application/pdf

I have developed and improved a coherent anti-Stokes Raman scattering (CARS) microscope based on the spectral focusing (SF) technique. The CARS microscope uses an 800 nm oscillator and a photonic crystal fibre module to generate the supercontinuum Stokes. The photonic crystal fibre was originally designed to generate light beyond 945 nm which is useful for CARS microscopy in the CH/OH frequencies but essentially prevents access to the important fingerprint region at lower frequencies. With expert and nontraditional approaches to generating supercontinuum with sufficient power at wavelengths below 945 nm, I substantially extend the usefulness of the module for SF-CARS microscopy deep into the fingerprint region. Moreover, with the invention of a dynamic supercontinuum generation scheme we call "spectral surfing," I improve both the brightness of the CARS signal and extend the accessible CARS frequency range to frequencies as low as 350 cm$^{-1}$ and as high as 3500 cm$^{-1}$---all in a single scan-window. I demonstrate the capabilities of our broadband SF-CARS system through CARS and four-wave mixing hyperspectroscopy on samples such as astaxanthin, lily pollen and glass; liquid chemicals such as benzonitrile, nitrobenzene and dimethyl sulfoxide; and on pharmaceutical samples such as acetaminophen, ibuprofen, and cetirizine. Furthermore, In search of more useful Stokes supercontinuum sources, I compare the performance of two commercial photonic crystal fibre modules for use in SF-CARS applications, ultimately finding that one module provides better spectral characteristics for static supercontinuum use, while the other provides improved characteristics when spectral surfing is implemented.

Author Keywords: coherent anti-Stokes Raman scattering, nonlinear microscopy, scanning microscopy, spectroscopy, supercontinuum generation, vibrational spectroscopy

The Royal Philanthropic Society (RPS) was the first institution in England to care for young offenders. While historians have demonstrated the legal importance of this institution, none have examined the experience of the youths it attempted to reform. The admission registers of the RPS reveal the importance of adults and peers in the experiences of the inmates of the institution, as both could be sources of conflict and support. Youths could express power over their own lives by resisting the authority of adults, but also by conforming to the rules of the RPS. Inmates could restrict the choices of their peers by working with the RPS, but also through peer pressure or violence. Networks of collaboration and youth culture could also exert a positive impact on peers. Because this thesis represents male youths as actors, it makes a significant addition to recent histories emphasizing the impact of the subaltern groups on eighteenth-century reform movements.

Author Keywords: Conformity, Juvenile Delinquency, Penal Reform, Power Relationships, Royal Philanthropic Society, Youth Culutre

This study identifies and examines interlinkages between climate change and sustainable development, environmental security, and adaptive capacity through a case study of two communities in the Inuvialuit Settlement Region: Inuvik and Tuktoyaktuk. It seeks to understand how these two communities perceive climate change and define sustainable development, particularly in relation to oil and gas development. This thesis discusses the constraints that may be arising for local communities to benefit from emerging opportunities due to competing notions of sustainable development and environmental security. The findings indicate how notions of environmental security and sustainable development act upon multiple levels to impact the adaptive capacity of communities in the Arctic. The general findings also suggest that regionally specific understandings of sustainable development, sustainability, and environmental security need to be acknowledged in order to develop successful governance coordination and cooperation strategies and paradigms related to economic, social, infrastructure and environmental issues in the NWT and the Canadian Arctic.

Author Keywords: Arctic, Beaufort Sea, climate change, Environmental Security, Inuvialuit, Sustainable Development

Invasive species that alter habitats can have significant impacts on wildlife. The invasive graminoids Phragmites australis (Cav.) Trin. ex Steud, hereafter Phragmites, and Typha × glauca Godr. are rapidly spreading into North American wetlands, replacing native vegetation. Invasive Phragmites is considered a potential threat to several species-at-risk (SAR), including some turtle species. My study wetland contained large stands of Phragmites, as well as Typha spp. (including invasive T. × glauca) that have similar structural traits to Phragmites. To explore the hypothesis that Phragmites and Typha spp. do not provide suitable habitat for turtles, I tested the prediction that turtles avoid Phragmites- and Typha-dominated habitats. I used VHF-GPS transmitters to follow Blanding's turtles (Emydoidea blandingii, n = 14) and spotted turtles (Clemmys guttata, n = 12). I found that both turtle species did not avoid Phragmites- or Typha-dominated habitats when choosing a home range, or while moving within their home range. I also tested whether the microhabitat selection of Blanding's turtles and spotted turtles is affected by shoot density of Phragmites, Typha spp., or both. I compared shoot densities of Phragmites and Typha spp. in 4 m2 plots, from locations used by tracked turtles with paired, random locations in these turtles' home ranges. For both turtle species, the densities of Phragmites and Typha shoots were comparable between used and random locations within the home ranges (generalized linear mixed model; p > 0.05). The use of Phragmites- and Typha-dominated habitats by Blanding's turtles and spotted turtles suggests that these habitats do not automatically constitute "unsuitable habitats" for turtles. Phragmites and Typha spp. (especially T. × glauca) can replace preferred habitats of some turtle species, and the control of these invasive macrophytes can help to preserve habitat heterogeneity. However, the presence of SAR turtles in Phragmites and Typha spp. stands should inform risk-assessments for invasive plant species control methods that include mechanical rolling of stands, where heavy machinery might encounter turtles.

Author Keywords: Blanding's turtles, compositional analysis, habitat selection, Phragmites australis, spotted turtles, Typha x glauca

The parasitic protist Giardia intestinalis possesses flavohemoglobin (gFlHb), an enzyme that detoxifies nitric oxide to the less harmful nitrate, and is a potential target for antigiardial drugs that act as ligands to the iron of its heme cofactor. In this work, the binding constants KD of gFlHb, three active-site variants (Q54L, L58A, Y30F) and the E. coli flavohemoglobin (Hmp) towards cyanide, azide and several substituted imidazoles were measured by optical titration. Certain cases such as gFlHb and Hmp were studied further by isothermal titration calorimetry. Binding constants for cyanide and the imidazoles ranged from 2 to 100 M, with the highest affinities observed with for miconazole, a bulky substituted imidazole. Azide was a poor ligand, with binding constants between 0.48 and 26 mM. Among gFlHb and its mutants, L58A tended to have the highest ligand affinities, as mutation of the distal leucine to a less bulky distal alanine residue facilitates the access of the exogenous ligand to the heme iron. In contrast, the Q54L and Y30F variants had binding affinities that in most cases were similar to wild type, which suggests that the inability of their side chains to form hydrogen bonds to these ligands is not a significant factor in binding of imidazole ligands to the enzyme. Comparative results for Hmp and gFlHb ligand binding affinities revealed slight differences which might be explained by the presence of different residues in their active sites apart from their conserved residues.

Author Keywords: Flavohemoglobin, Giardia intestinalis, Imidazole binding, Ligand binding, Nitrosative stress

Natural establishment of vegetation on mine tailings is generally limited. Understanding the processes leading to vegetation germination and the survival mechanisms that vegetation species employ in these harsh environments is critical to future remediation efforts. As metalliferous mine tailings are generally nutrient-poor, high in harmful metals, and acidic, vegetation species require distinct mechanisms to germinate and survive in such harsh environments. In this study, edaphic and biotic factors linked to vegetation establishment and diversity were studied at two nickel-copper (Ni-Cu) tailings sites near Sudbury, Ontario. One site had experienced minimal treatment, and the second site was split into partial (hand-distribution of lime) and full (lime, fertilizer, seeding) treatment areas. Tailings were generally acidic, low in organic matter and "available" nutrients, and high in metals such as Al, Cu, Fe, and Ni, but these physical and chemical properties were extremely spatially variable. At both sites, vegetation was distributed in sparse patches, with the greatest diversity in treated areas. There was no clear link between metals and vegetation establishment/diversity at the sites. The primary limiting nutrients on the tailings were phosphorous (P) and potassium (K), and while there were areas of increased soil fertility at the sites, they were not clearly associated with increased vegetation diversity. Both traditional ecological succession and nucleation succession patterns were observed on the site, and the chief species associated with nucleation were primary colonizing trees such as B. papyrifera and P. tremuloides. The relationship between B. papyrifera nutrient retranslocation and tailings restoration was assessed and while B. papyrifera at the sites were deficient in P and K, the trees efficiently retranslocated both P and K during senescence. This research can provide insight into possibilities for future revegetation of similar tailings, enabling industry to make educated decisions when choosing where and how to revegetate, mimicking natural succession patterns.

Author Keywords: Acid-mine drainage, Betula papyrifera, ecosystem health, metals, Sudbury, tailings

The "upfront" embodied carbon (EC) of building materials includes the accumulated greenhouse gas (GHG) emissions resulting from harvesting, manufacturing and transportation processes, and is becoming more widely recognized as a major source of global GHGs. The aim of this study is to demonstrate the potential for buildings to go beyond reduced or zero GHG emissions and to become– at least temporarily – a negative emissions technology, namely places of net storage of carbon. The study examines the EC for two samples of low-rise residential buildings that are representative of the North American wood-framed typology: a single-unit raised bungalow of 185m2 and an eight-unit, four-story of 935 m2. Data from Environmental Product Declarations (EPDs) for a wide variety of materials that could feasibly be used to construct the sample buildings are used to calculate the total EC for four different material assemblies in each building type: High EC, Typical EC, Best Conventional EC and Best EC. Results demonstrate the upfront embodied carbon can vary widely, ranging from a worst-case scenario of 415 kgCO2e/m2 of net emissions to a best case of 170 kgCO2e/m2 of net carbon storage by using biogenic (plant-based) materials. In addition, an energy modeling analysis of the buildings was conducted for the Toronto, Ontario climate to compare the EC with the operational carbon (OC) emissions. The results show that achievable reductions in EC could provide more than four times the overall GHG reductions than energy efficiency improvements to reduce OC between 2020 and 2050. The building model with both the lowest EC and OC is shown to have net carbon storage for several centuries. At the current scale of US residential construction, annual carbon storage in residential buildings as modeled could reach 30,000,000 tonnes, the equivalent of 10 coal-fired power plants. The immediate impact of large-scale GHG reductions from the use of carbon-storing materials is demonstrated to be worthy of consideration for the building industry and related policy makers.

Author Keywords: Biogenic carbon, Carbon accounting, Embodied carbon, Energy efficiency, Life cycle analysis, Operation emissions

This thesis utilized a unique data-set, the Quinte Longitudinal Survey, to explore relationships among precarious employment and a range of mental health problems in a representative sample of Ontario young adults. Study 1 focused on various behavioural addictions (such as problem gambling, video gaming, internet use, exercise, compulsive shopping, and sex) and precarious employment. The results showed that precariously employed men were preoccupied with gambling and sex while their female counterparts preferred shopping. Gambling and excessive shopping diminished over time while excessive sexual practices increased. Study 2 focused on the association between precarious employment and substance abuse (such as tobacco, alcohol, cannabis, hallucinogens, stimulants, and other substances). The results showed that men used cannabis more than women, and the non-precarious employed group abused alcohol more than individuals in the precarious group. This research has implications for both health care professionals and intervention program developers when working with young adults in precarious jobs.

Author Keywords: Behaviour Addictions, Precarious Employment, Substance Abuse, Young Adults

This dissertation is a critical review of the discursive formation of Islamic art in the twentieth century and the continuing problems that the early categorization of this discipline carries. It deals with the impact of these problems on the conceptualization of another category, Persian art. The subject is expounded by three propositions. First, the category of Islamic art was initially a product of Orientalism formulated regardless of the indigenous/Islamic knowledge of art. Second, during the early period when art historians examined different theoretical dimensions for constructing an aesthetic of Islamic art in the West, they imposed a temporal framework on Islamic art in which excluded the non-traditional and contemporary art of Islamic countries. Third, after the Islamic Revolution in 1979, Iranian scholars eventually imposed academic authority over the discipline of Persian/Islamic art, they adopted the same inadequate methodologies that were initially used in some of the early studies on the art of the Muslims. These propositions are elaborated by examples from twentieth-century Iranian movements in painting, The Coffeehouse Painting and The School of Saqqakhaneh, and the incident of swapping Willem de Kooning's painting Woman III with the dismembered manuscript of the Shahnama of Shah Tahmasp in 1994. The conceptualization of Islamic art as a discipline is also discussed in relation to the twentieth-century cultural context of Iran. The argument is divided into three chapters in relation to three important historical moments in the history of contemporary Iran: The Constitutional Revolution (1905-1911), the modernization of Iran (1925-1975), and the Islamic Revolution (1979-onward). The formation of the discourse of Islamic art is the fruit of nineteenth-century Orientalism. Out of this discourse, Persian art as a modern discourse addressing the visual culture of Pre-Islamic and Islamic Iran came into being. I claim that after the Islamic Revolution, Iranian academics demonstrate a theoretical loyalty to the early theorizations of Islamic/Persian art. By this token, visual signs are given a meta-signified in the narrative of Islamic art. The ontological definition of this meta-signified is subjected to the dominant ideology, which determines how different centers of meaning should come into being and disappear. In the post-Revolution academia, the center is construed as the transcendental signified. Such inherence resulted in a fallacy in the reading of the Persian side of Islamic art, to which I refer as the "signification fallacy." The dissertation draws on the consequences of this fallacy in the critique of Islamic art.

Keywords: Persian art, Islamic art, Iranian art; Persian classical literature, Narrative. Image, Representation, Aniconism, Abstraction, Modernity, Tradition, Orientalism, The Constitutional Revolution, Modernization, The Islamic Revolution. Shahnama of Shah Tahmasp, The Coffeehouse Painting, The School of Saqqakhaneh; Modernism: Woman III.

Author Keywords: Iranian Art, Islamic Art, Orientalism, Persian Art, The Constitutional Revolution, The Islamic Revolution

Populations of grassland birds, including the Bobolink (Dolichonyx oryzivorus), are experiencing steep declines due to losses of breeding habitat, land use changes, and agricultural practices. Understanding the variables affecting reproductive success can aid conservation of grassland species. I investigated 1) whether artificial nest experiments accurately estimate the impacts of cattle on the daily survival rate of Bobolink nests and 2) which local, landscape, and temporal variables affect daily survival rate of Bobolink nests in Southern Ontario. I replicated an artificial nest experiment performed in 2012 and 2015 to compare the daily survival rate of artificial and natural nests at multiple stocking rates (number of cattle × days × ha-1). I also monitored Bobolink nests and modeled daily survival rate using local variables (e.g., stocking rate, field use, patch area), landscape variables (e.g., percent forest within 2, 5, and 10 km), and temporal variables (e.g., year, date of season). Results indicate that artificial nest experiments using clay shooting targets overestimated the impacts of stocking rate on the daily survival rate of Bobolink nests. With natural nests, region (confounded by year and field use), stocking rate, and date of season were the strongest predictors of daily survival rate; with stocking rate and date of season both having a negative effect. Management should focus on conserving pastures with low stocking rates (< 40 cattle × days × ha-1), late-cut hayfields, fallow fields, and other grasslands to protect breeding grounds for the Bobolink and other declining grassland bird species.

Author Keywords: Bobolink, Daily survival rate, landscape variables, local variables, Nest survival, temporal variables