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ENERGY TRANSITION IN SMALL COMMUNITIES UNDER UNCERTAINTY
No full textTransitioning small and remote communities to renewable energy is critical for achieving global net-zero targets. These communities, reliant on costly and emission-intensive fossil fuel systems, require tailored renewable energy frameworks and robust planning strategies to ensure reliable, sustainable, and cost-effective energy solutions. This dissertation addresses these needs through two interconnected themes: designing renewable energy systems specifically suited to local conditions and strategically planning transitions to net zero under uncertainty. In the first theme, advanced optimization models are developed to assess hydrogen's potential as seasonal energy storage, aligning social, economic, and environmental objectives. Results demonstrate significant potential for hydrogen to enhance energy reliability, reduce fossil fuel dependence, and support sustainability. By 2050, strategic deployment of hydrogen and wind power is expected to double capacity, substantially decreasing reliance on external grid connections. Further analyses cluster remote Canadian communities based on resources, climate conditions, and energy demand patterns, revealing hydrogen storage's effectiveness in mitigating seasonal energy fluctuations. Acknowledging the critical role of uncertainties in renewable energy transitions, the second theme introduces multi-stage stochastic robust optimization techniques to handle short-term energy variability and long-term uncertainties such as technology cost developments and evolving carbon policies. The findings highlight that phased investment strategies considerably outperform single-phase transitions, enhancing economic and environmental outcomes. Additionally, assessing the feasibility of waste-to-energy technologies alongside other renewable energy systems is crucial for boosting overall system reliability. Specifically, pyrolysis emerges as an adaptable, cost-effective solution, significantly lowering hydrogen production costs and effectively integrating waste management with broader renewable energy strategies. The thesis delivers frameworks for informed, resilient, and efficient renewable energy transitions in small, remote communities
Synthesis and Evaluation of Telluorophene- 2 BODIPY Photosensitizers Appended to Estradiol
No full textEffect of Sugar Kelp on Soil Health, Greenhouse Gas Emissions and Yield in Potato Cropping System
No full textOrganic fertilizers, such as sugar kelp (SK), are gaining recognition as sustainable alternatives to inorganic fertilizers due to their ability to improve soil health and reduce environmental impacts. This study assessed the effects of SK and its combinations with inorganic fertilizer (IF) on soil health, greenhouse gas (GHG) emissions, and the growth and yield of potato crops during the 2023 and 2024 growing seasons in Prince Edward Island, which is Canada’s largest potato-producing province. In 2023, four treatments were implemented: SK alone at a rate of 2 tons per hectare, IF alone (which satisfied the entire nitrogen requirement), a combination of SK and IF (providing a 50%-50% nitrogen contribution), and a control group with no fertilizer. The following year, the treatments included IF alone, a combination of SK and IF (fully meeting the nitrogen requirement), a combination of SK and IF (fulfilling 80% of the nitrogen requirement), and a control. Chemical analyses of the soil indicated that pH, organic matter (OM), calcium (Ca), magnesium (Mg), and cation exchange capacity (CEC) remained consistent across all treatments. Trace elements, including copper (Cu), iron (Fe), and zinc (Zn), showed only minor fluctuations. However, the application of SK significantly raised soil sodium (Na) levels in both years (p < 0.05). In 2024, nitrate (NO₃⁻-N) concentrations were significantly elevated in IF treatments compared to the control. There were no significant differences in cumulative CO₂ emissions and CH₄ uptake among the treatments for either year. The fertilizer-only treatments recorded the highest cumulative N₂O emissions, while the treatments that combined SK with reduced IF resulted in significantly lower N₂O emissions, comparable to those observed in the control group. Notably, these reduced-emission treatments did not display significant differences in Normalized Difference Vegetation Index (NDVI) or potato yield compared to treatments that utilized full IF, which had significantly greater values than the control. In summary, the findings indicate that integrating SK with reduced IF can sustain potato yields while markedly decreasing N₂O emission
PROBING THE DEGRADATION MECHANISMS OF LI-ION CELLS CONTAINING SILICON AND SINGLE-WALLED CARBON NANOTUBES
No full textPhD thesis examining the degradation mechanisms of silicon-containing lithium-ion cells with single walled carbon nanotube additives.This work explores the improvements that can be made to energy density by changing the active materials within the negative electrode. Current batteries use graphite as the lithium-storing active anode material as it can reversibly incorporate lithium atoms efficiently and safely. Swapping graphite for a different kind of active material such as silicon presents many advantages but also many challenges surrounding lifetime. Silicon provides almost 10x the specific capacity of graphite and is incredibly abundant but experiences strong capacity fade due to its surface interaction with the electrolyte. The volume expansion silicon experiences during lithiation leads to constant parasitic chemical reactions and mechanical degradation leading to early cell failure.
The introduction of a silicon anode in place of graphite improves stack energy density by up to 59%. The work done in this thesis explores alternative anode active materials including silicon and silicon based composite particles by evaluating their energy density and cycle life. Silicon active materials showed promising results when used in conjunction with single-walled carbon nanotubes and a conductive additive. The addition of carbon nanotubes to the electrode coating process allowed the use of common binders as it creates a strong electrical network between active particles that can withstand large volume changes.
To further the development of silicon negative electrodes their degradation mechanisms and failure pathways in full cells must be fully understood. In-situ stack pressure, in-situ gas evolution and post cycling differential voltage analysis are used to pinpoint and track capacity loss mechanisms in full cells. These results highlight the failure of silicon based full cells as lithium inventory losses due to the constant SEI forming reactions on the anode. These results reinforce the need for engineered silicon composites that limit the particle volume fluctuations during cycling
EXPLORING THE GRIEF EXPERIENCES OF REGISTERED NURSES DURING THE COVID-19 PANDEMIC FOLLOWING PATIENT DEATH USING FEMINIST POSTSTRUCTURALISM
No full textRegistered nurses faced an unprecedented time while working during the COVID-19 pandemic. The purpose of this research was to explore the grief experience that registered nurses had during the COVID-19 pandemic following patient death. Eight participants were recruited using a purposive sampling strategy. Semi-structured interviews were used to understand this lived experience. Feminist poststructuralism and feminist poststructuralist discourse analysis was used to understand how nurses described and understood their lived experiences in a multitude of ways, influenced by social and institutional discourses. This research identified key themes in which registered nurses understand their own grief experience when patient death occurred during the COVID-19 pandemic. This study provides evidence on how traditional grief models do not fully account for nurses’ social and political dimensions of their emotional experience
Understanding the Colonial Foundations of the Sri Lankan Civil War: Implications for Peacebuilding
No full textThe Sri Lankan civil war (1983–2009) between the Sinhala-dominated state and the LTTE is often analysed in mainstream literature as a conflict rooted in discriminatory post-independence policies toward Tamils. While these accounts offer valuable insight into post-independence catalysts, they overlook the deeper structures that enabled a violent context to emerge. This study departs from such analyses by situating the trajectory of the conflict within the British colonial period (1815–1948). It examines administrative policies, constitutional reforms, and colonial ideologies that laid crucial foundations for civil war. Adopting a problematization of colonial structures as its methodological approach, the dissertation offers a critical re-narration of the war. In conclusion, it is argued that contextualizing the conflict within colonial legacies is vital for contemporary peacebuilding. Without this dimension, efforts risk reproducing the very structures that once facilitated violence, drastically limiting the prospects for peace
DEVELOPMENT OF A SCALABLE PROCESS FOR EXTRACTING AND PRESERVING ANTHOCYANINS OF HASKAP BERRIES FOR VALUE-ADDED PURPOSES
No full textHaskap berries are rich in anthocyanins. Optimal ultrasonication-assisted extraction
(UAE) conditions were established to recover anthocyanins from dehydrated haskap
berries (540 W; 62 °C; 64 min), which provided a total anthocyanin content (TAC) of 16
mg cyandin-3-O-glucoside (C3G) equivalence (C3GE)/g dry weight. Extracted haskap
berry anthocyanins can be microencapsulated by partially replacing maltodextrin with
inulin, demonstrating a promising substitute coating material. The developed microcapsule
using maltodextrin and inulin (1:1, w:w) had comparable characteristics to microcapsules
prepared by 100% maltodextrin in terms of C3G encapsulation efficiency (40%), moisture
content (6%), water activity (aw 0.17), particle size (5.1 μm), and protection of TAC at 35
°C after 6 months storage. Furthermore, haskap berry anthocyanins (10 and 50 μg/mL)
reduced significantly intracellular reactive oxygen species and lipid accumulation in
hepatocytes in vitro. This study concludes that microencapsulated haskap berry
anthocyanins as a potential functional food ingredient or natural health product for
steatosis management
Reaching Across the Distance: An Autoethnography of Ukrainian Landscapes in the Liminal Space
No full textRussia’s full-scale invasion of Ukraine in 2022 has intensified human displacement and environmental damage. Having lost my home in Ukraine and moved to Canada, I found myself in a liminal space, disconnected from my homeland. In this posthumanist autoethnography, I explore how I could engage with the Ukrainian landscapes from afar. To answer this question, I wrote an autobiographical timeline, in which I described the most important landscapes of my life. I combined it with the stories from six conversations about home with people from my personal network. What I learnt about myself and others enabled me to describe an inanimate agency, the Eerie, that hinders my connection with the Ukrainian land. I outlined the key elements of the Eerie: ambivalent feelings toward my family, postcolonial haunting, landscape loss due to war, internalized colonialism, and voicelessness. I found ways to counter each component and engage with my home landscapes beyond distance and destruction: through a persisting emotional bond, growing love for the new places, by imagining my way into the landscape’s way of being, sharing stories about landscapes, and listening to my body. This study offers a perspective on the presence of the Eerie in the postcolonial experience of displacement and invites story-sharing about landscapes we cherish to foster relationships between people
DECODING POULTRY WELFARE: AN INTEGRATED MACHINE LEARNING AND NLP FRAMEWORK FOR VOCALIZATION ANALYSIS
No full textThis thesis investigates how vocal behavior in poultry can be used as a window into their health and emotional state, offering a novel, non-invasive approach to welfare monitoring. Rooted at the intersection of bioacoustics, machine learning, and natural language processing (NLP), the research builds a dual-framework system: one focused on acoustic signal processing and statistical classification, the other on semantic and emotional interpretation of vocal patterns.
What makes this work distinct is its integrative use of AI — Using traditional classifiers like LSTMs and Random Forests and advanced transformer-based models such as BERT and Wav2Vec2.0. Beyond improving classification accuracy, the thesis emphasizes interpretability, scalability, and real-world deployment potential, addressing key gaps in current poultry welfare research.
By enabling continuous, automated monitoring of bird vocalizations, this work supports more ethical and efficient farming, with broader implications for smart agriculture, animal behavior research, and sustainable food systems.Poultry vocalizations serve as valuable, non-invasive indicators of health, stress, and overall welfare in farm environments. This thesis presents an integrated machine learning framework combining classical acoustic analysis and natural language processing (NLP) to decode these vocal cues. The first approach uses features like MFCCs, spectral contrast, and zero-crossing rates with models such as Random Forest, LSTM, and TabNet for classifying health, behavior, and stress. The second pipeline transcribes raw audio using Wav2Vec2.0 and applies BERT-based sentiment and linguistic analysis to detect welfare-related vocal shifts. Ensemble models showed strong generalization across welfare contexts, while NLP models uncovered subtle stress-induced vocal patterns. Scalable preprocessing with ThreadPoolExecutor enabled efficient handling of large datasets. These methods support the development of an on-farm, real-time monitoring system for early stress detection, reduced manual labor, and improved animal welfare—contributing to more ethical, sustainable, and productive poultry farming practices
Establishing a Spatio-Temporal Atlas of Gene Expression after Traumatic Spinal Cord Injury
No full textTraumatic spinal cord injury (tSCI) has no cure, and effective treatments will require targeting secondary injury mechanisms at specific times and locations. This demands understanding how gene expression changes across space and time. Previous transcriptomic studies lack spatial context due to tissue homogenization. To overcome this, spatial transcriptomics was applied to characterize spinal cord gene regulation after tSCI. Female Thy1-YFP mice (14–16 weeks) received moderate T12 contusion injuries and were sacrificed at 4 hours, 48 hours, and 7 days, with a naïve control. Coronal and longitudinal sections were analyzed using the 10x Genomics® Visium HD platform. Graph-based clustering, spatially variable gene detection, differential expression, cell-type deconvolution, and ligand-receptor analysis revealed region-specific patterns among ~16,500 genes. Neuronal and glial genes decreased, while transcription factors and immune-related genes increased. Egr1, Spp1, and Apoe showed dynamic spatiotemporal responses. Findings highlight spatial transcriptomics as a powerful tool to guide development of targeted SCI therapies