Faculty of Graduate Studies Online Theses

Permanent URI for this collectionhttps://hdl.handle.net/10222/11163

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Open Access
Sexuality, Intimacy, and Speech-Language Pathology: A survey of clinicians’ knowledge, comfort, attitudes, and practices
(2025-04-01) Day, Francis; Not Applicable; Master of Science; School of Communication Sciences and Disorders; Received; n/a; Not Applicable; Dr. Rebecca Affoo; Mr. Glen Nowell; Dr. Ellen Hickey
Communication (speech, language, cognitive) and swallowing disabilities have been shown to have an impact on sexuality and intimacy in a variety of populations. Augmentative-Alternative Communication (AAC) users reported impacts on their sexuality and intimacy as well. Previous research suggests speech-language pathology may have a role in addressing sexuality when it is impacted by communication and swallowing disorders. This thesis aims to investigate the current state of practice of speech-language pathologists (SLPs) in Canada regarding addressing sexuality and intimacy, barriers to doing so, and their knowledge, comfort, and attitudes. A survey with a mix of 26 closed-ended and 4 open-ended questions was distributed to 1,149 SLPs; 56 met the inclusion criteria and completed the survey. The results show SLPs in Canada are addressing sexuality and intimacy to some extent, although most do not have a specific strategy to do so. Barriers to treating sexuality and intimacy appear to primarily be the lack of knowledge and training. In general, SLPs are unsatisfied with their knowledge regarding sexuality and intimacy, particularly around its relationship to disability and the ethics of treating sexuality and intimacy. Other significant barriers include uncertainty with their scope and practice guidelines, as well as discomfort with treating sexuality and intimacy. These findings are largely consistent with findings of research in other healthcare fields. Solutions may be found in examples from other professions. Future research should further investigate and promote the roles of SLPs in addressing sexuality and intimacy, and continue examining personal and environmental factors, as well as adaptations for youth.
Open Access
SEMANTIC BRIDGE: A MODEL FOR SEMANTIC WEB LITERATURE-BASED DISCOVERIES
(2025-03-31) Di Matteo, Nicola Raffaele; Not Applicable; Doctor of Philosophy; Faculty of Computer Science; Not Applicable; Leslie Carr; Not Applicable; Evangelos Milios; Eric Poitras; Jamie Blustein
Literature-based discovery focuses on retrieving hypotheses from apparently unrelated scientific papers. Studies show that joining facts from different documents can suggest unpublished hypotheses, potentially leading to significant discoveries. With over fifty million papers published and the significant benefits to humanity that discoveries bring, succeeding in automatically generating new hypotheses from the scientific literature is both challenging and crucial. At this stage, a collective effort and a strong collaboration of technical and domain experts of different disciplines are required. The best system can be built with technologies that standardize knowledge sharing and reasoning by combining published data, like those offered by the Semantic Web mechanisms. Surprisingly, existing systems proposed for making discoveries overlook these tools and neither provide means to include other tools to resolve a specific part of the problem. Thus, they require considerable effort to build from the ground up, which confines them to merely interesting projects that are eventually abandoned. One reason for not adopting Semantic Web technologies could be the previously scarce availability of essential data resources, a situation that has changed rapidly. Literature-based discovery systems based on Semantic Web technologies can now be built; the possibility of having a system to make discoveries where researchers, practitioners, and experts of different disciplines collaborate to create its building blocks is concrete. With my thesis, I propose a model that uses Semantic Web technologies to facilitate the development of collaborative, expandable, and reusable discovery systems. A proof-of-concept will be presented, demonstrating the integration of natural language processing, efficient reasoning, and innovative result presentation methods. This system will highlight the effectiveness of publishing scientific assertions with nanopublications, preserving provenance and intellectual property, suggesting a new way to publish papers, and the emergence of a Web of scientific facts for which the study aims to lay the foundation.
Open Access
Chinese Consumers’ Perceptions, Attitude, and Purchase Intention of Organic Products
(2025-03-28) Liu, Yining; Not Applicable; Master of Science; Faculty of Agriculture; Received; Dr. Hélène Deval; Not Applicable; Dr. Gumataw Abebe; Dr. Andrew Hammermeister; Dr. Christopher Hartt; Dr. Ji Lu
This research studied the psychological mechanisms influencing Chinese urban consumers’ organic food purchases. Surveying over 1,500 participants from Beijing, Shanghai, and Chongqing, it identifies key predictors using regressions, MANOVAs, neural networks, and SEM. Findings show that perceptions of nutritional content drive purchase intention, while affordability predicts behaviour. Attitudes toward utilitarian and hedonic benefits directly influence intention; ethical attitudes have an indirect effect. The study offers practical and theoretical insights for promoting organic food in China.
Open Access
Transcultural Approaches to Weather, Water, Ice, and Climate Research in Nunatsiavut
(2025-03-28) Bishop, Breanna; No; Doctor of Philosophy; Interdisciplinary PhD Programme; Received; Dr. Henry Huntington; Yes; Dr. Melanie Zurba; Dr. Gita Ljubicic; Dr. Eric C.J. Oliver; Dr. Claudio Aporta
Globally, there have been increasing calls for environmental research and governance to be led by Indigenous groups, be inclusive of Indigenous Knowledge, and support Indigenous self-determination. This is being advanced in weather, water, ice, and climate (WWIC) research throughout Inuit Nunaat – Inuit circumpolar homelands – where climate change is having cascading effects on WWIC conditions, the timing and distribution of species, and the ability for Inuit to safely travel and successfully harvest year-round on the land, water, and ice. It is important to understand how Inuit Knowledge and Western science can be brought together to advance WWIC research with and for Inuit. This dissertation provides critical insights on participatory research approaches that can be used to co-develop boundary objects (research constructs) that support and enable transcultural WWIC research and generate outputs that align with Inuit experiences of their environment.
Open Access
COASTAL FLOODING, EROSION, AND SEA-LEVEL RISE THREATEN SMALL-ISLAND GROUNDWATER RESOURCES IN A CHANGING CLIMATE
(2025-03-28) Cantelon, Julia; Yes; Doctor of Philosophy; Department of Civil and Resource Engineering; Not Applicable; Dr. Audrey Sawyer; Yes; Dr. Craig Lake; Dr. Scott Ketcheson; Dr. Barret Kurylyk
Dense human populations and productive ecosystems on small islands disproportionately rely on groundwater to meet their freshwater needs because fresh surface water is limited. The ocean controls groundwater level and salinity dynamics via an ocean-aquifer hydraulic connection, and saltwater intrusion (SWI) from seawater flooding and sea-level rise (SLR) will increasingly threaten potable groundwater in a changing climate. Thus, understanding SWI processes is critical to evaluate fresh groundwater vulnerability. This dissertation reviews SWI from seawater flooding to identify knowledge gaps and management challenges. Few studies have characterized complex SWI processes over multiple timescales or their feedbacks with coastal zone dynamics. Using field data and numerical models, subsequent chapters of this dissertation investigate knowledge gaps related to island groundwater dynamics and salinization over multiple timescales in response to oceanic, morphologic, hydrologic, and climatic drivers. Monitoring of Hog Island, Prince Edward Island and Sable Island, Nova Scotia, captures morphologic change with drone-based LiDAR and groundwater level and salinity dynamics with electromagnetic geophysics and monitoring wells. Data from four major hurricanes reveals that groundwater levels recover quickly, but salinization is persistent as flood effects outpace freshening from meteoric recharge. Data from Hog Island, demonstrate that rapid erosion during seawater flooding increases SWI and shifts coastal boundaries inland such that flooding from frequent smaller events (tides and seasonal waves) prolongs recovery. Comparing new data to historical data from the 1970s on Sable Island shows a feedback between frequent and rapid seawater flooding, erosion, and SWI events that drive long-term fresh groundwater loss that lags long-term morphologic change. Simulations of groundwater levels, pond areas, and SWI on Sable Island during a seawater flood and projected SLR reveal SWI along the coast, but a paradoxical increase in inland fresh surface water via groundwater rise and pond expansion. These studies provide new insights into the spatiotemporal dynamics of island freshwater resources and demonstrate the importance of understanding multi-temporal interconnections between coastal flooding/SLR, morphodynamics, SWI, and groundwater-surface water exchanges to address coastal groundwater vulnerability in a changing climate.
Embargo
Quantifying bias in underwater radiated noise measurement
(2025-02-14) Dupuis, Jasper; Not Applicable; Master of Applied Science; Department of Electrical & Computer Engineering; Not Applicable; n/a; Not Applicable; Sageev Oore; Sergey Ponomarenko; Mae Seto
The measurement of ship underwater radiated noise (URN) is a foundational element of underwater noise management policies. These measurements are frequently made in shallow water (<50 m). Current methods estimate the power spectrum with a single transmission loss applied for all frequencies. A latent assumption in this is signal stationarity, i.e., propagation loss properties do not change with ship position relative to the hydrophone. A breach of the stationarity assumption leads to bias in calculating the average. Using this work's proposed methodology, the stationarity assumption is shown to be false in the along-track dimension for one ship at one site at two different times of the year, from 30 to 300 Hz. This band covers many noise sources of interest on ships. Linear regression methods demonstrate some violations of stationarity but produce smaller estimates of bias. Single layer neural networks are shown to produce higher levels of estimated bias but only marginally better mean absolute error and root mean squared error statistics for an ideal ship model. When neural networks models are applied back to the original run data, it is found the magnitude of real bias lies between that of the regression models and the ideal ship model.
Open Access
Intersections of Social Circus and Social Work: A Critical and Embodied Analysis
(2025-03-15) Kitz, A.; Not Applicable; Master of Social Work; School of Social Work; Not Applicable; N/A; Not Applicable; Dr. Niki Kiepek; Dr. Marion Brown; Dr. Catherine Bryan
Social circus is a term generally accepted to refer to a form of social intervention using circus arts. This thesis examines the intersection of social work and social circus, and the social /political benefit of bringing together anti-oppressive social work practice with social circus for the purposes of self-improvement and community consciousness-raising. The project deploys critical social work theory—notably queer and disabilities theories—to analyze, critique, and disrupt social circus’s ableist and colonial features, by asking what a critically-oriented social circus as a space for all people to create art and share their stories might look like. Methods include two analytic processes: a critical review of the current literature on social circus and an embodied circus practice. Findings mirror tensions between critical and mainstream approaches to both practices. The project shares insights for critical social work and emphasizes the importance of reframing as a pathway of resistance against oppression.
Open Access
Exploring Open-Ended Creative Coding Assignments in Introductory Computer Programming
(2025-03-27) Crane, Brent; Not Applicable; Master of Computer Science; Faculty of Computer Science; Received; n/a; No; Hanieh Shakeri; Lizbeth Escobedo Bravo; Eric Poitras
Creativity is a key element in computer science education, as it helps engage students through problem-solving. This study examines how open-ended versus guided assignments impact creativity and performance in an introductory programming course. The assignment formats were counterbalanced across course sections, and students chose the format for the third assignment. After each assignment, students completed surveys to assess their motivation and emotions. Results show that the assignment format did not affect performance. However, the open-ended game development assignment fostered creativity and was linked to reduced negative emotions, along with increased positive emotions and self-efficacy. This research contributes to the limited literature on creativity in computing education and the design of open-ended assignments.
Open Access
Evaluating Data Quality of Coastal Spectrophotometric pH Measurements: Implications for Ocean Acidification and Ocean Alkalinity Enhancement Research
(2025-03-23) Fradette, Caroline; Not Applicable; Master of Science; Department of Oceanography; Not Applicable; n/a; Not Applicable; Dr. Katja Fennel; Dr. Michael Dowd; Dr. Douglas Wallace
pH, which reflects the thermodynamic balance of acid-base systems in seawater, serves as a key indicator of the interplay between acidic and basic components in marine environments. When combined with another parameter, such as TA, DIC, or pCO2 the entire inorganic carbon system can be derived. However, each parameter presents methodological challenges that may introduce random or systematic errors, which then propagate through subsequent calculations. In coastal and estuarine environments, errors can become more pronounced, as standard operating procedures (SOPs) developed for open-ocean conditions may not adequately address the complexities unique to these regions. Measuring more than two parameters enables further insight into systematic errors through the evaluation of internal consistency, where existing data products often reveal pH-dependent offsets between measured pH and pH calculated from measured TA and DIC. These offsets may arise from errors in pH measurements, TA and DIC measurements, or the equilibrium constants used in the calculations, and are therefore difficult to tease apart. Comparing measurements from different research groups can help identify the specific measurement biases responsible for these offsets; however, the lack of inter-comparison studies, particularly in field settings, hinders our understanding. This work advocates for integrating internal consistency and inter-comparison studies in field conditions, as conducting them at sea provides a realistic evaluation of reproducibility between research groups. Chapter 2 utilizes this method by comparing at-sea spectrophotometric pH (pHspec) measurements from two research groups aboard the R/V Coriolis in June 2022 in the Gulf of St. Lawrence and the Lower St. Lawrence Estuary during the Tracer Release Deep Experiment 2 (TReX2) cruise. This combined analysis of reproducibility and internal consistency highlights how even minor methodological differences can substantially affect data quality, and in turn, shape data interpretation. These impacts are particularly pronounced when estimating potential bias from unidentified, excess components of TA (TAx), expected to be non-negligible in estuarine environments, where the two groups had notably different estimates. Chapter 3 draws conclusions from the discussion of data quality in estuarine environments from Chapter 2, focusing on the potential role of pHspec in Monitoring, Reporting, and Verification (MRV) frameworks for ocean alkalinity enhancement (OAE), a proposed marine carbon dioxide removal (mCDR) strategy. It incorporates insights from OAE field trial work in the Bedford Basin, Halifax, a fjord-like estuarine system, to assess the quality of pHspec, TA, and DIC data, offering an assessment of the reliability of these measurements for interpreting potential carbon dioxide removal. This chapter also includes suggestions for a future protocol for observational components of MRV frameworks.
Open Access
Exploring the vertical distribution of redox-sensitive elements in a coastal anoxic basin, Whycocomagh Bay, NS
(2025-03-25) Chambers, Teala; Not Applicable; Master of Science; Department of Oceanography; Not Applicable; Dr. Carolyn Buchwald; Not Applicable; Dr. Christopher Algar; Dr. Douglas Wallace; Dr. Bruce Hatcher
Oceanic dissolved oxygen has been decreasing in concentration due to climate change, and this is expressed most strongly coastal waters. Whycocomagh Bay (Bras d’Or Lake, Cape Breton, Nova Scotia) has a deep basin that has been reported to be anoxic below 20m depth (to the seabed at 48m) for at least half a century. It provides an accessible site where anoxic biogeochemical processes can be studied repeatedly. Water sampling was achieved using a prototype syringe sampler, and vertical profiles of several redox-sensitive elements are presented and analyzed, some which have not been measured previously in the Bras d’Or Lake. These profiles are focused in the anoxic basin, but other sites within and outside of Whycocomagh Bay are included for reference. These profiles reveal chemical gradients that inform hypotheses about causal processes and effects of anoxia and hypoxia, which may be tested with the continued use of the techniques developed here.
Embargo
More than a Mesh: Encoding Metadata in the Lower Positional Bits of Polygonal Models
(2025-03-21) Lee, Ben; Not Applicable; Master of Computer Science; Faculty of Computer Science; Not Applicable; n/a; Not Applicable; Derek Reilly; Dirk Arnold; Stephen Brooks
Vertices in 3D meshes are typically stored with more precision than is needed for many applications. In this thesis we present a method to use this surplus of precision to store additional metadata in the mesh and connect to a variety of online and offline applications, all while still being able to use the mesh as-is in the graphics pipeline. We apply this method to five different use cases. We show that we can store ambient occlusion to a level which is imperceptible to its vertex coloured equivalent. We further describe a method to link to online services through an encoded URL, and introduce our machine learning based subdivision surface approach which uses the extra precision to store user driven adjustments. We then describe a method to store an embedding that can be used to retrieve similar meshes from an online database. The final example is a method to store information to create a prefractured version of the mesh.
Embargo
INVESTIGATION OF THE NOVEL INTERACTION BETWEEN THE HUMAN RECEPTOR FOR ACTIVATED C KINASE 1 (RACK1) AND 26S PROTEASOME
(2025-03-21) Shi, Yunnuo; Not Applicable; Doctor of Philosophy; Department of Microbiology & Immunology; Not Applicable; Stanley Moore; Not Applicable; Jeanettee Boudreau; David Langelaan; Craig McCormick; Zhenyu Cheng
The 26S proteasome is a highly conserved protein degradation complex. It facilitates ATP- and ubiquitin-dependent protein degradation and plays a central role in the ubiquitin-proteasome system (UPS). The proper function of the proteasome is essential for maintaining protein homeostasis by removing damaged and misfolded proteins as well as regulating protein turnover under various physiological and pathological conditions. RACK1, a highly conserved WD40 repeats scaffolding protein, is known for its ability to coordinate diverse protein-protein interactions. RACK1 is involved in the protein homeostasis network by serving as a platform for recruiting protein substrate or co-factors, as well as organizing protein complexes formation. Interestingly, RACK1’s involvement in the regulation of proteasome function has not been thoroughly explored. This study identified a novel interaction between RACK1 and the proteasome, shedding light on RACK1’s potential role in regulating proteasome activity. RACK1 was found to directly interact with 26S proteasome preferentially with 19S regulatory proteasome subcomplex through the N-terminal three WD repeat. RACK1 selectively enhances the proteasome’s trypsin-like activity in a purified protein system without affecting other catalytic activities. In the cellular context, RACK1 was shown to play a role in maintaining basal proteasome gene expression independently of NRF1 and NRF2 activation, the master transcription factors regulating proteasome genes. Furthermore, RACK1 was found to mitigate stress-induced NRF2 and proteasome gene expression, potentially through its role in maintaining proteasome activity and mitigating oxidative stress. These findings provide valuable insights into the regulatory interplay between RACK1 and the proteasome. In summary, this study establishes RACK1 as a novel and multifaceted regulator of proteasome activity, participating in both direct modulation and transcriptional regulation of proteasome function. These findings expand our understanding of the mechanisms governing proteasome function and highlight the potential of RACK1 as a therapeutic target in diseases associated with proteasome dysfunction and impaired protein homeostasis.
Open Access
The impact of the Canadian emergency response benefit during the COVID-19 pandemic on the prevalence of household food insecurity in Canada
(2025-03-12) Jimenez, Laura; Not Applicable; Master of Science; Department of Community Health & Epidemiology; Not Applicable; n/a; Not Applicable; Sanja Stanojevic; Leah Cahill; Daniel Dutton
Background: During the COVID-19 pandemic, the Canada Emergency Response Benefit (CERB) was introduced to mitigate the impact of sudden mass unemployment. To date, no study has examined the association of CERB and the prevalence of food insecurity (FI). Objectives: To determine if the introduction of CERB reduced the prevalence of FI in Canada using a difference-in-differences (DID) analysis of Canadian Income Survey (CIS) data, and subgroups of interest: female-led lone parent households and households living in poverty. Methods: CIS cycles 2018-2020 linked to CERB (weighted n=27,535,068) were used. A DID analysis estimated the association between CERB receipt and the log odds of FI. Results: Levels of FI were maintained in CERB-recipient households and decreased in non-CERB recipients. CERB receipt modified the relationship with FI between CERB and non-CERB households (0.145, p= 0.034). Conclusion: This study shows that despite mass unemployment, no increases occurred in FI among unemployed CERB recipient households.
Open Access
PIDNET-SLAM: A MULTI-RESOLUTION SEMANTIC SLAM ALGORITHM FOR DYNAMIC SCENES
(2025-03-16) Rajan, Siddharth; Yes; Master of Applied Science; Department of Electrical & Computer Engineering; Not Applicable; n/a; Not Applicable; Dr. Mae Seto; Dr. Kamal El-Sankary; Dr. Jason Gu
Simultaneous Localization and Mapping (SLAM) enables robots to map their surroundings while determining their positions in real time. Traditional SLAM systems typically assume static environments, causing accuracy issues when dynamic objects are present. Existing methods, which often use deep learning techniques like semantic segmentation, instance segmentation, and object detection, increase accuracy but add significant computational overhead, making them unsuitable for real time use. Therefore, a robust and computationally efficient SLAM solution capable of effectively handling dynamic scenes is needed. To address these challenges, we introduce PIDNet SLAM, an innovative extension of ORB SLAM 3 that effectively manages dynamic environments. PIDNet SLAM incorporates a multi resolution semantic segmentation network based on PIDNet, consisting of two parallel branches: a low resolution branch actively processing non keyframes, and a high resolution branch providing supplementary high resolution features without interfering with the main workflow. Additionally, a lightweight geometric module uses geometric transformations and optical flow to identify and eliminate dynamic features, enhancing the system’s overall accuracy. Evaluations on the dynamic TUMM RGB-D dataset show PIDNet SLAM significantly outperforming existing methods like Dyna SLAM, SOLO SLAM, and ORB SLAM 3, achieving over 97% improvement in localization accuracy in dynamic scenarios. Remarkably, the system maintains an average processing time of only 49ms per frame on a low power GPU, demonstrating an optimal balance between accuracy and computational efficiency. PIDNet SLAM thus presents a critical advancement toward effective real time SLAM in dynamic environments, with potential future improvements focusing on refining the low resolution branch for even faster performance.
Open Access
Mapping the Complex Patterns of Degradation in Commercial Lithium-Ion Batteries Using X-Ray Imaging and Diffraction
(2025-03-13) Bond, Toby; Not Applicable; Doctor of Philosophy; Department of Physics & Atmospheric Science; Not Applicable; Jay Whitacre; Yes; Theodore Monchesky; Michael Metzger; Jeff Dahn
Understanding and mitigating degradation in Li-ion batteries is a major area of focus in the electric vehicle industry. Studying battery degradation often requires long-term cycling experiments, which are best done with machine-made cells using commercial form factors to accurately represent real- world operating conditions. In this thesis, we use synchrotron-based X-ray imaging and diffraction to comprehensively study the structural and functional changes that occur in commercial cells after thousands of cycles. This work explores multi-scale effects that have not previously been observed and fills the gap between nano-scale and macro-scale in-situ imaging that exists in the literature. Time-resolved, operando experiments capture the kinetic effects of degradation and reveal their complex, spatially heterogeneous nature. The use of commercial-form- factor cells in this work also provides new insights into how cell geometry, operating conditions, and even gravity can significantly influence the patterns of degradation that form after extended cycling.
Open Access
Activity Adjustment in Response to Chronic Back Pain
(1994-09) Archibald, Elizabeth Jean; Not Applicable; Master of Arts; School of Health & Human Performance; Not Applicable; unknown; Not Applicable; Phil Compagna; Geraldine Hart; Cheryl Kozey; Rene Lyons
The purpose of this qualitative research study was to explore work and leisure adjustment in nurses with a chronic work-related back injury. A face-to-face individual interview was conducted with ten female nurses, aged 35-49 years, recruited from a pain clinic. The acquisition of a disability due to an occupational accident not only resulted in a loss of earnings, but also generated a complete set of adaptive tasks for the nurse and her family. The themes that emerged from content analysis of interviews with ten nurses included the need for constant adaptation in daily routines, the need for instrumental and emotional support, specific role adaptations, leisure participation, and involvement in the Workers' Compensation system. Work and leisure adjustment was an added adaptive task that determined an individual's adjustment outcome. Future research and services should attend to adjustment styles in work and leisure.
Open Access
Coping Strategies, Burnout, and Intent to Leave Among Critical Care Nurses
(1991-09) Lauzon, Laurie Marie; Not Applicable; Master of Nursing; School of Nursing; Not Applicable; unknown; Not Applicable; Brian Eastwood; Florence Myrick; Judith Ritchie
There has been a great deal of research interest devoted to the stressful situations encountered in critical care nursing, but few attempts to explore the relationships between individual responses to stressful situations and outcome variables. Guided by the framework of stress and coping proposed by Lazarus and Folkman (1984), this study examined the relationship between the coping behaviours critical care nurses used to manage a hypothetical stressful situation and outcomes, including burnout and intent to leave. Self-report data were collected from 173 critical care nurses from three agencies in Atlantic Canada. Instruments used to measure the study variables included: the Ways of Coping Questionnaire (Lazarus & Folkman, 1984), the Maslach Burnout Inventory (Maslach & Jackson, 1986), and a single item measure of intent to leave. A variety of descriptive and inferential statistics were used to explore the relationships between the study variables. The most frequently used coping strategies were planful problem-solving, self-controlling, and seeking social support. Only one of the eight methods of coping measured, planful problem-solving, was significantly related to tenure in critical care nursing. The findings demonstrated a significant relationship between the nurses choice of coping strategies and burnout. Escape/avoidance and confrontive coping were predictive of burnout. Planful problem-solving and positive reappraisal were negatively related to burnout. Burnout was also predictive of the nurses' intent to leave their current positions. The findings suggest that both personal and situational factors, as well as individual responses to stressful situations have an impact on the turnover of nursing staff in critical care units.
Open Access
Offshore Wind Energy in Canada: Charting an Ecologically Sustainable Future from International Law and Policy Coordinates and State Practices
(2025-03-05) Alikhani, Mohamad; Not Applicable; Doctor of Philosophy; Faculty of Law; Not Applicable; Jeremy Firestone; Not Applicable; Phillip Saunders; Patricia Galvao Ferreira; David VanderZwaag
This thesis addresses a critical issue: while offshore wind energy (OWE) reduces greenhouse gas emissions and helps Canada meet its climate goals under the Paris Agreement, it may also harm marine ecosystems, potentially conflicting with biodiversity conservation efforts. OWE can lead to the loss of fish and fish habitats as a result of construction activities, as well as bird and bat mortality due to turbine collisions. Utilizing ecological sustainability as a theoretical framework, the thesis examines how Canada can enhance its regulatory framework for OWE to protect biodiversity. It recommends: (i) broadening ecological sustainability in the law; (ii) implementing integrated management through legally binding marine spatial planning; and (iii) employing strategic and environmental assessments to mitigate the adverse impacts of OWE. It analyzes key federal laws and provincial laws of Nova Scotia and proposes strengthening various Acts to support an ecologically sustainable future for OWE in Canada.
Open Access
DISCOVERING BLUE TEAM SOLUTIONS FOR AN AUTONOMOUS CYBER OPERATIONS CHALLENGE USING AN EVOLUTIONARY HEURISTIC SEARCH
(2025-03-03) Wang, Yuxuan; Not Applicable; Master of Computer Science; Faculty of Computer Science; Not Applicable; n/a; Not Applicable; Dr. Nur Zincir-Heywood; Dr. Khurram Aziz; Dr. Malcolm Heywood
In this thesis, a novel machine learning-based approach to autonomous network defence is introduced. The approach utilises an evolutionary strategy to optimise heuristic blue team agents. One approach typically assumed for approaching this problem would deploy a (complex) neural network to discover an appropriate blue agent policy through reinforcement learning against a ‘red’ team on a simulated network environment. Conversely, in this work, we use blue team knowledge regarding network topology and possible attack vectors to define a default defensive heuristic. In common with neural solutions, a preprocessed observation space is assumed in which ‘host scan state’ is expressed. However, we categorised actions in the action space to impose a structured action selection strategy, enabling a defensive efficiency to be maximized using an evolutionary strategy, i.e. a form of Steepest Assent Hill Climbing. Our approach was benchmarked using a simulated network environment with three subnets and diverse adversaries called TTCP CAGE Challenge 2. The CAGE Challenge 2 task defines two types of attacking agents: b_line and meander. We demonstrate that the red b_line agent was countered through a strategy that prioritized the defence of critical hosts. Defending against the adaptive red meander agent required a tiered strategy treating hosts with varying importance levels. Our model achieved second place on the official ranking board (consisting of 16 solutions based on different deep learning frameworks) and surpassed the champion team while performing testing on an updated simulation engine. These results show the potential of evolutionary strategies for advancing AI-driven cyber defence. Specifically, we develop valuable insights into how researchers in the field can utilize knowledge about task representation for discovering efficient solutions for cyber-defence.
Open Access
BEFORE AND AFTER-SCHOOL PROGRAM STAFF PERCEPTIONS OF RISK IN AN OUTDOOR LOOSE PARTS PLAY INTERVENTION
(2025-02-27) MacDonald, Ainsley; Not Applicable; Master of Arts; School of Health & Human Performance; Not Applicable; Dr. Sherry Huybers; Not Applicable; Dr. Michelle Stone; Dr. Laurene Rehman; Dr. Becky Feicht
Introduction: Outdoor play is essential for children's development and well-being, yet opportunities for risky outdoor play in structured settings remain limited. This study examines a health promotion perspective on a loose parts play (LPP) intervention and program staff perceptions of risky outdoor play in before- and after-school programs. Purpose: The purpose of this qualitative descriptive study was to explore program staff perspectives regarding risky play in the context of an outdoor loose parts play intervention in before and after-school settings. I investigated two research objectives: (1) To explore how program staff conceptualized and understood risky outdoor play and (2) To explore and understand what factors influence program staff's perceptions of risky outdoor play. Methods: Grounded in a constructivist worldview, this study employed Reflexive Thematic Analysis (RTA) to analyze qualitative data from focus groups conducted before and after the intervention. The intervention introduced loose parts into outdoor play areas and gathered staff perspectives to assess its impact. My positionality and reflexivity as the researcher were integral throughout the research process. Findings: I developed three themes from the analysis: (1) Loose Parts Play as a Stepping Stone for Risky Outdoor Play, (2) Braving the Unknown: Risk as a Catalyst for Growth, and (3) The Safety Dance: Navigating Safety and Risk. These themes highlight the role of LPP in fostering children’s engagement with risk, the impact of risky play on resilience and confidence, and the challenges staff face in balancing safety with developmental opportunities. Discussion: This thesis discusses the importance of program staff in shaping risky outdoor play experiences and navigating these environments. Findings emphasize the need for targeted training and policy development to support staff in fostering risky play within structured settings. Insights from this study can inform future interventions and contribute to creating environments that balance risky play with child development goals.