Graduate Theses & Dissertations

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Evaluating the Effects of Habitat Loss and Fragmentation on Canada Lynx
Current major issues in conservation biology include habitat loss, fragmentation and population over-exploitation. Animals can respond to landscape change through behavioural flexibility, allowing individuals to persist in disturbed landscapes. Individual behaviour has only recently been explicitly included in population models. Carnivores may be sensitive to changing landscapes due to their wide-ranging behaviour, low densities and reproductive rates. Canada lynx (Lynx canadensis) is a primary predator of snowshoe hares (Lepus americanus). Both species range throughout the boreal forests of North America, however lynx are declining in the southern range periphery. In this dissertation, I developed new insights into the effects of habitat loss and fragmentation on lynx. In Chapter 2, I created a habitat suitability model for lynx in Ontario and examined occurrence patterns across 2 regions to determine if habitat selection is flexible when different amounts of habitat are available. Although lynx avoided areas with <30% suitable habitat where suitable land cover is abundant, I found that they have flexible habitat selection patterns where suitable land cover is rare and occurred in low habitat areas. In Chapter 3, I investigated the effects of dispersal plasticity on occupancy patterns using a spatially explicit individual-based model. I showed that flexible dispersers, capable of crossing inhospitable matrix, had higher densities and a lower risk of patch extinction. In contrast, inflexible dispersers (unable to cross inhospitable matrix), were most limited by landscape connectivity, resulting in a high extinction risk in isolated patches. I developed three predictions to be explored with empirical data; (1) dispersal plasticity affects estimates of functional connectivity; (2) variation in dispersal behaviour increases the resilience of patchy populations; and (3) dispersal behaviour promotes non-random distribution of phenotypes. Finally, in Chapter 4, I examined the consequences of anthropogenic harvest on naturally cycling populations. I found that harvest mortality can exacerbate the effects of habitat fragmentation, especially when lynx densities are low. Dynamic harvest regimes maintained lynx densities and cycle dynamics while reducing the risk of population extinction. These results suggest that lynx display some flexibility to changing landscapes and that the metapopulation structure is more resilient to increasing habitat loss and fragmentation than previously understood. Future studies should focus on determining a threshold of connectivity necessary for population persistence and examining the effects of habitat loss on the fecundity of lynx. Author Keywords: Fluctuating Populations, Habitat Fragmentation, Landscape Ecology, Occupancy Dynamics, Population Ecology, Spatially Explicit Population Models
Return to "The Child"
Despite - or perhaps because of - her popularity as a best-selling poet, the work of Mary Oliver has been minimized and marginalized within the academy. Nevertheless, Oliver's readership is an expansive and devout one made up of a wired yet insular North American public in search of reconnecting with the natural world. I propose that through Oliver's poetry readers access the affective, sensory responses to nature first encountered during childhood. This return to "the child" is deliberately used by various publics to share communal goals. Drawing from such frameworks as ecocritical and trauma theory, I explore environmental memory, ecstatic places, and the sensuousness of nature and language to consider ways in which diverse publics claim and use Oliver's work. I provide a close reading of selections of Oliver's poems to argue that her work's appeal speaks to a revived perception of the necessity of nature to the human spirit Author Keywords: Attentiveness, Childhood, Language, Mary Oliver, Nature Poetry, Senses
Role of Multiple Nights of Sleep in the Consolidation of an Engaging and Complex Motor Learning Task
The present study examined the role of multiple nights of sleep in the consolidation of a complex motor learning task. Participants were 24 Trent undergraduates, 12 in the learning group (Mage = 20.33, SD = 1.87, 10 female) and 12 in the control group (Mage = 21.92, SD = 3.42, 7 female). Participants underwent 5 consecutive nights of polysomnographic recordings, with a Rock Band learning session on the third night. A series of 2(group)x4(night) ANOVAs were performed on the sleep variables. Interactions were found in the number of spindles detected at Pz, F(333) = 9.19, p <.01, and in the density of spindles detected at Pz, F(3,33) = 4.06, p <.05. The pattern of changes from baseline was significantly different between the two groups; spindles increased in the learning group and decreased in the control group. The novel finding was that spindle number/density remained elevated at the third post-learning night of sleep. Author Keywords: Motor Learning, Procedural Memory, Sleep, Sleep Spindles
BACKGROUND PRACTICES, AFFORDANCES, AND THE FRAME PROBLEM
This project is a Heideggerian critique of the subject/object metaphysic presupposed in the Representationalist claim that the world is made intelligible solely in virtue of internal states that bear representations. It is comprised of two sections. The first is a critique of the ontological primacy of representational-intentionality/action in which I argue that where Brentano, Husserl, and Searle have erred is not in their model of intentionality/action, but in assigning a priori status to a derivative mode of being. The second is a critique of representation-driven artificial intelligence whereby I argue that belief-fixation and action selection that is context-dependent produces an insurmountable problem that prevents the parsing of context-specifying relevance; the corollary being that the world is not disclosed despite that system having a structurally isomorphic internal constitution to that which is purported by the Representationalist to obtain in human beings. With the issue thus framed, I conclude by arguing that this problem is dissolved within a Heideggerian phenomenological framework. Author Keywords: Artificial Intelligence, Heidegger, Phenomenology, Representationalism, Skillful Coping, The Frame Problem
Not In Their Classrooms
This dissertation examines the rise of teachers' union militancy in Ontario through a case study of the Federation of Women Teachers' Associations of Ontario (FWTAO) and the Ontario Public School Teachers' Federation (OPSTF) between 1970 and their amalgamation into the Elementary Teachers' Federation of Ontario (ETFO) in 1998. It uses the archival records of the two unions, relevant legislation, media records, personal collections, and interviews to explore how these two professional organizations became politicized, militant labour unions able to engage with the state and the trustees of boards of education. The Introduction situates the public education project within nation building in a capitalist-democracy and outlines the theoretical influences informing the dissertation. Chapter 1 follows the two unions during the 1970s as they developed into labour unions. The 18 December 1973 one-day, province-wide, political strike achieved the right to strike and established a unique labour regime for teachers. Chapter 2 examines the advance of the unions during the 1980s as they developed labour militancy. At the same time, neo-liberalism was ascending and the post-war social accord was coming to an end resulting in attacks on unions and cuts to social programs. How gender affected the elementary teachers' unions between 1970 and 1990 is developed in Chapter 3. The FWTAO campaigned for women's equality on a platform of liberal feminism while the OPSTF followed a unionist path in an effort to convince women teachers to join them. Chapter 4 scrutinizes the effect of neo-liberal ideology on education during the 1990-1995 Bob Rae NDP government and the impact the Social Contract had on teachers. The development of teacher resistance to the neo-liberal state is explored in Chapter 5. Alliances with other labour organizations during the Days of Action campaign culminated in a two-week, province-wide strike in the fall of 1997 against the Mike Harris Conservative government. The Conclusion brings together the findings of the dissertation and suggests future research exploring teacher union strength in the Canadian context. Author Keywords: Federation of Women Teachers' Associations of Ontario; FWTAO, neoliberalism, Ontario Public School Teachers' Federation; OPSTF, teachers' strikes, teachers' unions, women's union
(un)Natural Provocation
My thesis examines anthropomorphism and many avenues in which humans represent nonhumans to evaluate their own lives. Using Isabella Rossellini's Green Porno webseries, a collection of two-minute films starring Rossellini as a multitude of nonhumans with costumes transforming her into nonhuman, I posit that a new form of anthropomorphism -- one that values the nonhuman in all his or her nonhumanity -- is emerging in contemporary media. Rossellini describes the mating, seduction, and maternal instincts of these nonhumans, regularly drawing parallels between nonhuman and human behavior and uncovering crucial intersections in femininity, masculinity, queer theory, and abjection. In more recent films, I see Rossellini performing certain nonhumans to critique particular characteristics of Western human society and incredulously addressing the human viewer as a member of a species that might not be as high in the caste system of living beings as he or she is led to believe. In turning this sense of grotesque Otherness onto the human, I identify Rossellini as engaging in counterabjection, or the reversal of extreme degradation often projected upon nonhuman bodies by humans. Author Keywords: abjection, animal studies, nonhuman, queer studies
American Acropolis, American Ruins
Since 1979, photographer and sociologist Camilo José Vergara has taken repeat photographs of American cities in decline, focusing on evolving landscapes of postindustrial decay. Vergara's images subscribe to an aesthetic of ruin while providing a record of America's crumbling ghettos rooted in social documentary concerns. Vergara's work diverges from the ahistorical tendencies of contemporary ruin porn photography: by challenging the photograph's temporal stasis Vergara bears witness to the ongoing reality of disenfranchisement, assembling an archive that takes up the Benjaminian task of doing history in images. Vergara's photographs challenge standard photojournalistic portrayals of violence, particularly the ways in which `violent' African American and Hispanic inner city populations have been erroneously cast as the cause of their own economic misfortune. The Invincible Cities website assists Vergara in drawing attention to forgotten places but also complicates his mandate to engage outside viewers by distancing them from the real-­world environments his photographs portray. Author Keywords: Camilo José Vergara, imagistic history, postindustrial decline, repeat photography, ruin porn, Walter Benjamin
Carbon and Nitrogen Isotope Changes in Streams along an Agricultural Gradient
Nitrogen is a major constituent of agricultural fertilizers, and nitrogen inputs to stream water via runoff and groundwater lead to a variety of negative environmental impacts. In order to quantify the movement of nitrogen through aquatic food webs, fourteen streams with varying land uses across South-Central Ontario were sampled for two species of fish, freshwater mussels, and water for measurement of isotope ratios of δ15N and δ13C. I found that nitrogen isotopes in fish, water, and mussels were related to the percentage of riparian monoculture, and that carbon isotopes were unrelated to monoculture. Though all species were enriched as monoculture increased, the rate of δ15N enrichment as monoculture increased did not vary between species. This study has improved our understanding of how monoculture affects nutrient enrichment in stream food webs, and assesses the validity of using nitrogen isotopes to measure trophic positions of aquatic organisms across an environmental gradient. Author Keywords: agriculture, fish, food webs, nitrogen, stable isotopes, streams
Scientificity of Psychology and the Categorical Paradigm of Mental Illness
There is little research devoted to exploring psychology's historical and discursive development. Psychological knowledge is generally presented as the contributions of individuals, but without context. The social, political, and economic aspects of psychology's development are scarcely discussed, including how the discipline came to be considered a science. This thesis project explored the history of the development of psychology. Specifically, psychology's claim to scientificity via the appropriation of the medical model of disease, and accordingly, the instantiation of the categorical paradigm of mental illness were examined. The discontinuous events that shaped psychology and its hallmark of scientificity were explored, including extensive concept transformations, political agendas, and marketing strategies. These practices were then explored in a practical way using the conception of clinical depression and the role of antidepressants as the first-line treatment for depression in the USA. This exploration revealed psychology's socio-historical contingencies and its agenda of prediction and control. Author Keywords: Categorical Paradigm, Concept Transformations, Historicity, Knowledge Products, Psychology, Scientificity
Seasonal variation in nutrient and particulate inputs and outputs at an urban stormwater pond in Peterborough, Ontario
Stormwater ponds (SWPs) are a common feature in new urban developments where they are designed to minimize runoff peaks from impervious surfaces and retain particulate matter. As a consequence, SWPs can be efficient at retaining particle-bound nutrients, but may be less efficient at retaining nutrients that are present primarily in the dissolved form, like nitrogen (N). However, the forms of nutrients (e.g. particulate vs. dissolved) likely differ with hydrologic and seasonal conditions and few studies have examined year-round differences in nutrient forms and concentrations at urban SWPs. In order to contrast total suspended solids (TSS), phosphorus (P) and nitrogen (N) levels between low and high flow conditions, sampling was conducted at an urban SWP in Peterborough, ON between November 2012 and October 2013. Only an increase in TSS levels at the outflow between low and high flow conditions was observed, as well as a decrease in TSS levels at the outflow compared to Inflow 1 under low flow conditions. Nitrate-N (NO3-N) was the dominant form of N entering the pond under all flow conditions, whereas the fraction of total-P (TP) that was particulate increased under high flow conditions. Nevertheless, the dissolved fraction of TP was consistently high in these urban inlets. Only NO3-N was significantly greater in the inflows than outflow and only under low flow conditions. Increases in the proportions of organic-N and ammonium-N in the outlet suggest that biological processing is important for N retention. Author Keywords: nitrogen, Ontario, phosphorus, stormwater ponds, total suspended solids
"Learning to Be Mad, In a Dream"
The Beat Generation shaped, and was shaped by, the post-WWII containment culture that arose in 1950s America. This so-called cultural containment reflected the social, political, and economic factors that were unique to the post-WWII period and are often considered concurrent to post-war McCarthyism, which promoted a national ideology of exclusionism that was foremost opposed to the threat of Communism. I propose in my thesis that containment was a major influence in the rhetoric of resistance that is found within the most prominent works of the Generation. My thesis also looks at the how Beat literature shifted from the counterculture to the mainstream and the impact that celebrity had on the Generation. When the Beats achieved literary fame their counterculture represented the forefront of the New Left and was synonymous with succeeding protest cultures of the 1960s. Author Keywords: Beat Generation, Cold War, Containment Culture, McCarthyism, Postmodernism, Second Wave Feminism
Fate of Silver Nanoparticles in Lake Mesocosms
The fate of silver nanoparticles (AgNPs) in surface waters determines the ecological risk of this emerging contaminant. In this research, the fate of AgNPs in lake mesocosms was studied using both a continuous (i.e. drip) and one-time (i.e. plug) dosing regime. AgNPs were persistent in the tested lake environment as there was accumulation in the water column over time in drip mesocosms and slow dissipation from the water column (half life of 20 days) in plug mesocosms. In drip mesocosms, AgNPs were found to accumulate in the water column, periphtyon, and sediment according to loading rate; and, AgNP coating (PVP vs. CT) had no effect on agglomeration and dissolution based on filtration analysis. In plug mesocosms, cloud point extraction (CPE), single-particle-inductively coupled mass spectroscopy (spICP-MS), and asymmetrical flow field-flow fractionation (AF4-ICP-MS) confirmed the temporal dissolution of AgNPs into Ag+ over time; however, complexation is expected to reduce the toxicity of Ag+ in natural waters. Author Keywords: AF4-ICP-MS, cloud point extraction, fate, mesocosms, silver nanoparticles, SP-ICP-MS

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1973 - 2033
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Format: 2023/10/03