Graduate Theses & Dissertations

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Genome annotation, gene characterization, and the functional analysis of natural antisense transcripts in the fungal plant pathogen Ustilago maydis
Ustilago maydis (DC) Corda is the causal agent of 'common smut of corn'. Completion of the U. maydis lifecycle is dependent on development inside its host, Zea mays. Symptoms of U. maydis infection include chlorosis and the formation of tumours on all aerial corn tissues. Within the tumours, thick-walled diploid teliospores form; these are the reproductive and dispersal agent for the fungus. U. maydis is the model to study basidiomycete biotrophic plant-pathogen interactions. It holds this status in part because of the completely sequenced 20.5 Mb genome; however, thorough genome annotation is required to fully realize the value of this resource. The research presented here improved U. maydis genome annotation through the analysis of cDNA library sequences and comparative genomics. These analyses identified and characterized pathogenesis-related genes, and identified putative meiosis genes. This enabled the use of U. maydis as a model for investigating 'host-induced' meiosis. Further, the cDNA library analyses identified non-coding RNAs (ncRNAs) and natural antisense transcripts (NATs). NATs are endogenous RNA molecules with regions complementary to a protein-coding transcript. Although NATs have been identified in a wide variety of mammals, plants, and fungi, very few have been functionally characterized. Over 200 U. maydis NATs were annotated by analyzing full-length cDNA sequences. NAT structural features were characterized. Strand-specific RT-PCR was used to detect NATs in U. maydis and in a related smut fungus, U. hordei. The data supported a common role for NATs in smut teliospore development, independent of the RNA interference pathway. Analysis of the expression of one U. maydis NAT, as-um02151, in haploid cells, led to a model for NAT function in U. maydis during teliospore dormancy. This model proposed NATs facilitate the maintenance of stored mRNAs through the formation of double-stranded RNA. In testing this model, it was determined that the deletion of two separate upstream regulatory regions, one of which contained a ncRNA (ncRNA1), altered NAT levels and decreased pathogenesis. These studies strengthened U. maydis as a model organism, and began the functional investigation of NATs in U. maydis, which identified a new class of fungal pathogenesis genes. Author Keywords: cDNA library analysis, genome annotation, mRNA stability, natural antisense transcripts, pathogenesis, Ustilago maydis
Abject Utopianism and Psychic Space
This dissertation utilizes the psychoanalytic theories of French psychoanalyst Julia Kristeva as a lens through which to read the novels of American author Samuel R. Delany. I argue that concepts proper to Kristeva's work--namely abjection and/or the abject--can provide a way to think what it might mean to be utopian in the 21st century. Delany's novels are received historically, which is to say his work speaks from a certain historical and cultural viewpoint that is not that of today; however, I claim that his novels are exceptional for their attempts to portray other ways of being in the world. Delany's novels, though, contain bodies, psychologies, and sexualities that are considered abject with respect to contemporary morality. Nonetheless, this dissertation argues that such manifestations of abject lived experience provide the groundwork for the possibility of thinking utopianism differently today. Throughout, what I am working toward is a notion that I call Abject Utopianism: Rather than direct attention toward those sites that closely, yet imperfectly, approximate the ideal, one should commit one's attention to those sights that others avoid, abscond, or turn their nose up at in disgust, for those are the sites of hope for a better world today. Author Keywords: Abject, Delany, Kristeva, Literary Criticism, Psychoanalysis, Utopia
Cooperation and Conflict
This study examines interaction and accommodation between Western Christians and Muslims in the Levant between the Second and Third Crusades, 1145 to 1192, examining three groups: short term crusaders, members of military orders, and permanent settlers. While members of these groups possessed several personal and group identities, most shared a prescriptive religious identity that encouraged a common goal: holy war for the protection of the Holy Land from Muslims, whom they identified as a distinct, enemy `other.' Despite these prescriptive beliefs, when Christians came into contact with Muslims, particularly following longer and more varied contact, most engaged in some convergent accommodation, such as diplomatic accommodation, development of shared languages and gestures, or admiration for chivalric qualities. Those settled in the Levant accepted the existing economic and social structures, assuming the roles of previous elites, adopting certain local customs, sharing sacred spaces, medical knowledge, or even developing personal ties with Muslims. Author Keywords: Accommodation, Christianity, Crusades, Identity, Islam
AN EXAMINATION OF THE FUNERARY OFFERINGS PLACED IN MYCENAEAN CHAMBER TOMBS DURING THE PALATIAL AND POSTPALATIAL PERIODS IN THE AEGEAN
Mortuary remains comprise a large part of the archaeological record for the Late Bronze Age in the Aegean. By the Palatial period, chamber tombs became the most common burial type on the Mycenaean Mainland, with their popularity continuing into the Postpalatial period. In addition, a single chamber tomb could be reused for as many as ten generations, resulting in large collections of burials and offerings. On account of the prolific use and reuse of chamber tombs, they provide an abundance of data for studying the mortuary rituals performed by the Mycenaeans during the Palatial and Postpalatial periods. The purpose of this study is three fold: to test the theory that the Mycenaean palatial systems influenced the types of offerings placed in the chamber tombs; to assess the validity of previously stated claims that the offerings placed in the chamber tombs represent funerary rituals, and if so, what type(s) of rituals?; and to establish whether Mycenaean mortuary archaeology is sufficiently well recorded to support a meaningful analysis of variation in funerary depositional patterning. The results of this study provide insight into the nature of the Mycenaean mortuary rituals for chamber tombs. Author Keywords: Chamber Tombs, Late Helladic, Mortuary rituals, Mycenaean, Palatial period, Postpalatial period
Purification and Identification of Selenium-containing C-phycocyanin from Spirulina
Selenium is an essential trace nutrient to many organisms, yet in high concentrations it is toxic. Organic selenium is more bioavailable to aquatic biota than inorganic selenium, but is usually found in much lower concentrations. Algae are known to biotransform inorganic selenium into several organo-selenium compounds, but it is unknown whether any of these bioaccumulate in the food chain. In this study, selenium was incorporated into the methionine residues of an algal photosynthetic protein, c-phycocyanin from Spirulina spp. The extent of selenium incorporation was quantified by inductively coupled plasma-mass spectrometry (ICP-MS), and the protein was identified using electrospray mass spectrometry (ES-MS). C-phycocyanin was isolated and purified from Spirulina with a final recovery of 20-30 % of the total c-phycocyanin present. Selenomethionine replaced 92.8% ± 1.22 of the methionine residues in c-phycocyanin when grown in 2.5 ppm sodium selenite. ES-MS was used to obtain protein spectra, and pure c-phycocyanin was identified. Data of full scans provided estimated masses of both protein subunits--α-chain measured at 18,036 Da; β-chain measured at 19,250 Da--close to the theoretical masses. Protein fragmentation by collision-induced dissociation and electron capture dissociation provided approximately 52 % amino acid sequence match with c-phycocyanin from Spirulina platensis. This study demonstrates the incorporation of selenium into an algal protein, and the identification of c-phycocyanin using electrospray ionization-mass spectrometry. Author Keywords:
THE PROPENSITY TOWARD EXTREMIST MIND-SET AS PREDICTED BY PERSONALITY, MOTIVATION, AND SELF-CONSTRUAL
ABSTRACT The Propensity Toward Extremist Mind-Set as Predicted by Personality, Motivation, and Self-Construal Nick Fauset Multivariate regression analyses were used to determine the effects of Personality (Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness), Motivation (External, Amotivation, Intrinsic, and Identified), and Self-Construal (Independent and Interdependent) on three domains of Extremist Mind-Set (Proviolence, Vile World, and Divine Power). Participants consisted of first year undergraduate students (209 females, 76 males) enrolled in Introductory Psychology (N=279) and/or Introductory Economics (N=7), whom participated for course credit. The Motivation measure was problematic for students to complete and this variable was dropped from the model due to missing data. Decreases in Neuroticism, Openness, Agreeableeness, and Interdependent were significantly correlated with increases in Proviolence. Decreases in Agreeableness were correlated with increases in Vile World. Decreases in Openness, and increases in Agreeableness and Interdependent were significantly correlated with increases in Divine Power. These observations provide an interesting perspective on the types of Canadian undergraduate students who are more likely to score highly on measures of Extremism. Keywords: Militant Extremist Mental Mind-Set, Extremism, Personality, Five Factor Model, Motivation, Intrinsic, Extrinsic, Self-Construal, Independent, Interdependent Author Keywords: Extremism, Militant Extremist Mental Mind-Set, Motivation, Personality, Self-Construal
Exploring Indigenous Contributions to (Indigenization of) the City of Saskatoon's 2012-2022 Strategic Plan
The self-determining autonomy of urban Aboriginal communities in Canada's Prairie Provinces can be strengthened at the local scale through decolonized municipal governance frameworks. The City of Saskatoon's Strategic Plan 2012-2022 is highlighted to explore two interrelated questions: do Saskatoon's Aboriginal engagement strategies represent a co-produced or indigenized mainstream planning and policy-making process? Does the potential indigenization of municipal planning and policy-making represent a promising pathway to facilitate local decolonization through collaborative municipal-Aboriginal governance in Saskatoon? Results from qualitative interviews reveal that the City of Saskatoon's distinctive Aboriginal engagement strategies were not entirely meaningful for participants, though the planning process included elements that, if expanded upon, could deepen co-production. Indigenization through co-production necessitates a thorough integration of Aboriginal community input at every stage of a planning and policy-making process, shared control and decision-making mechanisms between municipal governments and Aboriginal communities, and ancillary considerations for increased Aboriginal representation and participation in the administrative and political functions of City Hall. Author Keywords: aboriginal governance, decolonization, indigenization, policy co-production, self-determination, strategic municipal planning
Widespread changes in growth, diet and depth distribution of lake whitefish (Coregonus clupeaformis) in the Great Lakes are linked to invasive dreissenid mussels
Recent declines in growth and condition of Great Lakes' lake whitefish (Coregonus clupeaformis) have been linked to ecosystem-wide changes stemming from the invasion of dreissenid mussels. To test the influence of invasive mussels on this commercially important coregonid species, we collected archived scale samples from ten Great Lake locations and analyzed long-term changes in growth rates, delta 13C and delta 15N stable isotope ratios before and after mussel establishment. There was a decrease in pre-maturation growth after establishment in all four locations where we examined back-calculated growths. In six of the seven locations with dreissenid populations, a significant increase in delta 13C and a significant decrease in delta 15N was found. In dreissenid-absent locations of Lake Superior, we did not see changes in growth or isotope ratios indicative of a major regime shift. Observed shifts in isotopic signatures provide evidence for an increased reliance on nearshore food sources and shallower depth distribution as a result of dreissenids, which likely contributed to lowered growth of lake whitefish. Author Keywords: Diporeia, Dreissenids, food web, Great Lakes, invasive species, lake whitefish
Development and Use of Passive Samplers for Monitoring Dissolved and Nanoparticulate Silver in the Aquatic Environment
Silver nanoparticles (nAg) are the largest and fastest growing class of nanomaterials, and are a concern when released into aquatic environments even at low μg L-1+). Diffusive gradient in thin films (DGT) with a thiol-modified resin were used to detect labile silver and carbon nanotubes (CNT-sampler) were used to measure nAg. Laboratory uptake experiments in lake water provided an Ag+ DGT diffusion coefficient of 3.09 x 10 -7 cm2s-1 and CNT sampling rates of 24.73, 5.63, 7.31 mL day-1, for Ag+, citrate-nAg and PVP-nAg, respectively. The optimized passive samplers were deployed in mesocosms dosed with nAg. DGT samplers provided estimated Ag+ concentrations ranging from 0.15 to 0.98 μg L-1 and CNT-samplers provided nAg concentrations that closely matched measured concentrations in water filtered at 0.22 μm. Author Keywords: ICP-MS, mesocosms, nanoparticles, nanosilver, passive sampling
gi-mi-ni-go-wi-ni-nan o-gi-ma-wi-win zhigo o-gi-ma-win (The gifts of traditional leadership and governance)
ni' o-nah-ko-nah ah-di-so-kah-nahg zhigo di-bah-ji-mo-wi-nan g'dah mi-kwe-ni-mah-nahn obwandiacbun (nigig), tecumthabun (mizhibizhi), miinwaa shingwaukbun (ah-ji-jawk) (I ceremonially call upon the stories, the sacred and spiritual narratives and stories of personal experience... In the spirit of obwandiac, tecumtha and shingwauk) gi-mi-ni-go-wi-ni-nan o-gi-ma-wi-win zhigo o-gi-ma-win (The gifts of traditional leadership and traditional governance) explores anishinabe o-gi-ma-wi-win (traditional leadership and to be esteemed) from the point of view of obwandiac (nigig) in 1763, tecumtha (mizhibizhi) and shingwauk (ah-ji-hawk) in 1812 and 1850 respectively. It also examines the political and social significance of anishinabe o-gi-ma-win (traditional governance) and the n'swi-ish-ko-day-kawn anishinabeg o'dish-ko-day-kawn (Three Fires Confederacy) during the time of these esteemed leaders. The use of our ah-di-so-kah-nahg (sacred and spiritual stories), di-bah-ji-mo-wi-nan (stories of personal experience and reminiscences) and ah-way-chi-gay-wi-nan (moral stories) provides the opportunity to show how anishinabe people used different narratives to ah-way-chi-gay-win (teach by telling stories). In listening to these personal and intimate stories we have an opportunity to understand and explore these concepts of o-gi-ma-wi-win (traditional leadership and to be esteemed) and o-gi-ma-win (traditional governance). The first layer to this distinct way of knowing embodies anishinabe nah-nah-gah-dah-wayn-ji-gay-win (how we come to think this way about our reality and epistemology) and is expressed to us within our gah-wi-zi-maw-ji-say-muh-guhk (creation and stories of origin) and miskew ah-zha-way-chi-win (blood memory and the act of flowing). It states explicitly that we have always known where we came from, who we are, and how we fit into this world. anishinabe i-nah-di-zi-win (our way of being and way of life and ontology) lends voice to the second layer of anishinabe kayn-daw-so-win (traditional knowledge), which defines the responsibilities and expectations of anishinabe society, leadership and governance. Our ni-zhwa-sho gi-ki-nah-mah-gay-wi-nan (seven teachings), ni-zhwa-sho o-na-sho-way-wi-nan (seven sacred laws) and the relationship of the do-daim-mahg (clan system) are described within anishinabemowin, the language of our ceremonies and of the jeeskahn (shake tent). Harry Bone (2011)1, an elder from Keeseekoowenin First Nation suggests that ah-zhi-kay-ni-mo-nahd-a-di-sid bay-mah-di-sid (how we use our way of doing, thinking, ceremony and spirituality to find answers and methodology) represents a third layer that provides us with the ways and means to help us understand the essence of anishinabe nah-nah-gah-dah-wayn-ji-gay-win (how we come to think this way about our reality and epistemology and i-nah-di-zi-win (our way of being and way of life and ontology). This represents the literal and metaphoric o-dah-bah-ji-gahn (sacred bundle) and traditional approach that provides this narrative with the means to explore the ideas of leadership and governance from within a traditional construct. He adds that our spirituality and manitou kay-wi-nan (ceremonies) will be clearly defined and shared within this o-dah-bah-ji-ji-gahn (sacred bundle). It helps establish the spiritual core for this narrative. These anishinabe approaches to methodology (intimate conversations, family history and ceremony) are used to tell a story that mirrors the academic construct of interviews and document analysis. Therefore, the o-dah-bah-ji-gahn (sacred bundle) provides the nay-nahn-do-jee-kayn-chi-gayd (to dig around and research) tools to have this discussion exploring the traditional construct of anishinabe o-gi-ma-wi-win (traditional leadership and to be esteemed) and o-gi-ma-win (traditional governance). Lastly, it is important to understand that this traditional approach shows how these narratives are in-and-of-themselves powerful strategies in understanding anishinabe ah-yah-win (way of being and existence) and gah-gi-bi-i-zhi-say-mah-guhk (history). mii i'i-way anishinabe i-zhi-chi-gay-win (This is the anishinabe way) zhigo mii'iw eta-go o-way neen-gi-kayn-dahn zhigo ni-gi-noon-dah-wah (This is as much as I know and have heard) 1 Bone, Harry (Personal Communication) 2011. Author Keywords:
Motivating Policy Responses to Climate Change
This research investigates urban climate governance through a case study of climate change adaptation policy making in the Canadian municipality of Vancouver, British Columbia (BC). It investigates the context in which the City of Vancouver was motivated to develop its climate change adaptation strategy (CCAS) by exploring the motivating factors and drivers behind the formulation of this plan. The research approach involved content analysis of policy documents underlying the CCAS as well as interviews with key politicians and policy makers familiar with the strategy. I conceptualize the development of the CCAS using Kingdon's Multiple Streams Framework, leading me to conclude that the convergence of three streams, namely: 1) knowledge of local climate change impacts and their cost to city assets, 2) political leadership and 3) green policy coordination in the City of Vancouver, created an opportunity that was seized upon by policy champions to address adaptation. Author Keywords: adapting cities to climate change, climate change adaptation policy, climate change adaptation policy formulation, local climate governance, municipal adaptation plan, urban climate governance
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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Format: 2023/12/06