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Heterogeneous environments impose discordant selective pressures on natural populations, where disparate biotic/abiotic factors and variable population connectivity, yield mosaic patterns of genetic variation on the landscape. The ability to maintain or change genetic mosaics of populations becomes key to persistence, as species increasingly need to adapt to rapidly changing environmental and human-associated selective pressures. Specifically, infectious diseases can impose strong and rapid selective pressures on populations, where anthropogenic disruptions of co-evolutionary patterns and altered distributions of hosts and pathogens exacerbate disease risk. Genomic tools provide means to evaluate disease-associated impacts on the genetic landscape of host populations and facilitate implementation of informed conservation efforts. In this thesis, I evaluate disease dynamics in: 1) a long-standing arctic rabies/arctic fox (Vulpes lagopus) system affected by influxes of red fox (V. vulpes), and 2) an invasive bat pathogen system, where the North American introduction of Pseudogymnoascus destructans (Pd) has had variable impacts on bat species and populations. In these systems, signatures of host selection were estimated from temporal and spatial shifts in allelic diversity within genomic regions associated with immune response, highlighting different host mechanisms to enzootic and invasive diseases. In the arctic rabies/fox system, pathogen variants did not influence red fox local disease responses, reflecting more recent expansions of this host to Arctic regions. In contrast, arctic fox revealed genomic patterns consistent with long-term, co-evolutionary processes. In Pd/bat systems, genomic evidence supported the hypothesis that eastern small-footed bats (Myotis leibii) were inherently resistant or tolerant to Pd, the causative agent of white-nose syndrome (WNS). In contrast, WNS-impacted little brown bat (M. lucifugus) populations had varied genomic impacts subsequent to strong selective sweeps from disease. My research illustrates how immunogenetic profiling, in context of demographic processes inferred from neutral genetics, enhances understanding of the varied impacts of changing disease landscapes on host populations/species; insights relevant to other host-pathogen systems. Building on this thesis, future explorations of low coverage genomes, host-imposed reciprocal selection, and impacts on methylation, transcriptomic and proteomic patterns associated with shifts in genetic diversity, would enable more holistic understanding of the geographic mosaics within these disease systems.

Author Keywords: Disease Dynamics, High-throughput Sequencing, Immune System, Natural Selection, Population Genetics, Reduced Representation Sequencing

Since the 1960s, post-secondary institutions (PSIs) across Chi'Mikinak (the Great Turtle) have been learning how to engage with Indigenous Knowledge Holders and their knowledges in academic programs and research, to decolonize, to support Indigenous-led initiatives, and make systemic, transformative, and reconciliatory change. This work explores what practices support and nurture Indigenous autonomy in relation to Indigenous Knowledge systems in four Canadian, Indigenous-focused post-secondary education (PSE) programs. It considers how to embody and activate these practices as individuals and institutionally, as well as the issues, tensions, opportunities, and prospects for doing so. Co-learning and co-creating are possible. However, Indigenous autonomy (often framed as control) demands rebalancing and restructuring of asymmetrical Indigenous/settler relations on the land, in governance, in the academy, and settler society. Indigenous inclusion in PSE does not result in structural, transformational, reconciliatory, or Indigenizing change, but rather, Indigenous Peoples say they are constrained within colonial governance structures and frameworks. Thriving prospects for upholding Indigenous relational autonomy and Indigenous Knowledge sovereignty in Indigenous programming is rooted in Indigenous governance, which inherently centres local Indigenous Peoples, their lands, knowledges, languages, histories, and spiritualities. It also requires settler peoples "to Treaty" their way forward using Treaty epistemologies and ontologies to uphold Treaty values, relationships, and responsibilities, and to create ethical spaces for Indigenous governance. The experiences, stories, and understandings of the Traditional Advisory Council of the Indigenous Studies Ph.D. program, plus 14 Indigenous Knowledge Holders and 20 settler people associated with three programs at the Chanie Wenjack School of Indigenous Studies at Trent University, as well as insights from Mi'kmaw Dr./Elders Murdena and Albert Marshall regarding the former Toqwa'tu'kl Kjijitaqnn/Integrative Science program at Cape Breton University, ground and guide this work. The work utilizes transdisciplinary and qualitative approaches, including co-learning, etuaptmumk (the gift of multiple perspectives), Indigenist, decolonizing and settler-colonial theory, within relational and Treaty-based accountability ethics. It draws from Indigenous-centred literature. It contributes to Indigenous, settler-colonial, reconciliation, and political studies; knowledge engagement, translation and mobilization; systemic change; Treaty education; co-learning; transdisciplinary and transcultural education and research; and Indigenous-settler alliances. The findings are relevant to PSIs across Chi'Mikinak.

Author Keywords: Albert and Murdena Marshall, Co-Learning and Two-Eyed Seeing, Indigenous Education, Indigenous Knowledge Systems, Systemic Change in Settler-Colonial Education, Treaty Education in Canada

Predicting vehicle speed at critical road segments, such as pedestrian crossings during left-turn maneuvers at signalized intersections, is essential for improving traffic safety and supporting autonomous driving systems. This thesis presents a novel two-stage hybrid deep learning framework enhanced with reinforcement learning to forecast vehicle left-turn speed at pedestrian crossings.

Using a multivariate time series dataset of vehicle speed and acceleration, the final three seconds of data are intentionally removed to simulate real-world decision-making prior to reaching pedestrian crossings. In stage one, a Convolutional Neural Network (CNN) imputes the removed values. Stage two uses the imputed data to forecast speed, combining Temporal Convolutional Networks (TCNs) and Long Short-Term Memory (LSTM) networks as feature extractors, followed by a Random Forest Regressor (RFR) for robust speed predictions.

Reinforcement learning is employed to dynamically adjusts the TCN's dilation rate, improving temporal pattern capture. Experimental results show the proposed framework outperforms standalone, hybrid, and state-of-the-art models.

Author Keywords: Data Imputation, Dynamic Dilation, Left-Turn Maneuver, Reinforcement Learning, Temporal Convolutional Network, Time series Forecasting

Dissolved organic matter (DOM) plays a vital role in lake ecosystems, yet its temporal and spatial variations in lakes remain poorly understood. This study investigates DOM dynamics in boreal lakes during the warm season and the Laurentian Great Lakes ice during winter. Sampling 10 boreal lakes in early and late June 2022, revealed subtle changes in DOM in the epilimnion and hypolimnion related to factors such as water residence time and stratification strength. In ice from the Great Lakes, lower dissolved organic carbon concentrations and a higher proportion of protein-like DOM were found compared to water, which mostly contained terrestrial-like DOM. Ice DOM composition varied with factors such as ice thickness, water nutrients, and DOM concentration in ice and water. In addition, we found that the potential release of protein-like DOM from ice to the water during spring melt is considerable and may fuel heterotrophic microbial metabolism.

On many farms, stone and wooden field borders define field sizes. These are commonly perceived as land lost to production and refuges for pests and disease, causing such fences and hedges to be removed to create larger fields for increased productivity; this process has eliminated trees and shrubs that provide habitat along these fencerows. This research explores the alignment of agricultural productivity and wildlife conservation, proposing that species such as feral apples may serve as direct economic resources for producers and act to protect such remaining fences and hedges. This study focused on farms in the Dummer Moraine, which have small fields, adventive hedges on rock piles and rail fences. Using field size analysis, apple frequencies and apple jelly tasting, the research demonstrates that feral apples could provide economic incentive for keeping these hedges intact, offering a practical mechanism for their conservation, benefiting both biodiversity and farm productivity.

KEYWORDS: biodiversity conservation, farm gate sales, fencerows, feral apples, hedges, linear forests

Author Keywords: biodiversity conservation, farm gate sales, fencerows, feral apples, hedges, linear forests

Risk-taking (e.g., dangerous driving, substance use) rises during adolescence and can result in both adaptive consequences (e.g., social acceptance) and maladaptive consequences (e.g., alcohol poisoning, premature death). Adolescents also experience an increase in self-conscious emotions, including shame. Shame-prone adolescents may engage in risk-taking to cope with negative self-perceptions. Previous research is contradictory, however, finding shame and risk-taking to be positively correlated, negatively correlated, or not related at all. One reason for this may be that shame was assessed as an overall construct. Some conceptualizations of shame dictate that people can experience several types of shame, including body (e.g., shame about physical appearance), character (e.g., shame of personal habits), and behavioural (e.g., shame about doing something wrong). Our study fills this gap by examining how different types of shame are related to different types of risk-taking behaviours and subsequent outcomes. Practical implications and directions for future research are discussed.

Author Keywords: Adolescence, Behaviour shame, Body shame, Character shame, Emerging adulthood, Risk-taking

In situ chlorophyll sensors are beneficial for monitoring of long-term impacts of algal blooms and accessing water quality issues in bodies of water. However, more research is needed to validate their efficacy and understand how environmental conditions can influence sensor measurements. I assessed the performance of an in situ chlorophyll sensor under controlled environmental conditions and used the same sensor to collect vertical phytoplankton patterns in south-central Ontario boreal lakes. The performance of the sensor was assessed by examining the precision of chlorophyll measurements and determining the suitable timing length that would produce precise results. In general, the sensor was relatively insensitive to conditions under lower algal concentrations and the decent of the sensor should be slowed for vertical lake profiling in lakes with higher algal biomass. Most variation resulted from the movement of particle bound algal cells. We described chlorophyll profile characteristics including surface chlorophyll levels and chlorophyll peak depth and width and investigated the relationships of these features with environmental controls. The lakes showed a typical chlorophyll profile of low phytoplankton biomass lakes. Our results showed that dissolved organic carbon was a strong predictor of epilimnetic biomass while light attenuation and dissolved organic carbon were both strong predictors of peak depth. Light attenuation and surface area were small but significant predictors of peak width. We acknowledged that any uncertainties in sensor chlorophyll readings were not an issue in our lakes due to the overall low chlorophyll biomass.

Author Keywords: chlorophyll, chlorophyll fluorescence, in situ profiling, lakes, phytoplankton biomass, water quality 

Using Drosophila deficiency (Df) and Over Expression (OE) (GAL4/UAS>dCas9-VPR; sgRNA) gene systems, it was demonstrated that Dmel_CG31381 and Dmel_CG11089 are functional tRNA isopentenyltransferase (EC 2.5.1.8) genes (tRNA IPT1 and IPT2) critical to the first committed step in insect cytokinin biosynthesis. IPT Df mutants showed significant decreases in total CK levels and IPT1/IPT2 transcript levels compared to parent lines. IPT OE mutants showed significant increases in total CK levels and IPT1/IPT2 transcript levels compared to parent lines. Further, endogenous CK analyte levels and qPCR relative fold gene expression of Dmel_CG31381 and Dmel_CG11089 (tRNA IPT1 and IPT2) genes demonstrated expression patterns with functional confirmation corresponding to the predicted IPT mutant variants. The functional confirmation of tRNA IPT1 and IPT2 as the first committed step was further supported by the bioinformatic detection of putative gene homologs to corroborate seven remaining enzyme transcripts supporting the novel description of a CK biosynthesis pathway in insects.

Author Keywords: Cytokinin Biosynthesis, Drosophila, gene expression, Insect Gall, mass spectrometry, tRNA IPT

This study explores the connection between the historical occurrences and the landscape changes on Main Duck Island, located at the eastern end of Lake Ontario. This research is conceptualized within the framework of Maritime Cultural Landscapes (MCL) to understand the relationship between the landscape and Lake Ontario. To explore this relationship, the study integrates spatial and archaeological methods such as GIS-based paleoshoreline modeling to understand the landscape change over time, analysis of air photographs, visibility analysis (viewshed) to understand island mobility, archaeological reconnaissance survey to discover and rediscover archaeological sites on the island, and ceramic analysis of surface finds to identify decorative motifs to establish cross cultural similarities between finds on mainland Canada and New York. This study is significant in contextualizing historical events such as Indigenous and non-Indigenous migration with landscape changes and archaeological data. Ultimately, the study corroborates past environmental conditions that have influenced the island's morphology with contemporary ones.

Author Keywords: Archaeological Reconnaissance survey, GIS (Geographic Information Systems), Island Archaeology, Maritime Cultural Landscapes, Paleoshoreline Modelling, Viewshed Analysis

The global shift toward sustainability has prompted brands to promote their sustainability initiatives on social media, aiming to connect with pro-environmental consumers. However, this strategy comes with risks, as social media allows for swift and widespread backlash if consumers perceive greenwashing. The present work examines the impact of social media backlash toward a brand's sustainability initiatives on consumers' purchase intentions. In an experimental study (N = 553), participants were presented social media responses to a fictitious brand's sustainability initiative that were either negative, positive, or a mix of both. The findings indicate that the negative comments decreased purchase intentions for consumers with a pro-environmentalist identity but not otherwise. Moreover, this effect was mediated by decreased perceptions of value-congruence with the brand. This study contributes to larger academic discourses on sustainable marketing, greenwashing, and consumer-brand relationships while providing tangible recommendations to marketing practitioners attempting to mitigate the challenges posed by social media backlash.

Author Keywords: greenwashing, social identity, social influence, social media backlash, sustainability promotion, value congruence