Open Theses & Dissertations

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The feeding habits of wild and domestic felids in New Brunswick, Canada
(University of New Brunswick, 2025-08) Bellamy, Jesse; Hayden, Brian; Nocera, Joe
Domestic cats (Felis catus) are major predators of wildlife and are linked to high mortalities of wildlife species. Despite known conservation risks, feeding habits of free-ranging cats in Canada are understudied. This study used stable isotope analyses to compare the diets of four cat types in New Brunswick, Canada: 1) free-ranging cats, 2) house cats, 3) Canada Lynx (Lynx canadensis) and 4) Bobcats (L. rufus). To quantify diet and trophic niche, the stable isotopes of carbon (13C) and nitrogen (15N) were measured in fur samples of cats and putative prey, including small mammals, birds, and commercial pet foods. There were distinct differences in diet and trophic niche between domestic and wild cats. House and free-ranging cats predominantly consumed artificial foods (>90% of diet), while bobcats and lynx consumed wild prey. There were no credible differences in diet or trophic niche observed between house and free-ranging cats, suggesting high levels of supplemental feeding and human-subsidization of free-ranging cat populations in New Brunswick.
Implementability of a community-based intervention to reduce sedentary time-The EngAge Project
(University of New Brunswick, 2025-08) Daamen, Morgan; Bouchard, Danielle
This study evaluated the implementability of a 9-week home-based intervention to reduce older adults’ sedentary behavior. The main outcome, implementability, was assessed using eight criteria: adherence, adverse events, completion, engagement, dropouts, quality, training, and user satisfaction. It was hypothesized that completers would meet a minimum cut-off of 5/8 tested with a one-proportion test. Secondary outcomes included changes in physical functions and objectively measured sedentary behavior. Forty-two people participated (age 66 to 75; 74% female). Despite a high number of dropouts (n=18), all completers met six or more implementability criteria, 87% met seven (p=0.01), and 52% all (p=0.84). For completers, two out of three physical function tests showed significant improvement (p < 0.05), along with increased daily steps and upright time (p  0.05). Given the small number of resources needed to deliver the intervention and the high proportion of older people with high sedentary behavior, the intervention could be scaled up.
Properties and applications of hydrogen-bond rich iridium (III) complexes
(University of New Brunswick, 2025-08) Jones, Trystan Harri; Blight, Barry A.
Iridium (III) complexes are used for a wide variety of applications owing to their thermal stability, tuneable electronic properties and strong photoluminescent character. Iridium (III) complexes can be structurally altered to change the wavelengths of light they absorb and emit making them desirable for organic light emitting diodes (OLEDs) and photocatalysis. The structural is altered through changing the ligands in the first sphere of coordination surrounding the iridium metal centre. In this thesis we introduce a wide range of iridium (III) complexes all incorporating a ligand with an incorporated hydrogen-bonding array capable of strong non-covalent interactions. These strong noncovalent interactions provide opportunity for modulation of opto-electronic properties through the second sphere of coordination which allows us to further tune these complexes to specific applications. Herein we demonstrate the design and synthesis of a large new series of hydrogen-bonding iridium (III) complexes along with a thorough analysis of each new reported complex’s opto-electronic properties through spectroscopic and computational techniques. In addition, the new series of hydrogen-bond rich iridium (III) complexes were tested against two main applications: tuneable emissive materials and photoredox catalysis. We found that the complex’s dynamic properties with and without hydrogen-bonding compliments demonstrated potential in both applications. Finally, a rudimentary computational screening technique was incorporated to the synthesis of new iridium materials providing improved targeting of new iridium (III) complexes for their optoelectronic properties.
Discovery, functional genomics, and biochemical characterization of the reserpine biosynthetic gene cluster involved in monoterpenoid indole alkaloid biosynthesis and diversification
(University of New Brunswick, 2025-08) Hwang, Jaewook; Qu, Yang
Monoterpenoid indole alkaloids (MIAs) are structurally complex plant metabolites with important pharmacological uses, yet their biosynthetic and evolutionary origins are incompletely understood. This thesis combines biochemical and phylogenomic approaches to dissect MIA diversification across Gentianales. We identify an ancient geissoschizine synthase (GS) biosynthetic gene cluster (BGC) and a segmentally duplicated reserpine BGC in Catharanthus roseus and Rauvolfia tetraphylla, showing the GS BGC originated near the base of Gentianales while the reserpine BGC arose later in the Rauvofioid clade. Biochemical characterization of the reserpine BGC reveals an oxidase–reductase pair (HYC3O/HYC3R) that effects a C3 stereochemical inversion to produce the 3R-MIA scaffold, and these enzymes are conserved across Gentianales. Reconstructing the evolution of these two BGCs demonstrates how genomic architecture and enzyme innovation generate chemical diversity and shows that tissue-specific expression pattern within a BGC may refine alkaloid profiles. These findings broadly advance drug discovery, synthetic biology strategies, and metabolic engineering applications for MIAs.
Influence of contraction intensity on high-density electromyography spatial parameters and motor unit recruitment of the triceps surae during plantarflexion
(University of New Brunswick, 2025-08) Green, Timothy Avery; Kuruganti, Usha
The triceps surae is critical for movement but remains understudied. This study used high-density surface EMG (HDsEMG) to examine spatial features of the triceps surae during isometric plantarflexion. Seventy-four healthy adults (mean age = 22.8 ± 2.0 years) performed isometric contractions with 32-channel electrode grids on the medial and lateral gastrocnemius and soleus. Root mean square (RMS), median frequency (MDF), and coefficient of variation (CoV) were compared across muscles. The gastrocnemii exhibited significantly greater RMS than the soleus at all contraction intensities. The medial gastrocnemius showed significantly greater MDF at higher intensities, suggesting a greater contribution of fast-twitch muscle fibers. The lateral soleus had significantly higher CoV compared to the medial soleus and lateral gastrocnemius suggesting that the lateral placement captured muscle activity from surrounding musculature. Finally, motor unit decomposition was explored, and an open-source dataset was created. These findings highlight important differences in triceps surae recruitment, with clinical and research implications.
Improving simulation with medical task trainers using mixed reality
(University of New Brunswick, 2025-08) Campbell, Cole Kenneth; Bateman, Scott
Medical simulators, such as manikins and task trainers, are commonly used for skill development in nursing education. Existing simulators have tradeoffs in their abilities to simulate physical conditions, support patient communication, provide hands-on skill development, or in their expense. To address these shortcomings, a mixed reality (MR) system was developed, enhancing a medical task trainer with a virtual patient, which was compared against a standardized patient actor (SP). Results indicate that the MR system supported learning as well as the SP, while reducing learners’ feelings of stress. The MR system also improved the ability to recognize a medical emergency based on physical symptoms that the SP could not replicate. Despite the MR system using scripted dialogue, participants practiced their communication skills in a similar manner to the SP. Our work demonstrates the viability of MR simulators for providing simultaneous hands-on skill development, communication, and procedure training in health education.
Spin symmetry breaking in electronic structure theory
(University of New Brunswick, 2025-08) Ayati, Amir; De Baerdemacker, Stijn
In this thesis, two electronic structure methods are proposed that leverage symmetry breaking and restoration at the mean-field Hartree-Fock (HF) level to address the electron correlation problem in molecular systems. A new application of the Generator Coordinate Method (GCM) is presented as an electronic structure method for strong electron correlation in molecular systems. We identify spin fluctuations as an important generator coordinate responsible for strong static electron correlation that is associated with bond-breaking processes. The continuous manifold of basis states for the Hill-Wheeler equations is constructed from spin-constrained Unrestricted HF (c-UHF) states, which is converted into a non-orthogonal configuration interaction (NOCI) expansion. The method was tested on two-electron systems that are dominated by static and/or dynamic correlations. The spin-projected constrained-unrestricted-Hartree-Fock (SPcUHF) method is also introduced. This approach restores the broken spin symmetry inherent in c-UHF determinants by projecting possible configurations derived from a Clebsch-Gordon recoupling scheme in the spin space and including them in a NOCI basis. Our proposed SPcUHF method recovers missing static correlation and significantly reduces computational costs of full projection without compromising accuracy. When combined with a NOCI-PT2 correction, SPcUHF effectively captures both static and dynamic correlations, offering a robust solution for a wide range of molecular systems.
Investigation of the biosynthetic pathway of spiroooxindoles in Hamelia patens and Cephalanthus occidentalis
(University of New Brunswick, 2025-08) Seveck, Alyssa; Qu, Yang
Cytochrome p450 monooxygenases (CYPs) are a vast family of enzymes that play key roles in the biosynthesis of specialized metabolites. They are crucial catalysts involved in numerous biosynthetic reactions such as hydroxylations and oxidations. Monoterpenoid oxindole alkaloids (MOAs) are a subclass of monoterpenoid indole alkaloids (MIAs) and have known medicinal benefits. However, due to their low natural abundance and structural complexity, obtaining them in large quantities for study has been difficult. In this study, I purified and analyzed seven MOAs from Hamelia patens. I also identified and characterized a CYP responsible for catalyzing the oxidation of 3R heteroyohimbine-type MIAs to their MOA derivatives in Cephalanthus occidentalis. This discovery enables the de novo biosynthesis of major MOAs in C. occidentalis. The elucidation of this CYP and MOAs provides valuable insights into the enzymatic biosynthesis of MOAs and can enhance the production of these MOAs for future studies.
Worry, community support service awareness and help-seeking attitudes/behaviours in older Canadian adults
(University of New Brunswick, 2025-08) Finnamore, Ardith; Edwards, Jonathon
This study examined the worries, community support service awareness (CSSA) and help-seeking attitudes/behaviours (HAB) of Canadian adults ages 50 and older. Many researchers have studied the etiology of worry; however, previous studies have not examined the interaction of CSSA and HAB with the worries of aging Canadians. Participants (n=112) completed questionnaires measuring the types and frequency of worry and CSSA. Follow-up interviews about worry, CSSA, and HAB (n=20) were also undertaken. The MANOVA analysis indicated that the overall model was insignificant (V = .03, F(3,103) = 1.19, p = .317). The qualitative analysis resulted in 12 subthemes categorized in the themes Supports, Financial and Health. The theme with the most participant quotes was Supports. The subthemes that received the highest responses were Retirement Savings and Unemployment, and Job Insecurity, both of which are part of the financial theme.
Understanding and supporting long-form text in Mixed Reality
(University of New Brunswick, 2025-08) Brett, Colin A.; Bateman, Scott
Mixed reality (MR) technology provides advanced spatial computing and display capabilities, yet its implications for reading and navigating long-form text are not well understood. This thesis investigates, through two controlled studies, how MR can support central aspects of the medium: sustaining deep, focused reading experiences and enabling efficient navigation within long-form documents. The first study examines user experience and flow state when reading narrative text in MR. The second explores MR capabilities for spatially organized navigation in long-form documents compared to conventional approaches. Through these studies, this work demonstrates that current MR headsets can support immersive reading experiences, and that spatial navigation systems significantly reduce task load while improving speed and usability. These findings highlight the importance of designing for human factors and how spatial metaphors can inform the development of more effective and engaging MR reading and navigation systems.
An experimental investigation into the dynamics and sensor feedback integration of an actively controlled three-dimensional turbulent wall jet
(University of New Brunswick, 2025-08) Titus, Zachary M.; Hall, Joseph W.
An experimental study is presented on the active control of a three-dimensional turbulent wall jet at Re = 137 000 using eight independent synthetic jet actuators. This investigation develops a sensor feedback control approach that enhances the lateral growth beyond what has previously been reported. Changes in the unsteady wall pressure field and the two-dimensional velocity field at y/D = 0.5 are explored in response to the variation of a single phase-angle between the synthetic jet array. These findings are used to develop a genetic algorithm-based feedback control approach with four independent phase-angle inputs. Changes in the unsteady wall pressure field linked to the development of large-scale structures are identified and integrated into the control approach, which resulted in an increased lateral growth of up to 170%, 30% greater than the previous optimal lateral growth. New development, including instances of the potential core splitting and bifurcation are additionally presented.
An efficient evidence-based Automated Fact Checking system
(University of New Brunswick, 2025-08) Dharmavaram, Arbaaz; Hakak, Saqib
The rapid spread of fake news, accelerated by Generative AI, has outpaced traditional fact-checking, overwhelming journalists and verification platforms. Addressing this, we present Sanctuary, an efficient automated fact-checking system using moderately lightweight, open-source language models within a hybrid Retrieval-Augmented Generation framework that grounds its reasoning in retrieved evidence. Unlike approaches reliant on costly proprietary models or basic classifiers, Sanctuary delivers competitive accuracy and robust reasoning, verifying real-world claims in under 30 seconds. In the Fact Extraction and Verification 2025 competition, Sanctuary ranked 3rd, outperforming several systems and the baseline. We also introduce FactCellar, a dataset of real-world claims in realistic retrieval settings, enriched with source credibility and potential impact annotations. Experiments show these metadata substantially improve verification accuracy. Together, Sanctuary and FactCellar advance scalable, transparent fact-checking, offering professionals and everyday users practical tools to counter misinformation.
Adapting forest management to climate change in the Acadian forest region: A strategic modeling approach
(University of New Brunswick, 2025-08) Albert, Cédric; Taylor, Anthony; D’Orangeville, Loïc
Climate change will impact forest dynamics in the Acadian forest region, necessitating adaptive strategies for sustainable forest management. This dissertation examines the impacts of climate change on forest dynamics and management using inventory data from the 5th Canadian Division Support Base Gagetown and climate projections from the IPCC Fifth Assessment Report (RCP4.5 and RCP8.5). Climate-sensitive tools were integrated into strategic forest planning across three interconnected studies. The first chapter synthesizes projected climate scenarios and their implications for New Brunswick’s forests, providing a reference for climate variables and their expected impacts. By 2071–2100, increases in temperature and growing degree days, along with reduced summer water balance, are expected to intensify disturbances such as fires and pest outbreaks. Boreal species like balsam fir and black spruce are projected to decline, while temperate deciduous species such as red maple and American beech are expected to expand. Adaptive silviculture strategies: assisted migration, thinning, and innovative harvest methods, are discussed to enhance forest resilience. The second chapter presents a method for integrating climate-sensitive yield tables and transition rules into strategic planning using the PICUS stand model and the Woodstock landscape model. A rotation-age–based planning approach was used. Simulations under different climate scenarios show a shift toward warm-adapted species, declines in cold-adapted species, and reduced merchantable wood volume, posing economic and wood supply risks. This underscores the need to integrate climate change into forest planning to avoid overharvest and ensure long-term resource availability. The third study assesses climate change impacts on treatment scheduling, wood supply, economic returns, and harvesting practices. Climate-sensitive yield tables and transition rules were developed for two partial-cutting silvicultural interventions. Using linear programming in Woodstock, treatment schedules were optimized to maximize stumpage revenue under three climate scenarios. Clear-cutting remained dominant, but high- and low-retention harvesting increased under warming. A major shift from conifer to deciduous dominance occurred, yet partial cutting mitigated revenue losses. This highlights the value of a diverse, climate-adapted silvicultural toolbox to help buffer negative climate impacts on forest management.
Land dispossession and economic marginalization: The consequences of the Indian Act on Indigenous land rights in New Brunswick from 1876-2013
(University of New Brunswick, 2025-08) Manu, Nicholas Osei; Tozer, Angela
This thesis examines the enduring consequences of the Indian Act on Indigenous land rights and economic marginalization in New Brunswick from 1876 to 2013, with a particular focus on the Elsipogtog Blockade. It integrates interdisciplinary literature on Indigenous populations and the Canadian State alongside a review of key legislation that frames the relationship. It explores how the implementation and amendments of the Indian Act have contributed to the dispossession of Indigenous lands, restricted economic opportunities, and undermined traditional governance structures. The study highlights the lasting impacts of forced relocations, land expropriations, and discriminatory policies on Indigenous communities and Elsipogtog in particular, leading to social dislocation and economic challenges. By contextualizing the Elsipogtog Blockade within this historical narrative, this research underscores the urgent need for reconciliation and redress for Indigenous peoples in New Brunswick.
Risk factors for Internet Gaming Disorder (IGD): Towards lower-risk guidelines
(University of New Brunswick, 2025-08) MacQuarrie, Amy Lynn; Brunelle, Caroline
Internet Gaming Disorder (IGD) and Gaming Disorder were formally added to the Diagnostic and Statistical Manual of Mental Disorders (5th edition) and the International Classification of Diseases (11th edition) in 2013 and 2018 respectively (APA, 2013; WHO, 2022). Prior research has suggested that there are a variety of risk factors for IGD including using video games as a coping mechanism, the presence of mental health and substance use symptoms, and frequency and duration of gameplay (Bussone et al., 2020; Coëffec et al., 2015; Gao et al., 2022; Turner et al., 2012). However, although multiple studies have examined risk factors for IGD, there is currently no research examining the cumulative impact of risk factors on IGD and a lack of attention to gaming-related harms. The present study recruited N = 738 adult (18+) participants who resided in the USA or Canada and had played video games within the past month to participate in an online survey hosted on Qualtrics. Results from prevalence ratio analyses and independent samples t-tests indicated that increased internalizing symptoms, playing games daily and for more hours in a week, playing online games, and playing games for advancement-related or escapism motivations emerged as notable risk factors for IGD and experiencing moderate or greater gaming-related harms (e.g., work or study, health). There was a cumulative effect of risk factors on prevalence of IGD and gaming-related harms. As more risk factors were endorsed, participants’ prevalence of IGD and gaming-related harms increased. These findings provide support for the importance of considering a wide range of risk factors for IGD and may be useful for informing future lower-risk guidelines and public health approaches to IGD.
Eco-emotions and narratives of salmon grief on the Main Southwest Miramichi River, New Brunswick
(University of New Brunswick, 2025-08) Jean, Christine; Tubb, Daniel
Drawing on ethnographic participant observation and eight semi-structured interviews, this thesis focuses on eco-emotions and narratives of salmon grief on the Main Southwest Miramichi River, New Brunswick. As salmon disappear, so does a way of life. To understand how people feel about this, this thesis draws on the literature on eco-emotions and emotional distress caused by environmental loss. In three substantive chapters, it addresses narratives of crisis, narratives of frustrations with salmon governance, and narratives of salmon grief and acts of care. The conclusion highlights the need to view species loss as an emotional issue, and advocates for conservation efforts to support human-salmon traditions, relationships, and ways of life.
MU-MIMO HAP architecture using symbol wavelengths and spread-spectrum delay multiplexing
(University of New Brunswick, 2025-08) Lubaba, Samiha; Petersen, Brent R.
This thesis analyzes a hybrid architecture that integrates spread-spectrum delay multiplexing (SSDM), and symbol-wavelength-spaced antennas to enhance capacity, and mitigate multi-user interference (MUI) in High Altitude Platform (HAP) communication systems. The optimal spatial decorrelation in line-of-sight (LOS) channels is achieved by an odd value of spreading factor, and symbol-wavelength-spaced antennas as evidenced by the analysis of determinant, norm, and condition number. Symbol-wavelength-spaced antennas and spread spectrum delay multiplexing are combined to evaluate their impact on system capacity, interference, and spectrum efficiency. To determine the stability, and effectiveness of the system, the study analyzes important performance measures, such as determinants, norms, and condition number. To enhance signal quality, and reduce multi-user interference, a zero-forcing approach is used. The results demonstrate that antenna spacing at symbol-wavelength intervals provides the best performance, especially in LOS communication situations.
Petrology, mineral chemistry and geochronology of the Eagle, F.D. no. 5, and Tappy pegmatites: Cat Lake-Winnipeg River Pegmatite Field, southeastern Manitoba, Canada
(University of New Brunswick, 2025-08) Roush, James H.; McFarlane, Chris; Martins, Tania
The Eagle, F.D. no. 5, and Tappy are spodumene-bearing, Li-Cs-Ta (LCT) class, rare-element pegmatites. The Eagle and F.D. no. 5 dykes are spatially related: both located in the Cat Lake-Maskwa Lake pegmatite district in the northern part of the Bird River Domain in southeastern Manitoba. However, petrologically and chemically they do not appear to be part of the same body. The Tappy pegmatite is hosted within the Winnipeg River pegmatite district to the south. All three dykes are emplaced near vertically and have good exposure with accessible locations near roads making them all prospective targets for critical mineral development. U-Pb geochronology on tantalite and monazite gives near contemporaneous ages for the Eagle, F.D. no. 5, and Tappy dykes at ~2650 Ma, placing them all within the D3 deformation event in the Bird River, coeval with widespread granitic magmatism and other pegmatites in the region.
“Sometimes There’s a Grey Zone”: Exploring psychologists’ performance validity beliefs and practices
(University of New Brunswick, 2025-08) Wright, Jenna L.; LaChapelle, Diane
Background: Performance validity measures were developed to detect noncredible performance during cognitive assessment. Although these measures were first developed for use in the context of litigation or disability claims, more recent research has shown performance validity also impacts the results of cognitive assessments in situations without obvious financial motivation (Green, 2003; McWhirter et al., 2020; Rohling et al., 2002; Roor et al., 2023). As a result, current practice guidelines recommend the inclusion of multiple embedded validity indicators (EVIs) and standalone performance validity tests (PVTs) in every cognitive assessment (Bush et al., 2005; Heilbronner et al., 2009). Since the publication of these recommendations, surveys have shown a marked increase in PVT/EVI adoption by neuropsychologists (Martin et al., 2015). Nevertheless, little is known about the adoption of PVTs and EVIs outside of neuropsychology and the use of quantitative surveys prevents exploration of how psychologists make decisions about assessing performance validity in ambiguous or challenging situations. Objectives: To address these limitations, this qualitative study explored psychologists’ use of, and beliefs about, performance validity assessment. Also examined was how this real-world use compares to the guidelines provided by professional organizations. Method: Semi-structured interviews were conducted with 25 Canadian psychologists whose clinical practice focused on cognitive assessment. Information gathered during the interviews was examined using content and thematic analyses. Results: Performance validity measures were used less frequently among our participants than in previous survey studies. Participants’ choices to use performance validity measures were influenced by training, contextual factors, emotional reactions to performance validity assessment, faith in clinical judgment, perceived benefits of performance validity assessment, and practical considerations. Markedly variable practices were reported in terms of performance validity measure selection, the number of measures used, and how results are interpreted. The reported practices were only partially consistent with professional practice recommendations. Conclusions: The results suggest training in performance validity is essential to address barriers to performance validity assessment within and outside neuropsychology, as well as to increase consistency in practices across psychologists. Training should prepare psychologists to navigate the ambiguities inherent in assessing performance validity.
Empirical assessment of the temporal transferability of landcover-bird abundance models
(University of New Brunswick, 2025-08) Bamgboye, Oluwagbeminiyi Oluwaseun; Houlahan, Jeff
Despite the widespread use of land cover in modeling species abundance, its predictive reliability over time is not well understood. This study examines the temporal transferability of land cover-based models using Breeding Bird Survey data for 42 U.S. bird species and land cover variables from the United States Geological Survey National Land Cover Database (USGS NLCD). Generalized linear models (negative binomial) were trained on 2001 data, incorporating 14 land cover classes across six spatial scales (200– 3000 m). Model selection via AIC involved consideration of over 3,000 models per species. Land Cover Models outperformed null models in both training and test sets for 28 species, with predictive accuracy improving by 3%–30%. Model performance remained stable from 2004 to 2019, demonstrating strong temporal transferability. While species like the American Goldfinch showed consistently low errors, others like the Bald Eagle performed poorly. These findings highlight the importance of evaluating predictive consistency over time in biodiversity monitoring models.

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