VictorJuiz/thesis huggingface dataset:
Projecting the Influence of Climate Change on Extreme Ground-level Ozone Events in Selected Ontario Cities

Ground-level ozone (O3) is perhaps one of the most familiar pollutants in Ontario, Canada because it is associated with most smog alerts in the province. O3 varies on a number of spatial and temporal scales, primarily due to meteorological variability and the impact of long-range transport of its precursors on the photochemical processes. The goal of this thesis is to project the change in the probability of occurrence of future Extreme Ground-level Ozone Events (EGLOEs) due to changes in atmospheric conditions as a result of climate change for cities located in the southern, eastern and northern parts of Ontario, Canada by using a combination of General Circulation / Global Climate Models (GCMs) and statistical downscaling. These Ontario cities are Toronto, Windsor, London, Kingston, Ottawa, Thunder Bay, Sudbury and North Bay. The successful downscaling method used in this research to generate city-specific climate change scenarios was the Statistical DownScaling Model (SDSM) version 4.2.2, which is a hybrid of regression-based and stochastic weather-generator downscaling methods. The results indicate that the mean values of the daily maximum ground-level ozone concentrations could increase by up to 12 – 17% in Southern Ontario, 8 – 16% in Eastern Ontario and 1.5 – 9% in Northern Ontario by the end of the century due largely to changes in long-range transport. Three important themes emerge from the results: 1) the research successfully model O3 concentration in a region where long-range transport plays a substantial role. 2) The clear confirmation regarding the role of long-range transport in determining O3 concentration in most areas of Ontario. 3) The projected increase of ozone in Ontario, due largely to an increase of long-range transport, caused by shifting atmospheric dynamics rather than a direct temperature effect on ozone production. Moreover, the results indicate that the future Southern, Eastern and Northern Ontario’s EGLOEs with the O3 concentration ≥ 80 ppb (the current Ontario 1-hour Ambient Air Quality criterion for extreme ozone concentration) will have an increase of over 60%, 50% and 62% respectively by the year of 2100 under the different future scenarios in the third version of the Coupled Global Climate Model (CGCM3) and the Hadley Centre’s Climate Model (HadCM3).

Keywords: Canada
Climate change
Extreme tropospheric ozone
Ontario
Statistical downscaling
Urban smog
Advisor: Gough, Williams A
Story of Brominated Flame Retardants: Substance Flow Analysis of PBDEs from Use to Waste

The main goal of this study was to understand the fate of brominated flame retardants (BFRs), particularly PBDEs, during the life cycle of BFR-containing products. PBDEs were added to the Stockholm Convention list of chemicals to be eliminated. The migration of BFRs from products and their partitioning to dust results in human exposure through dust ingestion and inhalation. Moreover, during the use of BFR-containing products, direct contact with these products can lead to human exposure. With the proliferation of BFRs as PBDE alternatives, identifying the product source of these chemicals is essential to minimize the risk associated with the exposure. In this research, a rapid and non-destructive method was developed to identify and to some extent quantify BFRs used in consumer products. The next step towards the management of these chemicals is to estimate the time course by which these chemicals will remain in use. Based on consumption patterns of PBDE-containing products, the time-dependent stock of PBDEs contained in in-use products was estimated for the U.S. and Canada from 1970 to 2020. Considering only the first lifespan of products, the stock of PBDEs was estimated to be ~120,000 t in 2014 and it is estimated that by 2020, ~ 60% of this stock will remain in products in the use phase. Although the flow of PBDE-containing products to the waste phase started to decline following 2008, this flow will continue as these products reach their end of life and enter the waste phase. As these products leave the first use phase, their accumulation in storage and waste phases will continue to act as sources of PBDEs to the surrounding environment with annual emission rate of 0.3-4 tonnes路y-1 between 1970 and 2020. Thus, the management of BFR-containing products deserves more attention as the mismanagement of these products, especially waste electronics, has led to undesirable and irreversible global environmental consequences. The results of this dissertation suggest that current waste management programs in the U.S. and Canada are challenged to deal with influx of e-waste in the near future.

Keywords: Flame retardants
PBDEs
products
Substance flow analysis
Use phase
Waste phase
Advisor: Diamond, Miriam L
Towards the Development of Techniques to Facilitate the Assembly and Characterization of Quantum Dot— Gold Nanoparticle Complexes for Resonance Energy Transfer Based Assays

Resonance energy transfer between quantum dots and gold nanoparticles represents one of the most popular transduction schemes for biosensors using multi-nanoparticle complexes. This thesis investigates the influence of quantum dot positioning, relative to the gold nanoparticle, on the analytical performance of these assays. Stoichiometric assembly of the quantum dot-gold nanoparticle complexes required accurate knowledge of the quantum dot concentration. A technique was developed to quantify the molar concentration of nanoparticles in solution. This technique relied on the quantitative analysis of the statistical distribution of nanoparticle-ligand conjugates that form when nanoparticles are functionalized with small equivalents of ligand. The technique was successfully validated using gold nanoparticles, and was subsequently applied to determine the concentration of the alloy quantum dots. The precise positioning of the quantum dots relative to the gold nanoparticles required monovalent conjugates of the quantum dots. These were prepared using a magnetic bead based technique where positively charged magnetic beads were used to capture and selectively isolate the monovalent quantum dot-DNA conjugates. Successful isolation of monovalent conjugates was confirmed using single molecule fluorescence spectroscopy and the monovalent conjugates were found to retain their activity as determined using quantitative hybridization assays. Optimizing the quantum dot-gold nanoparticle assay required the investigation of two different configurations of nanoparticle arrangement. The first involved arranging quantum dots around a gold nanoparticle core, while the second involved arranging gold nanoparticles around a quantum dot core. The first configuration was found to have optimal analytical performance, as evaluated using quenching efficiencies and influence of inner filter effect. The ability to arrange multiple quantum dots around a single large gold nanoparticle minimized the negative influence of the inner filter effect, while the high quenching efficiency ensured high responses to target hybridization.

Keywords: DNA
Energy transfer
Gold nanoparticle
Monovalent conjugates
Nanoparticle quantification
Quantum dot
Advisor: Krull, Ulrich J
Fluctuation Analysis of Oxidation-Reduction Potential in Circumneutral pH Iron-Oxidizing Microbial Systems

The goal of this thesis was to assess the utility of using small-scale fluctuations in oxidation-reduction (redox) potential to distinguish microbial from chemical iron oxidation. Fluctuations in potential arise from the motion of particles in a fluid; measuring fluctuations is therefore a system-scale observable property of micro-scale chemical behaviour, as such particle motion constitutes diffusion. Fluctuations are described by the strength of their correlation, as measured by scaling exponents. A method for the calculation of scaling-exponents of long-range correlation in redox potential measurements was developed, including new instrumentation and the modification of an existing physiological processing algorithm for use with environmental microbiological data sets. Steady-state biological and chemical systems were compared, and scaling exponents calculated from each system were found to differ significantly. In a final study, a series of microcosms were used to determine the relationship between scaling exponent, measuring correlation strength, and oxidation rate. The biological systems are governed by the rate of reaction, while the chemical systems appear to be diffusion-controlled. Because in these systems, Fe(II) is a metabolite, redox potential can then be interpreted as a physically-constrained proxy for metabolic activity. This allows the characterization of biological activity in situ.

Keywords: biosignature
detrended fluctuation analysis
iron-oxidizing bacteria
oxidation-reduction potential
Advisor: Ferris, F Grant
Dis-placing the Prison: Carceral Space, Disposable Life, and Urban Struggle in Neoliberal America

This dissertation contributes to the emerging field of carceral geography by demonstrating how carceral space produces and manages social disposability in late capitalist American life. In so doing, it posits that carceral space must be conceived as a complex geography, one that inscribes the production of racialized poverty, incarceration, and devalued life into its everyday socio-spatial relations. Carceral space encompasses the whole chain of relationships that make up the prison system: from the sites of criminalization, arrest and conviction to the landscapes of building construction; from edifices of captivity to the spaces deployed for the circulation and transfer of bodies. Carceral space also, I argue constitutes those social relations and geographic practices through which the stateâ s capacities of containment, displacement and dispossession are put to work for racial capitalism. The dissertation examines several illustrative carceral spaces at different points along the continuum of penal coercion in order to answer the question: How does carceral space help produce and manage social disposability? Using qualitative methods, including in-depth interviews, ethnographic participant observation, and textual analysis, my four case studies demonstrate that the production of disposability is an active process, spatialized in a range of places and forms that are politically mutable, highly contested, and differentially experienced. Throughout my case studies, geographies of spatial isolation and individuation function alongside the neoliberal logic of individual responsibility, to undermine black sociality and the forging of collective counter-power to racial capitalism and the carceral state. I argue that the racialized production of the â criminalâ provides powerful legitimizing cover for the making and social differentiation of surplus populations. The criminal is a paradigmatic category of disposability in capitalist liberal democracies precisely because the project of neoliberalism makes it so hard to divest from the economy of individualized responsibility and accountability. Finally, the dissertation points to some of the ways in which the capacities of the carceral state are being retrofitted for the current political-economic conjuncture, producing new spatial fixes for managing surplus life under the pretext of penal reform. I conclude that so long as the actual social relations for which the carceral state is put to work remain unchallenged, the spatial organization of racialized unfreedom and surplus life remain a pressing and pernicious threat.

Keywords: carceral state
geography
neoliberalism
prison
surplus life
urban
Advisor: Cowen, Deborah
Maternal Depression in Barbados: Exploring How Black Women Experience, Understand, Manage and Cope with Self-Reported 'Baby Blues' and Postpartum Depression

Postpartum depression is a major depressive disorder whose onset can appear up to one year after delivery and last for weeks, months or years (O'Hara, 1987). The `baby blues' is a mild affective syndrome common during the first three days after birth and can last up to 10 days (O'Hara, 1987; Cole, 2009). Existing research on maternal depression in the English-speaking Caribbean uses epidemiological methods to investigate the incidence and prevalence of depression occurring during pregnancy and the postpartum period, but largely excludes research on the `baby blues'. Also absent from the Caribbean research are studies that use qualitative methods which can help build understanding about how women's social worlds impact their mental health (Amankwaa, 2003; Almond, 2009). To investigate these gaps, a qualitative research project was conducted with 11 (n=11) Black women in Barbados to explore how they have understood, managed, coped, and sought treatment for self-reported postpartum depression and the `baby blues'. Black Feminist and Caribbean Feminist Theoretical frameworks anchored the project and helped consider how women's social, historical, racial, and cultural backgrounds were linked to their maternal mental health. The project's findings show that early maternal depression literature from North America and Europe largely excluded women from diverse racial and cultural backgrounds. Studies conducted to fill this gap have recorded higher rates for the `baby blues' and postpartum depression in Caribbean contexts. Research with Black Caribbean women in the Diaspora highlights their Intersectional experiences and explanatory models which have helped them understand maternal depression. Barriers that prevented research participants from receiving the maternal mental health care they needed included a lack of formal information and education on maternal depression at the postnatal stage; proliferation of international and non-local information sources on maternal depression; women's intersecting race, class and gendered experiences with self-reported maternal depression; and social/cultural stigmas around mental health. The formal and informal supportive resources women discussed and critiqued during their maternal depression experiences included local healthcare institutions, family members, intimate partners, and religious and spiritual sources. The research findings confirm that maternal depression exists in Barbados, and affirms that these conditions are a global public health concern. They also show that an Intersectional framework can facilitate analyses that acknowledge women's multi-layered identities which can help transform how maternal depression is treated and prevented.

Keywords: Baby Blues
Barbados
Caribbean
Intersectionality
Maternal Depression
Postpartum Depression
Advisor: Muntaner, Carles
Defining, Investigating and Supporting Anticipatory Driving - A Systematic Investigation of the Competence to Predict Traffic

Driving research shows safety and economic benefits of anticipatory competence. While the literature recognizes the notion of anticipation, it has not yet operationalized the construct. This dissertation addresses this gap by presenting a systematic investigation of anticipation in driving. It starts by defining anticipation as a competence relying on the conscious perception of visual cues and their cognitive processing. Two driving simulator studies then investigate the ability of novice and experienced drivers to anticipate conflicts in stereotypical scenarios. The first experiment shows the feasibility of identifying anticipation through the surrogate measure of pre-event actions relative to a conflict event, and confirms the hypothesis that experienced drivers exhibit these actions more often. This experiment supports an information-processing model of anticipation. The model suggests two crucial steps for the facilitation of anticipatory competence: (1) the conscious perception of appropriate cues that serve as indicators for the traffic scenario, and (2) efficient cognitive processing of those cues for a correct situational assessment. The second experiment investigates the effect of two interfaces designed to aid these steps. The attentional interface aids only the perception of cues and is hypothesized to yield larger benefits for experienced drivers who do not struggle with the interpretation of traffic. The interpretational interface supports both steps and is hypothesized to improve particularly novice driversâ competence in interpreting traffic. Contrary to these hypotheses, results show similar improvements in anticipation for both interfaces across all participants, although fewer and shorter glances towards the attentional interface suggest that it is preferable from the perspective of driver distraction. This dissertation extends the formerly vague concept of anticipation by defining and operationalizing it as a construct, identifying anticipatory actions, demonstrating that driver experience predicts anticipatory competence, and suggesting aids to support anticipation. These advances promote anticipation as a viable construct for future driver behaviour research.

Keywords: Anticipation
Driver Behaviour
Driver Experience
Driving Simulator
In-Vehicle Displays
Novice Drivers
Advisor: Donmez, Birsen
Jamieson, Greg A.
Gender-Pay Inequality and Organizational Culture: A Multi-Organizational Analysis

According to sociologists, more female-concentrated occupations pay less mainly because societal culture devalues work associated with women. But less clear is how much the cultural context of the work organization fosters or suppresses this devaluation. This question is vital because pay and work are not formally linked at the occupation level, but at job level - through a formal workplace practice known as job evaluation. And as researchers often note, the outcomes of this practice are ultimately influenced by organizational culture. Drawing from the literature on gendered organizations, organizational culture, job evaluation, and stereotyping theory, this dissertation examines whether organizations with more masculine cultures have intensified levels of devaluation in their job-reward systems - reflecting the logic that more masculine cultures prescribe wider status differences between what is stereotyped as masculine and feminine. The analysis draws from a confidential dataset linking over 50 thousand jobs to 68 separate government organizations of a single country. Main findings suggest that while the statistical effect of organizational culture is modest, the amount of devaluation in an organization's job-reward system intensifies in more female-concentrated jobs that are located in more masculine organizational cultures. Further, in some instances, the traditional framework of job evaluation might encourage gender stereotypes to manifest as pay inequalities that benefit more female-concentrated jobs. But this counterintuitive form of inequality is largely masked in more masculine organizational cultures. Collectively, this dissertation contributes to a more organizational-cultural understanding of pay determination by considering how the cultural context of work organizations influences formal organizational activities that were intended to be gender neutral. It also contributes to the more recent gendered-organizations literature that has become increasingly concerned with the impact of organizational context on gender inequalities, and to some of the more recent social-psychological literature concerned with the impact of background effects on stereotyping outcomes.

Keywords: gender
job evaluation
organizational behavior
pay inequality
stereotyping
work
Advisor: Kervin, John
Examination of type I IFN mediated regulation of the post-transcriptional antiviral response

Interferons (IFNs) are pleiotropic cytokines that regulate both innate and adaptive immunity. Early post viral infection, there is induction and secretion of IFN-β which alerts nearby cells and primes leukocytes for an immune response. A rapid response is necessary for effective control of virus replication and spread. Previously in our lab, the IFN-α/β inducible PI-3'K/mTOR mediated induction of translation was shown to operate in concert with the prototypical JAK/STAT mediated transcription of IFN stimulated genes (ISGs). In the absence of key signaling intermediates of the PI-3'K/mTOR pathway, namely, Akt or PI-3'K, an IFN-α/β inducible antiviral response was abolished. Given the apparent importance of this pathway, we sought to enhance IFN-α/β signaling by targeting key negative regulatory intermediates. In vitro experiments demonstrated that cells lacking suppressors of translation, TSC2 or 4E-BP1, are more sensitive to IFN-α/β inducible effects as indicated by increased antiviral protein synthesis, and enhanced resistance to virus infection. In vivo experiments showed that mice lacking 4E-BP1 are similarly more resistant to virus infection, and also more sensitive to the antiviral effects of IFN-β treatment. These in vitro and in vivo effects were demonstrated for different viruses, including Vaccinia virus, Influenza virus and Coxsackievirus. Given these findings of rapid mRNA translation to enable a robust IFN antiviral response, and aware that this is an ATP consuming process, we next examined whether IFN-α/β treatment also exerted effects on cell metabolism. Through a series of in vitro experiments we demonstrated rapid IFN-α/β-mediated regulation of glucose uptake in an Akt and PI-3'K dependent manner. Given the number of signaling intermediates shared by IFN-α/β and insulin, we examined the in vivo effects of metformin, an insulin sensitizer, during antiviral treatment with IFN-β. Interestingly, prophylactic treatment with both metformin and IFN-β produced a significant antiviral effect during the acute phase of viral myocarditis caused by Coxsackievirus B3 infection. Taken altogether, the work described in this thesis provides further evidence for the importance of post-transcriptional regulation exerted by IFN-α/β during a virus infection.

Keywords: antiviral
innate immune response
interferon
metabolism
translation
virus
Advisor: Fish, Eleanor N