Graduate Theses & Dissertations


Mitigating Cold Flow Problems of Biodiesel
The present thesis explores the cold flow properties of biodiesel and the effect of vegetable oil derived compounds on the crystallization path as well as the mechanisms at play at different stages and length scales. Model systems including triacylglycerol (TAG) oils and their derivatives, and a polymer were tested with biodiesel. The goal was to acquire the fundamental knowledge that would help design cold flow improver (CFI) additives that would address effectively and simultaneously the flow problems of biodiesel, particularly the cloud point (CP) and pour point (PP). The compounds were revealed to be fundamentally vegetable oil crystallization modifiers (VOCM) and the polymer was confirmed to be a pour point depressant (PPD). The results obtained with the VOCMs indicate that two cis-unsaturated moieties combined with a trans-/saturated fatty acid is a critical structural architecture for depressing the crystallization onset by a mechanism wherein while the straight chain promotes a first packing with the linear saturated FAMEs, the kinked moieties prevent further crystallization. The study of model binary systems made of a VOCM and a saturated FAME with DSC, XRD and PLM provided a complete phase diagram including the thermal transformation lines, crystal structure and microstructure that impact the phase composition along the different crystallization stages, and elicited the competing effects of molecular mass, chain length mismatch and isomerism. The liquid-solid boundary is discussed in light of a simple thermodynamic model based on the Hildebrand equation and pair interactions. In order to test for synergies, the PP and CP of a biodiesel (Soy1500) supplemented with several VOCM and PLMA binary cocktails were measured using a specially designed method inspired by ASTM standards. The results were impressive, the combination of additives depressed CP and PP better than any single additive. The PLM and DSC results suggest that the cocktail additives are most effective when the right molecular structure and optimal concentration are provided. The cocktail mixture achieves then tiny crystals that are prevented from aggregating for an extended temperature range. The results of the study can be directly used for the design of functional and economical CFI from vegetable oils and their derivatives. Author Keywords: Biodiesel, Microstructure, Polymorphism, Pour point depressants, Triacylglycerol, Vegetable Oil Based Crystal Modifier
Novel Functional Materials From Renewable Lipids
Vegetable oils represent an ideal and renewable feedstock for the synthesis of a variety of functional materials. However, without financial incentive or unique applications motivating a switch, commercial products continue to be manufactured from petrochemical resources. Two different families of high value, functional materials synthesized from vegetable oils were studied. These materials demonstrate superior and unique performance to comparable petrochemical analogues currently on the market. In the first approach, 3 amphiphilic thermoplastic polytriazoles with differing lipophilic segment lengths were synthesized in a polymerization process without solvents or catalysts. Investigation of monomer structure influence on the resultant functional behaviour of these polymers found distinctive odd/even behaviour reliant on the number of carbon atoms in the monomers. Higher concentrations of triazole groups, due to shorter CH2 chains in the monomeric dialkynes, resulted in more brittle polymers, displaying higher tensile strengths but reduced elongation to break characteristics. These polymers had similar properties to commercial petroleum derived thermoplastics. One polymer demonstrated self-assembled surface microstructuring, and displayed hydrophobic properties. Antimicrobial efficacy of the polymers were tested by applying concentrated bacterial solutions to the surfaces, and near complete inhibition was demonstrated after 4 hours. Scanning electron microscope images of killed bacteria showed extensive membrane damage, consistent with the observed impact of other amphiphilic compounds in literature. These polytriazoles are suited for applications in medical devices and implants, where major concerns over antibiotic resistance are prevalent. In the second approach, a series of symmetric, saturated diester phase change materials (PCMs) were also synthesized with superior latent heat values compared to commercial petrochemical analogues. These diesters exhibit melting temperatures between 39 °C and 77 °C, with latent heats greater than 220 J/g; much greater than paraffin waxes, which are currently the industry standard. Assessment of the trends between differing monomer lengths, in terms of number of CH2 groups of the 24 diesters synthesized exhibited structure/function dependencies in latent heat values and phase change temperatures, providing an understanding of the influence of each monomer on PCM thermal properties. A synthetic procedure was developed to produce these PCMs from a low value biodiesel feedstock. Application of these PCMs in the thermoregulation of hot beverages was demonstrated using a representative diester. This PCM cooled a freshly brewed hot beverage to a desired temperature within 1 minute, compared to 18 minutes required for the control. Furthermore, the PCM kept the beverage within the desired temperature range for 235 minutes, 40 % longer than the control. Author Keywords: Antimicrobial Surface, Click Chemistry, Green Chemistry, Phase Change Material, Polytriazole, Renewable
Habitat loss and fragmentation can disrupt population connectivity, resulting in small, isolated populations and low genetic variability. Understanding connectivity patterns in space and time is critical in conservation and management planning, especially for wide-ranging species in northern latitudes where habitats are becoming increasingly fragmented. Wolverines (Gulo gulo) share similar life history traits observed in large-sized carnivores, and their low resiliency to disturbances limits wolverine persistence in modified or fragmented landscapes - making them a good indicator species for habitat connectivity. In this thesis, I used neutral microsatellite and mitochondrial DNA markers to investigate genetic connectivity patterns of wolverines for different temporal and spatial scales. Population genetic analyses of individuals from North America suggested wolverines west of James Bay in Canada are structured into two contemporary genetic clusters: an extant cluster at the eastern periphery of Manitoba and Ontario, and a northwestern core cluster. Haplotypic composition, however, suggested longstanding differences between the extant eastern periphery and northwestern core clusters. Phylogeographic analyses across the wolverine's Holarctic distribution supported a postglacial expansion from a glacial refugium near Beringia. Although Approximate Bayesian computations suggested a west-to-east stepping-stone divergence pattern across North America, a mismatch distribution indicated a historic bottleneck event approximately 400 generations ago likely influenced present-day patterns of haplotype distribution. I also used an individual-based genetic distance measure to identify landscape features potentially influencing pairwise genetic distances of wolverines in Manitoba and Ontario. Road density and mean spring snow cover were positively associated with genetic distances. Road density was associated with female genetic distance, while spring snow cover variance was associated with male genetic distance. My findings suggest that northward expanding anthropogenic disturbances have the potential to affect genetic connectivity. Overall, my findings suggest that (1) peripheral populations can harbour genetic variants not observed in core populations - increasing species genetic diversity; (2) historic bottlenecks can alter the genetic signature of glacial refugia, resulting in a disjunct distribution of unique genetic variants among contemporary populations; (3) increased temporal resolution of the individual-based genetic distance measure can help identify landscape features associated with genetic connectivity within a population, which may disrupt landscape connectivity. Author Keywords: conservation genetics, Holarctic species, landscape genetics, peripheral population, phylogeography, wolverine
Ecological and morphological traits that affect the fitness and dispersal potential of Iberian pumpkinseed (Lepomis gibbosus)
The Pumpkinseed (Lepomis gibbosus) is a sunfish that is endemic to eastern portions of Canada and the United States. During the late 19th century, the species was introduced into Europe, and it is now present in over 28 countries. Previous attempts to determine the characteristics that can predict the spread of non-indigenous species have been largely unsuccessful, but new evidence suggests that phenotypic plasticity may help to explain the dispersal and range expansion of some organisms. Experimental comparisons on lower-order taxa have revealed that populations from areas outside of their native range are capable of exhibiting stronger levels of phenotypic plasticity than counterparts from their source of origin. Using Pumpkinseed, I conducted the first native/non- native comparison of phenotypic plasticity in a vertebrate. Progeny from adult Pumpkinseed collected in Ontario, Canada and the Iberian Peninsula (Spain) were reared under variable water velocities, habitat type and competitive pressures, three ecological factors that may affect the dispersal potential of fishes introduced into novel aquatic systems. Differences in phenotypic plasticity, assessed from a morphological perspective, were compared among populations using a traditional distance-based approach. All populations exhibited divergent morphological traits that appeared to be inherited over successive generations. In each experiment, all populations responded to environmental change by developing internal and external morphological forms that, in related taxa, enhance and facilitate foraging and navigation; however, non-native populations always exhibited an overall lower level of phenotypic plasticity. Pumpkinseed from non-native areas may have exhibited a reduction in phenotypic plasticity because of population-based differences. Nevertheless, all Pumpkinseed populations studied were capable of exhibiting phenotypic plasticity to novel environmental conditions, and develop morphological characteristics that may enhance fitness and dispersal in perturbed areas. Author Keywords: Invasive species, Morphology, Phenotypic plasticity, Pumpkinseed sunfish, Reaction norm
Equilibria and distribution models of ionizing organic chemical contaminants in environmental systems
Ionizing organic chemicals are recognized as constituting a large fraction of the organic chemicals of commerce. Many governments internationally are engaged in the time-consuming and expensive task of chemical risk assessment for the protection of human and environmental health. There are standard models that are consistently used to supplement experimental and monitoring data in such assessments of non-ionizing organics by both government regulators and industry stakeholders. No such standard models exist for ionizing organics. Equilibrium distribution models, the foundational equations within multimedia environmental fate models for non-ionizing organics, were developed for the standard series of biphasic systems: air-water, particle-water, air-particle and organic-aqueous phases within living tissue. Multiple chemical species due to the ionization reaction were considered for each system. It was confirmed that, under select conditions, the properties of the neutral parent are sufficient to predict the overall distribution of the organic chemical. Complications due to biotransformation and paucity of identifiable equilibrium distribution data for ionizing organics limited the development of the model for living tissues. However, the equilibrium distributions of ionizing organics within this biotic system were shown to correlate with the abiotic sediment-water system. This suggests that the model developed for particle-water systems should be adaptable to the biotic system as model input and test data become available. Observational data for soil- and sediment- water systems, i.e., particle-water systems, allowed the development of a primarily non-empirical distribution equation for mono-protic acids; this model was almost entirely theoretically derived. The theoretical approach to model development allowed a quantitative assessment of the role of the neutral ion pair, resulting from the complexation of the organic anion with metal cations. To demonstrate the model's potential usefulness in governmental screening risk assessments, it was applied to a broad range of mono-protic organics including drugs and pesticides using standard property estimation software and generic inputs. The order-of-magnitude agreement between prediction and observation typical of the existing models of non-ionizing organics was generally achieved for the chemicals tested. The model was sensitive to the octanol-water partition coefficient of the most populous species. No calibration set was used in the development of any of the models presented. Author Keywords: bioconcentration, chemical equilibrium, environmental modelling, ionizing organic, sorption
Pursuing Different Policy Paths in Long-Term Care
Because federal funding for long-term care was not included as part of Canada's publicly-funded universal health care system, provincial governments have been free to determine how much, or how little, they will rely on the for-profit sector to meet the long-term care needs of their senior populations. The proportion of beds in the for-profit sector differs in each province, demonstrating that policy approaches to this type of care have developed according to distinct provincial political contexts. In this dissertation I explain why governments in two provinces, Manitoba and Ontario, have come to rely on the proprietary sector to markedly different degrees. While in the federation Manitoba stands out for its restrained reliance on this form of care, Ontario stands out for its exceptional dependence on commercial provision. In the chapters that follow I employ an historical institutionalist framework of analysis to explain why these neighbouring provinces initially pursued different policy paths in long-term care and how these paths have been sustained over time. Following an introductory chapter in which I explain the reasons for the marginalization of long-term care within national health policy making, I provide in-depth analysis of these case studies in policy divergence. I argue that contemporary policy differences between these neighbouring provinces cannot be understood in isolation from long-term historical processes. Focusing largely on the period from the 1960s to the 1990s, I emphasize that present differences in ownership are a reflection of the different constellation of actors, events, ideas and institutions that came together at critical junctures in time, and the lasting legacies that these early windows of opportunity for reform have had on subsequent rounds of long-term care policy-making. In each province, diverging ideas about the appropriate role of the for-profit sector in meeting the long-term care needs of an aging population rose to prominence on the political agenda. Over time, rigidities developed in each system, making it difficult for actors advocating for new directions in ownership to realize their ambitions. In both provinces policies put in place at earlier times greatly influenced future political dynamics, altered the guiding principles of government departments and policy makers, provided incentives for different interest group formations, and led to contrasting public expectations about the proper balance of the for-profit and non-profit sectors in long-term care provision. I conclude this dissertation by arguing that its findings can contribute in important ways to present discussions about long-term care reform in Canada generally and about the future role of for-profit providers specifically. Author Keywords: Comparative Politics, Health Policy, Historical Institutionalism, Long-Term Care, Path Dependency, Provincial Politics
Gaagnig Pane Chiyaayong: Forever, We Will Remain, Reflections and Memories
ABSTRACT Gaagnig Pane Chiyaayong: Forever, We Will Remain Reflections and Memories: `Resiliency' Concerning the Walpole Island Residential School Survivors Group Theresa Turmel From 1830 to 1996, Canada pursued a policy of removing Indigenous children from their families and educating them in residential schools. In coming to terms with the harsh and abusive treatment they endured, many survivors from residential schools have formed organizations to support each other and to make their experiences known. This project is a result of a participatory, community-based partnership with one such group in southwestern Ontario, the Walpole Island Residential School Survivors Group (WIRSSG), many of whom attended Shingwauk Indian Residential School. Like most of the survivors of the WIRSSG, I am Anishinaabe but did not attend residential school. The survivors invited me to deeply listen to their life experiences in order to learn about their resiliency. Guided by traditional Anishinaabe teachings and using an Anishinaabe methodology, I interviewed thirteen survivors and considered their life stories within the context of the traditional Anishinaabe life cycle. In their descriptions of resiliency, what became clear to me was that they were describing life force energy. This life force energy is innate and holistic, and can be found within each of us. It manifests within all of our relations: land, animals, plants, ancestors and other people. The life force energy cannot be extinguished but can be severely dampened as was evident in the attempt to assimilate residential school students. From their accounts, we learn that students found ways to nurture their life force energy through relationships and acts of resistance. As they have continued on their life path, they have reclaimed their spirit and today, they are telling their stories and keeping this history alive for the benefit of future generations. Key words: Anishinaabe; Anishinaabe Mino-bimaadiziwin; Residential Schools; Aboriginal Residential School survivors; Indian Residential Schools; Indian Residential School survivors; life force energy; resilience; resiliency; resiliency theory; Walpole Island Residential School Survivors Group; Shingwauk; Shingwauk Indian Residential School Author Keywords: life force energy, residential school survivors, resiliency
Immunogenetic Responses of Raccoons and Skunks to the Raccoon Rabies Virus
Interactions between hosts and pathogens play a crucial role in their adaptation, evolution and persistence. These interactions have been extensively studied in model organisms, yet it is unclear how well they represent mechanisms of disease response in primary vectors in natural settings. The objective of my thesis was to investigate host-pathogen interactions in natural host populations exposed to raccoon rabies virus (RRV). RRV is endemic to North America, that causes acute encephalopathies in mammals and is commonly regarded as 100% lethal if untreated; however variable immune responses have been noted in natural reservoirs. In order to further understand variable immune responses to RRV, my thesis examined (i) potential immunogenetic associations to RRV using genes intimately associated with an immune response, (ii) the nature of immune responses triggered in the host after infection, and (iii) viral expression and genetic variation, to provide insight into factors that may influence RRV virulence. Immunogenetic variation of RRV vectors was assessed using major histocompatibility complex (MHC) DRB alleles. Associations were found between specific MHC alleles, RRV status, and viral lineages. Further, similarities at functionally relevant polymorphic sites in divergent RRV vector species, raccoons and skunks, suggested that both species recognize and bind a similar suite of peptides, highlighting the adaptive significance of MHC and contemporary selective pressures. To understand mechanisms of disease spread and pathogenesis, I screened for variation and expression of genes indicative of innate immune response and patterns of viral gene expression. RRV activated components of the innate immune system, with transcript levels correlated with the presence of RRV. These data indicate that timing of the immune response is crucial in pathogenesis. Expression patterns of viral genes suggest they are tightly controlled until reaching the central nervous system (CNS), where replication increases significantly. These results suggest previous molecular mechanisms for rabies host response derived from mouse models do not strictly apply to natural vector populations. Overall my research provides a better understanding of the immunological factors that contribute to the pathogenesis of RRV in a natural system. Author Keywords: immune response, major histocompatibility complex, rabies, raccoons, skunks, virus
maskihkîyâtayôhkêwina; mashkikiiwaadizookewin
maskihkîyâtayôhkêwina- mashkikiiwaadizookewin: Cree and Anishnaabe Narrative Medicine in the Renewal of Ancestral Literature Jud Sojourn This work represents an experiment in developing Cree and Anishnaabe nation-specific approaches to understanding Cree and Anishnaabe texts. The binding premise that guides this work has to do with narrative medicine, the concept that narrative arts, whether ancestral storytelling or current poetry have medicine, or the ability to heal and empower individuals and communities. As âtayôhkêwin in Cree and aadizookewin in Anishnaabemowin refer to ancestral traditional narratives, and while maskihkiy in Cree, and mashkiki in Anishnaabemowin refer to medicine, maskihkîyâtayôhkêwina and mashkikiiwaadizookewin mean simply `narrative medicine' in Cree and Anishnaabemowin respectively. After establishing a formative sense for what narrative medicine is, this work continues by looking at the bilingual Ojibwa Texts (1917, 1919) transcribed by William Jones in 1903-1905 on the north shore of Lake Superior and in northern Minnesota Anishnaabe communities, those spoken by Anishnaabe community members Gaagigebinesiikwe, Gaagigebinesii, Midaasookanzh, Maajiigaaboo, and Waasaagooneshkang. Then focus then turns to the bilingual Plains Cree Texts (1934) transcribed by Leonard Bloomfield at the Sweet Grass Reserve in Saskatchewan and spoken by Cree community members nâhnamiskwêkâpaw, sâkêwêw, cicikwayaw, kâ-kîsikaw pîhtokêw , nakwêsis, mimikwâs, and kâ-wîhkaskosahk. The themes that emerge from looking at these texts when combined with an appreciation for the poetics of the Cree and Anishnaabe languages provide the foundation for looking at newer poetry including the work of Cree poet Skydancer Louise Bernice Halfe, centering on the contemporary epic prayer-poem The Crooked Good (2007) and the works of Anishnaabe poet Marie Annharte Baker, focusing on Exercises in Lip Pointing (2003). Each poet emerged as having an understanding her own role in her respective nation as renewing the narrative practices of previous generations. Understandings of the shape or signature of each of the four works' unique kind of narrative medicine come from looking at themes that run throughout. In each of the four works the maskihkîyâtayôhkêwina - mashkikiiwaadizookewin, the narrative medicine they express occurs through or results in mamaandaawiziwin in Anishnaabemowin or mamâhtâwisiwin, in Cree - the embodied experience of expansive relationality. Keywords: Cree, Anishnaabe, nêhiyawêwin, Anishnaabemowin, narrative medicine, traditional stories, poetics, poetry, literary criticism, literary nationalism, Indigenous, indigenist. Author Keywords: Anishnaabe, Anishnaabemowin, Cree, Indigenous, nêhiyawêwin, Poetics
Maintaining Balance in Times of Change
Abstract Maintaining Balance in Times of Change: An Investigation into the Contemporary Self-Regulatory Dynamics that Operate in and around First Nations Traditional Healing Systems The evolution of health regulation processes in Canada has focused on the development of standards of practice premised upon the principle of `do no harm' and the approval of these by government regulatory agencies. This thesis examines three emerging communities of practice that bring traditional indigenous knowledge and indigenous healers forward into health care and their approaches to regulation. The results indicate that surrounding contexts of meaning influence understandings about self-regulation and that these understandings are dynamic because contemporary practices of First Nations traditional healing can occur in different contexts. The study cautions that unless we remain close to these `healer centred' contexts, there is no guarantee that the self-regulatory value systems stemming from modern Western medical communities of practice will not be applied by default or that the emerging `integrative' models of self-regulation developed between governments and First Nations will continue to reflect First Nations' understanding of self-regulation. Author Keywords: health and wellness, indigenous, self-determination, self-regulation, traditional healing
Archaeology of Vagabondage
My research examines the figure of the 'vagabond' as a case study to illustrate how 'modern' perception of the 'vagabond' has depleted the diversities in its 'pre-modern' counterparts. It argues that the paranoia towards the 'vagabond' was inherited from the west out of the colonial contact leading to the birth of the nation-state and its liaison with 'instrumental rationality' during the high noon of advanced industrial capitalism, while (quasi-religious) itinerancy, on the contrary, had always been tolerated in 'pre-modern' India. The problems I am addressing are: What is the line of thread that separates the 'traveler' from the 'vagabond', the 'explorer' from the 'wanderer'? How do we then politically account for the historic 'ruptures' in the vagabond having been tolerated in the ancient 'Indic' thought [cf. Manusmriti, Arthshastra], encouraged in early Buddhist discourse [cf. Samannaphala Sutta], revered as the 'holy Other' in the Middle Ages [cf. Bhakti-Sufi literature], and eventually marginalized in the 'modern'? While considering issues of cultural differences, my thesis points to how the epistemic shifts from the classical to the medieval, from the medieval to the modern radically alter the value system immanent in the figure of the 'vagabond'. The research argues that the cultural baggage that the expression 'vagabond' is generally associated with, is a product of a specific western/utilitarian value system, which is a distinct 'cultural' category of the 'modern' west that had no resonance in 'pre- modern' India, and hence cannot be necessarily universalizable. The project works in a number of registers: historical, archival, cultural, philosophical and representational, involves analysis of literary, filmic texts, also legislative documents, and is genuinely interdisciplinary in nature. As of discourse analysis, the project studies the politics of cultural representations both of and by 'vagabonds'. Author Keywords: 1943 Bengal Famine, Homelessness, India, Vagabond, Vagrancy, Vagrancy Act
Rewiring the State
ABSTRACT Rewiring the State: The Privatization of Information Technology in the Ontario Public Service (1972-2003) David Rapaport Senior managers in the Ontario Public Service (OPS) and neo-liberal public policy advocates rationalize the privatization of Information Technology (IT) as an organizational quest for new efficiencies, specifically efficiencies imported from market economies. The findings of the research for this study indicate that IT privatization frequently results in inefficiencies, dependencies and a loss of core skills. The explanation for widespread IT privatization must be sought elsewhere. This study researches and depicts two related IT developments. The first development is the evolution of IT privatization from the earlier practice of body-shopping, i.e. the hiring on contract of IT consultants to the more complex public private partnership. This evolution is a reflection of the maturation of privatization. Body-shopping informs the alienation of IT skills from the public sector, the shaping of a labour hierarchy based on skills distribution, and the foundation for the public-private partnership. The second development, the evolution of OPS management attitudes towards IT privatization, is a reflection of growing neo-liberal hegemony. Archival research indicates middle management disdain towards excessive IT privatization in the early 1980's; particularly its high costs, loss of skills and growing dependency on external private sources. By the ii late 1990's, parliamentary committee transcripts indicate IT management acceptance of more excessive IT privatization. As neo-liberal practice became more accepted and as governments and central ministries pressured line ministries through budgetary and organizational controls, IT managers accepted their new roles as authors of RFP's and tenders of public sector work. The IT service providing industry gladly bid on contracts and acquired the new skills required for future IT projects, exacerbating the provision/dependency cycle. Furthermore, the new technologies provided an ideological smokescreen of technological necessity to conceal the market forces that promoted and benefitted from IT privatization. "Why do managers in the Ontario Public Service privatize the production of Information Technology systems?" The dissertation has two tasks when answering this central question. First, it must refute the efficiency arguments. Second, it must formulate an answer within the context of neo-liberal state transformation, new investment strategies of IT service providing corporations and a restructured IT labour hierarchy. Author Keywords: neo-liberalism, New Public Management, Ontario, privatization, public private partnership, public sector


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