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This thesis investigated coloured and fluorescent dissolved organic matter in the Canada Basin, Arctic Ocean from 2007 to 2017. The first interannual time-series of its kind in the Canada Basin incorporated the use of EEM-PARAFAC to validate a seven-component model. Statistical temporal tests revealed (1) an increasing protein-like intensity in the upper polar mixed layer (UPML); (2) increasing intensities of humic-like components in the halocline due to increasing freshwater content; and (3) no change in DOM composition in deeper Atlantic waters (AW) congruent with the long residence time of the water mass (> 30 years). The significant decline in sea ice concentration was related to a decrease in humic-like FDOM due to enhanced photodegradation and an increase in protein-like FDOM, likely the results of increased biological activities in surface layers. This research provides evidence that the changes in physical and biological environment in the Arctic regions have already profound impacts on the composition and distribution of FDOM.

Author Keywords: absorbance, Arctic Ocean, dissolved organic matter, fluorescence, parallel factor analysis, time-series

The residential sector is a major consumer of electricity, and its demand will rise by 65 percent by the end of 2050. The electricity consumption of a household is determined by various factors, e.g. house size, socio-economic status of the family, size of the family, etc. Previous studies have only identified a limited number of socio-economic and dwelling factors. In this thesis, we study the significance of 826 geodemographic factors on electricity consumption for 4917 homes in the City of London. Geodemographic factors cover a wide array of categories e.g. social, economic, dwelling, family structure, health, education, finance, occupation, and transport. Using Spearman correlation, we have identified 354 factors that are strongly correlated with electricity consumption. We also examine the impact of using geodemographic factors in designing forecasting models. In particular, we develop an encoder-decoder LSTM model which shows improved accuracy with geodemographic factors. We believe that our study will help energy companies design better energy management strategies.

Author Keywords: Electricity forecasting, Encoder-decoder model, Geodemographic factors, Socio-economic factors

This MA thesis discusses the applications of immersive virtual reality technologies as a tool for studying archaeological excavation processes. The excavation of a structure at the Nassau Mills, a twentieth century milling complex in Peterborough, Ontario, is used as the case study. Structure from Motion (SfM) photogrammetry is used to digitize each excavation day as 3D models. These excavation days are visualized in the Nassau Mills Pavilion, which enables users to revisit the site on each excavation day, and view and measure structural contexts. This thesis explores a number of theories including: affordance theory, phenomenology, theories of perception, and spatial accuracy. It also discusses multi-user presence, spatial thinking, and wayfaring as notions for improving the way users collaborate, share, and study digitized archaeological data in virtual environments. This thesis offers new approaches to using supplementary digital recording techniques for archaeological excavation while providing a new VR collaborative platform for digitizing and disseminating archaeological data.

Author Keywords: Archaeological Database, Digital Archaeology, Multi-User Collaboration, SfM Photogrammetry, Spatial Thinking, Virtual Reality

Universities produce a significant and increasing share of basic research that is later commercialized by firms. We argue that the university's prominence as a producer of basic research is the result of a differential efficiency in research production that cannot be replicated by firms or individual agents - teaching. By using research accomplishments to signal knowledge and attract tuition-paying students, universities are uniquely positioned to undertake certain types of research projects. However, in a market for innovation without patent rights, a significant and increasing number of basic research projects, that are social welfare improving, cannot be initiated by firms or universities. The extension of patent rights to university-generated research elegantly redresses this issue and leaves us to ponder important questions about the future of our innovation-driven economies.

Author Keywords: Innovation, Intellectual Property Rights, Research, Science Technology and Innovation Policy

Euglena gracilis is an enigmatic and adaptable organism that has great bioremediationpotential and is best known for its metabolic flexibility. The research done in this dissertation addresses (1) how growth conditions impact cellular composition, and (2) how chemometric approaches (such as statistical design of experiments and artificial neural networks) are viable alternatives to the conventional biosorption models for process optimization. Using high-resolution mass spectrometry for biosorbent characterization is a powerful way to assess the chemical characteristics of lyophilized and fractionated cells with high precision, especially to screen for compound classes that may have potentiality for rare earth element removal. Growth conditions impacted cellular composition and separated size fractions of cells yielded different molecular/chemical properties as described by compositional abundances, thus different biosorptive potential. Untargeted analysis demonstrated that exponential dark-grown cells with glucose supplementation were abundant in polyphenolic- and carbohydrate-like compounds, molecular species highly involved in rare earth element binding. Light grown cells had more heterogeneity and the highest molecular weighted fractions from light grown cells (fraction D) had the most abundances of polyphenolic- and protein-like structures. Chemometric modeling used identified the best and worst conditions for iii dysprosium sorption and showed that pH had the most significant influence on bioremoval. Bioremoval ranged from 37% at pH 8 to 91% at pH 3 at Dy concentration ranging from 1 to 100 μg L-1. The work presented in the PhD dissertation will aid in understanding the chemical characteristics of biosorbents by using a Van krevelen analysis of elemental ratios whether algal cells are grown in different environmental growth conditions, or when algal cell are size fractionated. This is especially applied for the screening for metal binding potentiality to Dysprosium. Chemometric methods provide an alternative method for the investigating factors for bioremoval, and applications for process optimization and for real-world applications. This dissertation will aid in understanding chemical characteristics when a biosorbent is grown in a given condition and which factors are important for rare earth element (REE) bioremoval. The significance of this work aims to look for alternate ways to screen biosorbents and using a more efficient experimental design for REE bioremoval.

Author Keywords: bioremoval, biosorption, chemometrics, dysprosium, euglena, mass spectrometry

Fishers (Pekania pennanti) were extirpated from many parts of Ontario in the early 20th century, but as of the early 2000s the species had recolonized most of its historical range. While the primary population genetic structure of fishers in central and eastern Ontario has not changed drastically over the past ten years, we did find evidence of increased secondary structure and a reduction in northward movement from southeastern Ontario, a site of recent immigration from the Adirondacks in northern New York. This may be indicative of a reduction in density and thus in density-dependent migration, or it may be a consequence of the population reaching equilibrium following a period of rapid expansion associated with recolonization. We also observed no variation within central and eastern Ontario at 14 of 15 candidate functional loci we screened, suggesting possible directional or stabilizing selection and a lack of adaptive potential.

Author Keywords: fisher, functional genes, Ontario, Pekania pennanti, population genetics, recolonization

Early diagnosis of autism spectrum disorder (ASD), while providing many benefits, presents challenges to clinicians such as predicting the stability of symptoms. Accurately predicting symptom severity allows clinicians to confidently diagnose and assign the most appropriate treatment. Little research exists to date to predict symptom severity in children with ASD who have not been exposed to treatment. The present file review examined prelinguistic skills as predictors of symptom severity in a group of young children (age: 18 – 64 months) with ASD (n = 199) who had not been exposed to significant levels of treatment. Hierarchical regression analyses demonstrated that of the two core diagnostic features (social communicative deficits and restricted repetitive behaviours), social communicative skills best predicted symptom severity. Furthermore, social communicative gestures predicted symptom severity after age, adaptive behaviour, restricted repetitive behaviours, and functional gestures had been accounted for.

Author Keywords: autism, gestures, predictors, prelinguistic, social communicative, symptom severity

The appearance of a two-dimensional electron gas (2DEG) in oxide interfaces between strontium titanate (STO) and other materials has become a major area of study. The behaviour of the 2DEG in STO is not well understood in part because the dielectric properties of STO are not well characterized. The differential susceptibility has a major impact on the electric fields within strontium titanate, and therefore to understand the 2DEG a better understanding of the susceptibility is needed. An expression for the soft mode phonon frequency of bulk strontium titanate is derived and used to model the susceptibility as a function of spatially homogeneous electric field, temperature and wavevector. This model is used to discuss the effect of spatially inhomogeneous electric fields and the local vs. nonlocal nature of the susceptibility. The critical exponents and the free energy are determined and discussed.

Author Keywords: critical exponents, differential susceptibility, quantum paraelectric, strontium titanate

Cytokinin biosynthesis in organisms aside from plant species has often been viewed as a byproduct of tRNA degradation. Recent evidence suggests that these tRNA degradation products may actually have a role in the development of these organisms, particularly fungi. This thesis examines the importance of cytokinins, a group of phytohormones involved in plant cell division and differentiation as well as the phytohormone abscisic acid, involved in plant response to environmental factors, and their presence and role in fungi.

An initial survey was conducted on 20 temperate forest fungi of differing nutritional modes. Using HPLC-ESI MS/MS, cytokinin and abscisic acid were detected in all fungi regardless of their mode of nutrition or phylogeny. The detection of the same seven CKs across all fungi suggested the existence of a common CK biosynthetic pathway and dominance of the tRNA pathway in fungi. Further, the corn smut fungus Ustilago maydis is capable of producing CKs separate from its host and different U. maydis strains induce disease symptoms of differing severity. To determine if CK production during infection alters disease development a disease time course was conducted on cob tissue infected with U. maydis dikaryotic and solopathogenic strains. Dramatic changes in phytohormones including an increase in ABA followed by increases in cisZCKs were detected in tumour tissue particularity in the more virulent dikaryon infection, suggesting a role for CKs in strain virulence. Mining of the U. maydis genome identified a sole tRNA-isopentenyltransferase, a key enzyme in CK biosynthesis. Targeted gene deletion mutants were created in U. maydis which halted U. maydis CK production and decreased pathogenesis and virulence in seedling and cob infections. CK and ABA profiling carried out during disease development found that key changes in these hormones were not found in deletion mutant infections and cob tumour development was severely impaired. These findings suggested that U. maydis CK production is necessary for tumour development in this pathosystem. The research presented in this thesis highlights the importance of fungal CKs, outlines the dominant CK pathway in fungi, identifies a key enzyme in U. maydis CK biosynthesis and reveals the necessity of CK production by U. maydis in the development of cob tumours.

Author Keywords: abscisic acid, cytokinins, high performance liquid chromatography-electrospray ionization tandem mass spectrometry, tRNA degradation pathway, Ustilago maydis, Zea mays

This thesis project explores landowner experiences of wind energy development through an inductive qualitative case study in Huron County, Ontario. The research included in-depth interviews with landowners focused on landscape and community change, participant observation of Environmental Review Tribunals (ERT), the gathering of participant photos, as well as relevant government and industry documents and media reports. The iterative data gathering and analysis were supported by my observations and reflections while living in affected communities and talking to participants. The study demonstrates how the health debate over wind can inform divisions between neighbours, that local politics have been given a token role as a place for resistance to wind energy development that fails to meaningfully influence projects, and that appeals are legalistic and do not provide an outlet, or place for appellants to be heard. Furthermore, the felt experience of tight knit and fragile communities were disrupted through land leases, as well as changes to the landscape. These disruptions impacted connections to, and associations with place, and are shown to have had negative emotional and physical impacts on some individuals. Supporters of wind development tied their mostly positive views of landscape change to a sense of disruption generally throughout the community. Insights from the research lead to a set of suggested actions that might improve the current situation at the levels of provincial policy, planning, local governance and industry practice.

Keywords: wind energy policy, planning, landscape, Ontario, rural communities

Author Keywords: Affect, landscape, Ontario, planning, Rural communities, Wind energy policy