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Healing the land: a proposal for the former Pine Falls Paper Mill site
No full textPrior to the arrival of Europeans, Sagkeeng Anicinabe First Nation resided on, cared for, and utilized the lands and waters in what is now Fort Alexander #3. Following the industrial movement in the area, including the establishment of the Pine Falls Paper Mill, the lands, once rich in sustenance, slowly became exploited for capital gain. The Pine Falls Paper Mill opened in 1927 and operated until 2010. Since its closure and the demolition of its infrastructure, the land that once supported the mill operations has been left vacant, contaminated, and in need of healing.
The purpose of this practicum is to propose a remediation plan for the former Pine Falls Paper Mill site. Furthermore, it suggests a plan to transform the site into a place that supports native medicinal plants as its long-term goal. The sites’ design and supporting research propose a phased planning process to achieve the long-term goal.October 202
Characterization of the magnetically shielded room for the neutron electric dipole moment experiment at TRIUMF
No full textThe search for the neutron Electric Dipole Moment (nEDM) lies at the intersection of particle physics and cosmology. A discovery of a non-zero nEDM would signal new physics beyond the Standard Model due to its CP-violating nature, potentially helping explain the matter-antimatter asymmetry in the early Universe. The Standard Model predicts a neutron EDM of |dn| ∼ 10^−31 e·cm, far below current experimental sensitivity. Present limits set |dn| < 1.8 × 10^−26 e·cm (90% C.L.). The TRIUMF Ultracold Advanced Neutron (TUCAN) collaboration aims to improve this by an order of magnitude, targeting σ(dn) ≤ 10^−27 e·cm.
The standard method for nEDM measurement uses polarized Ultracold Neutrons (UCN) and the Ramsey technique of separated oscillatory fields. This requires highly uniform electric and magnetic fields, achieved within a Magnetically Shielded Room (MSR), which isolates the precession field from external interference. However, magnetic field inhomogeneities are a major source of systematic error, affecting UCN spin relaxation times and mimicking false EDM signals. Accurate characterization of the magnetic field environment is essential for reducing such errors.
This dissertation focuses on developing and optimizing the magnetic environment in the MSR to support the TUCAN experiment’s sensitivity goals. Initial evaluations showed that the MSR’s shielding performance was suboptimal, prompting further investigation and targeted improvements. Techniques such as magnetic shaking were used to enhance shielding, and detailed residual field mapping was conducted.
A custom-built mapping system was developed to assess the magnetic environment, with simulations used to correct for systematic uncertainties, including sensor inaccuracies, misalignments, and structural imperfections. These measurements enabled a clearer understanding of field sources and helped guide optimization efforts.
Overall, this work evaluates the MSR’s shielding effectiveness and readiness for nEDM measurements. The results inform ongoing improvements to the shielding and field uniformity and contribute to meeting the stringent requirements necessary for detecting or constraining the neutron EDM.October 202
NT-proBNP as a predictor of postoperative atrial fibrillation after thoracic surgery
No full textBackground: Postoperative atrial fibrillation following lung resection is associated with increased morbidity and mortality. The extent of pulmonary resection and preoperative N terminal pro-BNP (NT-proBNP) levels have been suggested as contributing factors in the development of postoperative atrial fibrillation. This study aims to determine if a relationship exists between the extent of lung parenchyma resected and perioperative changes in serum NT-proBNP levels.
Methods: We conducted a prospective cohort study enrolling patients aged ≥55 years undergoing pulmonary resection with no documented history of atrial fibrillation. Baseline NT-proBNP levels were measured preoperatively (PRE), in the post-anesthesia care unit (PACU), and on postoperative day 1 (POD1). The weight and volume of lung resection was determined from pathological review of the surgical specimen. Statistical analysis utilized repeated measure regression models with NT-proBNP as the outcome, incorporating measurement time (PRE/PACU/POD1), the extent of lung resection, and their interaction as predictor variables. Trajectory plots were generated to assess NT-proBNP changes after surgery and Spearman correlations were used to determine the relationship between NT-proBNP and extent of resection at each time point.
Results: 105 patients were enrolled, and 102 patients were analyzed. Postoperative atrial fibrillation occurred in 5 (4.9%) cases. Relative to PRE NT-proBNP measurements, the change in NT-proBNP levels at PACU and POD1 was -0.5 ± 37.9 pg/mL (p=0.905) and 320 ± 472.5 pg/mL (p <0.0001), respectively. No relationship between NT-proBNP and the extent of lung resection, defined using multiple outcomes, was demonstrated across all measurement times.
Conclusions: Lung resection was followed by a near four-fold elevation in NT-proBNP levels from baseline on the first postoperative day. However, there was no relationship between
perioperative elevations in NT-proBNP and the extent of lung resection.October 202
Ni(II), Pd(II) and Cu(II) Coordination Complexes of a -Extended Dianionic N^N-^N-^N Ligand: Synthesis, Structures and Electronic Absorption Spectroscopy
No full textTwo new tetradentate, dianionic N^N-^N-^N ligands combining amido and -extended phenanthridine (benzo[c]quinoline) donors are presented. The coordination chemistry of the ligands was explored via construction of complexes of divalent transition metal Ni(II), Cu(II), and Pd(II) ions. Single-crystal X-ray diffraction confirmed the expected distorted square-planar geometry for examples of each metal, consistent with both ligand-field expectations and the geometric restrictions of the ligand framework. The complexes absorb strongly in the visible region of the electromagnetic spectrum, with steady-state electronic absorption spectra containing a prominent low energy band attributed by time-dependent density functional theory (TD-DFT) to transitions of mixed ILCT/MLCT character, with contributions from dd transitions. Cyclic voltammetry and spectroelectrochemical experiments were used to probe the ability of the new ligand frameworks to support electron-transfer
The influence of age, sex, frailty, and progressive strength training on short-term integrative dynamic cardiovascular and autonomic compensatory responses to orthostatic stress
No full textBackground: The cardiovascular and autonomic systems regulate blood pressure (BP) during postural changes, preventing orthostatic hypotension (OH), linked to dizziness, falls, and mortality. OH is influenced by age, sex, and frailty, yet short-term compensatory mechanisms are underexplored. Aging impairs BP regulation; females show higher OH prevalence due to lower cardiac baroreflex gain (CBG) and greater parasympathetic activity. Frailty further compromises these systems. This thesis includes a systematic review and experimental studies examining whether age, sex, and frailty affect responses to orthostatic stress and if progressive strength training (PST) improves these responses. Methods: Participants underwent two active standing tests: sitting (5 min) or lying (10 min), followed by up to 7 minutes standing. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), cardiac output (CO), stroke volume (SV), systemic vascular resistance (SVR), and HR were measured at baseline, immediately on standing, and throughout four specific phases after standing: phase 1 (0-30s), phase 2 (30-60s), phase 3 (60-180s), and phase 4 (300-420s). CO-SVR matching was evaluated to assess BP regulation timing. Heart rate variability (HRV) at baseline was analyzed in time and frequency domains. CPM was measured by the ratio between HR at the 30th beat and the 15th beat (HR 30:15 ratio) on standing. CBG was determined as the ratio of HR and SBP changes (ΔHR/ΔSBP) at specific phase time points (30s, 60s, 180s, and 420s). Results: This research demonstrated that frail older adults experience greater BP drops and slower recovery after standing, reflecting impaired cardiovascular regulation (Chapter 4). Older adults showed delayed BP regulation, lower short-term compensatory responses, HRV indexes, and CBG compared to young adults (Chapters 5-6). Despite similar BP regulation, older females relied more on SVR and males on CO, with no significant sex differences in autonomic responses (Chapters 7-8). Pre-frail and frail individuals exhibited delayed BP recovery and reduced HRV indexes (Chapters 9-10). Finally, a 12-week PST improved BP regulation timing and countered frailty, though it did not significantly affect autonomic modulation (Chapter 11).
Conclusion: Age, sex, and frailty influence short-term cardiovascular and autonomic responses to orthostatic stress and support PST to enhance BP regulation and counteract frailty in older adults.February 202
Effect of oxalic acid on Varroa destructor and virus replication in honey bees
No full textHoney bee colonies (Apis mellifera) continue to suffer high overwintering losses, with Varroa destructor mites and viruses like deformed wing virus (DWV) recognized as major contributing factors. Effective and timely fall treatments are necessary to reduce Varroa populations before winter without compromising colony health. This study examined the efficacy of oxalic acid (OA) treatments for controlling Varroa mites and their impacts on colony performance and virus dynamics. In the first set of experiments, colonies were treated once in early fall with 3.5% OA trickle, and monitored for changes in mite levels, virus titers, protein content, colony weight, and survival. Although daily mite mortality increased post-treatment, final fall mite abundance was not significantly reduced. However, surviving colonies treated with OA showed lower levels of DWV-A and sac brood virus (SBV) viruses in the spring. Cage experiments revealed that OA alone increased DWV-B levels in the absence of mites. Although it may have had some suppressing impact on block queen cell virus (BQCV), the buffer used for virus inoculation also showed independent virus-suppressing effects.
In the second set of field experiments, we evaluated the frequency, timing and interval between OA vapor applications in late fall and colony performance under different wintering environments. Colonies received zero, one, or four treatments at 2-5 day variable intervals in November in one experiment, and were treated four times either at 5-day or 12-day intervals spanning from September to November or concentrated at the end of the treatment window. Colonies were wintered either indoors or outdoors, and assessed for mite levels, cluster size, colony weight, survival, total protein, and viral load. Colonies treated at 5-day intervals showed better survival then controls for the colonies with low initial mites. While both one and four applications caused mite mortality, only four applications significantly reduced Varroa populations by spring as measured by alcohol wash. Treatments did not directly affect protein or virus levels, but colonies with low initial mite loads had reduced DWV-B levels when treated. Indoor wintered colonies had consistently lower DWV levels than outdoor-wintered colonies. Overall, repeated OA vapor treatments in late fall helped reduce Varroa loads and supported colony survival, but their effectiveness depended heavily on initial infestation levels and treatment timing. These findings highlight both the potential and limitations of OA as a late-season Varroa control strategy.October 202
Validation and implementation of virtual reality serious game for spatial orientation training of older adults with dementia
No full textThis thesis explores the development and evaluation of a serious game in virtual reality (VR) for neurorehabilitation and its associated challenges such as cyber sickness (CS) and benefits including the environmental and behavioral factors affecting motivation and satisfaction in rehabilitation gaming.
The VR environment chosen for neurorehabilitation was a Barn Ruins environment with an embedded game scoring to be used for neurorehabilitation. The study’s objectives included designing an error-based scoring system for Barn Ruins, validating its cognition sensitivity, assessing its potential as a rehabilitation tool through an intervention study, analyzing longitudinal CS data, and identifying factors that influence older adults’ motivation and satisfaction when engaging with serious games.
The Barn Ruins scoring system was found to be suitable for older adults, as it was unaffected by prior experience with gaming controllers. The game score showed a moderate negative relationship with age and a strong positive correlation with Montreal Cognitive Assessment (MoCA) scores. The intervention study revealed significant improvements in spatial learning scores over eight weeks, particularly on challenging routes.
Longitudinal analysis of CS data, spanning 14 years, highlighted age, female sex, and a history of motion sickness as significant predictors of CS susceptibility. Immersive VR environments were more likely to induce CS compared to non-immersive ones, and the use of detailed symptom-reporting methods, such as the Symptom Simulator Questionnaire (SSQ), suggested a potential nocebo effect.
Motivation and satisfaction in rehabilitation gaming were examined through the Unified Theory of Acceptance and Use of Technology (UTAUT) and Cognitive Evaluation Theory (CET). Tailored game design, autonomy, positive interactions, continuous feedback, and community engagement were identified as key factors enhancing user experience.
This research demonstrates the potential of VR-based serious games such as Barn Ruins as a neurorehabilitation tool and offers valuable insights into designing serious games that optimize engagement, minimize cybersickness, and support cognitive rehabilitation.Riverview Health Centre Foundation (co-sponsor for MITACS Accelerate), Graduate Fellowship- Alzheimer Society ManitobaOctober 202
Forced early marriage: Maasai girls' education Kenya
No full textForced child marriage and limited access to education remain significant challenges for Maasai girls in Kenya and is deeply entrenched in cultural traditions and economic factors. In Kenya, 4% of girls are married before age 15, and 23% before age 18. Among the Maasai community in Kenya and Tanzania, over 60% of girls are married off before their eighteenth birthday. Despite the introduction of free primary education in Kenya in 2003, only 48% of Maasai girls enroll in school, and just 10% progress to secondary education. The practice of forced early marriage is primarily sustained by Maasai culture, where girls are often viewed as transient members of their families, to be married off in return for wealth, typically in the form of livestock. This cultural view, combined with poverty and a preference for educating boys, severely limits the educational opportunities available to Maasai girls. The objectives of this study include examining the negative outcomes of forced early marriage on Maasai girls’ education, analyzing how education can prevent forced early marriage and what the government of Kenya should do to help. This study adopts Human Capital Theory by Gary Becker and Theodore Schultz, which asserts that education and skill development are investments that improve individual productivity, income, and life outcomes. Studying employs a qualitative methodology, and the information is examined using Michel Foucault's critical discourse analysis.October 202
Identifying and comparing anticipated and experienced enablers and barriers to implementing an intradialytic cycling program: a multi-method approach
No full textIntroduction: Poor physical function, high symptom burden, and increased cardiovascular risk contribute to poor quality of life and increased mortality in people with kidney failure receiving hemodialysis. Cycling exercise during hemodialysis may mitigate these conditions, but integration of such programs into routine care is limited. Using a new feasibility survey mapped to a behaviour change theory (the Theoretical Domains Framework (TDF)), we identified and compared anticipated enablers and barriers to intradialytic cycling implementation in six hemodialysis units in Canada and Australia participating in an intradialytic cycling trial. We then compared these to enablers and barriers experienced during the trial.
Methods: In this multi-method prospective observational study, the survey was administered to healthcare providers prior to intradialytic cycling implementation between Feb 2023 and Oct 2024. Survey items were deductively coded to eight TDF domains. Proportion of agreement and chi-square/Fisher’s exact tests compared anticipated enablers and barriers by TDF domain within and between study sites, respondent roles and previous unit exercise experience. Experienced enablers/barriers were captured from research staff during monthly check-in meetings and coded to TDF domains (Feb 2023–Apr 2025). Proportion of agreement compared anticipated and experienced enablers and barriers by TDF domain within study sites and within and between units with/without previous exercise experience.
Results: 72 surveys were analyzed. Over 90% of respondents identified anticipated enablers across all TDF domains, most commonly in the domain ‘knowledge’, which demonstrated near-perfect agreement (0.81–1.00) across study sites, respondent roles, and unit exercise experience. Although ‘lack of knowledge’ was also the most identified domain for anticipated barriers, agreement was more variable within and between groups. Overall, when comparing anticipated and experienced responses, enablers were more consistently predicted than barriers. When assessed by study site and unit exercise experience, this difference in capacity to predict experienced enablers versus barriers persisted.
Conclusion: The intradialytic cycling feasibility survey effectively identified enablers but was less consistent in detecting barriers. Further refinement is needed to improve its predictive utility for barriers, incorporate patient perspectives, and assess psychometric properties. This work supports the use of theory-informed tools to facilitate the integration of intradialytic cycling into routine clinical care.October 202
Remission of type 2 diabetes: a mixed-method analysis of lived experience perspectives on barriers and facilitators
No full textType 2 Diabetes (T2D) affects approximately 3.8 million Canadians and is a leading cause of many health complications. T2D remission refers to an HbA1c level 15 kg weight reduction through lifestyle changes and/or bariatric surgery is associated with the greatest likelihood of remission. Although remission rates vary by intervention and individual factors, clinical trials reported estimated remission rates ranging from 30% to 60% of participants. However, few studies explored the lived experiences of those who achieve remission, and the barriers they might experience.
To address this gap, a two-phase explanatory sequential mixed methods study was conducted to explore barriers and facilitators of achieving and sustaining remission through lifestyle interventions. Quantitative data from 21 adult (57±8 years; T2D duration: 4±3 years) with lived experiences of T2D remission were collected to assess clinical outcomes; including health surveys, HbA1c, continuous glucose monitoring (CGM) metrics, and dietary records. From this cohort, a purposive sub-sample of 7 participants took part in a one-on-one semi-structured interviews. An inductive thematic analysis of interview data identified key factors influencing the remission process. Findings were integrated using joint display methodology to explore points of convergence and divergence between clinical indicators and lived experiences.
Analysis revealed that adapting lifestyle behaviors with ongoing self-monitoring and tailoring strategies to individual needs were central to sustaining remission. Quantitative results showed strong glycemic outcomes (mean glucose: 5.0 mmol/L; >92.2% time in range), regular physical activity (Godin Leisure-Time Exercise score ≥ 24), and good perceived health. These aligned with seven overreaching qualitative themes: 1. “flexibility as freedom”, 2. self-reliance, 3. accountability, 4. “one size doesn’t fit all”, 5. “healthcare, not medical care”, 6. barriers inside and out and 7. “I’d rather be healthy”.
Participants reported enhanced physical and mental well-being, crediting self-motivation, accountability, and self-directed education. However, they also reported barriers, including limited healthcare and individualized support, social stigma and mental health challenges, highlighting divergence in mixed findings.
This research contributes to a growing body of evidence supporting lifestyle-based T2D remission and centering lived experience as essential for rethinking and improving T2D care.Research Manitoba Master's Studentship Awards, 2024
University of Manitoba Graduate Fellowship, 2024-25October 202