Faculty of Graduate Studies Online Theses

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Access status: Open Access ,
EXPLORING EXPERIENCES OF A PILOT INTERGENERATIONAL PLAY PROGRAM IN NOVA SCOTIA, CANADA.
(2025-12-23) MacRae, Caitlyn; Not Applicable; Master of Arts; School of Health & Human Performance; Received; n/a; Not Applicable; Dr. Son Truong; Dr. Michelle Stone; Dr. Sara Kirk
Physical inactivity and social isolation are two pressing public health concerns in Nova Scotia, particularly among older adults. Intergenerational play (IGP) has emerged as a promising community-based strategy to address these issues by promoting both physical activity (PA) and social connection (SC). This thesis describes a study designed to explore the factors that influence participation in “Free for All” (FFA), a locally developed IGP program modeled after ParkPlay in the United Kingdom. FFA offered one free drop-in session in Halifax during the summer of 2024. Guided by a constructivist worldview and framed by the Social Ecological Model (SEM), this study employed a qualitative design to understand participant experiences. Data were collected through semi-structured interviews with participants to explore personal experiences, barriers, and facilitators to participation in FFA. Data were analyzed using reflexive thematic analysis, and three themes were generated: 1) Negotiating entry into play: ‘on ramps’ matter, (2) Play as an intergenerational equalizer: children open doors and adults walk through them, and (3) The fragile infrastructure of belonging: material conditions build social connections. The findings of this study contribute to a growing body of knowledge that IGP can serve as an inclusive, community-based health promotion strategy to promote PA and SC. Findings highlight the importance of cost-free design, child-led openness and supportive facilitation to promote participation. They also suggest that material and environmental conditions, such as accessibility and program continuity, are critical for sustaining participation and connection. Together, these insights have created a framework to implement IGP in Nova Scotia.
Access status: Open Access ,
The combinatorial game theory of Reverse Hex
(2026-01-13) Jeremiah, Hockaday; Not Applicable; Master of Science; Department of Mathematics & Statistics - Math Division; Not Applicable; n/a; Not Applicable; Richard Nowakowski; Julien Ross; Peter Selinger; Svenja Huntemann
Rex, short for Reverse Hex, is a set coloring game in which players try to avoid connecting terminals of their color. Combinatorial game theory (CGT) is the study of perfect strategy games. Until recently, both Rex and Hex were not examined through the lens of CGT. In this thesis we take inspiration from the study of normal play games by Berlekamp, Conway, and Guy, along with the combinatorial game theory of Hex developed by Selinger, to develop methods for analyzing Rex positions. We explore how to tell if one position is preferable to another, how to simplify positions, and some special properties of Rex (and antimonotone set coloring games in general). By the end of this thesis we will be able to take a position in a game of Rex, break it into smaller positions, analyze each of the smaller positions, then add the results back together.
Access status: Open Access ,
The Experience of Persistent Infertility: Beyond the Medical Model
(2026-01-09) Redgrift, Lisa; No; Doctor of Philosophy; Department of Sociology & Social Anthropology; Received; Dr. Sarah Earle; No; Dr. Fiona Martin; Dr. Brenda Beagan; Dr. Emma Whelan
This research explores the experience of persistent infertility among 15 childless Canadian women who discontinued fertility treatments when they did not work, who could not access assisted conception, and/or whose infertility is untreatable. By investigating how women understand their experience with persistent infertility and examining the parallels and divergences within and across the participants’ experiences, this analysis indicates that women’s fertility is an intricate lifelong journey, and persistent infertility disrupts this journey in ways that are biological, social, and gendered. Further, persistent infertility fractures the complex relationship between the body and the self. This research theorizes the embodiment of persistent infertility and the meaning placed on reproductive loss events (e.g., failed embryo transfer, miscarriage, and stillbirth), by the women in this study. Lastly, in the medicalized Canadian context, persistent infertility illustrates that hope for maternity is commodified, stratified, and reenforces the biological standard of normative motherhood.
Access status: Open Access ,
EXAMINING THE ASSOCIATION BETWEEN BREAST CANCER TREATMENTS AND SELF-REPORTED SEXUAL DYSFUNCTION IN CANADIAN WOMEN: A POPULATION-BASED CROSS-SECTIONAL STUDY
(2026-01-09) NISHIMAGIZWE, PATIENCE; Not Applicable; Master of Science; Department of Community Health & Epidemiology; Not Applicable; N/A; No; Dr. Jennifer Payne; Dr. George Kephart; Dr. Robin Urquhart; Dr. Cindy Feng
Background The prevalence of female breast cancer survivors in Canada has increased from 1.8% to 2.1% (2007-2021). Sexual dysfunction is a common long-term side effects of breast cancer treatments. Objective To estimate the prevalence of self-reported sexual dysfunction among breast cancer survivors in Canada and examine the association between of single and combined treatment modalities and sexual dysfunction. Methodology This cross-sectional study utilized data from 3772 participants who participated in the 2016 Experiences of Cancer Patients. The outcome was sexual dysfunction. The exposures chemotherapy, radiotherapy, and endocrine therapy. Multivariable logistic regression models were used to evaluate associations. Results Sexual dysfunction was most prevalent among survivors treated with chemotherapy (48.3%). Chemotherapy, endocrine therapy, radiotherapy, and combined modalities were associated with sexual dysfunction, with the highest odds observed among those receiving all three treatments. Conclusion Sexual dysfunction is common among Canadian breast cancer survivors and is associated with all treatment modalities.
Access status: Open Access ,
A Whale With No Name: Search for an unknown long-duration beaked whale (Cetacea; Ziphiidae) signal across ocean basins
(2025-12-28) Runte, Kiersten; Not Applicable; Master of Science; Department of Biology; Not Applicable; n/a; Not Applicable; Bruce Martin; Andy Horn; David Barclay; Hal Whitehead
Beaked whales (Cetacea: Ziphiidae) are known for producing frequency-modulated (FM) echolocation signals that are characteristic of each species, yet several species still lack confirmed FM signal descriptions. A distinctive FM signal, long in duration, and occurring only at night, has previously been documented in the North Pacific, the western Gulf of Mexico, and the Gulf of Guinea, but its broader distribution has not been assessed. Here, carried out is a basin-wide analysis of numerous passive acoustic monitoring projects to identify additional regions where this signal is present. Our dataset comprised 19 monitoring efforts (156 total datasets) spanning latitudes from 72° N to 42° S. An automated detector-classifier (per file Precision = 1.00 and Recall = 1.00) was run on all audiofiles to identify possible detections, which were subsequently reviewed and confirmed manually. We report the presence of this FM signal in five previously unrecognized areas: along a glider transect (512 kHz) near the Canary Islands; on three bottom-mounted recorders (250–512 kHz) off Western Australia; and from a single detection on Blake’s Plateau in the southeastern United States. Across all monitoring sites, detections occurred only during local nighttime hours and were not observed at latitudes higher than 29° N or 19° S. The signal’s median centre and peak frequencies ranged from 51 to 67 kHz, its median duration from 500 to 630 μs, and its −10 dB bandwidth from 19 to 28 kHz. This FM signal remains the longest known among both identified and unidentified beaked whale FM signal types. Although the producing species has yet to be determined, the signal’s temporal and spectral features were remarkably consistent across ocean basins. These results extend the known distribution of this unique FM signal and highlight the value of broad, cross-regional acoustic collaborations in uncovering previously unrecognized regions of beaked whale vocal behaviour and biogeography.
Access status: Open Access ,
Confronting Acoustic Data Scarcity: A Physics-Informed Approach to Trustworthy Machine Learning in Canada's Arctic
(2025-12-28) Thomson, Dugald; Yes; Doctor of Philosophy; Department of Oceanography; Not Applicable; Peter Gerstoft; Yes; Dale Ellis; Stan Dosso; JF Bousquet; Sarah Fortune; David Barclay
This thesis presents a novel, data-centric framework for building trustworthy artificial intelligence for passive acoustic monitoring in the Arctic, a region increasingly challenged by climate change and geopolitical pressures. The research addresses model brittleness in ship-radiated noise classification, framing it as a data problem that can be solved through a systematic, iterative process of data exploration, diagnosis, and augmentation. A detailed analysis of ship-radiated noise using horizontal line array element data provides a characterization of the complex variability of acoustic signatures. The thesis quantifies the horizontal directionality of radiated noise from individual ships and the broad-scale impact on the ambient soundscape, leveraging a unique data opportunity presented by the COVID-19 pandemic. Using these insights, a human-in-the-loop methodology is developed to diagnose the specific failure modes of a custom deep neural network classifier. This is achieved by visualising how real-world variability, such as source-receiver range and operational state changes, manifests in the model's learned feature space. The thesis culminates by demonstrating a physics-informed data augmentation strategy as the solution to data scarcity and diagnosed failures. Through the generation of targeted, high-fidelity synthetic data, this approach measurably improves classifier robustness on unseen real-world data, providing a validated methodology for developing reliable automated passive acoustic monitoring systems in complex environments.
Access status: Embargo ,
COLLOIDAL QUANTUM DOTS-ASSISTED HYBRID PHOTOCATALYST FOR WASTEWATER TREATMENT
(2025-12-30) Madhu, Swedha; Not Applicable; Master of Science; Faculty of Agriculture; Not Applicable; NA; Yes; Dr Lord Abbey; Dr Kuljeet Grewal; Dr Gurpreet Singh Selopal
Water pollution from toxic organic dyes and industrial effluents poses a severe threat to ecosystems and human health, underscoring the urgent need for sustainable, efficient wastewater treatment technologies. Among various approaches, photocatalysis has emerged as a promising technique for pollutant degradation due to its cost-effectiveness and environmental compatibility. However, the performance of conventional photocatalysts is hindered by several critical limitations, including poor light absorption capability, toxicity of heavy-metal-based catalysts, rapid e⁻/h⁺ recombination, and limited recyclability. This thesis aims to overcome these challenges by developing eco-friendly colloidal Quantum Dots (QDs) based nanohybrids integrated with one-dimensional (1D) and zero-dimensional (0D) nanomaterials to achieve efficient charge separation, broadened light absorption, and improved photocatalysis. Furthermore, the influence of external stimuli, including magnetic fields (MF), electric fields, and piezoelectric effects, was investigated to enhance the photocatalytic degradation efficiency of toxic pollutants. Firstly, a novel Cu:Zn-In-Se2 QDs decorated Fe3O4 nanorods mesoporous films were employed for the photocatalytic degradation of methylene blue (MB) under the influence of an external MF. The optimized hybrid nanohybrid photocatalyst achieved a remarkable 99.96% degradation efficiency, representing a 49% improvement over the control Fe3O4 photocatalyst (67.01%). This enhanced performance was attributed to the synergistic effect of the broad light absorption of Cu:Zn-In-Se2 QDs/Fe3O4 and the efficient carrier dynamics facilitated by the Lorentz force in the presence of the MF. Additionally, the toxicity of treated methylene blue (MB) water was evaluated using Brassica oleracea (kale) as a model plant system. Plants irrigated with treated water exhibited superior growth compared to those irrigated with MB-contaminated water, confirming the reduced toxicity of the treated water and demonstrating its potential for safe agricultural reuse and sustainable wastewater management. Secondly, a hybrid photocatalyst composed of Mn:CuInSe2 QDs integrated with a mesoporous TiO2 film photoanode was developed and evaluated for the simultaneous photoelectrochemical degradation of Rhodamine B (RhB) and hydrogen generation. The optimized hybrid Mn:CuInSe2 QDs/TiO2 nanohybrid photocatalyst achieved a remarkable 93.31% degradation efficiency of RhB at an external bias of 1.4 V and a photocurrent density of ~4 mA cm-2 at 0.8V vs RHE. The results highlight the potential of Mn:CuInSe2 QDs/TiO2 nanohybrid as a dual-function photocatalyst for efficient and fast wastewater treatment and clean fuel production. Thirdly, the piezoelectric degradation of pollutants was investigated using ZnSnO3-based nanomaterials, demonstrating the capability of piezo-catalysis to degrade organic contaminants effectively. Overall, this research provides new insights into the design of novel eco-friendly Cu:ZnInSe2 QDs/ZnSnO3 nanohybrid photocatalysts and presents external-vibrational-stress-assisted photocatalysis for efficient environmental remediation and renewable energy generation.
Access status: Embargo ,
Constructing Igboness: Ethnicity, Culture, and Social Change in 20th Century Southeastern Nigeria
(2026-12-31) Abuba, Chioma; Not Applicable; Doctor of Philosophy; Department of History; Received; Professor Bonny Ibhawoh; Not Applicable; Dr. Gary Kynoch; Dr. Jonathan Roberts; Dr. Philip Zachernuk
Contrary to the dominant binary conceptions of Igboness (Igbo cultural identity) as either invented in response to colonial rule or an essence unchanged since early times, it is a dynamic, heterogenous, social construct which developed in continual dialogue with global knowledge systems and social currents. This idea is based on a study of Enugwu-Ukwu, a culturally iconic town in northern Igboland, in southeastern Nigeria, renowned as part of the nexus of Igbo culture and civilization. It traces how, over a century (1900-2000), local historical actors (chiefs, townspeople, town unions, women’s groups, etc.) engaged with local, colonial and global forces attempting to apply Omenana (Igbo cultural principles) to routinize a society undergoing the revolutionary changes of the 20th century. Using extensive archival records, oral interviews, museum collections, and primary and secondary literature, this study shows what changes occurred, who made them happen, how they achieved this, and why they tried.
Access status: Open Access ,
Investigating Turnover Intentions of Immigrant Software Engineers
(2026-01-06) Amedzor, Eyram; Not Applicable; Master of Computer Science; Faculty of Computer Science; Received; na; Not Applicable; Dr. Dirk Arnold; Dr. Lizbeth Escobedo Bravo; Dr. Rina R. Wehbe; Dr. Paul Ralph
Context: Software companies around the world rely on immigrant software engineers to fill their gaps in the workforce. However, immigrants leave their jobs at higher rates than native-born workers. Objective: Our objective is to investigate factors contributing to the increased turnover of software engineers with immigrant backgrounds. Methodology: We conducted a grounded theory study interviewing twenty software engineers with immigrant backgrounds originating from seven different countries. Results: Participants identified four primary factors that shape their turnover intentions: career stagnation, compensation, remote work preferences, and family. Social embeddedness---how connected individuals feel to their surrounding communities and institutions---served as a secondary factor, and immigration policies acted as constraints to actual turnover behavior. Recommendations: In order to reduce turnover, we recommend that organizations pay their immigrant engineers market rates, provide growth opportunities, and offer remote work options to enhance the retention of migrant engineers. For governments, we recommend implementing employer-agnostic visas, extending renewals for expiring visas, and funding programs that promote the cultural integration of new immigrants.
Access status: Open Access ,
Architectural Redeployment: Reestablishing Urban Identity in the Ruins of Renewal
(2026-01-06) Rice, Colby; Not Applicable; Master of Architecture; School of Architecture; Not Applicable; Rashida Zakia; Not Applicable; Catherine Venart; Roger Mullin
The town of Portland, New Brunswick, was hollowed by urban renewal and rebranded as the North End of Saint John, triggering the neighbourhood's downfall. With a second renewal on the horizon, occurring in the ruins of past plans, this thesis asks: How might an architect participate in the successful renewal of a neighbourhood? An exploration of place and placelessness as cultural conditions suggests that intuitively valuable urban fabric is most readily produced through a bottom-up construction that maintains a legible relationship between individuals and their architecture. To foster this high-energy individual investment, a valuable sense of localized urban identity is restored by reconstructing the town's erased primary element, St. Peter's Church. The ruins are reoccupied by a new town hall, redeploying autonomy and distinction to Portland. A fragmentary architectural design method is developed to help architects achieve the human density of detail and consideration that naturally emerges from place-based dwelling.
Access status: Open Access ,
ACTIVATED BIOCHAR FOR THE REMOVAL OF PESTICIDES FROM WASTEWATER: PREPARED FROM, FLAX SHIVES, Linum usitatissimum L.
(2025-12-29) Perera, Wellaweediyage Pubudi Ama; Not Applicable; Master of Science; Faculty of Agriculture; Not Applicable; Dr.Su-Ling Brooks; Not Applicable; Dr. Sonil Nanda; Dr. Rahil Changotra; Prof. Quan Sophia He; Dr. Yulin Hu
Activated biochar, characterized by high porosity and abundant surface functional groups, has been widely applied to treat wastewater. In this study, flax shives, as an agricultural residue, were converted to activated carbon by pyrolysis followed by chemical activation to remove pesticides, i.e., 2,4-dichlorophenoxyacetic acid (2,4-D) and imidacloprid (IMI) from water. The effects of pyrolysis temperature (300-500 ℃) and residence time (1-3 h) and activation using NaOH at a biochar: NaOH weight ratio of 1:1, 1:2, 1:3 and 1:4 at 700 ℃ for 1.5 h were investigated. The activated biochar (ABC-3) obtained at a biochar: NaOH weight ratio of 1:3 exhibited a specific surface area of 2292 m2g-1 and removed 95 % of 2,4-D and 100% of IMI respectively. The co-adsorption behavior of the two pesticides was also evaluated. Kinetic and isotherm analyses showed that 2,4-D adsorption followed a pseudo-second-order kinetic model and the Freundlich isotherm model while IMI adsorption fitted well with the pseudo-first-order kinetic model and the Langmuir isotherm. Overall, flax shives-derived activated biochar demonstrated strong potential as an efficient adsorbent for pesticide removal.
Access status: Open Access ,
Bridging Expertise Gaps in Safety-Critical System Monitoring: A User-Centred Design of Adaptive Visualization and Explainable AI for Elevator Systems
(2026-01-07) Anukem, Sussan; Not Applicable; Master of Computer Science; Faculty of Computer Science; Received; n/a; Yes; Rina Wehbe; Yujie Tang; Rita Orji
The operational failure of critical infrastructure like elevators directly impacts public safety and mobility. While modern elevators generate vast amounts of sensor data, translating this data into actionable insights for diverse user groups (from maintenance engineers to building managers), remains a significant challenge in the field of Human-Computer Interaction. Existing monitoring dashboards are often hindered by a one-size-fits-all approach, reactive architectures, and interfaces that assume domain expertise, thereby creating an expertise gap that impedes effective collaboration and situational awareness. Our work is a two-phase, user-centred research project that bridges this gap through an adaptive and intelligent monitoring system. In the first phase, a controlled study (n = 20) established an empirical foundation for visualization complexity, demonstrating that effectiveness is task-dependent, not universally simple or complex. These findings directly informed the second phase: the design and evaluation of a novel system that synergistically combines an adaptive visualization interface with an AI Assistant powered by a unified reasoning engine that provides both data-grounded prognostic reasoning and natural-language explanations. A comprehensive evaluation (n = 97) demonstrated the system's effectiveness. It achieved an outstanding usability score (SUS = 98.69, SD = 5.70), provided equitable performance across technical and non-technical users, and enabled a 100% diagnostic accuracy rate for AI-assisted potential fault diagnosis. Qualitative analysis revealed the AI assistant served as an "accessibility bridge" for non-technical users and a "productivity multiplier" for experts. The primary contribution of this work is a set of six empirically validated design principles for building inclusive safety-critical monitoring systems. This research demonstrates that moving beyond static interfaces to strategically adaptive interfaces, and reframing AI as an explainable collaborative partner through transparent prognostic reasoning, provides a viable path to bridging the expertise gap for multi-level users.
Access status: Open Access ,
Role of Absorptive Capacity in driving Artificial Intelligence based Digital Transformation Projects towards success
(2025-12-22) Anthonydura, Erandi; Not Applicable; Master of Digital Innovation; Faculty of Computer Science; Received; N/A; Not Applicable; Dr. Paola Gonzalez; Dr. Richard Evans; Dr. Fanny-Eve Bordeleau
With Artificial Intelligence (AI) gaining increasing attention in the industry, digital transformation (DT) based around the technology has become imperative for organizations seeking positive business outcomes. Firms embark on AI‑based DT journeys influenced by technological, organizational, and environmental factors, yet success depends on how these forces are strengthened by the inherent absorptive capacity. This study employed a semi‑systematic literature review of 34 articles to understand the specific role of digital absorptive capacity and to build the conceptual model. An initial plausibility assessment supported by deductive coding and analysis was conducted through a positivist interviewing approach involving four industry experts from Technology business sector, during October 2025. Findings provided preliminary support for the proposition, and identified external support as a critical environmental construct within the TOE framework. These findings contribute to the evolving theoretical perspectives on AI‑driven DT and absorptive capacity. The study also urges practitioners and policy makers to mobilize resources and strengthen support mechanisms in favor of AI-based DT.
Access status: Open Access ,
We must be Very Ignorant or Very Wicked: The Foundation of the Native Baptist Church in Jamaica, 1783-1841
(2025-12-22) Samson, Francis; Not Applicable; Master of Arts; Department of History; Not Applicable; n/a; Not Applicable; Jerry Bannister; Isaac Saney; Justin Roberts
In 1783, a former slave named George Liele fleeing the American Revolution started the first Baptist church in the British colony of Jamaica. For the next few decades, Liele’s organization would grow into a network of Black-led Baptist churches. In 1814, the Baptist Missionary Society sent British preachers to take over the existing network of churches after the colony outlawed the original Baptist preachers. And in 1831, an enslaved deacon named Samuel Sharpe in a British missionary’s church started the Baptist Rebellion, the largest slave revolt in British history, accelerating the date of emancipation up to 1833-1834. While nominally controlled entirely by White missionaries, enslaved leaders created a second leadership structure within the church that continued the legacy of Liele’s original Baptists. After the end of slavery in Britain, growing discontent with the suppression of Black leaders in the church would lead to the formation of the Native Baptist church.
Access status: Open Access ,
9/11 and the War on Terrorism: What It Means for Canadian Islamic Organizations
(2025-12-31) Bin Awal, Arefin Noman; Not Applicable; Master of Arts; Department of International Development Studies; Not Applicable; n/a; Not Applicable; Dr. David Black; Dr. Ajay Parasram; Dr. John Cameron
This thesis explores the impact of post-9/11 counterterrorism policies on Muslim charities and non-profit organizations in Canada. Following the September 11 attacks, Canada introduced a series of legislative and regulatory measures, including the Anti- Terrorism Act (2001) and the Proceeds of Crime (Money Laundering) and Terrorist Financing Act, which expanded state surveillance and enforcement powers. Drawing on secondary sources, this research analyzes how these policies disproportionately affected Muslim-led organizations through audits, revocations of charitable status, and heightened scrutiny. The study situates these developments within broader international pressures, especially from the United States and the United Nations, and critically examines their implications for civil liberties, multiculturalism, and the role of Islamic civil society in Canada. By mapping the intersections between national security, legal reform, and racialized governance, the thesis contributes to a growing body of scholarship on securitization and the marginalization of minority communities in the post-9/11 era.
Access status: Open Access ,
THE SHADE EFFECT: HOW COLOURISM AND SKIN TONE SHAPE SOUTH ASIAN CONSUMERS’ PERCEPTION IN ADVERTISING
(2025-12-22) Tassnim, Zarin; No; Master of Science; Business; Received; N/A; Not Applicable; Dr. Dr. Hamed Aghakhani; Dr. Mohammed El Hazzouri; Dr. Alexandria West; Dr. Valerie Trifts; Dr. Thomas K.B. Koo
Colourism, the preference for lighter skin tones over darker ones within and between racial and ethnic groups, remains a persistent issue across many cultures, particularly among South Asians, as well as in media and advertising. Yet very little marketing research has examined how skin-tone representation in advertising shapes South Asian consumers’ perceptions when viewing another South Asian individual with a lighter or darker skin tone. This research investigates whether South Asian consumers respond differently to advertisements featuring lighter-skinned versus darker-skinned South Asian models. Using an experimental design, participants were randomly assigned to view either a lighter- or darker-skinned South Asian model and then evaluated the model and the advertisement. They also completed measures of ideal self/model congruence, Social Dominance Orientation (SDO), and Right-Wing Authoritarianism (RWA). Contrary to expectations, there were no significant differences in consumer responses across the two skin-tone conditions. Ideal self/model congruence did not mediate the relationship between skin tone and attitude toward the model and ad. Likewise, neither SDO nor RWA moderated the association between skin tone representation and ideal self/model congruence. These findings suggest that consumers responded similarly to both lighter and darker-skinned models, highlighting the need for future research to examine whether colourism-based perceptions continue to shape South Asian consumers’ perceptions, how these attitudes may be changing, and what factors might contribute to such shifts in a multicultural context.
Access status: Open Access ,
A Long Term Analysis of Internal Migration and Climate Change as Drivers of Urban Growth and Slum-Like Housing in Kenya
(2026-01-07) Smaili, Ali; Not Applicable; Doctor of Philosophy; Department of Economics; Not Applicable; Franque Grimard; Not Applicable; Daniel Rosenblum; Dozie Okoye; Talan Iscan
Over 1.1 billion urban residents live in unacceptable conditions, lacking access to clean water, durable housing, and adequate sanitation. However, the drivers of this growing problem have been understudied due to a lack of granular data tracking the populations living in such conditions and their drivers. This dissertation fills these gaps by developing a dataset using four censuses for Kenya that tracks urban populations living in slum-like conditions and the drivers of urban population growth across urban centres from 1989 to 2019. This dissertation shows that the contribution of natural increase to urban population growth is larger than net in-migration in many urban centres and that the growth in urban centre populations living in slum-like housing is more strongly associated with natural increase. This dissertation also shows that climate change is a significant driver of net in-migration towards urban centres, potentially deepening the deficit of adequate urban housing in Kenya.
Access status: Open Access ,
Advanced Scalable Deposition of Polydimethylsiloxane for Both High and Low Energy Generation Applications
(2025-12-28) Kahwagi, Rashad; No; Doctor of Philosophy; Department of Process Engineering and Applied Science; Not Applicable; Dr. Simon Rondeau-Gagne; Yes; Dr. Alison Scott; Dr. Micheal Freund; Dr. Ghada Koleilat
Renewable energy generation has cemented itself as the main pillar in supplementing our future energy needs and subverting any crises in the next two to three decades. A complete shift towards sustainable generation has become the goal for most first-world nations, with much focus and resources being allocated for green energy research, infrastructure accommodations and sustainable energy generator implementation. From solar to wind, geothermal and mechanical energy, many research endeavors have been made to develop materials and processes capable of efficiently transforming these renewable resources into electricity, with a major focus placed mostly on large-scale production. However, sustainable material processing and smaller scale energy production are essential if the targets set are to be achieved, and research has been increasingly shifting towards it in the last decade. Small scale energy production through devices such as triboelectric nanogenerators have shown promise in the last decade, though they are still a long way from being appropriate mixtures to complement the impressive milestones reached so far at a bigger scale, as mostly complex engineered mixtures with complicated designs, high-cost materials and intricate processes have been crucial towards progress. Such an approach has come at great costs and incompatibility with current industrial processes and infrastructure. Hence, there is still a need for cost-effective and reliable material and process design. Throughout this thesis, the proposed work shows an alternative process called capillary climb film formation (CCFF) for thin film PDMS production, a material ubiquitous with renewable energy production among many other applications in fields such as medicine and microfluidics. The capabilities of this technique are thoroughly explored to better understand its limitations and highlight the advantages that it presents compared to other more traditional means of thin film production. Using CCFF, it is possible to form a large thin film from a small volume of PDMS mixture, while controlling its surface morphology on both sides pre-curing, combining the process of film formation and structuring into a simple single step. The technique also showed compatibility with vertical and horizontal capillary climb, which opens the door for single-step multi-film production. In addition to great control of the film’s structure, properties such as film thickness, material transparency, hydrophobicity and intricate internal designs can also be manipulated to obtain the desired results. Furthermore, the versatility of CCFF was demonstrated in its breadth of applicability, as the technique was employed to produce capacitive sensors, repair damaged films through the formation of a larger connected single film from torn pieces, as well as successfully encapsulate perovskite solar cells and improve their stability immensely, transforming them into devices that last over 60 days at peak performance in harsh conditions as opposed to ones that lose all their performance in less than 10 days. In terms of power generation, CCFF was used to obtain a PDMS thin film that would act as a tribonegative layer opposite the repurposed tribopositive monofilament fabric in a contact-separation model of a triboelectric nanogenerator (TENG). The maximum power output with the traditional device build was 12.16 mW/m2 achieved at a load of 20 MΩ, with an open-circuit voltage of 16.63 V. The device was even able to charge a 1 µF capacitor to 1.4 V in less than a minute. However, leveraging the versatility of CCFF to build the TENG itself presents a unique opportunity to leverage the advantages of this technique by building the device in a single step, foregoing the need for artificial separators, and maximizing the contact between both tribolayers through PDMS mixture climb in all three x, y and z directions. The final outcome was a device capable of producing 25.17 mW/m2 at 10 MΩ, while powering the 1µF capacitor to nearly 2.5 V in less than thirty seconds, showing the ability of a CCFF-built TENG to provide electricity to low power devices, while streamlining the building process and simplifying it.
Access status: Open Access ,
Testing the feasibility of a corticospinal excitability assessment system
(2026-01-05) Stadnyk, Connor; Not Applicable; Master of Science; School of Health & Human Performance; Received; Dr. David MacArthur; Not Applicable; Dr. Heather Neyedli; Dr. Michel Ladouceur
To assess the contributions from cortical and spinal structures to motor output, it is necessary to stimulate cortical, thoracolumbar and peripheral nerve structures during voluntary contractions This feasibility study implemented a tri-modal (cortical, thoracolumbar, and peripheral nerve) stimulation protocol during isometric quadriceps contractions of varying levels. The first step consisted in the stimulation of the femoral nerve to obtain the maximal muscle response in the vastus medialis. Subsequently, thoracolumbar and transcranial stimulation intensities that evoked responses equal to 20 percent of the maximal femoral stimulation muscle response were determined. Following the determination of the individual stimulation intensities, cortical, thoracolumbar, and peripheral nerve stimulation were delivered in a pseudorandom manner for all stimulation modalities and muscle contraction levels (25, 50, 75, and 90 percent maximum voluntary contractions) while recording the surface electromyography responses from the vastus medialis. It was possible to run the full protocol of three of the five participants, but further development would allow for future research on corticospinal and spinal excitability.
Access status: Embargo ,
ASSESSING THE ROLE OF BAF SUBUNIT VARIANTS IMPLICATED IN NEURODEVELOPMENTAL DISORDERS USING DROSOPHILA-BASED FUNCTIONAL ASSAYS
(2025-12-18) Edison, Abigail C.; Not Applicable; Master of Science; Department of Biochemistry & Molecular Biology; Not Applicable; n/a; Not Applicable; Dr. Aarnoud van der Spoel; Dr. Johane Robitaille; Dr. Francesca Di Cara; Dr. Jamie M. Kramer
Neurodevelopmental disorders (NDDs) are frequently caused by variants in genes associated with chromatin regulation, interfering with transcriptional programs that support normal neurodevelopment. These genes include subunits of the Brahma-associated factor (BAF) chromatin-remodelling complex. Functional assays in the model organism Drosophila can inform whether an NDD-associated variant alters the function of the encoded protein. Here, I employed a Drosophila assay to assess variants in the BAF subunit SMARCD1. Knockout of Bap60, the fly orthologue of SMARCD1, is lethal. The expression of human SMARCD1 rescues lethality, forming the basis for a ‘humanised rescue’ assay. I screened 22 SMARCD1 variants of uncertain significance and found a deleterious effect in seven, providing functional evidence that reclassifies the variants to likely pathogenic. Additionally, I developed alternative assays for the BAF subunits ACTL6A/B and SMARCA2/4. Overall, this work provides novel insight on the functional impact of NDD-associated BAF subunit variants, assisting in their clinical classification.

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