Graduate Theses & Dissertations

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Perspectives on Poultry
The contemporary denigration of poultry combined with the intensification of industrialized animal agriculture has deepened divides between humans and poultry, creating a disconnect that holds implications for both parties and the sustainability of North American food systems. This study explores how people with poultry keeping experience perceive these animals, how their views are influenced and how these narratives may intersect with themes of sustainability. Surveys and interviews aimed at small flock keepers and commercial farmers within an area of Central Ontario revealed that poultry sentience was widely recognized among participants. Overall, this study’s findings disrupt commonly held notions that poultry are one-dimensional beings and highlight the mutual benefits that can come when the distance is lessened between humans and poultry. This research contends that reimagining human-poultry relationships could improve our ability to consider and challenge dominant systems that perpetuates unsustainable food production and negatively affects both animal and human life. Author Keywords: history poultry keeping, human-animal studies, human-poultry relationships, keeper attitudes, poultry sentience, sustainable food systems
Extraction and Characterization of Hyaluronic Acid and Collagen from Eggshell Membrane Waste
Connecting academia to industry is one important way to advance towards meeting the United Nations (UN) Sustainability Goals (SDGs).1 Sustainability can be applied to all industrial sectors with the SDGs being implemented by 2030.2 This research contributes to the SDGs by investigating a way to remediate an industrial waste stream in the egg-breaking industry. If adopted, this would reduce the amount of eggshell membrane (ESM) waste placed in landfill where it does not decompose properly. The work described in this thesis specifically targets extraction of collagen and hyaluronic acid (HA), two components of the ESM that are of commercial value in the cosmetic, pharmaceutical, and biomedical industries3,4 . Deliverables from this research include economically viable extraction methods, developed based on green chemistry approaches, that can be transferred from lab bench to industrial scale. The extraction development process was guided by the 12 Principles of Green Chemistry5,6,7 and the 12 Principles of Green Engineering.8 HA was most successfully extracted using a sodium acetate solution on ground ESM. Filtrate was collected, exhaustively dialyzed and lyophilized. High molecular weight HA was recovered. Fourier transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy and proton nuclear magnetic resonance (NMR) spectroscopy compared extracted material to reference HA identifying successful extraction. Collagen was extracted using acetic acid or pepsin enzyme digestion. Hydrophilic interaction liquid chromatography (HILIC) coupled with mass spectrometry (MS) compared amino acid composition of extracted materials to reference collagen material. FTIR-ATR spectra also supported successful extraction of collagen. This work identifies that HA and collagen can be conveniently extracted from ESM using an economical approach that can be implemented into egg-breaking facilities. This work highlights the benefits of connecting academia to industry to advance green chemical approaches while implementing sustainable practices into existing industry. Author Keywords: collagen, eggshell membrane waste, extraction, green chemistry, hyaluronic acid, sustainability
Finding Cowboy Joe
Canadian authored diverse LGBTQ2S children's picture books can help counter socialized aspects of heteronormativity and other forms of oppression. This thesis outlines the challenging process for identifying and locating Canadian authored diverse LGBTQ2S children's picture books, with suggestions provided for mitigating this process. Twenty-two books (list and summaries included) are collected and then analysed through three different lenses: Sipe’s Semiotically Framed Theory of Text-pictured Relationships; intersectionality; and Canadian Studies. Findings include: the significance of a micro press in offering representation for queer intersectionality, the shift from the portrayal of discrimination against queer parents to an attention to the policing of children’s gender identity and expression, and the embrace of the child on their own terms. In addition, a Canadian queer children’s book has been created by the researcher, developed through the process of writing of this thesis. Author Keywords: Canadian authors, Canadian identity, children’s picture books, countering heteronormativity, ethnic diversity, LGBTQ2S
(Re)encountering black bears
This thesis explores the perceptions of human-bear interactions in Ontario, suggesting that they have been shaped by narratives that have roots in colonial perceptions of nonhuman animals. Further, I seek to consider how these interactions could unfold differently if we rethought our relationships and responsibilities to these beings, in particular through an embrace of Indigenous-led conservation informed by ideas of animal welfare. The methods used for this research were first empirical, through qualitative data collection via interviews. Second, it was interpretive, through the observation of bear experiences and through the analysis of circulated and conceptual themes of bear information found in media articles. What emerged was an understanding that the mitigation efforts which are used when human-bear interactions occur are deeply influenced by political, social, and cultural factors that cannot be removed from these matters, asserting that a reconceptualization of current conservation frameworks needs to be considered. Author Keywords: Compassionate conservation, Human-bear interactions, Human-wildlife relations, Indigenous conservation, Narrative inquiry, Wildlife conservation
Adoption of a Finite Element Model of Material Deformation Relevant to Studying Corneal Biomechanics
The human cornea is required to exhibit specific material properties to maintain its regular shape under typical intraocular pressures which then allow for its correct optical functionality. In this thesis, the basis of continuum solid mechanics and the finite element method are introduced. We use finite element modelling to simulate the extension of an effective-1d, linear-elastic bar, a cornea-like body governed by Poisson’s equation, and the deformation of a loaded, linear-elastic, cube. Preliminary results for the deformation of a simulated, linear-elastic, cornea have also been achieved using the finite element approach. Author Keywords: continuum solid mechanics, corneal biomechanics, finite element method, intraocular pressure
Through the eyes of the Ontario farmer
Dairy goat farming has become increasingly popular in recent years in Ontario. This qualitative study done by semi-structured interviews, examines the why and the wherefore of the opinions held by dairy goat farmers in Ontario in regards to sustainable agriculture. It was found that these farmers feel that sustainable agriculture is important. These farmers believed their farms to be sustainable and have implemented sustainable farming practices that reflect these interests. Their primary interest is to maintain their farmland for the use of future generations as well as maintaining the economic and environmental sustainability of their farms. There is currently a lack of scientific information available for dairy goat farmers in Ontario. Challenges presented by the participants should be researched so as to better serve this budding industry which may become one of the most sustainable livestock industries in Ontario. Author Keywords: agriculture, dairy goat, farmer opinion, farming, sustainability, sustainable agriculture
Modelling Depressive Symptoms in Emerging Adulthood
Depression during the transition into adulthood is a growing mental health concern, with overwhelming evidence linking the developmental risk for depressive symptoms with maternal depression. In addition, there is a lack of research on the protective role of socioemotional competencies in this context. This study examines independent and joint effects of maternal depression and trait emotional intelligence (TEI) on the longitudinal trajectory of depressive symptoms during emerging adulthood. A series of latent growth models was applied to three biennial cycles of data from a nationally representative sample (N=933) from the Canadian National Longitudinal Survey of Children and Youth. We assessed the trajectory of self-reported depressive symptoms from age 20 to 24 years, as well as whether it was moderated by maternal depression at age 10 to 11 and TEI at age 20, separately by gender. The results indicated that mean levels of depression declined during the emerging adulthood in females, but remained relatively stable in males. Maternal depressive symptoms significantly positively predicted depressive symptoms across the entire emerging adulthood in females, but only at age 20-21 for males. In addition, likelihood of developing depressive symptoms was attenuated by higher global TEI in both females and males, and additionally by higher interpersonal skills in males. Our findings suggest that interventions for depressive symptoms in emerging adulthood should consider development of socioemotional competencies. Author Keywords: Depression, Depressive Symptoms, Emerging Adulthood, Intergenerational Risk, Longitudinal, Trait Emotional Intelligence
Radiocarbon Analysis of the Middle to Late Woodland Transition in Southern Ontario
The goal of the thesis is to establish the temporal patterning of the cultural complexes of the Middle to Late Woodland periods in Ontario. To do so I examine the statistical shape and phase boundaries of samples of radiocarbon dates associated with the Princess Point, Sandbanks, Glen Meyer, and Pickering archaeological complexes. The radiocarbon dates used for this thesis were collected through published sources, grey literature, and resources such as the Canadian Archaeological Radiocarbon Database. Each date was put through a data hygiene process and those deemed acceptable were merged into Summed Probability Distributions (SPDs) and further analysed through the r-carbon and OxCal packages. Bayesian statistics were used to estimate the start and end dates per complex, Shapiro-Wilks tests were used to examine the legitimacy of cultural entities, and the amount of geographic, and chronological overlap was determined by randomly sampling between the compared datasets to determine an acceptable threshold of randomness. Results indicate that the Princess Point complex does not meet the requirements of a culturally homogeneous archaeological cultural group. There is no difference in the Glen Meyer and Pickering radiocarbon patterns, which supports combining them into a single cultural designation. It was impossible to evaluate the Sandbanks complex due to a lack of radiocarbon data, although overall it seems to agree with the current understanding of the complex. Author Keywords: Glen Meyer, Ontario Archaeology, Pickering, Princess Point, Radiocarbon, Sandbanks
Paper Chase
"The Paper Chase: A Survey of Student Newspapers on Ontario Campuses in the 1960s" is a regional study of three University campuses in Ontario — the University of Toronto, Queen's University and Trent University — and examines each of these institutions’ respective student newspapers, The Varsity, The Queen's Journal, and The Arthur as a primary source analysis. In broader terms, this thesis looks to theoretically historicize the themes of "life," "love," and "liberty" on Ontario campuses in the 1960s. Its central question is whether Ontario's youth experienced a cultural revolution like that portrayed in popular memory of the period, which profoundly appears in other sixties cultural interpretations in Canada and the United States. By framing student life through student newspapers' gamut, this thesis calls into question the lionization of some cultural decade elements. It determines students were, in fact, in some ways much more conservative in their outlook than earlier literature or the popular memory of the period suggests. History has much to say about students who rebelled. This thesis focuses on those who did not. Author Keywords: Conservatism, Counterculture, Queen’s University, Sixties, Trent University, University of Toronto
Postclassic Maya Diet
Postclassic (AD 900-1500) Maya diet at Ka’kabish, Belize was examined using stable carbon and nitrogen isotope analysis of human bone collagen, and stable carbon isotope analysis of bone structural carbonate. Isotope data were compared to skeletal and dental indicators of diet and disease, and dietary differences among burials excavated from chultuns (B-2, C-1, C-2, and C-3) at Ka’kabish. Varying in dimensions, chultuns are characterized as multiple subterranean chambers carved into limestone bedrock, where re-entry was permitted through the removal of a capstone placed over a circular entrance. Due to poor preservation and commingling of human remains, diet and its relation to age, sex, and social status could not be explored. The general diet at Ka’kabish is consistent with the consumption of a diverse range of terrestrial plants and animals, in addition to marine resources. Relative to the other chultun burials, Chultun C-2 is an outlier, with a noticeably different diet, evidence for skeletal pathology, and absence of dental modifications. This study demonstrates a lack of significant dietary differences among Postclassic Maya sites in northern Belize, along with an apparent reliance on marine resources, further supporting the notion of a close association, and equal participation in a regional trading system with coastal sites that allowed for populations in this region to thrive during the Postclassic period. Author Keywords: Ancient Maya, Bioarchaeology, Ka'kabish, Osteology, Postclassic, Stable Isotopes
Chew the Fat
Fatty acid analysis was performed on archaeological bone from various fauna from sites in the Canadian arctic to better understand the preservation of fatty acids and their potential applications to palaeoecological and palaeodietary studies. These data were complemented by analyses of modern bone and soft tissue samples from livestock and harp seals (Pagophilus groenlandicus). Results of modern analyses revealed that in terrestrial species, bone has inherently lower concentrations of most fatty acids relative to other soft tissues (adipose, marrow, and muscle). These analyses suggest that the distribution of fatty acids in bone is unique compared to other tissues, and the types and abundances of fatty acids in bone may be linked to dietary sources of lipids. Of the archaeological samples analyzed, terrestrial species (caribou [Rangifer tarandus]) generally exhibited higher concentrations of saturated fatty acids compared to marine species (ringed seals [Pusa hispida] and polar bears [Ursus maritimus]), whereas marine species had higher concentrations of monounsaturated fatty acids compared to terrestrial species. Results of analyses on both modern and archaeological samples provided insight into the degradation of fatty acids in bone, and the rapid loss of polyunsaturated fatty acids in particular. Because the abundances of fatty acids are likely altered in the burial environment, it is recommended that future analyses incorporate compound specific isotope analysis to focus on applications of fatty acids that are typically in the highest abundance and arguably have undergone the least amount of change, including palmitic (C16:0) and stearic acid (C18:0) Author Keywords: Archaeological Science, Bone Lipids, Fatty Acid Analysis, GC-MS, Lipid Preservation, Palaeoecology
UV-Curable hybrid sol-gel materials
This thesis describes the synthesis, application and evaluation of a UV crosslinked 3-methacryloxypropyltrimethoxysilane-derived coating formulation. This is a two-component sol-gel system with 3-methacryloxypropyltrimethoxysilane (MaPTMS) and tetraethoxysilane (TEOS). Herein we show that if we change the co-solvent required for solubilizing MaPTMS from the more common methanol and ethanol to isopropanol we change the rate of hydrolysis from days or weeks to minutes. With the assistance of 2D 29Si-NMR we demonstrate that the system undergoes extensive condensation in twenty minutes. Using standard UV irradiation, the material can be extensively UV crosslinked with 70% of the methacryloxy functionality being consumed in 5 minutes upon irradiation in the presence of a photo-initiator. When this material is used to coat low carbon steel and immersed in an accelerated corrosion solution (dilute Harrison’s solution); this material affords low carbon steel 25 hours of protection when crosslinked and 17 hours of protection when uncrosslinked. The material was then used to encapsulate polyaniline (PANI), an intrinsic conductive polymer used in the corrosion protection of metal substrates. PANI has been encapsulated previously in sol-gel material, but due to the pH dependence of the solubility of PANI, it can not be encapsulated in more commonly chemically crosslinked sol-gel. As our system is UV crosslinked rather than chemically crosslinked, we were able to successfully demonstrate the inclusion of PANI into our coating system. Finally, this thesis includes a thorough computational investigation into the structure and band gap of PANI. Through the analysis of the band gap it was shown that the structure of the polymer commonly displayed in literature is not the correct structure of the polymer. Our results suggest that when PANI is made electrochemically, the oligomer contains two quinoid units next to one another instead of the more usually represented regularly alternating benzoid and quinoid units. The results also suggest that when PANI is made using the oxidant ammonium persulfate, the polymer most likely contains a Michael adduct structure somewhere in the polymer chain which dominates PANI’s electronic properties. Author Keywords: 3-Methacryloxypropyltrimethoxysilane, Computational Chemistry , Corrosion , Polyaniline, Tetraethoxysilane

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Format: 2023/02/02