacks controlled experiments, via testing the effect of experience on collective decision-making. This thesis expands the existing knowledge on animal movement and collective decision-making.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Cognition is the process of attaining, processing, and using information. Perception, learning, and memory are the main cognitive processes that are responsible for how we understand the world around us. In my thesis, I first review the cognitive processes involved in short-distance and long-distance animal movements. Secondly, I examine how a specific type of cognition, collective decision-making, improves with experience. Together, I reflect on various pillars of animal cognition, discuss my contributions to the field, and suggest further research ideas.


title: Investigation of Candidate Reference Genes for Reverse-transcription Quantitative Polymerase Chain Reaction of Aspergillus

contributor:
Xu, Jianping
Biology

subject:
Aspergillus
Reference Genes
RT-qPCR
Triazole

abstract: The genus Aspergillus possesses broad functionality and occupation of ecological niches. Underpinning this are changes in the transcriptome of these species. Transcriptional changes are clinically relevant with respect to understanding triazole resistant isolates of Aspergillus fumigatus. Reverse-transcription quantitative Polymerase Chain Reaction (RT-qPCR) is a highly specific means of measuring changes in gene expression. The most common method of which requires normalization to experimentally validated, stably expressed reference genes. Ideal reference genes are unaffected by differences in the experimental conditions or strains/isolates and are expressed at levels near the target gene(s). The first study reviewed current practices for reference gene selection and validation for RT-qPCR gene expression analysis of the genus, Aspergillus. Information on the species examined, experimental conditions, sample type, normalization strategy, reference gene(s) and their state of validation was obtained from 90 primary studies. Twenty reference genes were used, with the most popular reference genes used encoding beta-tubulin, actin, 18S rRNA and glyceraldehyde-3-phosphate dehydrogenase. Seventeen of the 90 studies experimentally validated the expression stability of the reference genes used, out of which eight used more than one reference gene. The results of three studies conflicted with others described in the literature, with no experimental validation of the reference genes available to aid in interpreting the conflicting findings. In the Genome-Wide Association Study, genes noted to increase in expression in response to itraconazole and/or voriconazole treatment of A. fumigatus were extracted from published RNA-sequencing or RT-qPCR studies. Ten ATP-binding cassette transporters, four major facilitator superfamily transporters and 16 transcription factors were identified. Collectively, the findings of this thesis show a large disparity in experimentally validated reference genes as well as future targets of gene expression analysis in triazole resistant isolates of A. fumigatus.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Aspergillus is a globally distributed genus of fungi, with some species threatening opportunistic human infection. To combat infection with the opportunistic species, Aspergillus fumigatus, antifungal drugs including: itraconazole, voriconazole and amphotericin B are used. Recent years have seen a rise in antifungal resistance in A. fumigatus. To understand this and other mechanisms in Aspergillus, changes in gene expression must be examined. My thesis aimed to determine how reference genes are selected for reverse-transcription quantitative polymerase chain reaction, a method applied to measure gene expression changes in Aspergillus. It was discovered that very few studies between the years 2001 and 2020 experimentally validated that the reference genes used were stably expressed, with only 17 out of 90 studies providing validation. In part two of my thesis, genes overexpressed in A. fumigatus when exposed to antifungal drugs, from formerly published articles, were summarized to better understand the role of gene expression in antifungal drug resistance.


title: Discrete Geometry and Optimization Approaches for Lattice Polytopes

contributor:
Deza, Antoine
Computing and Software

subject: polytopes lattices diameter optimization

abstract:
Linear optimization aims at maximizing, or minimizing, a linear objective function
over a feasible region defined by a finite number of linear constrains. For
several well-studied problems such as maxcut, all the vertices of the feasible region
are integral, that is, with integer-valued coordinates. The diameter of the
feasible region is the diameter of the edge-graph formed by the vertices and the
edges of the feasible region. This diameter is a lower bound for the worst-case
behaviour for the widely used pivot-based simplex methods to solve linear optimization
instances. A lattice (d,k)-polytope is the convex hull of a set of points
whose coordinates are integer ranging from 0 to k. This dissertation provides new
insights into the determination of the largest possible diameter δ(d,k) over all
possible lattice (d,k)-polytopes. An enhanced algorithm to determine δ(d,k) is
introduced to compute previously intractable instances. The key improvements
are achieved by introducing a novel branching that exploits convexity and combinatorial
properties, and by using a linear optimization formulation to significantly
reduce the search space. In particular we determine the value for δ(3,7).

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Identification of Core Allosteric Networks and Development of QSAR Models for EPAC1

contributor:
Melacini, Giuseppe
Chemistry and Chemical Biology

abstract: Allosteric regulation is essential to control biological function. In addition, allosteric sites offer a promising venue for selective drug targeting. However, accurate mapping of allosteric sites remains challenging since allostery relies on often subtle, yet functionally relevant, structural, and dynamical changes. In this thesis, a new toolset of NMR-based methodologies known as T-CHESCA and CLASS-CHESCA are proposed to identify key allosteric sites, using isoform 1 of the exchange protein activated by cAMP (EPAC1) as the model system. The T-CHESCA imposes changes on the fast-exchanging active/inactive states of the protein through temperature changes while the CLASS-CHESCA imposes changes through variations in the spin-active nuclei involved in pairwise correlations of residues. The residue ensembles identified by the CHESCA methods were found in previously identified EPAC allosteric sites. EPAC1 has also been identified as a promising drug target for cardiovascular diseases and based on structural analogues of a novel EPAC1-specific inhibitor called I942, the next aim of the work was to generate a quantitative structure activity relationship model (QSAR). The QSAR model was able to predict the affinity of a promising inhibitor with enhanced potency and inhibitory activity compared to I942 which was confirmed through competition assays, 15N-1H HSQC experiments, saturation transfer difference (STD) and chemical shift projection analysis (CHESPA).

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Exchange proteins activated by cyclic AMP (EPAC) are cAMP sensors with several functions in cellular pathways. EPAC has been found to be associated with multiple diseases such as cardiovascular diseases. This study aims to first identify the main residues involved in the regulation of EPAC1 activity and then develop a predictive model that is able to find promising and selective inhibitors for the protein. The two approaches can then be useful in designing effective modulators of EPAC1 for the treatment of cardiovascular diseases such as cardiac hypertrophy.


title: Ginzburg-Landau theory of complex spherical packing phases in soft condensed matter

contributor:
Shi, An-Chang
Physics and Astronomy

subject: soft condensed matter physics

abstract:
Stable Frank-Kasper spherical packing phases have been observed in a wide variety of soft-condensed matter systems, but the universality of these phases is not well understood. Recently, it was shown that the Frank-Kasper $\sigma$ and A15 phases are stable in the well-known Landau-Brazovskii (LB) model. In this work we consider the $\sigma$ and A15 phases, as well as the Laves C14 and C15 phases, and show that none of these is stable in the Ohta-Kawasaki (OK) model, which is another widely studied Ginzburg-Landau theory.  The LB and OK models differ only in their quadratic coefficients. We conduct a thorough investigation of the role that this coefficient plays in stabilizing the complex phases.  We uncover generic principles linking the functional form of the coefficient in reciprocal space with the stability of the complex phases.  A Ginzburg-Landau theory for a
for diblock copolymer system with a conformational asymmetry parameter is derived, but the complex phases are not found to be stable in this model.  We also consider a Ginzburg-Landau theory for a system of hard spheres interacting via a pairwise short-range attractive, long-range repulsive (SALR) potential, and use our framework to demonstrate how the parameters in the potential influence the stability of the Frank-Kasper phases. Taken together, these results provide insight into the universal mechanisms that underlie the formation of the complex spherical packing phases in soft condensed matter.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Soft condensed matter physics is the study of soft, deformable materials, such as soap bubbles, foams, and plastics.  Many different soft matter systems undergo a fascinating phenomenon known as self-assembly, wherein the constituent particles spontaneously arrange themselves to form various ordered structures.  In particular, the spherical packing phases appear when the particles first cluster into spherical aggregates, which then pack into larger arrangements. This sort of self-assembly is interesting because many different spherical arrangements are observed, including  the complex spherical packing phases (also known as the Frank-Kasper phases). The fact that these complex phases appear in many different types of materials is not well understood.  In this thesis we use a model known as the Ginzburg-Landau theory to ask which of these arrangements will form in a given system, and why. We uncover generic features of the Ginzburg-Landau theory that control which spherical packing phases appear, and we connect these features to several specific systems. These results provide insight into the mechanisms behind the formation of the complex spherical packing phases in a diverse range of systems.


title: A supercapacitor Based on Graphite Paper

contributor:
Xu, Gu
Materials Science and Engineering

abstract: As a new energy storage device, supercapacitor (SC) has attracted much attention because of its advantages like long service life, high power, and environmental protection. In the study of SCs, Polyaniline (PANI) has attracted great attention because of its high conductivity and good stability. But the working voltage of PANI based electrode is low (≤0.8V) as it usually gets crushed under higher voltage. Therefore, slowing down the crushing of PANI and increasing the working voltage of PANI based SC has been urged for the performance improvement of this kind of SC. Despite many previous attempts, the performance has not been significantly improved. In this research, the performance has been effectively improved by introducing MnO2 and quasi-solid electrolyte into electrode system, where Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and battery test system have been conducted. The specific capacitance was increased by 30% in 1000 cycle times and the working voltage was doubled. Meanwhile, the lead-in of graphite paper (GP) and quasi-solid electrolyte make SC flexible and thinner, which improve the wearability of devices.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Health Promotion and Childhood Obesity among Indigenous Children: Understanding Community Priorities, Prevention Programs, and Protective Factors

contributor:
Anand, Sonia
Health Research Methodology

abstract:
The global prevalence of childhood overweight and obesity has more than quadrupled in the last 40 years. Emerging evidence suggests that the propensity to develop non-communicable chronic diseases, including obesity, is rooted in early-life exposures. There are populations that have a more significant burden of childhood obesity and related complications, in Canada this includes Indigenous peoples.
The higher burden of obesity and non-communicable chronic diseases is explicitly rooted in the social determinants of health, and any discussion of the determinants of health for Indigenous peoples in Canada should be inclusive of historical and present-day contextual factors that have ongoing impacts on health outcomes including colonialism, racism, and self-determination.
With a guiding framework of community-based participatory research this thesis consists of two published manuscripts and one manuscript prepared for submission. The work is woven together by the theme of understanding community priorities, effectiveness of programs, and determinants for obesity prevention strategies among Indigenous children. The first study is a qualitative descriptive study in partnership with two First Nations communities in Canada. The objective of the study was to support two Indigenous communities in identifying priorities and strategies for promoting healthy nutrition and physical activity for young children. The second study is a systematic review which sought to describe the effectiveness of programs aimed at obesity prevention and/or the promotion of healthy lifestyle behaviours for Indigenous children. The last study examines how factors including social disadvantage, maternal education, maternal diet, and traditional birth practices are associated with infant diet at age 1-year. The final chapter describes the implications of the findings.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Frailty in a Global Population: Should Geographic Region Influence Frailty Definitions?

contributor:
Leong, Darryl
Health Research Methodology

subject: Frailty, Population and Public Health, Low- and Middle-income countries (LMICs)

abstract:
Introduction:
The frailty phenotype is a commonly used tool to study frailty. Two characteristics evaluated as part of the frailty phenotype are “low” grip strength and “low” physical activity, defined by the lowest quintile thresholds for age and sex. In studies of frailty in different geographic regions of the world, it is not established whether these thresholds should be applied universally or whether region-specific thresholds of grip strength and physical activity should be applied. This study aims to determine which way of defining frailty is more appropriate.
Methods:
Using data from the Prospective Urban Rural Epidemiology study, two variations of the frailty phenotype were defined: universal frailty in which thresholds for low grip strength and physical activity were taken to be the lowest quintile of the entire study population and region-specific frailty, in which these thresholds were calculated separately for each region. Frailty prevalence was calculated for each definition and Cox proportional hazards modelling was used to determine which definitions predicted mortality. Likelihood ratio tests statistics, area under the receiver operating characteristics curve, and the net reclassification improvement index were also calculated.
Results:
Overall frailty prevalence was 5.6% using universal definitions of frailty and 5.8% for region-specific definitions of frailty. Across regions, universal frailty prevalence ranged from 2.4% (North America/Europe) to 20.1% (Africa), while region-specific frailty ranged from 4.1% (Russia and Central Asia) to 8.8% (Middle East). The hazards ratios for all-cause mortality were 2.66 (95% CI: 2.47-2.86) and 2.09 (95% CI: 1.94-2.26) for universal frailty and region-specific frailty respectively (adjusted for age, sex, education, smoking status and alcohol consumption); statistical tests indicated that universal frailty better fit survival data and predicted mortality slightly better.
Conclusions:
Frailty prevalence varies greatly across regions depending on how the thresholds for low physical activity and grip strength are calculated. Using region-specific thresholds does not help improve the predictive value of frailty when measuring frailty in heterogenous populations using the frailty phenotype.

abstract: Thesis

abstract: Master of Science (MSc)


title: Inclusive Physical Education in Secondary School: An Exploration of Curriculum, Current Literature, and Teacher Perspectives

contributor:
Missiuna, Cheryl
Rehabilitation Science

subject:
Inclusion
PE
High School

abstract: Inclusive education involves the participation of all children, including those with disabilities, as an expectation within mainstream education. The goal of inclusive education in Ontario, Canada is for all students, regardless of differences, to have equitable access to curriculum instruction with their typically developing peers. Physical education (PE) involves curriculum delivery in unique settings. While inclusive practice in PE has been studied in elementary schools, less research has focused on secondary school. In this dissertation, I explore how curriculum, resources, and educational practices support or create barriers for provision of inclusive PE in secondary schools. The first manuscript describes a critical discourse analysis of the 2015 Ontario Physical Education Curriculum, Grades 9-12. Analysis considers how language is used and reflected within curricular text to represent inclusion. The analysis highlights that teachers require support beyond policy to practice inclusion, and advocates for teacher and student voices to be represented in curricular documents. The second manuscript presents a rapid review of current literature to overview resources for Universal Design for Learning (UDL) available to support implementation in PE settings. Findings show that literature available to encourage professional development in universal design in PE is limited but growing. Physical educators still require support to facilitate implementation of UDL in practice. The third manuscript uses interpretive description to explore the perspectives of Ontario secondary school PE teachers implementing inclusive PE. Physical educators express a need for professional development opportunities and in-situ resources that provide informed knowledge about inclusive practices. The discussion chapter reflects on the exploratory findings of this research. Collaboration with school-based rehabilitation health professionals, such as occupational therapists and physical therapists, may provide a novel approach to support physical educators. Future research, policy, and practice initiatives should consider teacher agency within the context of system-based barriers that exist and influence inclusive PE.

abstract: Thesis

abstract: Candidate in Philosophy

abstract: Inclusive classrooms allow children with different abilities to learn together. Physical education (PE) is a class that may require adaptive teaching strategies and environmental modifications for all students to participate. This thesis explores how we can support PE teachers in delivering inclusive PE for secondary school students. The first study looks at how the Ontario Secondary School PE curriculum uses language to support inclusion. The second study identifies recent literature that explores how Universal Design for Learning, as a teaching approach, is used in PE classes to support inclusion. The third study examines physical educators’ views on what they need to create inclusive classes so that diverse students can participate fully. Findings from all studies suggest that PE teachers may benefit from collaboration with health professionals with expertise in development, movement science, and inclusion.


title: How midwifery clients in Ontario access information to support infant feeding decisions: a cross-sectional survey

contributor:
Alvarez, Elizabeth
Health Research Methodology

subject: breastfeeding; infant feeding; information access; Ontario midwifery; midwife-client relationship; online information environment; infant feeding goals

abstract: The initiation and duration of exclusive chest/breastfeeding are important health determinants and a key focus of existing public health policy and programs. Despite the demonstrated benefits of chest/breastfeeding and focus on interventions, overall rates of initiation and exclusivity in Ontario remain low. The purpose of this study was to describe how midwifery clients in Ontario - a population credited with high rates of exclusive chest/breastfeeding - access information to support infant feeding decisions. A descriptive, cross-sectional online electronic survey was conducted using the Midwifery Infant Feeding Information Survey questionnaire which was locally developed for this study. A total of 235 midwifery clients who were either in or recently discharged from midwifery care at the time of the survey completed the questionnaire. Data analysis was completed using descriptive statistics with total counts and content analysis for open-ended questions. This research contributes new knowledge about infant feeding information access including the reported usefulness and preferences of various information sources across the continuum of care; the importance of the midwife-client relationship and the online information environment; potential communication gaps in the delivery of comprehensive prenatal infant feeding information; and self-reported infant feeding patterns suggesting midwifery exclusive chest/breastfeeding rates may not be as high as previously thought. Further research to improve information access is needed in order to identify barriers midwives face in discussing infant feeding with clients; explore the effect of health literacy in an online information environment to support the potential development of evidence-based, midwifery-specific online/digital tools. The study findings are relevant for both the academic and clinical midwifery community in developing effective strategies to further support midwifery clients in meeting their infant feeding goals. This study will further inform researchers, public health practitioners, policy makers, and other stakeholders representing all childbearing families in Ontario.

abstract: Thesis

abstract: Master of Public Health (MPH)

abstract: The goal of this study was to examine how midwifery clients in Ontario access information about infant feeding throughout the pregnancy and postpartum period. An online survey of 235 current and former midwifery clients identified why some information sources were more useful than others, and how infant feeding information could become more accessible. The midwife-client relationship and use of online/digital media were identified as important information sources. However, a number of information gaps were identified that suggest not all clients benefit from comprehensive discussions with their midwife in preparation for infant feeding. Further research is needed to understand barriers midwives may face in discussing infant feeding with their clients, and the use of online/digital tools to support midwifery clients to meet their infant feeding goals. The results of this study may benefit all childbearing families in Ontario.


title: Integrating Sap Flow and Eddy Covariance Techniques to Understand the Effects of Forest Management on Water Fluxes in a Temperate Red Pine Plantation Forest

title: Water dynamics in managed pine plantation forests

contributor:
Arain, M Altaf
Earth and Environmental Sciences

subject: forest management, water, climate change

abstract:
Forests provide important ecosystem services and play a dominant role in the global carbon and hydrologic cycles. These ecosystems are becoming more vulnerable to climate change-related threats such as extreme temperature and precipitation events, drought and wildfires. In addition, forest ecosystems have also undergone land use changes and a significant reduction in cover area, specifically in North America. There has been renewed realization to restore and rehabilitate forest ecosystems because they are a major carbon sink and play a key role in sequestering atmospheric carbon dioxide. In response, plantation forests are being widely established to sequester carbon, increase biodiversity, secure water resources and generate economic revenue when harvested. Forest managers employ different  management practices such as thinning or retention harvesting to enhance growth, plant structural and species diversity within forest plantations, with the ultimate goal of emulating the characteristics and benefits of natural forests. However, the influence of these forest management practices on the growth, productivity and specifically water cycling in plantation forests is not well studied and reported in the literature.
This experimental study investigated the effect of four different variable retention harvesting (VRH) treatments on evapotranspiration and water balance in an 83-year-old red pine (Pinus resinosa) plantation forest in the Great Lakes region in Canada. These VRH treatments included 55% aggregated crown retention (55A), 55% dispersed crown retention (55D), 33% aggregated crown retention (33A), 33% dispersed crown retention (33D) and unharvested control (CN) plot. Tree-level experimental work was conducted in the control plot and showed that most of the water transport (65%) occurred in the outermost sapwood, while only 26% and 9% of water was transported in the middle and innermost depths of sapwood, respectively. These results help to avoid overestimation of transpiration, which may cause large uncertainties in water budgets in pine forests. Study results further showed that the 55D treatment had the highest tree-level transpiration followed by 33D, 55A, 33A and CN plots. During periods of low precipitation, vapor pressure deficit (VPD) was the main driver or control on transpiration in VRH treatments. However, transpiration was more closely coupled with photosynthetically active radiation (PAR) in the control plot. Moreover, the 55D treatment resulted in on average 58% of total water loss from canopy as transpiration and 42% from the understory and ground surface as evapotranspiration. These findings suggest that dispersed or distributed retention of 55% basal area (55D) provides the optimal environmental conditions for forest growth with reduced competition of trees for water as shown by enhanced transpiration. This study will help researchers, forest managers and decision-makers to improve their understanding of thinning impacts on water and carbon exchanges in forest ecosystems and select and adopt viable forest management practices to enhance their carbon sequestration capabilities, water use efficiency and resilience to climate change.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: HYSTERIA AND ITS DESCENDANTS: A HISTORY OF GENDERED WASTEBASKET DIAGNOSES

contributor:
Balcom, Karen
History

subject:
hysteria
fibromyalgia
chronic fatigue syndrome
DSM
neurasthenia
gender
sexism
misogyny
medicine
psychiatry

abstract:
Hysteria has been researched from many different angles, but this thesis focuses on the
persistence of gendered medical diagnoses following the demise of hysteria. In Chapter One,
I provide an overview of hysteria’s long history, beginning with the first reference to the
disorder in Ancient Egypt. I then conduct a study of nineteenth-century hysteria in Chapter
Two, where I highlight the interactions between medicine and culture that characterized the
hysteria epidemic in Victorian Britain and America. Chapter Three continues this discussion
of nineteenth-century hysteria, detailing the rise of psychological explanations for hysteria in
Europe. My most important research, however, comes in Chapters Four and Five where I
chronicle the rise of specific diagnoses that replaced hysteria in the twentieth century. I focus
on gendered wastebasket diagnoses—illnesses that predominantly affect women, are
categorized based on shared symptoms rather than causes, and are defined in relation to
femininity. In the Diagnostic and Statistical Manual of Mental Disorders (DSM), the
descriptions of certain psychiatric conditions that are more frequently diagnosed in women
contain stigmatizing language used to describe hysteria, especially in the nineteenth century.
Outside of the psychiatric realm, chronic fatigue syndrome and fibromyalgia are also
wastebasket diagnoses that are described by both doctors and academics using the dismissive
language of earlier descriptions of hysteria. I argue that throughout all of this history, the
mutual influence of medical theory and cultural assumptions—particularly about gender and
femininity—has allowed women’s mysterious medical complaints to remain unexplained.
The ambiguous nature of conditions descended from hysteria and their association with
femininity causes doctors to return to long-standing stereotypes that diminish the suffering of
these patients. Many patients with these conditions struggle to access effective treatments for
their symptoms. Understanding these illnesses in the historical context of hysteria can help
explain and address these experiences.

abstract: Thesis

abstract: Master of Arts (MA)

abstract:
The medical field has long been influenced by its surrounding cultural context. Social factors,
including gender, race, and class, all colour the ways in which illnesses are understood and
patients are treated. This thesis examines these interactions between medicine and culture in
the context of nineteenth-century hysteria and the related diagnoses that arose to replace it in
the twentieth century. The disease entity hysteria disappeared in the early twentieth century,
but patients continued to experience the symptoms associated with hysteria under a range of
diagnostic titles. Situating these illnesses in the historical context of hysteria can help address
patient complaints and deconstruct the stigmatizing stereotypes that affect these patients—
particularly those stereotypes associated with femininity that were once attributed to hysteria
patients


title: THERMAL HYDRAULIC PERFORMANCE OF AN OSCILLATING HEAT PIPE FOR AXIAL HEAT TRANSFER AND AS A HEAT SPREADER

contributor:
Ching, Chan
Mechanical Engineering

subject:
Flat plate oscillating heat pipe
Stacked oscillating heat pipe
Thermo-hydrodynamics
Heat spreading

abstract: In this thesis, a stacked double-layer flat plate oscillating heat pipe charged with degassed DI water was designed, fabricated and characterized under different operating conditions (orientation, system or cooling water temperature and heat load). The oscillating heat pipe was designed to dissipate 500 W within a footprint of 170 x 100 mm2. The oscillating heat pipe had a total of 46 channels (23 channels per layer) with a nominal diameter of 2 mm. Tests were performed to characterize the performance of the oscillating heat pipe for (i) axial heat transfer and (ii) as a heat spreader. The stacked oscillating heat pipe showed a distinctive feature in that it overcame the absence of the gravity effect when operated in a horizontal orientation. The thermal performance was found to be greatly dependent on the operational parameters. The oscillating heat pipe was able to dissipate a heat load greater than 500 W without any indication of dry-out. An increase in the cooling water temperature enhanced the performance and was accompanied with an increase in the on/off oscillation ratio. The lowest thermal resistance of 0.06 K/W was achieved at 500 W with a 50℃ cooling water temperature, with a corresponding evaporator heat transfer coefficient of 0.78 W/cm2K. The oscillating heat pipe improved the heat spreading capability when locally heated at the middle and end locations. The thermal performance was enhanced by 27 percent and 21 percent, respectively, when compared to a plain heat spreader.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Improving Adoptive Cell Therapy to Overcome Tumor Resistance

title: MS-275 Enhances Antitumor Immunity During Adoptive Cell Therapy to Overcome Tumor Resistance

contributor:
Wan, Yonghong
Medical Sciences

subject:
Cancer Immunotherapy
Adoptive Cell Therapy
MS-275
HDAC Inhibitor
Tumor Resistance
Immunosuppression
T Cell Exhaustion
Epigenetic Reprogramming

abstract:
Cancer immunotherapy has gained attention in recent years for its successes in potentiating immune responses that can elicit tumor control. In particular, adoptive cell therapy (ACT), which involves the autologous/allogeneic transplant of ex vivo-cultivated tumor-specific T lymphocytes, can mediate potent tumor recognition and killing; however, durable clinical responses are often difficult to obtain in solid tumors. Solid tumors and their unique microenvironments have the capacity to evade and suppress antitumor immune responses and represent significant hurdles for effective ACT. Recently, we have discovered that chemical inhibition of histone deacetylases via MS-275 (Entinostat) during ACT can subvert tumor resistance to foster potent, broad-spectrum antitumor immunity. Overall, the work described supports the efficacy of ACT in the treatment of immunosuppressive, solid tumors; however, consistency in durable clinical outcomes can only be achieved through the concurrent therapeutic targeting of tumor resistance mechanisms.

This thesis uses pre-clinical models to describe how tumor resistance to ACT can manifest, and demonstrates that concurrent MS-275 delivery drives extensive immunomodulation to promote sustained tumor clearance. This includes:

1)	The polarization of tumor-infiltrating myeloid cells into cytotoxic effectors with the ability to reject immune escape variants
2)	The inflammatory remodeling of the tumor microenvironment to potentiate epitope spreading against secondary tumor antigens
3)	The transcriptional reprogramming of adoptively transferred T cells to overcome tumor-burden-dependent exhaustion

We expect that the results will help facilitate the development of next-generation ACT platforms that will feature strategies for multi-mechanistic perturbation of tumor resistance.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: The host immune system has the ability to recognize and destroy tumor cells. Therapeutic platforms that leverage antitumor immune cells, specifically T cells, have shown potency in the elimination of cancer. In the clinic, cancer immunotherapies have demonstrated early success against hematological malignancies; however, are unreliable in the treatment of solid tumors. Solid tumors utilize intrinsic and adapted mechanisms of resistance to mitigate the effectiveness of cancer immunotherapy. This thesis pursues research questions aimed at understanding how tumors resist immunotherapy, what mechanisms are utilized, and how to overcome these obstacles. We anticipate that these results will contribute to the development and incorporation of strategies to subvert tumor resistance and potentiate T cells against solid tumors.


title: Statistical Properties of Language Affecting Word Recognition During Natural Reading

contributor:
Connolly, John
Kuperman, Victor
Cognitive Science of Language

subject:
Psycholinguistics
Reading
Word recognition
Co-registration of EEG and eye-tracking

abstract:
Most previous research has explored how words are processed in isolation. However, reading is a complex process where an interplay of various factors affects word identification. Moreover, previous research has mainly focused on alphabetical languages, so extension of the existent findings to non-alphabetical languages is crucial. The current dissertation uses natural reading paradigms to study eye-movements and neurophysiological correlates of the statistical properties of words that affect word recognition during natural reading in English and Chinese.
Chapter 2 concerns the time-courses of word frequency and semantic similarity effects in the reading of English derived words. Previous research pointed to a paradox where behavioural experimental techniques showed earlier signatures of these properties than neuro-imaging techniques. By combining eye-tracking and EEG and applying analytical techniques that target the onset of these effects, this study aims at investigating this paradox. Results still show that neurophysiological responses are either largely absent or appear at the same time as shown in eye-movement data.
Chapter 3 shows that the existence of spelling errors negatively impacts the recognition of correct spellings in Chinese. This is revealed by the “spelling entropy effect”, which measures the uncertainty about choosing between correct and alternative spelling variants. This is the first study that used co-registration of eye-tracking and EEG to explore the behavioral and neurophysiological signatures of this uncertainty.
Chapter 4 studies how segmentation probabilities influence word segmentation and identification when reading Chinese. The results reveal that space becomes beneficial only when located at places where segmentation probability is considered high. This study is among the first to show beneficial effects of spacing at the sentence level and demonstrates how segmentation probabilities play a crucial role in Chinese word segmentation.
Cumulatively, the results obtained point to the existence of numerous factors involved in word identification in both alphabetic and logographic languages, which should be explored using natural reading experimental paradigms, such as co-registration of EEG and eye-tracking, for obtaining a multifaceted view of word recognition processes.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Overcoming the Curse of Missing and Noisy Data in Computational Drug Design

contributor:
Ayers, Paul
Chemistry and Chemical Biology

subject:
machine learning
computational drug design
matrix completion
missing value
Δ-Learning
imbalanced learning

abstract:
Machine learning (ML) has enjoyed great success in chemistry and drug design, from designing synthetic pathways to drug screening, to biomolecular property predictions, etc.. However, ML model's generalizability and robustness require high-quality training data, which is often difficult to obtain, especially when the training data is acquired from experimental measurements. While one can always discard all data associated with noisy and/or missing values, this often results in discarding invaluable data.
This thesis presents and applies mathematical techniques to solve this problem, and applies them to problems in molecular medicinal chemistry. In chapter 1, we indicate that the missing-data problem can be expressed as a matrix completion problem, and we point out how frequently matrix completion problems arise in (bio)chemical problems. Next, we use matrix completion to impute the missing values in protein-NMR data, and use this as a stepping-stone for understanding protein allostery in Chapter 2. This chapter also used several other techniques from statistical data analysis and machine learning, including denoising (from robust principal component analysis), latent feature identification from singular-value decomposition, and residue clustering by a Gaussian mixture model.
In chapter 3, Δ-learning was used to predict the free energies of hydration (Δ𝐺). The aim of this study is to correct estimated hydration energies from low-level quantum chemistry calculations using continuum solvation models without significant additional computation. Extensive feature engineering, with 8 different regression algorithms and with Gaussian process regression (38 different kernels) were used to construct the predictive models. The optimal model gives us MAE of 0.6249 kcal/mol and RMSE of 1.0164 kcal/mol. Chapter 4 provides an open-source computational tool Procrustes to find the maximum similarities between metrics. Some examples are also given to show how to use Procrustes for chemical and biological problems. Finally, in Chapters 5 and 6, a database for permeability of the blood-brain barrier (BBB) was curated, and combined with resampling strategies to form predictive models. The resulting models have promising performance and are released along with a computational tool B3clf for its evaluation.

abstract: Thesis

abstract: Doctor of Science  (PhD)


title: THE ENDOPLASMIC RETICULUM STRESS RESPONSE IN THE PROGRESSION OF SANDHOFF DISEASE

contributor:
Igdoura, Suleiman
Biology

subject:
Lysosomes
ER stress
Sandhoff Disease
Neurodegeneration

abstract: Sandhoff disease (SD), a fatal lysosomal storage disease, results from a deficiency of the β-subunit of the β-hexosaminidase A and B enzymes. This deficiency leads to severe accumulation of GM2 gangliosides in lysosomes within the central nervous system (CNS) resulting in mass neuronal apoptosis. The mouse model of SD shows progressive neurodegeneration that closely resembles Sandhoff and Tay Sachs disease (TSD) in humans. SD and TSD consist of infantile, juvenile, and late-onset forms. These diseases can present with a multiplicity of symptoms including cognitive and speech impairments, ataxia, and lower motor neuron disease. Late-onset SD and TSD show motor neuron disease in over 40% of patients. In this study, we explore the role of endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) in the spinal cord during the development and progression of disease in Sandhoff mice. Using immunocytochemistry and western blotting, we analyzed the expression level and localization of several ER stress and cellular apoptosis markers within the cervical, thoracic, and lumbar regions of the spinal cord of Sandhoff mice. Our results revealed significant upregulation of several ER stress markers in motor neurons that appeared to coincide with significant lysosomal accumulations. In addition, we observed sequential and age-dependent expression changes in ATF6 and CHOP and their prominent nuclear localization within anterior horn motor neurons. Markers of apoptosis, caspases and PARP also appeared to be activated in the spinal cords of Sandhoff mice starting as early as 60 days. Interestingly, we noted more than 50% reduction in neuronal numbers in all regions of the spinal cord of Sandhoff mice between ages 80 and 120 days. Overall, this study provides strong evidence for the role of chronic ER stress and UPR activation in the spine pathophysiology of SD.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Lysosomal storage diseases are a rare group of inherited neurological disorders that are often fatal at a young age. Two diseases that fall within this category, Sandhoff and Tay Sachs disease, are similar in their cause and symptoms. Current research lacks a complete understanding of the mechanism behind these disorders making the development of new therapeutics challenging. This research highlights a group of cells in the spine that are vulnerable in these diseases. These cells show physical and functional changes in their structure as the diseases progress. We provide evidence of a new stress pathway which appears to be strongly implicated in the development and progression of these diseases. We also show an association between this pathway and the death of these vulnerable cells leading to the symptoms exhibited by patients. These findings expand our current knowledge of these disorders and open new avenues for therapeutic interventions.


title: IMPROVING OUTCOMES FOR CANCER IMMUNOTHERAPY

contributor:
Mossman, Karen
Biochemistry and Biomedical Sciences

subject:
Cancer
Immunotherapy
Cancer Immunology
Oncolytic Virus

abstract:
Cancer is the leading cause of death in Canada and one of the leading causes of
death worldwide. Conventional cancer therapies such as chemotherapy often include severe side effects that can decrease the quality of life of patients undergoing treatment. Immunotherapy is designed to harness the host immune response and enhance its ability to
seek out and kill cancer cells. Immunotherapy has gained traction in the past decade due to
its improved safety and efficacy over conventional cancer therapies. However, there is
room for improvement as most patients fail to respond to immunotherapy. The work described in this dissertation involves the development of therapeutic combination platforms
that are designed to improve upon immunotherapy outcomes. Murine tumor models were
used to develop a better understanding of biological processes associated with therapeutic
efficacy. These findings can be used for the development of therapeutic strategies that can
further improve the efficacy of cancer immunotherapy.

abstract:
Cancer immunotherapy has demonstrated immense promise in the past decade. Immune checkpoint therapy has shown unprecedented responses in many cancers; however
most patients fail to respond to checkpoint therapy. This highlights the need to develop a
better understanding of factors in the tumor microenvironment that can influence therapeutic outcomes.
In this body of work, we have utilized oncolytic viruses (OVs) to enhance immunogenicity in the tumor and study the cellular mechanisms that enable a therapeutic response. We utilize a combination of OVs and low dose chemotherapy to further sensitize
murine models of mismatch repair-deficient colorectal cancer to checkpoint therapy. Using
a Clariom S transcriptome assay we found that the combination induced gene signatures
associated with the recruitment and activation of myeloid subsets. When we assessed tumor
infiltrates, we found that the combination induced the chemoattraction of several myeloid
subsets, including type I conventional DCs (cDC1s) which are known for their role in antigen presentation. Using Batf3-/- mice, we demonstrated that the therapeutic efficacy of
our combination platform was dependent on the presence of cDC1s.
In this dissertation, we also studied the role of OV-induced type I IFN (IFNI) in enabling or suppressing antitumor immunity. We found that OVs induced the upregulation of PD-L1 in an IFN-I-dependent manner in cancer cells and circulating immune
cells. Inhibition of IFN-I signaling using an anti-IFNAR monoclonal antibody partially
prevented OV-induced upregulation of PD-L1. Furthermore, the combination of OV and
v | P a g e
IFNAR blockade enhanced the effector functions of tumor-specific T cells and led to better
tumor control compared to OV monotherapy.
Altogether, these findings demonstrate that OVs can be an effective agent for enhancing immunogenicity in the tumor and promoting the infiltration of inflammatory myeloid subsets. By combining OVs with checkpoint or IFNAR inhibitors, we prevent the
onset of immunosuppression and enable a favorable therapeutic response.

abstract: Thesis

abstract: Doctor of Philosophy (Medical Science)


title: Evaluating the Migration Motives and Post-Migration Experiences of Iranian Dental Graduates Who Migrate to Ontario, Canada

title: Migration Motives and Integration Experiences of Iranian Dental Graduates in Canada

contributor:
Randall, Glen
Global Health

subject: Dentists Immigration Integration Canada

abstract:
Many healthcare professionals from lower-income countries seek to improve their circumstances by immigrating to higher-income countries. However, successfully integrating into these different socio-cultural environments can be a challenge and, as a result, the skills these individuals bring may be underutilized. While substantial research around immigration experiences of physicians and nurses appear in the literature, little is known about the experiences of dentists. This study explored the migration motives and post-migration experiences of Iranian dentists living and working in Ontario, Canada.  The intention was to identify potential barriers and facilitators of their integration in order to identify practical solutions to improve their experiences.
Following a qualitative approach, eleven personal interviews were conducted through the Zoom platform. A semi-structured interview guide consisting of two main areas of migration motivation and post-migration integration was used. Interviews were conducted in English and thematically analyzed through Dedoose software.
Socio-political and economic issues, including poor governance, political repression, currency devaluation, and incompatible social ethos were the main reasons behind Iranian dentists migrating to Canada. Canada’s multicultural friendly environment, along with peace and stability, were reported as the major pull factors of migration. However, participants experienced significant challenges, especially in terms of integrating into Canadian society and the process of having the equivalency of their dental education evaluated. These barriers were categorized into two main themes, including “socio-cultural” and “institutional” problems. Language barriers, tough and stressful equivalency examinations, and lack of familiarity with the Canadian dental system were key issues. However, ethnic networks, family supports, and examination preparation courses were identified as mitigating factors that facilitated a more positive migration experience.
Findings reveal that Iranian dentists and their families are stressed both financially and emotionally, mainly throughout the dental qualifications equivalency process; many applicants are unsuccessful in having their qualifications recognized or at least in a reasonable time period. The skills they bring are therefore not benefiting either themselves or Canada. Meanwhile, it appears that a systematic and institutionalized bias against foreign-trained dentists, including Iranian dentists, makes the process even more difficult. Regulatory college and board examinations may intentionally or unintentionally serve to limit foreign-trained dentists’ access to practicing for several reasons including racial attitudes or saving jobs for Canadian trained dentists.
Several recommendations to improve the situation are identified.  The National Dental Examining Board of Canada (NDEB) needs to revise its strategy by enhancing information about the equivalency and licensing process while providing information about mental health supports and financial aids for international applicants. Shadowing program opportunities and general orientation courses for international dentists could help International Dental Graduates’ (IDGs) to learn about dental system and practice dentistry in Canada.

abstract: Thesis

abstract: Master of Health Sciences (MSc)

abstract: This case study used in-depth interviews to study Iranian dentists who migrate to Canada. The main goal was to identify factors that impact full integration into Canadian society. Barriers to determining the equivalency of their qualifications was the predominant obstacle which put financial and emotional stress on applicants and their families. The system may have been set up in a way that systematically disadvantages foreign-trained dentists. In order to ensure maximal use of these oral healthcare professionals in Canada, it is necessary to facilitate the integration process through enhancing support networks and making available examination preparation courses.