Envisioning the Role of Community-owned Stores & Aligning Federal Food Policies: A Participatory Approach to Food Security and Food Sovereignty in Sambaa K’e, Denendeh (Northwest Territories, Canada)

Northern Indigenous communities have relied on traditional food systems for meaningful, nutritious diets since time immemorial. But many Indigenous communities in remote northern regions of Canada still face disproportionately elevated levels of food insecurity due to climate change radically altering the availability for traditional foods, colonial food policies imposing Western diets, and the high costs of transporting store-bought foods. Extreme weather events such as wildfires further isolate fly-in remote communities increasing both the costs of transporting store-bought foods and the difficulties of harvesting traditional foods. There are many examples of community-based initiatives for supporting traditional and locally grown foods, however, store-bought foods are usually neglected in these community-based food security and food sovereignty projects despite their increasing presence in northern diets. One of the many reasons for not focusing on store-bought foods, compared to traditional or grown foods, is that the majority of remote Northern communities have only one corporate-owned for-profit store that reduces the agency of community members to enact food system changes. This creates an urgent need for community-based initiatives to address simultaneously the high costs of store-bought foods and ensure that these initiatives are aligned with local visions for food sovereignty. Working with Sambaa K’e First Nation (SKFN), a Dene Nation in the Dehcho region of Denendeh (Northwest Territories, Canada), this thesis presents both a participatory action research case study and a policy change proposal for the Nutrition North Canada (NNC) retail subsidy to address the unique challenges for community-owned stores in remote Northern Indigenous communities. This study, using shop-along interviews, found that the community-owned store supported some pillars of food security, such as the availability of nutritious foods and its utilization, more than others. However, despite local efforts to reduce prices for whole foods and provide a space for free garden foods, economic access to nutritious food was mostly determined by the cost of flying in store-bought food and the failure of federal food subsidies. Through analyzing anonymized Point of Sale records that tracked purchases for two years, we show that SKFN missed out on between $56,514 and$70,910 per year in NNC retail subsidy dollars due to the current administrative barriers within the retail subsidy. This figure is the first estimate of the value of subsidies missed out by a remote, NNC eligible community. We then propose a change to the NNC retail subsidy that subsidizes air freight at a fixed rate specifically for community-owned grocery stores. This change eases the administrative burden faced by small community-owned stores and increases ordering flexibility at comparable program costs

Velocity-Dependent Neural Strategies of Explosive Force Production: Insights from Motor Unit Behaviour and Velocity-Based Training

Velocity-Dependent Neural Strategies of Explosive Force Production: Insights from Motor Unit Behaviour and Velocity-Based Training By Jesse Collins PhD Candidate Wilfrid Laurier University DISSERTATION Submitted to the Department/Faculty of Kinesiology in partial fulfillment of requirements for the degree of Doctor of Philosophy © Jesse Collins 2025 Abstract The overarching purpose of this dissertation was to identify the neuromuscular mechanisms that contribute to explosive strength gains following velocity-based training (VBT). VBT prescribes training loads and intensities based on the speed of movement during an exercise, using real-time velocity feedback to adjust effort and optimize training outcomes. This approach aims to develop high-velocity force production, which may be particularly effective for enhancing explosive athletic tasks (e.g., sprinting and jumping) that are too brief in duration to reach peak torque. This work provides insight on how the nervous system controls force development across a wide range of contraction velocities and assesses how VBT might modify neural strategies, specifically, motor unit firing rates of the prime movers and patterns of antagonist and synergist muscle activation. This dissertation includes three studies which each address a key objective. The first objective (Study 1) was to investigate how motor unit (MU) firing behaviour is modulated during dynamic isokinetic contractions across a wide range of movement velocities, to better understand the neural control of rapid force production. A secondary aim of this study was to assess the feasibility of using multi-electrode surface array electromyography decomposition to measure MU behaviour during high-velocity dynamic tasks. This study demonstrated that while decomposition is feasible during dynamic movement, limitations in detecting high-frequency discharges, specifically during the early-phase of the contraction (first 50ms), highlights the need for more sensitive methods to fully characterize neural drive during explosive tasks. The second objective (Study 2) was to assess how MU firing behaviour adapts to produce different contraction velocities during isotonic movements. Our results revealed that the muscle activation strategy changed over the course of the contraction. Specifically, during the early phase (first 50 ms), motor unit firing rates and the speed at which units were recruited varied based on the intended movement velocity. In contrast, during the later phase of the contraction, firing rates increased primarily in proportion to the torque being produced. Additionally, velocity-dependent modulation of antagonist and synergist muscle activation was observed during jumps at different velocities which suggests that coordinated adjustments in intermuscular control may be used to match specific task demands. The third objective (Study 3) was to assess whether velocity-specific neural strategies, such as motor unit firing characteristics and patterns of antagonist and synergist muscle activation, are trainable. Twenty-one resistance-trained athletes completed a four-week VBT intervention. which resulted in improvements in early-phase rate of force development (RFD) and synergist muscle activation Although we did not observe group-level changes in MU discharge rates, individual performance gains were correlated with increases in initial rate of force development and increased motor unit firing rates following training. This highlights inter-individual variability in adaptations to VBT. All together these studies show how VBT influences neuromuscular control of force during dynamic movement with evidence that both muscular adaptations (e.g., increased rate of twitch force development) and neural mechanisms (e.g., increases in motor unit firing rates associated with performance gains) contribute to these effects. This provides mechanistic insight into how the nervous system and musculature may adapt to velocity-specific training interventions. These results may also have practical implications for designing individualized training and rehabilitation programs that optimize rapid force production by targeting both neural timing and mechanical output under specific velocity constraints

Children\u27s Peer Selection in STEM: The Influence of Gender, Ethnicity, and Disability

The present study examined how children’s peer selection in STEM (science, technology, engineering, and mathematics) may be influenced by gender, ethnicity, and physical disability. Sixty-four children (ages 6-12) from elementary schools in Southwestern Ontario completed three tasks: a simulated peer selection task, an attribution of ability task, and a stereotype belief questionnaire. In the peer selection task, participants were repeatedly asked to select one peer from a set of AI-generated photographs showing children who differed by gender (male, female), ethnicity (White, Black, East Asian), and physical disability status (able-bodied user vs. nondisabled). The Peer Selection Task was based on the Peer Selection tasks in Wauters and Roberts (2022) study. For each of 16 scenarios in the Peer Selection task, four in each STEM domain (Engineering, Math, Science, and Technology), participants chose a partner and then rated each peer’s perceived ability in each area of STEM. Participants were also asked to verbally explain the reasoning behind why they selected the peer that they did, allowing for qualitative analyses of reasoning patterns. Results revealed that both males and females were selected more than chance, however there was no consistent preference for males in STEM, although, in-group gender preferences emerged, especially among males. Additionally, males were still preferred in engineering, highlighting that it may still be a male dominated domain. This finding suggests that in-group preferences, as well as gender stereotypes may potentially contribute to children\u27s peer selection. No significant preferences were found for ethnicity or physical disability. Ethnicity based differences were minimal suggesting that although children may be aware of ethnic stereotypes, these may not yet be applied in academics consistently. For physical disability, peers with disabilities were selected less often in unadjusted data selections, which may suggest competence-based exclusion. However, when data was adjusted to account for unequal selection probability, no significant differences between selecting an able-bodied peer or a peer with a physical disability were found. Exploratory analyses also found that children’s justification for selecting peers to collaborate with was mainly based on cognitive ability (i.e. who seemed smart or skilled). Task-specific reasoning, such as experience, and perceived task fit, relates peers\u27 traits to the perceived task competence. Social factors, such as friendliness and cooperation, were also frequently mentioned, particularly when children explained selecting peers with physical disabilities. Importantly, while moral reasoning occasionally led children to select peers with physical disabilities out of fairness or inclusivity, this was not the only pattern, and ability-related reasoning remained most common. Together, these findings highlight the possible importance of social stereotypes and in-group preferences in shaping children’s collaborative decision-making in the STEM field. Even at an early age, children may demonstrate in-group biases and rely on visible physical differences when making STEM collaboration choices. These results align with Social Learning Theory and bio-cognitive perspectives, which highlight both social reinforcement and natural categorization processes in stereotype formation. The findings highlight the need for interventions that address biases early, particularly by promoting inclusive group work practices and challenging assumptions about competence involving gender, ethnicity, or physical disability. By examining both the patterns of selection and the reasoning children provide, this study offers a nuanced view of how stereotypes may operate in academic collaboration and provides a foundation for future research examining broader disability categories and more diverse ethnic groups. Implications for stereotype development theories, inclusive education, and equity in STEM participation are discussed

Mapping Climate Risks & Building Resilience: A Participatory Approach to Harvester Safety in Kakisa, NWT.

The Ka’a’gee Tu First Nation (KTFN) community in the Northwest Territories is experiencing rapid environmental changes which are driven by climate change. These changes are threatening the community’s food security. The community is seeing a disruption to its traditional land-based food systems due to increasing climate risks such as unpredictable weather, thawing permafrost, wildfires, and flooding. These changes are reducing access to traditional foods and intensifying threats to harvester safety. Building on the existing relationship with the community through previous projects, this thesis examines the impacts of climate risks on the availability and access of the KTFN’s on the land harvesting practices with a particular focus on harvester safety. Using a Participatory Action Research approach, the study conducted a community-led workshop that included the use of semi-structured interviews and a participatory mapping session to document harvester experiences on the land amidst climate change. The research reveals three core themes: declining availability and access to traditional food sources, increased environmental risks to harvesters such as unstable ice, wildfires, flooding, predator encounters, and community-driven adaptation and resilience efforts. Changes driven by climate change, such as permafrost thaw, shifting migration patterns, and unpredictable weather, have made the community’s traditional harvesting routes riskier and more difficult to access. Despite these challenges, the KTFN community is coming up with adaptation strategies which include the expansion of safety infrastructure on the land, community-led environmental monitoring, and active advocacy for their land sovereignty. This thesis, therefore, highlights the ongoing impacts of climate change on the KTFNs’ ability to access and maintain traditional food security and reveals the community’s proactive efforts in adapting and sustaining their cultural harvesting practices

Neural Correlates of Cognitive Fatigue in Regular Cannabis Users and Non-users: A Pilot fNIRS Study

Background: Cognitive fatigue impairs performance across multiple domains, yet how regular cannabis use affects fatigue responses remains unclear. This pilot study investigated neural and behavioural correlates of cognitive fatigue in abstinent cannabis users versus non-users. Methods: Twenty-six participants (18 non-users, 8 regular cannabis users after 24-hour abstinence) completed cognitive tasks before and after a 60-minute Sustained Attention to Response Task (SART) designed to induce fatigue. Tasks assessed working memory (N-Back), cognitive flexibility (Wisconsin Card Sorting), psychomotor speed (Digit Symbol Substitution), sustained attention (Continuous Performance Task), inhibition (Stroop, Stop Signal), and motion perception. Functional near-infrared spectroscopy (fNIRS) continuously monitored prefrontal cortex activation across 20 channels organized into 7 regions of interest. Results: Both groups reported increased subjective fatigue (VAS-F) post-SART. Behaviourally, most cognitive tasks showed practice effects rather than fatigue-related decrements. FNIRS revealed divergent patterns: non-users showed increased prefrontal HbO values post-SART (110% increase), while cannabis users showed decreased HbO values (shifting from positive to negative). Effect sizes for group differences were medium to large for several tasks (Stroop, d = -0.58; Digit Symbol, d = -0.55; CPT, d = -0.50) despite not reaching statistical significance due to limited power. Conclusions: This exploratory study suggests abstinent cannabis users and non-users show opposing neural adaptation patterns to cognitive fatigue. While underpowered for definitive conclusions, the divergent hemodynamic responses warrant investigation with larger samples to understand how cannabis use history affects fatigue vulnerability. Keywords: Cognitive fatigue, mental fatigue, sustained attention, cannabis, fNIRS, neuroimaging, prefrontal cortex, motion coherence, pilot stud

The disruption of gastrointestinal hormonal control of digestion in Nile tilapia by omeprazole

Stomach acidity is a critical feature of the digestive system, facilitating the breakdown of protein through the activation of the protease pepsin. Gastric acid is secreted by H+/K+ ATPase, the gastric proton pump. A previous study on Nile tilapia (Oreochromis niloticus) showed that inhibiting the production of stomach acid using the proton pump inhibitor omeprazole (omz), reduced growth that correlated with an acceleration of the rate of gastric emptying. This contrasts with omz exposure studies in mammals in which there is a delay in gastric emptying and no impact on growth. To understand the mechanism behind rapid rates of gastric emptying in tilapia; the role of cholecystokinin (CCK) was examined in this study. CCK controls the rate of gastric motility as it contracts the most anterior part of the intestine to delay gastric emptying, holding food so that it can correctly go through the digestive process. Post-prandial changes in tilapia fed a fixed ration of 2% body mass day-1 of pellets either with (25mg kg-1 d-1) omeprazole or without was examined. Omeprazole treatment replicated the decrease in gastric acid secretion (88-94%), increased gastric emptying and decreased specific growth rate (30%) previously observed. Significantly, it lowered circulating plasma CCK concentrations and lowered cck gene expression in the anterior intestine as well as cckb receptor (cckbr) levels in the stomach, which is associated with the binding of the CCK hormone and gastrin (responsible for stimulating gastric acid secretion and motility) hormone that stimulates acid secretion. Together these results suggest a reduced release of CCK that would explain the accelerated rate of stomach emptying seen in tilapia. The expression of additional genes was looked at to determine the differences between omz vs sham treatments. While the expression of growth hormone and pepsinogen genes showed statistically significant differences, other genes showed no differences. A feeding trial was conducted to observe whether fish on an omeprazole diet could compensate for their reduced growth with an increase in appetite and food intake. Instead, there was no increase in food intake in omeprazole fed fish compared to the sham, with no difference in expression of genes for hunger at the transcriptional level. My study observed the interactions of gastric acidification and its relationship to the endocrine system on a molecular level not only with CCK but other hormones and genes that are influenced by gastric acidification, bridging the gap in knowledge between the interaction of the endocrine systems with the stomach in a teleost species

Nanoparticle carriers enhance the prophylactic antiviral effects of dsRNA in vitro and ex vivo

Aquaculture now outpaces traditional capture fisheries as the world population and demand for sustainable protein sources increases. Wild and farmed species are increasingly susceptible to pathogen spread as global temperatures rise and stocking densities increase. Despite the devastating losses experienced by aquaculture due to viral infections, there remain few effective prophylactic antiviral therapeutics. Long double-stranded (ds)RNA is a uniquely viral molecule produced by nearly all viruses during their replication cycle, and its detection by salmonids like rainbow trout (Oncorhynchus mykiss) and chinook salmon (Oncorhynchus tshawytsha) leads to the establishment of a defensive antiviral state. Previous in vitro studies demonstrated a reduction in the severity of viral infections following prophylactic treatment by long dsRNA delivered by nanoparticles). This dissertation determined that: i) the toxicity imparted by cationic stearylamine liposomes outweighed their protective capabilities in vitro, ii) phytoglycogen nanoparticles enhanced the antiviral protection of HMW poly I:C in vitro, iii) HMW poly I:C delivered by phytoglycogen nanoparticles enhanced peripheral blood leukocyte phagocytosis, antiviral gene expression, and metabolism ex vivo while also inducing antiviral gene expression in ex vivo intestine models, and iv) the loss of the cytosolic PRR MDA5 decreased the responsiveness of chinook salmon embryonic cells to dsRNA over 500bp and increased susceptibility to viral infection. Together, this foundational knowledge can direct further investigations into the potential of nanocarriers to enhance antiviral protection in vivo. to protect the growing aquaculture industry against significant losses from viral infections and inform disease management strategies in wild populations

Exploring Parent-Child Reminiscing Style and Internal-State Talk When Discussing Positive and Negative Shared Events

Conversations between parents and children about past events play a critical role in children’s social, emotional, and cognitive development. Parents scaffold their children in learning to recount details of their autobiographical memories by creating a space to reflect on internal states, specifically emotions and cognitions. Parents with an ‘elaborative’ reminiscing style are responsive to children’s utterances and ask open-ended questions (e.g., What do you remember about...?). Parents who are less ‘elaborative’ typically ask narrow questions like Did you like it?” that do not encourage conversation. Children whose parents use an elaborative reminiscing style have children who produce the most detailed narratives. While these conclusions are mainly based on conversations of positive events, the present study aimed to examine how children’s internal-state talk (IST) differs when reminiscing about positive and negative events, as well as how children’s internal-state talk is influenced by parents’ reminiscing style. Memories of negative events are qualitatively different to memories of positive events with the former focusing on what happened and the latter focusing on the meaning of the event. Thirty parent-child dyads (ages 3-6) reminisced two shared events, a positive event and a negative event. Parent-child conversations were transcribed and coded for children’s internal-state talk (emotional and cognitive IST), as well as parents’ reminiscing style. The results showed that children used more internal-state talk, specifically emotion IST, during discussions of negative events compared with positive events. Contrary to previous research, parents’ use of low elaboration strategies did not hinder children’s use of internal-state talk. No significant interactions were found between event valence and reminiscing style

Variables Related to School Readiness Among Canadian Children With Attention Deficit Hyperactivity Disorder Symptomology

Children with attention deficit hyperactivity disorder (ADHD) symptoms face challenges academically, behaviourally, and socioemotionally at entry to formal education. Yet, these symptoms are rarely investigated prior to school entry, reducing the time that parents can prepare by learning about the disorder, scaffolding their children’s skills, and mediating the risk of long-lasting consequences related to unpreparedness for school. Within the current study, we aimed to uncover specific skills and elements within children’s environments which may be targeted for intervention prior to entering formal education. More specifically, we examined the relationship between the home literacy environment (HLE), mental-state understanding, ADHD symptomology, and school readiness in Canadian preschool children ages 4 to 6 years old. Parents completed an online survey and parent-child dyads participated in a videoconferencing session. The survey included assessment of children’s ADHD symptomology (Conners 3-P(SF), mental-state understanding (Children’s Social Understanding Scale), and two measures of family HLE. First, an assessment of parental knowledge of children’s picture books, (Title Recognition Task) a proxy measure of the HLE, and second, survey questions more directly assessing the HLE (i.e., number of books in the home). The videoconferencing session included three tasks for the child and one for the parent-child dyad. The child was administered a standardized test of school readiness (Wide Range Achievement Test, 4th edition), a direct assessment of mental-state understanding (modified Smarties task), and an audio-visual measure of their picture book knowledge (Book Cover Recognition Task; BCRT), created for this study. The parent-child dyad participated in a shared book reading session as a final proxy measure of the HLE. Lastly, ADHD symptomology was observed and noted throughout the videoconferencing session. Correlations were computed to determine the degree of association between all variables. Unique variance in school readiness which may be explained by participants\u27 mental-state understanding, ADHD symptomology, the family HLE, and control variables was examined. ADHD symptomology emerged as the strongest predictor of school readiness. Greater ADHD symptoms were correlated with diminished mental-state understanding and school readiness. Mental-state understanding was related to greater school readiness and, to a lesser degree, the HLE (as measured by book exposure only). Finally, the HLE was positively correlated with school readiness, when measured with book exposure. Shared book reading was not correlated with school readiness, mental-state understanding, nor ADHD symptomology. Contributions of the current study include the successful development of a new measure of preschool ADHD symptomology (ADHD observation rubric), an improved measure of children’s book exposure (BCRT), and the extension of the theory that it is the quantity of shared book reading interactions which contribute to school readiness and mental-state understanding, not the quality. Further implications are discussed

Minority Stress and Drug Use among 2SLGBTQ+ Canadians

Background: Several social and environmental factors influence drug use behaviors and contribute to frequent drug use among Two-Spirit, Lesbian, Gay, Bisexual, Transgender, Queer, and other (2SLGBTQ+) individuals. The purpose of the current study was to examine the relationship between the minority stress, drug use, and other socio-ecological factors. Methods: This study employed structural equation modelling on data (2021—2022) from a nationally representative pan-Canadian survey (N = 1542) on 2SLGBTQ+ health to examine the association between minority stress, drug use, and relevant socio-ecological predictors. A separate mediation analysis was conducted and controlled for socio-demographic characteristics. Results: SEM results showed parsimonious fit of data [chi-square = 526.86 (df = 61, p \u3c 0.0001), SRMR = 0.04, RMSEA = 0.07 (95% CI = 0.07, 0.08), AGFI = 0.92, and CFI = 0.95]. The direct path of minority stress on drug use was significant (β = 0.07899, p = 0.0005) and other indirect effects were observed. Psychological distress significantly mediated the relationship through an indirect pathway (β = 0.07, p \u3c 0.0001). Conclusions: Minority stress and drug use are inter-related through direct and indirect paths and psychological distress plays a crucial role in mediation. Study findings add valuable insight to the field of substance use and addiction by deepening our understanding of the mechanisms behind drug use in the population