Honours Theses/Papers

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https://hdl.handle.net/1828/22425

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Modeling medication prescriptions and adherence
(2015) Diemert, Simon
In modern medicine medication prescriptions are one of the primary forms of intervention. Prescriptions are effectively a specification for how to consume a particular kind of substance. A prescription’s complexity can range from a simple verbal orders to intricate sequences of actions that vary depending on a number of different conditions. The adoption of Health Information Technology (HIT) has given rise to electronic prescribing (e-prescribing). Much of the functionality available e-prescribing systems requires that prescriptions be entered in a discrete and well-structured format. Unfortunately, these systems typically only capture a subset of the concepts of prescribing, while the rest of the concepts are entered as free text. The result is poor data quality which affects the quality of the decision support provided by the HIT system. Advances in consumer technology have also allowed for the ability to measure how patients take medications. Such technologies are aimed at addressing the concern of medication adherence, where a patient does not adhere to their prescribed medication regimes. Non-adherence can lead to serious medical problems, and has been identified by numerous authorities and academics as a factor effecting the health care outcomes of both individuals and populations. This thesis attempts to address parts of both e-Prescribing data quality and medication adherence. A Domain Specific Language (DSL) for authoring prescriptions was created. The goal of the DSL is to provide a structured means of creating medication prescriptions that is similar to the natural language expression of prescriptions used by many clinicians. The textual input from the DSL is transformed into a graph model. Once in graph form, the prescription can be manipulated using a computational technique called graph transformation that reduces prescription to a core model. The core model describes the entire prescription in a series of Atomic Prescribed Medication Actions (APMAs). This core model can be thought of as a plan for the prescription. When the core model is combined with the patient’s actual “execution” of the prescription (collected from medication adherence measuring device) the degree of medication adherence can be computed. Using these graph models and transformation systems provides formal definition for the semantics of the prescribing DSL used as input. Such formality provides a means of reasoning about prescriptions in a mathematical way that can then be used to provide feedback and support for clinical and patient users. Supervisors: Dr. Jens Weber and Dr. Morgan Price, Department of Computer Science
Demystifying death: The necessarily expansive role of the end-of-life doula
(2026) Dow, Bethany
This thesis explores the multifaceted role of the contemporary End-of-Life-Doula (EOLD). The increased medicalization of death in the past 100 years has led to an increased need for emotional, mental, spiritual and educational support in end-of-life-care, a gap filled by EOLDs throughout the last decade. Interviews conducted with three EOLDs from the Vancouver Island region confirmed the necessity of this work in supporting people and communities ethically while also emphasizing the need for flexibility in role enactment to fulfill this work. EOLD services span from bedside vigiling to educational roles based in increasing community death literacy and end-of-care planning, yet all facets of care can be understood as being ethically driven by the upholding of individual and community values. The current structure of this work produces a moral economy of exchange between the doulas and their communities, with feminist constructions of care substantiating the work of doulas collectively. While some EOLDs seek a standardization of the role in hopes of decreasing ambiguity and increasing legitimacy of their work, many others argue that this standardization risks a loss in the role’s necessary diversity in practice. This thesis seeks to explain how this loss of diversity poses a threat to the moral economy of death, as the legal boundaries of the practice would inevitably disconnect the ethical basis from this extensive role.
shenKee-yAp (coyote) or shkAkha (dog)? Faunal analysis of a pre-contact canid assemblage from near Lytton in the Mid-Fraser region of BC
(2026) Collins, Lily
This Honours research involves the analysis of pre-contact canid faunal remains recovered during archaeological monitoring near Lytton, BC, within the Nlaka’pamux Homeland. Using current osteometric analytical techniques for canid identification in North America, and in reference to available ethnographic data, this research aims to determine the burial context of the canid assemblage, identify the species of the canids as either coyote (Canis latrans) or domestic dog (Canis lupus familiaris), and better understand human-dog relationships in the Mid-Fraser region of BC. Comprehensive faunal analysis of the assemblage revealed two nearly complete canids. Ethnographic sources revealed compelling evidence for interpreting this assemblage to be associated with both a coyote den and a dog burial. However, species identification was inconclusive due to the fragmentation of the skeletal remains, the limited research on canid identification in North America, and the strong skeletal similarities between coyotes and dogs in the region. The lack of conclusive species differentiation and the ethnographic accounts of interbreeding in the region introduce the possibility that these are coyote-dog hybrids. Definitively identifying the species of the individuals recovered and understanding the context of the burial will require the use of more advanced zooarchaeological or scientific methods. This study highlights the wide-ranging and complex implications of canid identification in the Mid-Fraser. Regardless of whether the assemblage is classified as coyote or dog, this study advances our knowledge of the relationships between humans and canids in Nlaka'pamux communities and highlights the importance of protecting archaeological sites on First Nations reserve lands.
The influence of estrogen exposure on the relationship between mechanical loading and trabecular bone mineral density in young female athletes
(2026) Reed, Finola
Mechanical loading through sport, particularly high-impact activity, and estrogen exposure both promote bone mineral density (BMD). However, excessive training combined with insufficient energy availability can disrupt endocrine function, leading to amenorrhea, low bone mass, and increased fracture risk. Estrogen and mechanical loading influence bone through distinct but complementary biological pathways. Hormonal contraceptives containing exogenous estrogen are sometimes considered protective for bone health in athletes experiencing menstrual dysfunction, though evidence of their effects on bone adaptation to mechanical loading remains mixed. Exogenous estrogen may alter bones’ adaptive response to mechanical strain, yet few studies have examined how estrogen-containing contraceptive use influences trabecular bone adaptation across different loading regimes. Increased awareness of this relationship is important for understanding how hormonal contraceptive use may influence skeletal health in physically active women, particularly those experiencing menstrual dysfunction. This study assesses whether the benefit of mechanical loading to trabecular BMD among young females is mediated by estrogen supplementation in those with and without a history of amenorrhea. Athletes participating in high-impact (soccer and running) and low-impact (rowing) sports were compared with recreationally active controls. Secondary data from peripheral quantitative computed tomography (pQCT) scans were used to assess trabecular BMD at the distal tibia. Significant differences in trabecular BMD between athletes and controls were observed only among women with a history of estrogen-containing contraceptive use, with the effect primarily driven by lower BMD in controls. These findings have important implications for biological anthropology and for advancing understanding of bone health in physically active women.
On Wednesdays we get abortions: How the Abortion Support Collective is increasing and improving access to abortion care on Vancouver Island
(2026) Lee, Alexandra
Despite the legalization of abortion in Canada, many barriers still exist for patients accessing abortion care. Here on Vancouver Island, there is only one abortion clinic offering medication abortion care, and one hospital offering surgical abortion procedures exclusively on Wednesdays, meaning that financial limitations, familial responsibilities, and transportation access can all make abortion care access more challenging for patients navigating an already difficult process. This qualitative research project aims to investigate the specific role of the Abortion Support Collective, a collective of abortion doulas, in making abortion care more accessible on Vancouver Island, through emotional support, resource navigation, and transportation accompaniment. Through semi-structured interviews with abortion doulas and analysis of social media usage, this honours thesis demonstrates the significance that abortion doulas can have in supporting abortion patients, educating the public about abortion care, and increasing and improving access to abortion care in the unique geographical area of Vancouver Island. While abortion access is well-researched within feminist anthropology, there is an absence of research dedicated specifically to the role of abortion doulas, and even less regarding the specific geographical area of British Columbia or Vancouver Island. This research seeks to supplement that gap and add to the available literature on the barriers faced by patients seeking legal abortion care.
Mapping groundwater with geophysics: Locating and characterizing aquifers in the Beaufort Watershed with electrical resistivity surveying
(2023) Yamamoto, Savanna
In the Beaufort Watershed study area on eastern Vancouver Island, groundwater is the primary freshwater supply. More data are needed to improve characterization of the groundwater resource, in order to protect and manage it. Electrical resistivity surveying is a cost-effective remote sensing technique that allows the types of subsurface materials to be inferred, and therefore allow for qualitative and quantitative characterizations of aquifers to be made. Working with the Beaufort Watershed Stewards, I collected, modelled, and interpreted 11 vertical 1D profiles (~83 m deep) and two vertical 2D profiles (81 m long x 17 m deep) in the study area. I was able to distinguish between different types of geological materials such as sand and gravel, till, clay, and various bedrock types and also identify where potential aquifers exist among these materials. Extensive sand and gravel units, which are commonly major sources of groundwater, were only identified throughout the southern part of the study area. Most of these units were determined to be water-bearing, yielding moderate-high quantities of water, and being only partially confined. They had an average thickness of ~17.5 metres, and were all located at ground level. A potential source of groundwater spanning the entire study area was the sedimentary bedrock identified in nearly all profiles, which was determined to be a relatively confined, low-yielding aquifer. This aquifer had an average depth of approximately 32 metres and an undefined thickness. A non-permeable, aquitard unit composed of clay, till, or both was also determined to span the entire region, averaging approximately 30.5 metres thick. The average depth to the aquitard was determined to vary between the northern and southern parts of the study area, where the aquitard in the former averaged roughly 2.5 metres depth, and the aquitard in the latter averaged roughly 18 metres depth. The 2D profiles, on either side of the Ships Point peninsula near Fanny Bay, both indicated the presence of saltwater within a sand and gravel aquifer unit, implying the occurrence of subsurface seawater proximal to shorelines. Supervisors: Lucinda Leonard and Mike Wei
The archaeology of UVic campus lands: Development & cultural heritage management
(2026) Kobrč, Jonáš
Since the recognition of archaeology as a formal discipline in British Columbia, the management and protection of Indigenous archaeological and cultural heritage have been a central aspect of any associated practice, whether academic or professional (in the form of cultural resource management, i.e., CRM). Despite this focus, and BC’s reputation as a leader in heritage legislation, the regulatory system established by the province has been characterized by repeated structural and ethical failures. The system in place has not only failed to recognize Indigenous peoples as stakeholders in their own traditions and culture, and has fallen short in protecting important village and ancestral sites, but in general, an inability to adhere to Indigenous laws, systems of values and international agreements (e.g. UNDRIP). This thesis examines the destruction of archaeological site DcRt-32 within the broader socio-political landscapes of archaeological practice and heritage management throughout BC’s history. Examining the history of this site through ethnographic accounts provided by UVic Anthropology Department faculty members, archival research, critical analysis of heritage legislation and scholarly literature, this study aims to reconstruct the circumstances surrounding DcRt-32’s destruction in 1964. By contextualizing these events through the lenses of heritage management, BC’s evolving systems of archaeological legislation, and a decolonial approach to archaeological practice centered on recognition of Indigenous cultural landscapes and governance, this research posits that the loss of this site was not isolated event, but rather the predictable outcome of a regulatory system built by colonial forces that have long marginalized Indigenous archaeological heritage in the province.
“It’s just what we do in Washabuck”: Community music fostering cultural identity in rural communities of Cape Breton
(2026) Davison, Catherine
This research explores how the rural community of Washabuck, Cape Breton supports the creation of cultural identity through music. The main issue discussed is the barrier central Cape Breton communities face in maintaining Community Music as many of the towns lack easy access to resources, and have declining populations. This research was conducted using interviews and archival analysis. The main results drawn from this research are that community members are making efforts to try and conserve Community Music and cultural identity using foundations such as Treasures of Youth and by creating venues for Community Music to occur. Young musicians need to continue having opportunities to perform, and to have spaces where they feel supported in learning Cape Breton cultural music. This research is significant due to its emphasis on the importance of supporting cultures in rural areas as well as its focus on preserving inclusive, local, community led opportunities that promote Community Music. This research is disseminated through a short film and an accompanying paper.
More stages for better ages: An investigation into the applicability of a seven-stage epiphyseal scoring system in age estimation methods
(2026) Ashdown, Kaitlyn
The process of long bone development - epiphyseal maturation - is a canalized process that progresses through distinct maturational stages at relatively consistent ages across juveniles. Because of this consistency, epiphyseal maturation is a common proxy for chronological age in age estimation methods. Ages at which epiphyses are expected to appear, undergo fusion to the diaphysis (active fusion), and completely fuse to the diaphysis, are well-established. However, age reference standards for these maturational stages can be broad, particularly for active fusion; this is largely because epiphyseal fusion studies commonly combine individuals at all degrees of active fusion into one ‘partial fusion’ stage, thereby limiting the precision of age estimates from these reference standards. In an effort to increase age estimation accuracy, this study investigates the applicability of a precise, seven-stage epiphyseal scoring system developed by Dr. Kyra Stull and Dr. Louise Corron. To do so, this study utilizes a known age-at-death sample of American juveniles aged between 5 and 20 years old and raises the following question: How might Stull and Corron’s (2022) seven-stage scoring system be used to refine epiphyseal age estimation methods? Quantitative descriptive analysis via relative frequency distribution revealed consistent patterns in how individuals progress through active fusion of the humeral and femoral epiphyses. These patterns indicate that narrower, more precise expected age ranges can potentially be produced for use in age estimation methods based on degree of fusion for slower fusing epiphyses. Results of this study can be used to inform further development of precise age estimation methods for American populations.
Hydrothermal vent fluid temperature at Endeavour Segment, northeast Pacific Ocean
(2026) Hodge, Kimberly
Hydrothermal vent fluid temperatures at mid-ocean ridges are highly dynamic and are thought to reflect interactions between seismic activity, tidal forcing, and subsurface permeability structure. However, limited long-term observations make it difficult to resolve the mechanisms driving this variability. Here, we investigate temporal changes in vent fluid temperature at the Endeavour Segment of the Juan de Fuca Ridge, with a focus on the relative roles of earthquakes, tides, and permeability evolution. A ~ 6°C temperature perturbation on March 6th, 2024 is associated with a magnitude 3.6 earthquake, with a smaller precursor signal suggesting foreshock influence. The initial temperature decrease is interpreted to result from increased permeability, promoting fluid dispersion and potential seawater entrainment, while the subsequent recovery is consistent with permeability reduction through mineral precipitation and conduit insultation. In contrast, a gradual ~ 10°C temperature increase over a longer period corresponds to reduced seismicity, suggesting passive permeability decline and increased insulation of fluid pathways, potentially enhanced by anhydrite precipitation. Tidal signals are evident at daily and fortnightly timescales, although their mechanisms remain unclear and may reflect indirect influences such as tidally modulated bottom currents. Irregular temperature fluctuations show no consistent relationship with seismicity or tides, indicating the combined influence of multiple interacting processes within a heterogeneous crustal system. Analysis of mooring data provides no clear evidence for a corresponding plume response to the March 6th event, highlighting the limitations of temperature and conductivity measurements alone. We conclude that vent fluid temperature variability is strongly controlled by site-specific permeability dynamics influenced by both seismic and tidal processes, and emphasize the need for long-term, multidisciplinary observations, including water chemistry, to better constrain hydrothermal system behavior. Supervisor: Casey Brant
Mud volcano imaging using ambient seismic noise
(2021) Goerzen, Chet
Mud volcanoes are a relatively little known geological phenomenon. They are characterized by the extrusion of mud at the earth’s surface. Mud volcanoes represent a serious risk to human life and property, and may also play an important role in the natural greenhouse gas cycle. The Waimata Valley region of New Zealand has been known to have several episodes of mud volcanism. A dense array of short-period geophones was deployed in order to study the subsurface structure of this area. Mud volcano eruptions have occurred many times in the past before the array of geophones was deployed. There was also a mud volcano eruption that occurred several months after the geophone array was decommissioned. Ambient noise tomography was employed in order to study the subsurface structure of the mud volcano by creating a 3-D model of shear wave velocity within the area of mud volcanism. Low-velocity zones were observed in regions underlying the known surface expressions of mud volcanism. An area of mud volcanism that had been dormant since 1930 was observed to correspond to a low-velocity region, suggesting that the source of the mud volcano persists long after an eruption. A low-velocity zone was also observed in the area that later hosted a mud volcano eruption. This suggests that areas of potential mud volcanism may be identified by low-velocity zones revealed by ambient noise tomography. Supervisors: Honn Kao and Lucinda Leonard
Using geophysical methods to constrain the Quaternary activity of the eastern San Juan fault
(2026) Irwin, Danny
Upper plate faults of southern Vancouver Island have hosted Quaternary earthquakes, posing a significant risk to the densely populated regions of Greater Victoria, Vancouver, and Seattle. The San Juan fault lies adjacent to several faults that have been proven active in the Quaternary, yet its activity remains uncertain due to lack of study. I use a recently available wealth of lidar data to carefully map the eastern part of the fault, looking for intersects between fault lineaments and glacial morphological features. I find a site that is easily accessed by vehicle, where a suspected fault scarp is clearly visible in the lidar data, situated in glacial deposits. Either this scarp formed before the till was deposited, or the scarp formed since the deposition, and is due to either dip-slip and/or strike-slip motion. I perform electrical resistivity tomography, relative gravity, and total magnetic field surveys across the scarp at this location to test these hypotheses, with the resistivity profile showing the most decisive results. Fault structures are observed, and disruptions appear in the uppermost layer, with little visible vertical offset in the till bases, consistent with fault rupture in the Quaternary, with the motion being mostly strike-slip. These findings, combined with similar findings from previous studies further west on the San Juan fault, make a compelling case for further work on the fault, and this location, with its ease of vehicular access, presents the ideal setting. Supervisors: Lucinda Leonard and Edwin Nissen
Anatomical and ultrastructural characterization of the frog accessory olfactory bulb and vomeronasal nerve
(University of Victoria, 2026) Merx, Xander
The accessory olfactory bulb (AOB) serves as the central relay for vomeronasal chemosensory information and has been implicated in activity-dependent synaptic plasticity in frogs. Activity-dependent enhancement (ADE), observed at the vomeronasal nerve (VNN)–mitral cell synapse, has been described in Rana pipiens and hypothesized to involve neuropeptide co-release from dense-core vesicle (DCV)-containing afferent terminals. Bimodal compound action potential recordings from the Lithobates catesbeiana VNN suggest the presence of two morphologically distinct axon populations. The present study employed light microscopy, transmission electron microscopy (TEM), and horseradish peroxidase (HRP) anterograde tracing to characterize the anatomy and ultrastructure of the AOB and VNN in adult L. catesbeiana. Light microscopy revealed a laminated AOB with glomerular and mitral cell layers; a notably sparse periglomerular cell population was identified, consistent with the frog AOB being less elaborated than its mammalian counterpart. TEM of the glomerular neuropil identified likely dendrodendritic synapses and gap junctions, features documented in the mammalian olfactory bulb but not previously reported in the frog AOB. Large vesicular profiles with electron-dense cores were observed in HRP-DAB labeled VNN afferent terminals; however, the evidence is insufficient to confirm the presence of dense-core vesicles, and these observations do not provide anatomical support for the neuropeptide co-release hypothesis. Quantitative axon diameter analysis identified two morphologically distinct fascicle types: Type A fascicles with a unimodal small-axon distribution and Type B fascicles with a bimodal distribution with a sparse large-profile subpopulation, consistent with the bimodal CAP profile. These structural observations support ongoing functional investigations and warrant further study using biochemical and volumetric imaging approaches. Supervisor: Dr. Kerry Delaney
Variation in Pseudotsuga menziesii foliar fungal endophyte community composition over a growing season
(University of Victoria, 2026) McCarroll, Callah
Plants host a diverse array of micro-organisms referred to as endophytes, which reside primarily in the interstitial spaces between plant cells. Endophytes often exist in complex communities composed of multiple species from multiple kingdoms, although fungi are the most common colonizers of plant tissues. These micro-organisms interact with each other and with the host, sometimes resulting in altered phenotypes for the host plant which can be beneficial or detrimental. Determining what drives the structure of these community assemblages is a key prerequisite for understanding the overall nature of microbial ecology. Douglas-fir trees (Pseudotsuga menziesii) are a keystone species threatened by disease, climate change, and human development, and like all plants, they harbour a diverse suite of fungal endophytes. In this research, the temporal dynamics of Douglas-fir foliar fungal endophyte communities was systematically characterized over an entire growing season. This was done by collecting Douglas-fir needles from 16 trees in a single location six different times over a calendar year. High-throughput sequencing-based metabarcoding was employed to amplify fungal ITS1 sequences for identification of fungal endophyte community members within Douglas-fir leaf tissue at different times of the year. Using both Alpha and Beta diversity measures, this research was able to show significant community dissimilarity between sampling months. This research also described a dominant unknown endophyte within the order of Mycosphaerellales appearing to have a negative relationship with Nothophaeocryptopus gaeumannii, a well studied Douglas-fir endophyte and causal agent of Swiss needle cast disease. This is the first seasonal description of fungal endophytes within Douglas-fir needles using meta-barcoding analyses. Supervisor: Dr. Jürgen Ehlting
Non-visual opsin expression in the optic tectum of starry flounder (Platichthys stellatus)
(University of Victoria, 2026) Aveyard, Laurel
Non-visual opsins are light sensing proteins that are not associated with the typical image forming process and can be found not only in the retina, but across a wide variety of tissues such as brain and skin. Their expression in the brain specifically has been documented in several species, but the question remains as to whether these proteins are contributing to light sensitivity of the brain itself. The starry flounder (Platichthys stellatus) is a species of flatfish with several ecological and anatomical characteristics that allow for an indirect method of investigating the potential of brain light sensitivity. Because of their asymmetrical anatomy, their brains are located with one hemisphere pointing upwards and receiving more light stimulus than the other. They are found as both left sided and right sided individuals in the wild, meaning investigation of light sensitivity related to the upwards facing hemisphere in a given individual is possible. This study investigated expression of the specific non-visual opsin melanopsin in the optic tectum of the brain, which is the structure responsible for integration of visual stimuli. This was done using an immunohistochemical staining technique with antibodies designed to bind mammalian-like melanopsins. This provided a qualitative analysis of the levels of expression and how they differed between the hemispheres. There was no notable qualitative difference found between hemispheres in terms of expression, however there appeared to be pan-neuronal labelling throughout both hemispheres of the optic tectum. Further research is required to identify levels of protein expression, however this is an indication of melanopsin presence in the starry flounder brain and is a first step in understanding how these proteins may function in this asymmetric species. Supervisor: Dr. John Taylor
Characterization of the sex associated region in the sablefish genome
(University of Victoria, 2026) Carlow-Ujiie, Tasmin
The locus that determines sex in sablefish (Anoplopoma fimbria) and a putative master sexdetermining gene, gsdf, were mapped to chromosome 14 in 2013. In 2021, the role of gsdf was confirmed and the allele responsible for sex was characterized to be a 936 transposable element insertion upstream of gsdf that upregulates expression in developing testis and determines maleness via a male heterogametic (XX/XY) system. According to classical theory of sex chromosome evolution, a sex-determining mutation creating a master sex-determining (MSD) gene is followed by recombination suppression spreading from that locus and eventual chromosome degradation and differentiation which ultimately produces heteromorphic sex chromosomes. In sablefish, it was not clear whether X and Y versions of chromosome 14 differed beyond the gsdf insertion. In this study, we used genome wide association studies (GWAS) and linkage disequilibrium (LD) analyses to define boundaries of the sex-associated region (SAR). We found that loci with genotype frequencies that differed between males and females were distributed across a large region of chromosome 14 (38,000 bp). Genes within this block include LOCI129102360, nup54, LOCI129102793, and gsdf. A weaker male-specific block of LD beyond the SAR included aff1. Alleles of nup54, LOCI129102793, and aff1 on the gsdfY-bearing (Y) chromosome differed nonsynonymously from X-linked counterparts. These genes therefore appear to be ‘founder loci’ of an emerging sex-determining region. Moving forward, characterization of the SAR at this stage of sex chromosome evolution will explicate the rate and progression of the sex-determination system in sablefish. Supervisor: Dr. John S. Taylor
Using ocean gliders to understand the physical oceanography of Fitz Hugh Sound
(2026) Williamson, Martin
Autonomous glider transects from Queen Charlotte Sound (QCS) into Fitz Hugh Sound (FHS) provide high resolution cross-sections of temperature, salinity, density, and oxygen that reveal the dynamics of deep-water renewal and vertical mixing in a deep-silled fjord on the central coast of British Columbia. Glider transects collected between March 2024 and August 2025 were analyzed alongside Hakai CTD surveys to document the timing, structure, and modification of renewal flows. Renewal primarily occurs as a summertime process, with dense QCS shelf water flowing over the Hakai Passage (HP) sill and flushing the FHS deep basin, with an upper layer of FHS water leaving through HP as a return flow. Renewal appears to occur over the HP sill as opposed to the wider southern sill. A temperature - salinity parameter space comparison suggests that weaker winter renewal can also occur, bringing higher oxygen water into the deep basin. Simple two-layer hydraulic control estimates give upper bound flow velocities of 0.6-0.7 ms−1 and volumetric fluxes of 3.6-4.2 × 104 m3 s−1, implying a characteristic deep basin flushing timescale of roughly 15-19 days during renewal conditions. Vertical diffusivity estimates based on conservative tracers yield values on the order of 10−3 m2 s−1, consistent with previous studies in similar British Columbia fjords and waterways. Although source waters on the shelf occasionally reached hypoxic concentrations during the study period, mixing over the sill and along the renewal flow path increased oxygen levels, preventing hypoxia in the FHS deep basin. These results highlight the role of sill mixing in buffering deep fjord basins from hypoxic shelf source water, but also suggest that future declines in oxygen on the QCS shelf could overcome this protection if water of lesser density becomes hypoxic. Supervisor: Jody Klymak
Characterizing the expression of cholinergic neurons within the mouse dorsal subiculum
(University of Victoria, 2026) Girard, Daniel
Acetylcholine (ACh) is a neurotransmitter used for a variety of functions including muscle contraction and neurotransmission between neurons in the brain. Choline acetyltransferase (ChAT) is an enzyme that synthesizes ACh. Using a genetically modified mouse line (ChATcre::ChR2-YFP) allows us to visualize ChAT expression in brain regions due to the co-expression of yellow fluorescent protein (YFP). The dorsal subiculum expressed YFP fluorescence in adult mice, suggesting that this brain region is cholinergic despite previous research claiming otherwise. Using confocal microscopy, this study characterized YFP expression within the dorsal subiculum coupled with ChAT immunolabelling to examine whether this brain region contains cholinergic neurons. Brain sections from six ChATcre::ChR2-YFP mice between 59-95 days old of both sexes were examined. To validate correct YFP expression and ChAT labelling in other brain regions known to contain cholinergic neurons, we immunolabelled and quantified ChAT and YFP positive neurons in the primary visual cortex, the striatum, and medial habenula. We confirmed high YFP and ChAT co-expression from these brain regions. In the dorsal subiculum, we imaged YFP neurons, ChAT immunolabelled neurons, and NeuroTrace labelled neurons. Based on our results, the dorsal subiculum contained very few ChAT positive cholinergic neurons and is therefore non-cholinergic. Despite this, the sparse ChAT-labelling colocalized with YFP expression while the majority of YFP labelled cells did not co-express ChAT immunolabelling, suggesting that ChAT may have been present in the dorsal subiculum prior to adulthood. Future work should examine the subiculum during development to see if ChAT-labelling fully colocalizes with YFP expression. Supervisor: Dr. Raad Nashmi
Melanopsin (opn4) immunolabelling in the zebrafish (Danio rerio) brain
(University of Victoria, 2026) Ma, Isabel G.
Light is an important signal for vertebrates, not only for image-forming vision, but for non-visual roles including development and physiological responses. Vertebrates detect light using light-sensitive proteins called opsins that are paired with a chromophore. Non-visual opsins are found in a diversity of tissues in vertebrates for both mammals, with the fewest opsins, and ray-finned fishes, with the largest opsin repertoires. Many studies have characterized non-visual opsin mRNA in fish brains, especially in the model zebrafish (Danio rerio), and a few studies have delved into the roles of non-visual opsins. Of the non-visual opsins, melanopsin (opn4) is the most well-studied. It has been observed in intrinsically photosensitive retinal ganglion cells (ipRGCs), which have various roles, including in the circadian rhythm, pupillary light reflex, and mood. Melanopsin mRNA has been characterized in the zebrafish brain, and melanopsin proteins have been observed in sablefish (Anoplopoma fimbria) brains. However, until now, no studies have investigated the expression of melanopsin proteins in zebrafish brains. This study uses immunohistochemistry to show melanopsin proteins in the adult zebrafish brain. Melanopsin occurs in two layers of the optic tectum (the superficial white and grey zone and central zone), the torus longitudinalis, large cells in the paraventricular organ, the torus lateralis, the inferior lobe, and the hypothalamus. Presence of melanopsin proteins in the zebrafish brain is consistent with the hypothesis that the brain is intrinsically light sensitive, and localizing the proteins will help direct future studies designed to test the light-sensitivity hypothesis. Supervisor: Dr. John S. Taylor
Modelling bonus seismic wave arrivals recorded on SchoolShake seismographs from the March 2025 Orcas Island earthquake
(2026) Reed, Sedona
In the seismograms recorded at SchoolShake network seismographs across Greater Victoria, BC during the M4.5 Orcas Island earthquake on March 3rd, 2025, a bonus wave arrival was identified between the P and S arrivals at stations within an azimuthal range of 219-256° around the epicenter. Such arrivals had not been previously documented. The focus of this study was to determine the origin of the bonus seismic wave arrivals using seismic ray path and travel time modelling for increasing levels of model complexity. Initial modelling using the 1-D ObsPy.TauPy software successfully reproduced direct P and S wave arrivals but was insufficient to model the bonus phase arrivals. Subsequent 2-D modelling using Pykonal was implemented to better account for the subsurface structure, which includes dipping boundaries such as the top of the subducting Juan de Fuca plate. This modelling demonstrated that a reflection of seismic energy off the Juan de Fuca slab produced arrivals too late to match the bonus arrivals, therefore ruling out this boundary as their origin. Modelling reflections off a shallower boundary, consistent with the highly seismically reflective E-layer, produced arrival times consistent with the actual bonus phase arrivals. Residuals between the observed and modelled arrival times were minimized to lie within ±0.8 seconds across the analyzed stations, providing evidence that the bonus arrivals are consistent with P wave energy reflection off the top of the E-layer. These findings demonstrate the need for more spatially complex subsurface models, such as the 2-D Pykonal model and ideally a 3-D model, to model seismic wave travel in the presence of dipping subsurface boundaries. The bonus phase arrivals may contribute to longer and more intense shaking, which highlights the importance of understanding seismic wave travel to improve local hazard assessment and risk mitigation in Greater Victoria. Supervisors: Camille Brillon and Lucinda Leonard

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