Graduate Theses & Dissertations

Pages

An Analysis of Zoning By-laws and Urban Agriculture in the City of Peterborough, Ontario
Urban agriculture (UA) is becoming increasingly prevalent in Canadian cities. Despite this municipal zoning by-laws often do not address UA explicitly. Using eleven interviews of urban agricultural participants a case study of the City of Peterborough’s zoning by-laws and the barriers they might present to UA was conducted. Research suggests that UA can provide many benefits to urban areas. The analysis found that the City of Peterborough’s zoning by-laws do not directly address UA. In order to enable the development of UA in the City of Peterborough its zoning by-laws will need to be redesigned to address and regulate UA directly. Author Keywords: By-laws, food systems, land use, municipal planning, urban agriculture, zoning
Representations of Aboriginal Health in the Media
The goal of the present study was to explore the overall discourse within media articles regarding Aboriginal health issues. The present research aimed to answer the following questions: What Aboriginal health issues are being discussed in the media? How are Aboriginal health issues being discussed in the media? And, does the media propagate power imbalances between Aboriginal and non-Aboriginal Canadians? A thematic analysis was conducted, coopting aspects of Critical Discourse Analysis (CDA) to assess media content. Four CDA devices were used: overlexicalisation, structural oppositions, nominalizations and functional nominations, and concessions and hedging. Results suggest that while there are disparities in health outcomes between Aboriginal and non-Aboriginal Canadians, it is not widely reported in the media. The thematic analysis of 208 articles revealed patterns of stereotypical ideologies and negative framing appearing in media articles, the creation of an us versus them narrative, and themes of out of sight, out of mind, criminalizing Aboriginal Canadians, politicizing health, and access to health services. Author Keywords: Aboriginal Health, Communication, Health, Media, Psychology, Thematic Analysis
Practicing and Rewarding Task-Relevant Motor Variability to Optimize Motor Performance
It is universally accepted that human motor performance is variable in both its timing and spatial qualities. However, it is unclear to what extent motor variability impedes performance when learning a new skill and to what extent it enables our ability to learn. The first experiment examined whether performance during a test task depended on whether participants practiced to constrain or vary the task-relevant parameter. Participants used their right hand to make simple point-to-point movements. Results demonstrated the importance of paying attention to test task demands to evaluate which form of practice is most beneficial. The second experiment examined whether levels of variability could be manipulated using a reward-based paradigm to enhance learning when adapting to a perturbation of a simple visually-guided reaching movement. A reward-based feedback task was designed to encourage exploration along the task-relevant dimension, specifically movement direction variability. Overall, I did not find any significant results. Author Keywords: Adaptation, Motor Control, Motor Learning, Reaching
Robert Bringhurst and Polyphonic Poetry
Robert Bringhurst states that polyphonic art is a faithful, artistic reflection of the multiplicity of the world’s ecosystems. This ecocritical perspective recognizes that human art informs our understandings of the world, and therefore artists have a moral obligation towards that world. In Chapter One I argue that mimesis should be reclaimed as a useful literary category since all art, regardless of intentions, has an effect on both culture and the natural world. In Chapter Two I argue that by reconnecting publishing craft and philosophy, our books can serve to bring us more in tune with the structures of the natural world. I conclude in Chapter Three by asking how a counterpublic consciousness can be cultivated, and how Bringhurst’s mission of transforming culture might be fully realized. Altogether, this view of literature offers an antidote to Western culture’s destructive tendencies towards the natural world. Author Keywords: Bringhurst, ecocriticism, mimesis, poetry, polyphony, typography
Long-Term Population Dynamics of an Unexploited Lacustrine Brook Trout (Salvelinus fontinalis) Population
Long-term studies of demographic processes such as survival and abundance conducted in unexploited systems provide unique insight into the natural population ecology of fish, but are rarely available. I used historical tagging records of a sanctuary population of brook trout (Salvelinus fontinalis) in Algonquin Park, Ontario to investigate long-term population dynamics in an unexploited population. Adult brook trout in Mykiss Lake (23.5ha) were surveyed and tagged biannually (May and October) between 1990 and 2004. Open-population capture-mark-recapture models were used to test the importance of time, size, sex and season on estimates of apparent survival and abundance. Seasonal population growth and recruitment were estimated and compared with large-scale climate indices. Time-dependent survival and abundance estimates fluctuated, with distinct periods of increase. Population growth and recruitment were positively correlated with summer NAO and ENSO values, whereas survival was negatively correlated. Seasonally, larger individuals experienced higher apparent survival during winter and decreased survival during summer. These findings provide valuable insights into the natural demography of unexploited brook trout populations, and should help inform sustainable management of inland fisheries. Author Keywords: capture-mark-recapture, long-term, population dynamics, Salvelinus fontinalis, seasonal variation, survival
In situ measurements of trace metal species in the Athabasca and Mackenzie Rivers using diffusive gradient in thin films (DGT) devices
This study assesses the bioavailable metal (Cu, Ni, Zn, Pb) species in the Athabasca-Mackenzie watersheds using diffusive gradient in thin films (DGT) devices. Metal toxicity is not only based on the concentration of metal in natural waters, but also on the nature of metal species. Four main forms in aquatic systems are: free ion, inorganic species, DOM bound (humic) species and metal colloidal species. The free ion and inorganic species and very small humic species are known as DGT-labile species and, are considered to be more bioavailable to micro-organisms due to the size and thus may be toxic to microorganisms. In this study, DGT devices were applied to (1) monitor the DGT-labile metal species in the lower Athabasca River and the Mackenzie River watershed and (2) assess the DGT-labile metal concentrations on temporal and spatial scales. In the lower Athabasca River, comparison between the DGT results and the Windermere Humic Acid Model (WHAM) calculation indicated good agreements for all metals when the precipitated iron(III) hydroxide was assumed as an active binding surface. No significant variations in labile species were found over 2003-2012 (RAMP database) despite the development of oil sands. In the Mackenzie River, no significant difference in DGT-labile metal concentrations and DOC concentrations was found in yearly basis 2012-2014. Only DOC was lower in August (6.98 and 3.85 ppm, respectively; p< 0.05) due to dilution from heavy rain events. Spatially, DGT-labile Cu and Ni in the downstream Mackenzie River were higher than upstream (1.79 and 0.58 ppb for Cu, 1.68 and 0.77 ppb for Ni, 4.06 and 6.91 ppm for DOC; p < 0.05). Overall the in situ measurements of metals constitute a benchmark for future studies in water quality and be helpful in environmental management in Alberta and the Northwest Territories in Canada. Author Keywords: Athabasca River, DGT, Mackenzie River, Speciation, Trace Metal, WHAM
Bioremoval of copper and nickel on living and non-living Eugelna gracilis
This study assesses the ability of a unicellular protist, Euglena gracilis, to remove Cu and Ni from solution in mono- and bi-metallic systems. Living Euglena cells and non-living Euglena biomass were examined for their capacity to sorb metal ions. Adsorption isotherms were used in batch systems to describe the kinetic and equilibrium characteristics of metal removal. In living systems results indicate that the sorption reaction occurs quickly (<30 min) in both Cu (II) and Ni (II) mono-metallic systems and adsorption follows a pseudo-second order kinetics model for both metals. Sorption capacity and intensity was greater for Cu than Ni (p < 0.05) and were described by the Freundlich model. In bi-metallic systems sorption of both metals appears equivalent. In non-living systems sorption occurred quickly (10-30 min) and both Cu and Ni equilibrium uptake increased with a concurrent increase of initial metal concentrations. The pseudo-first-order model was applied to the kinetic data and the Langmuir and Freundlich models effectively described single-metal systems. The biosorption capacity of Cu (II) and) was 3x times greater than that of Ni (II). Sorption of one metal in the presence of relatively high concentrations of the other metal was supressed. Generally, it was found that living Euglena remove Cu and Ni more efficiently than non-living Euglena biomass in both mono- and bi-metallic systems. It is anticipated that this work should contribute to the identification of baseline uptake parameters and capacities for Cu and Ni by Euglena as well as to the increasing amount of research investigating sustainable bioremediation. Author Keywords: accumulation, biosorption, Cu, Euglena gracilis, kinetics, Ni
On (Digital) Photographic Image-Objects
On the first page of the much read, Camera Lucida, Roland Barthes reveals his motive: “I was overcome by an “ontological” desire: I wanted to learn at all costs what Photography was “in itself,” by what essential feature it was to be distinguished from the community of images.” The impetus of this thesis might be called a Barthesian desire to learn what distinguishes digital photographic images from all other photographic images. Throughout, I ask: what is a digital image? The first exploratory turn reflects upon photographs and touch. While photographs are objects that are both touched and touching, digital images are inscrutable data assemblages that resist touch and are predisposed to speed. Digital images cannot be touched, yet are responsive to touch. Through the mediating magic of touch sensitive glass, we command digital images to move. Chapter two considers prevailing late twentieth century theory on the digital photograph that claims the eclipse of film by digital imaging will render [digital] photographs totally unreliable documents. The results have been surprising; although suspicion about digital image bodies has crept into the cultural psychological fabric, I argue that we still believe in the basic veracity of [digital] photographic images. Finally, I turn my attention to the objecthood of digital imageobjects in a discussion of the widely unacknowledged materiality of data. Digital image-objects—those speedy, untouchable, dubious, things—are heavy. The weight of their bodies moving in the vast—unseen—global technological infrastructure is the burden of my final reflection. Author Keywords: death of film, digital materiality, digital photographic realism, ontology of the image, philosophy of photography, photography after photography
Understanding the Role of Lived Experience in Community Leaders’ Vision and Governance of Economic Development and Sustainability in Rurally Situated Small Cities
Sustainable development is normative - making decisions in the present that construct the experience of place for the future. It is primarily driven by global measures developed to meet the needs of the present while ensuring future generations can meet their own needs. These measures attempt to balance economic prosperity, social justice, and environmental stewardship in many nations. This attempt to balance a plurality of outcomes creates socio-political tensions in choosing between alternatives. These barriers and tensions are characterized through the neoclassical vision of: economics as a science, utility maximization, and alienation of people. This thesis explores the lived experience of community leaders in Peterborough, Ontario as they navigate a contentious and current debate of where to relocate a casino in the region. The results focus on the tension experienced by community leaders as they seek to balance elements of care, while preserving neoclassical values of growth, individualism, freedom of choice, and interconnectedness. The thesis concludes with a model that works towards an understanding of the role of lived experience in economic development decision-making in rurally situated small cities, and recommendations for further research and policy recommendations. Author Keywords: economic development, governance, lived experience, small city, sustainable development, vision
Relationships between Dissolved Organic Matter and Vanadium Speciation in the Churchill River, MB and the Mackenzie River Basin, NWT using diffusive gradients in thin films (DGT)
This study examines the influence of dissolved organic matter (DOM) on dissolved vanadium (V) speciation in the Churchill River and Great Slave Lake using diffusive gradients in thin film (DGT). Vanadium is commonly found in natural environments such as rivers, lakes and oceans. It regulates normal cell growth, but in excessive amounts, it can have toxic effects on human and aquatic organisms. The use of in situ, time integrated DGT devices allows to better (1) monitor the most bioavailable fraction of V, the DGT-labile V, in Arctic Rivers and (2) assess the influence of DOM on dissolved V speciation. Higher DGT-labile V was found in the the central regions of the Mackenzie River (MR), with an average of 7.7 ± 2.3 nM, likely due to sediment leaching and permafrost thawing. The Churchill River and Great Slave Lake (GSL) showed lower DGT-labile V levels (2.2 ± 1.6 nM and 3.6 ± 2.7 nM, respectively), compared to central regions in MR. The CR DGT-labile V concentrations was positively correlated to protein-like DOM concentration and abundance (r = 0.3, p < 0.05). The data collected from this study will help in developing new strategies regarding environmental health and impact assessments of environmentally hazardous waste that consist of potentially high levels of toxic vanadium species. Developments in the use of DGT devices as a sampling method will also aid in future studies involved in analyzing environmental health and specifically dissolved V species in natural waters. Author Keywords: diffusive gradients in thin-films, dissolved organic matter, fluorescence, mass spectrometry, UV-Vis, vanadium
Lipid-derived Thermoplastic Poly(ester urethane)s
Thermoplastic poly(ester urethane)s (TPEU)s derived from vegetable oils possess inferior physical properties compared to their entirely petroleum-based counterparts due to the structural limitations and lower reactivity of the precursor lipid-derived monomers. The present work shows that high molecular weight of TPEUs with enhanced performance can be obtained from lipid-derived monomers via (i) the synthesis of polyester diols with controlled molecular weights, (ii) the tuning of the functional group stoichiometry of the polyester diols and the diisocyanate during polymerization, (iii) the degree of polymerization (iv) the control of the hard segment hydrogen bond density and distribution via the use of a chain extender and (v) different polymerization protocols. Solvent-resistant TPEUs with high molecular weight displaying polyethylene-like behavior and controlled polyester and urethane segment phase separation were obtained. Structure-property investigations revealed that the thermal transition temperatures and tensile properties increased and eventually plateaued with increasing molecular weight. Novel segmented TPEUs possessed high phase separation and showed elastomeric properties such as low modulus and high elongation analogous to rubber. The response of the structurally optimized TPEUs to environmental degradation was also established by subjecting the TPEUs to hydrothermal ageing. TPEUs exhibited thermal and mechanical properties that were comparable to commercially available entirely petroleum-based counterparts, and that could be tuned in order to achieve enhanced physical properties and controlled degradability. Author Keywords: Hydrothermal degradation, Molecular weight control, Polyester diols, Renewable resources, Structure-property relationships, Thermoplastic poly(ester urethane)s
Conservation genetics of Redside Dace (Clinostomus elongatus)
Recent range reductions of endangered species have been linked to urban development, increased agricultural activities, and introduction of non-native species. I used Redside Dace (Clinostomus elongatus) as a focal species to examine the utility of novel monitoring approaches, and to understand historical and contemporary processes that have influenced their present distribution. I tested the efficacy of environmental DNA (eDNA) to detect Redside Dace, and showed that eDNA was more sensitive for detecting species presence than traditional electrofishing. Parameters such as season, number of replicates, and spatial versus temporal sampling need to be accounted for when designing an eDNA monitoring program, as they influence detection effectiveness and power. I also assessed the species’ phylogeographic structure using both mitochondrial and microsatellite DNA analysis. The data from the microsatellite markers indicate that Redside Dace populations are genetically structured, with the exception of several populations from the Allegheny River basin. Combined sequence data from three mitochondrial genes (cytochrome b, ATPase 6 and ATPase 8) indicated that Redside Dace persisted within three Mississippian refugia during the last glaciation. Secondary contact between two lineages was indicated by both mitochondrial and microsatellite data. The combined results from the eDNA and conservation genetics studies can be used to inform Redside Dace recovery efforts, and provide a template for similar efforts for other aquatic endangered species. Author Keywords: eDNA, endangered, genetics, phylogeography

Pages

Search Our Digital Collections

Query

Filter Results

Date

1974 - 2024
(decades)
Specify date range: Show
Format: 2024/03/28