Graduate Theses & Dissertations

Pages

Using automated radio-telemetry to link food availability, reproductive success, and habitat use of Barn Swallows (Hirundo rustica erythrogaster)
Drivers of North American Barn Swallow population declines are not well understood, but foraging habitat loss is thought to be a contributing factor. Determining patterns of habitat use is challenging for swallows because they move rapidly but are too small to carry GPS tags. We showed that automated radio-telemetry could be used to track the movements of swallows with enough accuracy (median error 250 m) to monitor local habitat use. We then combined information on breeding Barn Swallows habitat use, land cover, aerial insect abundance, and fledging success to test for a link between foraging habitat quality and reproductive success. Foraging activity was concentrated within 600 m of nest sites and varied with land cover; however, responses to land cover were not consistent across birds. Aerial insects were most abundant near wetlands and least abundant near open water and over cropland. Consistent with a link between foraging habitat and reproductive success, nests in barns with more wetland and less open water within 1 km, and with less field area within 2 km occupied by row crops, on average fledged more young swallows. Author Keywords: aerial insectivores, automated telemetry, habitat use, land cover, movement, nest success
Using a real-world chopping task to study motor learning and memory
Typically task interference is studied using reaching adaptation tasks (visuomotor rotation and/or force-field learning). Participants in these experiments are already experts at the base task (point-to-point, planar reaching) and their ability to adapt reaching to the imposed perturbation is studied. The pattern of data induced by the perturbation is used to make inferences about the nature and neural correlates of our learning and memory for reaching perturbations, specifically, and motor performance in general. We wanted to see if it is possible to demonstrate this same interference pattern using a novel vegetable-chopping task, where we can easily recreate natural performance settings using a task for which we can easily identify non-experts. Participants performed a chopping task in which they are asked to chop a sweet potato into 5 mm-wide slices, matching the beat of a metronome (120 bpm). Following this initial learning, participants were exposed to an interference condition. Participants then performed trials of the original task again. Interference was inferred if the second performance of the original task was impaired, compared to initial performance. Experiment 1 involved novice choppers, and either the force or frequency of chops was manipulated. Only the altered frequency task produced interference effects. In Experiment 2, competent and expert choppers had to manage either a faster or slower frequency. We found evidence for interference in competents, but not experts. These results support the idea that the vulnerability to interference of motor memory changes with practice, and so any inferences made about memory structure must take into account not only expert performance, but every level of skill. Author Keywords: expertise, interference, motor learning, reaching adaptation
Using Fluorescent Carbon Dots for Biosensing Applications of Amino Acids
Amino acids make up proteins, which are the building blocks of life. A balance of amino acids is needed to maintain a healthy state. Tyrosine (Tyr) is synthesized from the metabolism of phenylalanine, which is an essential amino acid, meaning it can only be obtained from the diet. It is related to many metabolic and neurodegenerative diseases. Tyr can undergo post-translational modifications such as phosphorylation and nitration, which are implicated in cancer and nitrative stress, respectively. Although there are many methods to detect Tyr and its analogues, phosphotyrosine (pTyr) and nitrotyrosine (nTyr), these methods are time-consuming, involve expensive instruments and involve tedious process. This research proposes a new type of nanomaterials, carbon dots (CDs), to detect these amnio acids. Data indicate that CDs can be used to detect nTyr with a limit of detection of 34 μM in the linear range of 20 - 105 μM. The amenability of CD-nTyr assay was also tested in various biological matrices and biological molecules and was shown to be sensitive to nTyr. Nitration of Tyr was carried out in the presence of sodium nitrite and hydrogen peroxide catalyzed by either Cu(II) or Fe(III) to mimic biological reactions and CDs were tested as both inhibitors and indicators of Tyr nitration. Although CDs did not inhibit the nitration reaction of Tyr, they did not serve as indicators of Tyr nitration due to the quenching of CDs by the nitrating agents. This shows the importance of using CDs to detect nTyr and further use it for biological applications to detect diseased states. Author Keywords: amino acids, carbon dots, nanomaterials, sensor, spectroscopy, tyrosine
Using DNA Barcoding to Investigate the Diet and Food Supply of a Declining Aerial Insectivote, the Barn Swallow (Hirundo rustica)
Barn Swallow (Hirundo rustica) populations have declined in North America over the past 40 years and they are listed as Threatened in Ontario, Canada. Changes in the food supply have been hypothesized as a potential cause of this population decline. I used DNA barcoding to investigate the diet and food supply of Barn Swallows and to determine if the food supply affects their reproductive performance. In two breeding seasons, I monitored nests, collected fecal samples, and monitored prey availability by collecting insects from the habitat surrounding breeding sites using Malaise traps. I used DNA barcoding to identify insect specimens collected from the habitat and to identify prey items from Barn Swallow nestling fecal samples. I found that Barn Swallow nestlings were fed a very broad range of prey items but were fed larger prey items more frequently. Prey availability was not related to the timing of reproduction, the number of nests at a breeding site, or the reproductive output of individual nests. This study provides information on the diet composition of Barn Swallows in North America and suggests that food limitation during the breeding season may not be a major factor in their population decline. Author Keywords: aerial insectivore, diet, DNA barcoding, Hirundo rustica, metabarcoding, reproductive success
Use and Utilization of Loose and Commingled Human Dental Remains in Investigations of Ancient Human Populations
Commingled teeth present a unique opportunity for a novel application of standard methodological approaches commonly utilized in dental anthropological studies. Unfortunately, little research has been conducted on loose or commingled dental assemblages to determine if they are suitable samples for reconstructing bioarchaeological narratives of ancient human populations. The lack of research on commingled dental samples is surprising, given that teeth are highly resistant to post-depositional deterioration and are often some of the only remains left in high deteriorated burials. An experimental analysis of a commingled dental assemblage recovered from four chultuns at Ka'kabish, Belize, was conducted to address this lack of research and provide a real-world example of the potential use and utilization of commingled dental assemblages in investigations of ancient human populations. Author Keywords: Anthropology, Belize, Commingled, Dental, Maya, Methods
Use Of Rapid Amygdala Kindling With Corticosterone Supplementation As A Model Of Epilepsy-Depression Comorbidity
Temporal lobe epilepsy increases risk for developing major depression, and conversely, depression increases risk for development of epilepsy. The mechanisms responsible for the widely observed bi-directional relationship between epilepsy and depression are currently poorly understood. One reason why our understanding of shared etiology has had little improvement is due to the lack of availability of a reliable animal model for inducing depression in epileptic animals. The development of a reliable model of epilepsy-depression comorbidity would greatly improve the ability to mechanistically evaluate shared pathophysiology between the conditions. Recently there has been evidence that rapid kindling of the basolateral amygdala can evoke a behavioural phenotype that is comparable to the symptoms of anxiety and depression observed in depressed epileptic patients. However, this work has yet to be replicated, leaving question as to whether or not the behavioural phenotype can be reliably evoked. In the following series of experiments we assessed rapid amygdala kindling as a potential model of epilepsy-depression comorbidity and sought to improve the model with inclusion of the glucocorticoid corticosterone. Our findings may improve our understanding of the unique relationships between epilepsy and depression. Author Keywords: animal models, depression, hippocampus, kindling, stress, temporal lobe epilepsy
Untitled (dissertation 4.2)
Untitled (dissertation 4.2) offers a performative take on the political implications of digital archives. I argue that technological developments and their increasing ubiquity has not resulted in more reliable archives; it has facilitated the exacerbation of what Jacques Derrida calls mal d’archive—or archive fever—which refers to the institutionally supported passion to preserve that is perpetually threatened by the inevitably of loss. A performative perspective, specifically derived from the work of contemporary performance theorists and artists, affords a contemporary archival practice that not only accepts, but is informed by mal d’archive because it shifts the focus from what is preserved to how it has become and continues to be preservable through archival acts. This is important in our contemporary moment because the ubiquity of digital technologies has exacerbated the symptoms of mal d’archive: a rapid increase in both the formal and informal production of preservable content, and consequently, as Derrida reminds us, archival violence. Untitled (dissertation 4.2) also includes a performative engagement with mal d’archive through two interludes. The first interlude features what I am calling “glitch-utterances,” which refers to the visual representations of technological mishaps. The documents in the second interlude—an iteration of the exhibition catalogue that resulted from my 2020 artist residency at the Art Gallery of Peterborough—engage with the productive function of the archive because they performatively constitute the exhibition as having happened regardless of whether or not it actually occurred, which, significantly, it did not. I conclude Untitled (dissertation 4.2) with a look at the ecological impact of digital archives—perhaps an “ecological fever.” It is not my intention to offer a solution for this “ecological fever,” nor address its full impact. My aim is to conclude this dissertation with a supplement of sorts: a look at the ecological impact of digital archives because I feel it is irresponsible not to given their increasing ubiquity. With this in mind, the glitch-utterances featured in both interludes can perform an important role in calling attention to the technological materialities and computational processes that are rendered invisible by Big Tech companies via metaphors—the ethereal Cloud metaphor, for example. These glitch-utterances point to the very material substrates that support the virtual, and can thus act as an important reminder of the ecological consequences of digital archives, which, like archival practices, are tied to institutional agendas. Author Keywords: Archive , Curation , Digital Archive, Documentation, Multimedia performance, Performativity
Unsettling Inner Landscapes
Recent climate scientists, Indigenous resurgence scholars, and psychologists have variously indicated that we need a transformation of consciousness in order to address the cultural and spiritual forces at the root of our current environmental, interpersonal, and individual crises of disconnection. My research is in direct response to diverse calls for this paradigm shift, including the words of Elders such as the late Grandfather William Commanda who encouraged settlers such as myself to ‘remember our original instructions’. Through an anti-colonial and trauma-informed lens, my goal has been to strategically inform my roles and responsibilities in healing the disconnection and abuses in what I term the trilogy of my relationships to self, others, and Land. This study is both a critical auto-ethnography and as well as a theoretical engagement with Indigenous resurgence, settler colonialism, and sustainability discourses. I share dialogues with Anishinaabe-kweg in my community with whom I have established relationships and the results of our discussions focus on holistic models of transforming settler consciousness. What emerges is an emotional, uncertain, and yet radically hopeful narrative that points to the urgency of centering Indigenous sovereignty and Indigenous relationship models while endeavouring to reconstruct a sense of identity and belonging along more accountable lines. Recovering a sense of my Celtic epistemology and story work is offered as a strategic exemplar of how settlers might begin to remember and co-create more balanced, respectful, and reciprocal relationships with and within place. Nurturing an embodied spiritual practice of deep listening, critical self-reflection, and collective action is discussed as potentially central to sustaining a decolonizing praxis for white settler Canadians more broadly. Author Keywords: Critical auto-ethnography, Critical Spirituality, Decolonization, Indigenous-settler relations, Original Instructions, Settler colonial studies
University Aged Millennials' Attitudes and Perceptions Toward Vehicle Ownership and Car Sharing
Car-sharing may have the potential to contribute to a more sustainable transportation system. The current research sought to answer the question: what are university-aged Millennials' perceptions and attitudes toward the adoption of vehicle sharing and private vehicle ownership? The research consisted of hosting six interactive focus group sessions with Millennial students, who currently do not own vehicles. Using a qualitative approach, I analyzed the discussions through a social practice theory lens. I suggest that skills, meanings, materials, and social interactions have an influence on the way in which a transportation option is perceived by Millennials. The results revealed that social norms surrounding vehicle ownership and car sharing are being developed, shaped, changed, challenged and reconstructed. If car-sharing businesses, universities, and governments wish to progress toward a more sustainable transportation system, they should recognize the importance of marketing. Author Keywords: Car ownership, Car sharing, Millennials, Sustainability, Transportation, University
Union Organizing in the Canadian Banking Industry, 1940–1980
In this dissertation, I examine union organizing in the Canadian banking industry between 1940 and 1980. By demonstrating that bank workers consistently sought to unionize throughout the twentieth century, I challenge claims that bank employees and other private sector white-collar workers have low rates of unionization because they are not interested in unions or suffer from false consciousness. This research also suggests, however, that many bank workers saw themselves as different from blue-collar industrial workers; the lived reality of bank work as precarious, poorly paid, and rife with gender inequality intersected with ideas about professionalism and aspirations of advancing up the career ladder. Banks, unions, and workers drew on these ideas and experiences in their arguments for and against unionization. I also look at why previous organizing efforts did not establish a strong union presence in the banking industry. Most of these attempts failed, I argue, due to several key issues, including the banks’ anti-union activity, federal and provincial labour board decisions, and labour movement disputes over ideology, jurisdiction, and strategy. The banks consistently opposed unionization and used a variety of tactics to thwart union organizing, both overtly and covertly. The state, in the form of labour legislation and labour boards, provided unions and workers with some means by which to compel the banks to recognize unions, negotiate contracts, and deal with employee grievances; however, state action and inaction more often worked to undermine union organizing. The attitudes and strategies of high-ranking labour movement officials also shaped the outcome of union drives in the banks. Between 1940 and 1980, the mostly male labour leadership repeatedly used top-down organizing strategies and appointed male organizers with no experience of bank work to oversee union drives in a sector with an increasingly feminized workforce; labour leaders’ inability or unwillingness to reflect on this approach and to support grassroots campaigns and alternative strategies hindered bank union organizing. I thus highlight the intersection of gender and class and reveal how these factors have historically shaped the labour movement bureaucracy, union organizing, and the relationship between labour and the state. Author Keywords: banks, gender, labour bureaucracy, trade unions, union organizing, white-collar workers
Unexpected Journeys
The last two decades have seen thousands of Canadian university graduates go to teach English in places such as China, South Korea, and Japan. In this thesis, drawing on Clandinin and Connelly's concept of narrative inquiry, I situate the stories I heard about the experiences of 15 teachers who taught English as a Second Language in South Korea between 2003 and 2012. While my interviewees expressed intrinsically personal reasons for taking on such temporary professional employment, they also acknowledged that they felt somewhat forced to do so by an increasingly bleak job market at home. I position their decisions in the neoliberal employment context in Canada over the past two decades, highlighting the personal and socioeconomic factors that influenced them to take up such opportunities. Additionally, I examine how these experiences shifted their views of Canada and what it meant to be Canadian, both while they were away and upon their return home by revealing the contradictions between expectation and the lived realities of young Canadians. These contradictions unmask the deceptive nature of dominant narratives in Canadian society. Author Keywords: Canadian Identity, Canadian Job Market, Narrative, Neoliberalism, Teaching Abroad
Understanding the establishment of Typha spp. in North America using population genetics and common garden studies
There are three cattail (Typha) taxa in Canada: T. latifolia (native), T. angustifolia (introduced), and their hybrid T. x glauca. The latter is invasive in regions around the Laurentian Great Lakes, and I investigated the potential role that commercial suppliers may be playing in the introduction of non-native Typha by comparing genotypes of North American, European, and commercially available plants. I found that Ontario garden centres are importing both hybrids and non-native lineages of T. angustifolia into Canada, but was unable to identify the provenance of T. latifolia. I also investigated the possibility that the hybrid cattail leaf litter shade and leachate influences germination and early growth of the parental species of the hybrids. Using three common garden experiments, I found that T. x glauca leaf litter suppresses germination rates of the three taxa. In the early seedling growth experiment, plant performance varied by taxa, and for the competition experiment there were no intra- or interspecific competition or treatment effects on the performance of plants. Overall, my research identified a potential mechanism allowing T. x glauca to dominate wetlands, and also shows that non-native lineages are being introduced into Canada through commercial trade Author Keywords: Competition, Germination, Non-native lineages, Plant nurseries, Seedling Growth, Typha spp.

Pages

Description

Graduate student theses produced at Trent University. You may also browse theses and dissertations by year, program, or author.

In collections

Search Our Digital Collections

Query

Enabled Filters

  • (-) ≠ Reid
  • (-) ≠ Morrison
  • (-) ≠ English (Public Texts)
  • (-) ≠ Materials Science

Filter Results

Date

1974 - 2024
(decades)
Specify date range: Show
Format: 2024/05/20

Collection

Author Name

Show more

Name (Any)

Show more

Degree

Degree Discipline

Show more

Subject (Topic)

Show more