Faculty of Graduate Studies Online Theses

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Access status: Open Access ,
Development of Phenological Models and Management Strategies for Narrowleaf Goldenrod (Euthamia graminifolia L.) in Wild Blueberry (Vaccinium angustifolium Ait.) Fields
(2025-11-27) Hoeg, Lienna; Not Applicable; Master of Science; Department of Plant, Food and Environmental Sciences; Not Applicable; N/A; Not Applicable; Dr. Travis Esau; Dr. Andrew McKenzie-Gopsill; Dr. Scott White
Narrowleaf goldenrod (Euthamia graminifolia) has emerged as a major perennial weed challenge in wild blueberry (Vaccinium angustifolium) production in Nova Scotia, impacting crop management and yield quality. This thesis investigated the phenological development of E. graminifolia and evaluated integrated strategies for its control. Predictive models based on growing degree days were developed to accurately describe shoot emergence and flowering timing, enabling growers to better schedule post-emergence management. Narrowleaf goldenrod ramet emergence began at 25-71 GDD, and continued to 1,047-1,665 GDD across all study sites. Narrowleaf goldenrod ramets were observed at the flowering bud stage between 710 and 871 GDD (June 21 – 28), and approximately 90% of emerged ramets reached the flowering bud stage between 1303 – 1956 GDD (July 17 – August 24). Emerged ramets began flowering between 1418 – 1626 GDD (July 30 – August 7), and approximately 90% of emerged ramets were flowering between 1992 – 2225 GDD (August 27 – September 12). Cumulative E. graminifolia seedling emergence ranged from 2.4 ± 0.8 to 4 ± 1 seedlings m-2, respectively, and seedling density from soil core samples ranged from 0.02 ± 0.01 to 6.92 ± 1.80 seedlings per core. Seedbank and seedling recruitment studies indicated limited establishment of new plants through sexual reproduction in managed fields, highlighting the necessity of focusing on established populations. Herbicide field trials were established across eleven commercial lowbush blueberry fields in Nova Scotia between 2019 and 2021 to evaluate early-POST, late-POST, and post-harvest, pre-pruning herbicide applications. These studies identified mesotrione-based treatments and targeted fall applications as the most effective methods for long-term suppression with minimal crop injury. The research supports renewed registration efforts for key herbicide programs and provides practical recommendations for sustainable weed management, helping Nova Scotia blueberry growers address the threat of an increasingly dominant, competitive weed species.
Access status: Open Access ,
DYNAMIC BALANCE OF THE SUPPORTING LEG DURING UNILATERAL OBSTACLE CROSSING IN YOUNG ADULTS
(2025-11-25) Kebritchi, Afarin; No; Master of Science; School of Health & Human Performance; Received; Ryan Frayne; No; Derek Rutherford; Christopher MacLean; Michel Ladouceur; David McArthur
Walking biomechanics, especially during tasks requiring postural adjustments such as obstacle navigation, present complex neural and mechanical challenges. Successful obstacle negotiation relies on anticipatory locomotor adjustments and precise dynamic balance control. The present study investigates dynamic balance during unilateral obstacle crossing by examining center of mass behavior and its relationship to the center of pressure across obstacle heights from 0 to 60 cm. Specifically, it evaluates the COM–COP inclination angle and the supporting-leg COM velocity to characterize anticipatory locomotor adjustments and determine potential differences between right and left support limbs. We hypothesize that (A) the COM–COP IA will increase in forward–backward and decrease in side-to-side directions as obstacle height increases, and (B) COM velocity components will vary systematically with higher obstacles. We further propose that lateralization effects may emerge, with inter-limb differences becoming more pronounced at greater heights. This research aims to improve the understanding of adaptive gait strategies.
Access status: Open Access ,
UNDERSTANDING TRAVEL ACTIVITY IN THE DIGITAL ERA: MODELING TRAVELLER PROFILES AND INTERACTION BETWEEN ICT ACCESS, AND WORK ARRANGEMENTS
(2025-11-27) Ibnat, Atkia; Not Applicable; Master of Applied Science; Department of Civil and Resource Engineering; Received; N/A; Yes; Dr. Hamid Afshari; Dr. Lei Liu; Dr. Ahsan Habib
Advances in digital technology have changed how people work, socialize, and travel, yet most transportation planning still focuses on physical trips. This thesis explores how digital access and flexible work arrangements shape mobility and how transportation systems can adapt. It uses the 2024 Calgary CanTRAC Survey, which collected travel diaries and information on ICT ownership, online activity, and lifestyle preferences from 1,474 individuals. A two stage calibration corrected selection bias. Using this weighted dataset, k prototypes clustering identified three groups: Traditionalists, Hybrid Workers, and Active Professionals. A latent segmentation mixed logit model showed that technology access supports hybrid work, while job type and flexibility influence technology adoption. It introduces new ways to integrate digital participation into travel analysis and provides policy guidance to support flexible transit, digital inclusion, and more inclusive urban mobility.
Access status: Embargo ,
Women on the Water: The Feminine Seascape Onboard Nova Scotia’s Nineteenth Century Deepwater Merchant Sailing Vessels
(2025-11-25) McNutt, Brianna Grace; Not Applicable; Doctor of Philosophy; Department of History; Not Applicable; Dr. Heidi MacDonald; Not Applicable; Dr. Lisa Binkley; Dr. Aaron Wright; Dr. Jerry Bannister
Seafaring has long been considered as inherently masculine. This perspective has shaped the cultural legacy of Nova Scotian seafaring women, whose contributions to maritime industries are often forgotten or marginalized. This thesis challenges the dominant masculine seascape by establishing an equivalent feminine seascape. The feminine seascape recontextualizes ships as part of a woman’s household, a structure of power that bestowed married women with significant authority. By studying the life-writing of three Nova Scotian sea captains’ wives during the age of sail, as well as contemporary English-language newspapers and print culture, this thesis explores the paradoxical nature of women’s power within patriarchal systems, arguing that seafaring both challenged and reinforced ideals of Victorian married womanhood. Ideologies of domesticity provided sea captains’ wives with a discursive lens through which they could interpret maritime spaces and activities as normative for their phase of life. My thesis argues that this enabled captains’ wives to construct a multifaceted feminine seascape. It contributes to a growing field of gender history at sea and alters our understanding of captains’ wives. In doing so, it contributes to regional histories by positioning the experiences of rural, middle-class women as cosmopolitan and transnational, thereby disrupting the parochial and conservative narratives often attributed to, and occasionally embraced by, the Maritimes.
Access status: Open Access ,
From Aerosol to Climate Patterns: A Multi-Scale Study of Marine Fog Variability in Atlantic Canada and the Central Arctic
(2025-11-25) Duplessis, Patrick; Not Applicable; Doctor of Philosophy; Department of Physics & Atmospheric Science; Not Applicable; Adele Igel; Yes; Glen Lesins; Ian Folkins; Rachel Chang
Marine fog is a complex and under-constrained phenomenon shaped by interactions between aerosols, ocean conditions, and atmospheric structure. This thesis examines fog formation across two contrasting regions: the CCN-rich but increasingly unstable northwest Atlantic and the pristine, CCN-limited Central Arctic. Using in situ field observations, long-term climatology, and reanalysis data, the work identifies the key physical mechanisms controlling fog microphysics and variability. Field campaigns in Nova Scotia (2016) and the Central Arctic (2018) revealed distinct activation regimes. Nova Scotia fog featured activation diameters of 250–400 nm, reflecting an accumulation-mode aerosol population and size-dependent scavenging. Arctic fog instead activated ultrafine Aitken-mode particles (20–40 nm) under high supersaturations (0.3–1.0%) in a CCN-scarce environment, highlighting strong aerosol–supersaturation coupling. A 1953–2019 Sable Island analysis shows a shift from synoptic pressure control toward local thermodynamic regulation linked to warming SSTs. Together, these results illustrate two limiting fog regimes and underscore the need for models that capture both microphysical activation and evolving climate drivers.
Access status: Open Access ,
The Relative Importance of Social and Health Spending in Determining Health Outcomes Across Selected OECD Countries From 1990 to 2019
(2025-11-25) McCann, Bridget; Not Applicable; Master of Science; Department of Community Health & Epidemiology; Not Applicable; Not Applicable; Not Applicable; Mark Asbridge; Ruth Lavergne; Daniel Dutton
Governments in high income countries continue to prioritize health care spending to improve population health, yet evidence suggests that broader social factors also influence health. This study examined whether greater investment in social spending relative to health spending is associated with improved population health across 26 OECD countries from 1990 to 2019. Using standardized international data and two-way fixed effects regression models, we assessed the association between the ratio of social-to-health spending and five health outcomes: life expectancy, potential years of life lost, infant mortality, low birth weight, and maternal mortality. Higher social-to-health spending ratios were associated with better life expectancy, potential years of life lost, and infant mortality. Outcomes for low birth weight and maternal mortality showed inverse associations with the ratio over time. These findings suggest that redirecting government spending toward social programs may be a more effective way to improve health outcomes than prioritization of health spending.
Access status: Open Access ,
Adapting Eco-Driving Feedback and Historical Visualization for Vessel Dashboards
(2025-11-25) Rahman, Yeaminur; Not Applicable; Master of Computer Science; Faculty of Computer Science; Received; n/a; Not Applicable; Dr. Rita Orji; Dr. Stephen Brooks; Dr. Derek Reilly
Maritime navigation is a significant source of greenhouse gas emissions. While large-scale cargo shipping is the major contributor, smaller maritime operations, including patrolling, fishing, public transit, and recreation, present unique challenges and opportunities for power management. Fuel consumption, power conversion, and environmental data can permit environmentally conscious and cost-effective decision-making when driving a boat. To achieve this, we need to understand how best to integrate such data into boat dashboard interfaces. In this work, we design an Eco Dashboard inspired by eco-driving feedback dashboards in the automotive industry, as well as a variant of the Eco Dashboard that additionally visualizes historical route and fuel consumption data (Eco + Historical Dashboard). In an experimental simulation (N = 30) involving 12 experienced mariners and 18 novices, we compared both interfaces with a typical boat dashboard that presented fuel and speed. Our findings suggest that dashboards incorporating historical data, alongside eco-driving features, improve fuel efficiency and decision-making, particularly for non-experienced users. The Eco Dashboard supported real-time adjustments during complex navigation, whereas the Eco + Historical Dashboard enhanced route planning and confidence in longer-term decisions. Participants also reported greater confidence and reduced cognitive load when using these systems. These results provide valuable insights for the future design of maritime dashboard systems, offering a pathway to more effective and environmentally conscious navigation tools.
Access status: Open Access ,
KAPOSI’S SARCOMA-ASSOCIATED HERPESVIRUS REMODELS THE NUCLEUS AND ENDOPLASMIC RETICULUM DURING INFECTION
(2025-11-18) Wilson, Alexa; Yes; Doctor of Philosophy; Department of Microbiology & Immunology; Not Applicable; Dr. Sumita Bhaduri-McIntosh; Yes; Dr. Roy Duncan; Dr. Barbara Karten; Dr. Christopher Richardson; Dr. Craig McCormick
Kaposi’s sarcoma-associated herpesvirus (KSHV) is the etiologic agent of Kaposi’s sarcoma, primary effusion lymphoma, multicentric Castleman’s disease and KSHV-induced cytokine syndrome. KSHV follows a biphasic infectious cycle: upon infection it establishes latency with the genome maintained as an episome tethered to host chromatin, and cellular stress triggers expression of the replication and transcription activator RTA (ORF50) which initiates lytic replication, a program featuring heightened viral gene expression and genome replication. Lytic replication places a heavy burden on the endoplasmic reticulum (ER), the site of folding and modification of secreted and transmembrane proteins and activates the unfolded protein response (UPR). The UPR is coordinated by three ER-localized sensors, PERK, IRE1 and ATF6, which initiate complementary transcriptional programs that expand folding capacity and lipid synthesis, while PERK signaling attenuates cap-dependent translation and can trigger apoptosis if stress is unresolved. KSHV inhibits each arm of the UPR during lytic replication, but the viral factors and mechanisms responsible are incompletely understood. In this thesis I report that the early viral E3 ubiquitin ligase K3 directs K63-linked polyubiquitination of PERK, targeting PERK for lysosomal degradation and thereby terminating PERK signaling. ER stress enhanced K3-dependent PERK turnover, consistent with signal-dependent PERK degradation which converts PERK activation into PERK removal. I demonstrate that the viral G protein-coupled receptor vGPCR induces ER stress and potentiates K3-dependent PERK degradation, and that K3 reciprocally ubiquitinates vGPCR to promote its lysosomal clearance. Therefore, K3 regulates both a source of ER stress and the principal PERK-dependent response. Infection with a K3-deficient virus results in the dysregulated accumulation of viral proteins despite unchanged transcription, implicating K3 in post-transcriptional control of viral proteostasis. Subsequent ultrastructural and live-cell microscopy revealed extensive nuclear membrane remodeling during lytic replication in both WT and ∆K3 infections, pertaining to expansion of the Type-I nucleoplasmic reticulum. These invaginations serve as sites for primary envelopment and nuclear egress, and I document genetically and chemically labeled capsids traffic through these compartments into the cytosol. Together, these studies show that KSHV coordinates robust remodeling of ER and nuclear membranes to support productive infection, with K3 central to manage ER-stress and viral protein proteostasis.
Access status: Open Access ,
How Relational Continuity, Serious Mental Illness, and Substance Use Disorders Shape Management of Diabetes and Hypertension: Analysis of Population-Based Administrative Health Data in British Columbia
(2025-11-20) Poarch, Eric; Not Applicable; Master of Science; Department of Community Health & Epidemiology; Received; NA; Not Applicable; Dr. David Rudoler; Dr. Cindy Feng; Dr. Ruth Lavergne; Dr. Mark Asbridge
People with serious mental illness (SMI) and substance use disorders (SUD) are at higher risk of chronic physical diseases like diabetes and hypertension and related acute complications, but face barriers to chronic disease management (including longitudinal monitoring in primary care, medication management, and laboratory testing). It remains poorly understood how relational continuity and treatment for comorbid SMI and/or SUD shape recommended management of diabetes or hypertension. I used linked BC administrative health data from April 1, 2020 to March 31, 2023 to compare patterns of chronic disease management among patients with diabetes or hypertension treated for comorbid SMI/SUD using descriptive statistics (frequency, means, and standardized differences). Modified-Poisson regression models were used to calculate adjusted risk ratios between relational continuity and recommended management and included interaction terms to evaluate whether associations were modified by SMI/SUD treatment. Findings reveal disparities in chronic disease management among people treated for SMI and/or SUDs.
Access status: Embargo ,
Active Material Investigations in Lithium- and Sodium-Ion Batteries
(2025-11-18) Garayt, Matthew; Yes; Doctor of Philosophy; Department of Physics & Atmospheric Science; Not Applicable; Jean-Marie Tarascon; Not Applicable; Jeff Dahn; Theodore Monchesky; Michael Metzger
This thesis focuses on both methods to evaluate and produce new lithium- and sodium-ion battery active materials, as well as studying the use of new active materials. It focuses on the development and use of single-layer pouch cells, all-dry synthesis of mid-nickel positive electrode materials for lithium-ion batteries, and the development and use of lead-containing negative electrode materials for sodium-ion batteries. The first part of the thesis develops a method to make single-layer pouch cells and shows the benefits of this form factor. First, a comparison between single-layer pouch cells, coin cells, and stacked pouch cells is made, showing that when single-layer pouch cells are made without a negative electrode overhang, they give the best possible electrochemical performance. Finally, single-layer pouch cells are used in a case study comparing LFP and NMC full cells. The second part of the thesis develops an all-dry synthesis technique to make NMC640 in a water- and waste-free process. The all-dry synthesis consists of mixing transition metals and metal oxides with a lithium source and an optional tungsten coating in an auto grinder before calcination. The best all-dry synthesized materials with 0.3 mol% tungsten coating perform as well or better than a commercial NMC640 material in electrochemical half cell evaluations. The remaining parts of the thesis introduce lead as a promising sodium-ion negative electrode material. First, in half cell testing, it is found that lead negative electrodes with high active material loadings can cycle with no capacity loss when their electrodes contain single-walled carbon nanotubes and the electrolyte solvent is monoglyme. However, due to the large volume change of lead during sodiation, the lead particles break down into smaller particles and cause overall restructuring of the electrode. This repeated volume change also causes irreversible capacity loss in full cells. An initial attempt is made to make lead-carbon composite active materials that can mitigate the effects of the volume change. Overall, this thesis provides insights into new active materials, new methods to test them, and new production processes for them to produce lower cost and longer lifetime batteries.
Access status: Open Access ,
MICROGLIAL ACTIVATION IN THE CAT DORSAL LATERAL GENICULATE NUCLEUS FOLLOWING RETINAL INACTIVATION
(2025-11-18) Rizwan, Safiya; Not Applicable; Master of Science; Department of Clinical Vision Science; Received; Donald Mitchell; Not Applicable; Nadia Dicostanzo; Kevin Duffy
Amblyopia is the leading cause of monocular vision loss in children. Success in treating amblyopia using conventional methods such as patching and atropine penalization are hindered by compliance issues, rigid treatment schedules, and a short treatment window during young childhood. Thus, alternative treatments addressing these barriers are necessary to improve visual outcomes. Retinal silencing, by administering intravitreal injections of tetrodotoxin (TTX), is a potential treatment for amblyopia in lieu of patching or penalization. Fellow eye retinal silencing has shown good results in promoting visual recovery of the deprived eye, with no permanent detriment to the silenced eye. However, the underlying mechanisms that protect the eye during silencing are not fully understood. Microglia are a subtype of glial cells involved in mediating the development of the synaptic network in the central nervous system. The current study sought to determine if microglia are involved in a homeostatic response that protects the synaptic network against lowered neural activity elicited by retinal silencing. In other words, how are synapses-serving the inactivated eye protected from perturbation? Microglial activation was investigated as a possible protective mechanism by measuring ionized calcium binding adaptor molecule 1 (Iba1) immunolabeling within the silenced- eye layers of the dorsal lateral geniculate nucleus. The results of this study revealed that retinal silencing in young animals activates microglia, and that retinal silencing in older animals did not elicit such activation. These findings raise the possibility that activation of microglia mediates a homeostatic response to protect against retinal silencing-induced synaptic modifications. The current study also showed that retinal silencing in younger animals activates microglial transiently, as activation is not sustained following TTX with a period of binocular vision. As TTX treatment stands as a possible alternative treatment for human amblyopia, it is important to understand how TTX affects the synaptic network of the visual system.
Access status: Open Access ,
MECHANISMS DRIVING KELP DETRITAL PARTICULATE ORGANIC CARBON (POC) UNCERTAINTIES AND POPULATION DYNAMICS IN THE EASTERN SHORE ISLANDS, NOVA SCOTIA
(2025-11-12) Savard-Drouin, Alexis; Not Applicable; Master of Science; Department of Oceanography; Not Applicable; Ramon Filgueira; Not Applicable; Katja Fennel; Kira Krumhansl; Anna Metaxas
Kelps are large brown algae that sustain marine life, support fisheries, and provide valuable ecosystem services. Carbon cycling is an important ecosystem service for kelp forests as they are among the most productive and widespread coastal vegetated ecosystems globally. However, current detrital carbon production estimates from kelp forests carry large uncertainties and studies rarely offer tangible solutions to improve them. We addressed this gap by quantifying population dynamics and demographic rates for the two dominant kelp species in Nova Scotia, Laminaria digitata and Saccharina latissima and estimate the detrital carbon production of both species. These estimates account for kelp size, since larger individuals produce more detritus, and for seasonal patterns, as most detrital production occurs in autumn. We found that most of the uncertainty in detrital carbon production estimates stems from variability in kelp density and population size structure. Incorporating seasonally varying erosion rates also reduces uncertainty as annual averages tend to over-simplify temporal patterns. Carbon cycling in kelp forests may be at risk as populations in Nova Scotia have undergone cycles of decline and recovery, with recent decades marked by substantial losses. While the causes of decline, warming waters, increased storm frequency, grazing by mesograzers, and invasive species, are known to affect individual kelps, their effects on population-level processes remain less understood. We constructed matrix population models to investigate the life history mechanisms driving the population dynamics of both species. We found that small individuals are critical for long-term population persistence. L. digitata depends on the year-round survival of small individuals, while S. latissima relies on autumn spore release, winter recruitment, and spring growth of small individuals. Stressors disrupting these life history events such as warming, turf algal competition, impacts from the invasive bryozoan Membranipora membranacea, and the mesograzer snail Lacuna vincta are therefore likely to drive kelp population dynamics. We also found that large individuals are essential for short-term population persistence and recovery. Both warming and M. membranacea negatively affect juvenile life histories and reduce the presence of large adults. The loss of large adults also would negatively impact detrital carbon production from kelps. These stressors are synergistic as warming promotes the population growth of M. membranacea. Together, our findings provide a mechanistic understanding for how continued ocean warming may undermine both the ecosystem functions and population resilience of kelp forests in Nova Scotia.
Access status: Embargo ,
Utilizing Metabolomics and Genomics to Enhance Parasite Resistance in Sheep
(2025-11-06) Jawad, Hamza; Not Applicable; Master of Science; Faculty of Agriculture; Received; Dr. Luiz F. Brito; No; Dr. Younes Miar; Dr. John Gilleard; Dr. Ghader Manafiazar
Gastrointestinal parasites, particularly Haemonchus contortus, significantly compromise sheep farm profitability. We integrated metabolomics and genomics data from 78 Rideau Arcott ewe lambs during controlled infection to develop diagnostic and genetic tools for parasite management. Metabolomic analysis identified candidate biomarkers—including indole acetic acid and trans-hydroxyproline—that demonstrated the potential to detect subclinical infections with progressive diagnostic accuracy. After validation, these metabolites could enable earlier diagnosis and treatment in precision livestock systems. Whole-genome sequencing revealed copy number variation patterns associated with parasite resistance and susceptibility. We identified key genes influencing immune function and disease resistance, particularly CLCA1 duplication. These findings provide practical tools for integrated parasite management: metabolite candidate biomarkers can be incorporated into field-deployable point-of-care diagnostics for on-farm detection, while genomic markers enable genomic selection for parasite resistance in breeding programs. Implementation of these diagnostic and genetic tools will help the Canadian sheep industry reduce anthelmintic dependence while improving productivity.
Access status: Embargo ,
Investigation of Gas Evolution and Safety of Materials for Lithium and Sodium-Ion Batteries
(2025-10-30) Tulloch, Meredith; Not Applicable; Master of Applied Science; Department of Process Engineering and Applied Science; Not Applicable; n/a; Not Applicable; Jeff Dahn; Alison Scott; Michael Metzger
The increased use of rechargeable batteries is one strategy in the fight against climate change, as a higher battery usage allows for the integration of more renewable energy sources. However, the development of batteries, particularly sodium-ion batteries, is still underway, with improvements to energy density and lifetime as the main research goals. Changes to the cell chemistry, the use of electrolyte additives, alloying negative electrode materials, and increasing the upper cut-off voltage to achieve higher cell capacity are all viable options to improve cell performance. This work explores electrolyte additives and Pb as a negative electrode material in sodium ion cells through on-line electrochemical mass spectrometry to investigate how these components impact the gases that are produced during battery operation. The electrolyte additives sodium difluorophosphate and 1,3,2-dioxathiolane 2,2-dioxide were studied in comparison to a control electrolyte through half cell tests and storage tests with notable differences in the gases evolved. Pb was compared to hard carbon and a blended electrode containing both materials to study the differences in carbonate and ether based electrolytes. Lastly, accelerating rate calorimetry was used to characterize the safety limits of a layered oxide positive electrode material for lithium-ion cells. Various upper cut-off voltages were used to probe the safety limitations of the material. Further investigation into the thermal response of the layered oxide positive electrode was completed using x-ray diffraction analysis. Overall, this work provides results for the gases produced from various cell chemistries in sodium-ion batteries, as well as the thermal responses seen in lithium-ion positive electrodes.
Access status: Open Access ,
Integrating Hydrologic Climate Projections into Source Water Protection Planning in Small Atlantic Canadian Communities
(2025-10-30) Dort, Amber; Not Applicable; Master of Applied Science; Department of Civil and Resource Engineering; Not Applicable; n/a; Not Applicable; Graham Gagnon; Andrew Medeiros; Lauren Somers
Climate change is a critical driver of hydrologic change in Atlantic Canada, where small utilities often manage source water with limited capacity. This research supports small communities in assessing climate change impacts on water supplies and identifies efficient modelling approaches. Lake George, the water source for Yarmouth, Nova Scotia, served as the study site. The hydrological system was characterized using public data and field observations, followed by three modelling schemes of varying complexity to simulate lake water balance. Downscaled climate projections were applied to evaluate future impacts. Lake levels were most sensitive to summer precipitation, followed by temperature and usage. Complex models with site-specific hourly data outperformed the simpler daily model, projecting more extreme impacts, including levels dropping below an outlet but not the treatment intake. While complex models provide quantitative insight, simpler models can guide qualitative assessments. Findings informed Yarmouth's Source Water Protection Plan and can guide similar communities.
Access status: Open Access ,
Africville: Reparation in the Paradoxical Legal Construction and Deconstruction of an African Canadian Community
(2001-06) Sparks, Corrine E.; Not Applicable; Master of Laws; Faculty of Law; Not Applicable; unknown; Not Applicable; Philip V. Girard; Leon E. Trakman; Jennifer K. Bankier
This thesis examines the circumstances surrounding the relocation of the community of Africville with a view to reparations for the former Africville residents. There is a discussion of the theory of reparations. From a Critical Race perspective this thesis explores the historical significance of Africville in relation to other Black Nova Scotia communities. It also explores the involvement of Blacks in relation to the early colonial settlement of Nova Scotia. From personal interviews there is a documentation of the human toll which was paid by the former Africville residents when they were relocated in 1969. These anecdotal accounts also illustrate the inequities involved with the mass relocation of an entire community. There is also a brief comparison of redress for Japanese Canadians with a view to how Japanese Canadians were successful in obtaining redress for their years of suffering as a result of mass relocation and confiscation of their property in British Columbia in the 1940's during the Second World War. In order to further contextualize the historical experience of Nova Scotian Blacks, there is an examination of how the Black community has progressed since the Africville relocation. The social advocacy which was lacking during the Africville relocation has now developed with numerous professional associations which may be able to assist Africville residents as they seek redress. There is a review of two legal claims; unjust enrichment and unconscionability. Both of these equitable claims may prove helpful during litigation for the Africville residents. These two claims are based in equity and lend themselves to judicial discretion as well as principles developed through caselaw. Equitable remedies are also examined. These legal alternatives are discussed in light of two main jurisprudential theories; Legal Realism and Critical Race Theory. This discussion reveals the importance of jurisprudential approaches in the resolution of race based litigation. Finally, there are recommendations for how the Africville aftermath can be resolved so that the Black community can begin to heal in the face of horrendous racial injustice. If these measures are implemented, race relations could be greatly improved in the province of Nova Scotia.
Access status: Open Access ,
Can Video Games Improve Adherence to Treatment in Children with Chronic Diseases?
(2009-10) Kharrazi, Hadi Hadj Karim; Not Applicable; Doctor of Philosophy; Faculty of Computer Science; Received; A. Mokashi; Not Applicable; C. Watters; P. McGrath; A. Otley; M. Shepherd
This research explored the use of interactive information technology applications for children with long term treatment regimens in which adherence is a key factor in the success of the treatment. Behavior change models play a major role in enhancing adherence to treatment in patients with chronic conditions. In this research, a conceptual framework was designed based on the Theory of Planned Behavior. The conceptual framework was mapped to game enjoyment elements to develop a game framework. The framework learned from the patient's situation based on the patient's adherence rate and measured behavioral determinants; and then the game adapted itself to the new situation and created new strategies to empower the patient in order to reinforce positive intention and behavior on the part of the patient. The game framework was tested with children in two separate user studies including IBD (Inflammatory Bowel Disease) and Type I diabetes patients. Both user studies implemented a mixed between-group and within-subject methodology. Two versions of the game were developed, one with the embedded conceptual framework and another without. Participants were assigned randomly to the treatment and control groups. The treatment group played the game with the conceptual framework and the control group played the game without the theoretical framework. In the middle of the study, each group switched to the other game type and experienced a within-subject change. The results were analyzed by GLM-ANOV A and Mix-Modeling. GLM-ANOV A showed a significant effect of game type (conceptual framework) on both behavioral intention and adherence to treatment regimens in patients with Inflammatory Bowel Disease and patients with Type I diabetes. Mix-modeling showed a significant effect of game type, time and the interaction between them on both behavioral intention and adherence to treatment regimens in both user studies.
Access status: Embargo ,
SoftAdaClip: A Smooth Clipping Strategy for Fair and Private Model Training
(2025-10-27) Soleymani, Dorsa; Not Applicable; Master of Computer Science; Faculty of Computer Science; Not Applicable; n/a; Not Applicable; Dr. Vlado Keselj; Dr. Sageev Oore; Dr. Frank Rudzicz
Differential privacy (DP) provides strong protection for sensitive data, but often reduces model performance and fairness, especially for underrepresented groups. One major reason is gradient clipping in DP-SGD, which can disproportionately suppress learning signals for minority subpopulations. Although adaptive clipping can enhance utility, it still relies on uniform hard clipping, which may restrict fairness. To address this, we introduce SoftAdaClip, a differentially private training method that replaces hard clipping with a smooth, tanh-based transformation to preserve relative gradient magnitudes while bounding sensitivity. We evaluate SoftAdaClip on various datasets, including MIMIC-III (clinical text), GOSSIS-eICU (structured healthcare), and Adult Income (tabular data). Our results show that SoftAdaClip reduces subgroup disparities by up to 87% compared to DP-SGD and up to 48% compared to Adaptive-DPSGD, and these reductions in subgroup disparities are statistically significant. These findings underscore the importance of integrating smooth transformations with adaptive mechanisms to achieve fair and private model training.
Access status: Open Access ,
Healthy Sleep for Healthy Schools: Evaluating the Usability, Effectiveness, and Implementation Potential of a School-based Sleep Education Program
(2025-08-19) Rosenberg, Lindsay; Not Applicable; Doctor of Philosophy; Department of Psychology and Neuroscience; Received; Dr. Joseph Buckhalt; Not Applicable; Dr. Gabrielle Rigney; Dr. Alissa Pencer; Dr. Penny Corkum; Dr. Penny Corkum
Adolescence is a critical time of development; however, many adolescents are not obtaining sufficient sleep, an influential factor in well-being. There are few accessible evidence-based sleep-education programs, leading to an “evidence-to-practice gap.”Schools are an optimal environment to teach sleep education, as this allows for many adolescents to learn about healthy sleep, in a place that is easily accessible to them. This dissertation evaluates the usability, effectiveness, and implementation potential of a school-based sleep education program, Healthy Sleep for Healthy Schools. A usability study (Study 1; n = 8) gathered quantitative and qualitative feedback from teachers based on Morville and Sullenger’s User Experience Honeycomb framework (2010). Quantitative feedback was neutral to positive, suggesting teachers found the program useful, useable, findable, desirable, accessible, credible, and valuable. Qualitative feedback was mostly positive, with constructive feedback regarding program length, scheduling challenges, and interactivity of student content. HS4HS was evaluated for effectiveness with students (Study 2; n = 203), using a pre/post design. The study assessed insomnia symptoms, sleep habits, daytime sleepiness, knowledge about sleep, attitudes and beliefs about sleep, and psychosocial functioning. Findings demonstrated improvements in insomnia symptoms for students with subthreshold to severe insomnia, however no improvements were made for the overall sample. Qualitative feedback on program satisfaction suggested that students learned about sleep and how to improve sleep habits, with students suggesting modifications to improve engagement, delivery time, that the program should not replace physical education, and the study measures were burdensome. The third study examined the implementation potential of the HS4HS program (Study 3; n = 12). Semi-structured interviews were conducted with teachers and school stakeholders based on the RE-AIM implementation framework (Glasgow et al.,1999), to evaluate the reach, effectiveness, adoption, implementation, and maintenance of the HS4HS program. Feedback suggested aligning with the curriculum, and fostering buy-in and engagement. This dissertation research was undertaken to better understand the program and to make modifications based on end-user data. Further effectiveness testing will be conducted upon program modification, with the goal of eventually helping to close the “evidence-to-practice” gap and thereby improve adolescent health.
Access status: Open Access ,
RETHINKING THE LEGAL ARCHITECTURAL FRAMEWORK OF THE INTERNATIONAL CLIMATE REGIME: AN EVALUATION OF THE COMPLIANCE MECHANISM WITHIN THE PARIS AGREEMENT
(2025-10-20) AMAYE, ABIMBOLA; Not Applicable; Master of Laws; Faculty of Law; Not Applicable; Professor Sara Seck; Not Applicable; Professor Robert Currie; Professor Patricia Galvao-Ferreira
The Paris Agreement is a significant change in international environmental law that prioritises three important factors: transparency, inclusion, and iterative ambition, whereas previous frameworks depended on harsh penalties and top-down enforcement. This thesis studied the Agreement’s compliance mechanism (Articles 4, 13, and 15) to determine whether a facilitative approach can be a successful international legal response to the climate catastrophe. Using a mixed-methods approach (doctrinal legal, comparative legal, and qualitative content analysis), this involved contrasting the Paris model with earlier international environmental law regimes, illustrating a transition from coercive enforcement to facilitative compliance. The results showed that three crucial elements are necessary for the Paris Agreement to be effective: transparency, reputational pressure, and iterative improvement through the use of tools like the Global Stocktake and the Enhanced Transparency Framework. Broader participation is made possible by the Paris Accord's soft law mechanisms, such as nationally specified contributions, which encourage gradual norm internalisation. Article 15's non-punitive design demonstrates political pragmatism by striking a balance between openness and ambition and ensuring almost universal participation. The research suggests that hybrid models, which combine facilitative tools with selective harder elements like graduated review mechanisms, offer the most promising way forward despite practical challenges like those associated with voluntary reporting. The Paris Agreement's Implementation and Compliance Committee's effectiveness should be further examined, with comparative studies across other international regimes potentially testing the effectiveness of hybrid compliance models.

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