VictorJuiz/thesis huggingface dataset:
The Malleability of Music Preferences: Effects of Individual Differences and the Listening Context
Keywords: Music
Liking for Music
Emotion
Openness to Experience
Musical Development
Exposure and liking

Despite the ubiquity of music and its importance to one’s identity, there has been limited research on individual differences in music preferences. The aim of this dissertation was to examine how music preferences vary across individual differences in stable traits (e.g., gender, personality) and states (e.g., mood) over three studies. The focus of Study 1 was on the influence of the listener’s mood on emotion-based music preferences. The typical preference for happy- over sad-sounding music was found to be mood-dependent, evident after happy and neutral but not sad mood inductions. When the music was emotionally ambiguous (i.e., with cues to both happiness and sadness), happy listeners liked the music more than other listeners, whereas sad listeners perceived it to be more sad-sounding. Study 2 examined how emotion-based music preferences develop. Adults and children 5, 8, and 11 years of age listened to short pieces expressing emotions that varied in arousal and valence: happiness (high, positive), scariness (high, negative), peacefulness (low, positive), or sadness (low, negative). Adults preferred pieces with a positive valence (happy and peaceful), whereas children preferred excerpts depicting high-arousal emotions (happy and scary). Identification accuracy was predictive of a positive-valence bias among 5- and 8-year-olds. A number of other findings related to accuracy and gender differences were also evident. Study 3 examined whether personality differences affect the influence of exposure on liking. Undergraduates completed the Big Five Inventory and provided liking ratings for novel music excerpts as well as for excerpts they heard 2, 8, or 32 times. Higher scores on Openness-to-Experience were related to greater liking for novel excerpts and more rapid satiation. In sum, these three studies highlight that music preferences vary as a function of individual differences and the listening context.
Quantification of Blood Flow Using Ultrasound Contrast Agents
Keywords: Ultrasound
Blood flow
Ultrasound contrast agents
Microbubbles

Contrast enhanced ultrasound offers a unique method to measure the blood flow, perfusion, vascular volume and morphology of microvascular networks. This is achieved by exploiting the ability of microbubble contrast agents to be disrupted and preferentially detected with contrast specific imaging techniques – using a method known as disruption-replenishment. In its current form, disruption-replenishment suffers from poor reproducibility and accuracy, largely due to the inappropriate application of a mono-exponential model of microbubble replenishment, and an incomplete understanding of the dependencies of the measurement. In this thesis, we hypothesize that disruption-replenishment measurements can be improved by applying a perfusion model that considers the physical elements of the measurement, including the haemodynamics and morphology of the vascular system, the ultrasound field distribution and microbubble properties. We present a flexible, theoretical framework to model microbubble replenishment within the microvasculature. The replenishment model is further developed by in vitro and in vivo validation, and clinical translation in a trial of anti-angiogenic therapy in patients, resulting in a proposed clinical protocol. The presented formalism was shown to be more robust and demonstrated better agreement of both ﬁtting quality and estimates of flow velocity when compared to the established model (accuracy to within 3-9%). The reproducibility of repeated in vivo disruption-replenishment flow measurements was 11.9% using the proposed perfusion model compared to 24% using the established model. Variability of clinical perfusion measurements was also reduced with a method that discards the contribution of flow from larger arteries. Excluding the large vessel component in clinical measurements of tumour blood volume decreased the inter-plane variability by up to 20%. The proposed perfusion model can be used to generate parametric maps of vascularity through which additional quantitative parameters become available. These improvements will help translate the method of disruption-replenishment into routine clinical practice and clinical trials.
Essays on Human Capital, Wage Dispersion and Worker Mobility
Keywords: Earnings Dynamics
Mobility
Inequality
Human Capital

This dissertation is comprised of three papers. In Chapter 1 I analyze if career heterogeneity in terms of life-cycle earnings, occupational mobility and unemployment is predominantly driven by skills acquired prior to labor market entry or by decisions made and shocks accumulated over the working life. My study is based on a Dynamic Discrete Choice model that enriches the proto-typical dynamic Roy-model with a number of potentially important sources of career heterogeneity, such as match heterogeneity and permanent shocks to skills. I find that a large fraction of life-cycle income inequality is driven by match heterogeneity among workers with the same observable and unobservable credentials. Differences in comparative advantages, though quantitatively important as well, have a much smaller impact than what has been found in research that relies on estimates from more restrictive dynamic Roy models. In Chapter 2 I estimate a flexible non-stationary variance components model of residual earnings dynamics and investigate if recent increases in residual inequality are caused by an increase of the variances of permanent, persistent or transitory shocks. My results suggest that underlying sources of increasing wage inequality are very different across education groups. Most importantly, only the lesser educated experience a large increase in earnings instability. Chapter 1 and 2 utilize a unique administrative data set from Germany that follows workers from the time of labor market entry until twenty-three years into their careers. In the last chapter I investigate empirically if a particular set of pre-labor market skills – namely university student achievement – can be fostered by assigning male teachers to male students and female teachers to female students. I find that being taught by a same-sex instructor helps students to improve their relative grade performance and the likelihood of completing a course, but the magnitudes of these effects are small.
Analysis of Mitochondrial Signaling in the Regulation of Programmed Cell Death
Keywords: programmed cell death
mitochondria
development
acute neural injury
Bcl-2
calcineurin
caspases
inhibitor of apoptosis proteins
Smac/DIABLO
genetic modification
immunophilin ligands
neuroprotection
gamma motor neurons

The involvement of mitochondrial signaling in mammalian PCD regulation has been examined extensively via biochemical analyses and cellular studies in vitro. However there still exist considerable gaps in our knowledge regarding its contribution in specific tissues and cell types during mammalian development in vivo. In addition, given the numerous pathologic conditions associated with aberrant PCD, modulation of this signaling process represents an attractive target for therapeutic intervention. In this thesis I have therefore examined the regulation of mitochondrion-mediated PCD signaling as it pertains to several forms of developmental and injury-induced cell death. In the first component of the thesis I have examined the differential sensitivity of Bcl2 on the survival of motor neuron populations from two distinct developmental origins (alpha and gamma motor neurons), demonstrating that gamma motor neurons are preferentially affected in Bcl2 null mice. Thus, Bcl-2 plays a critical in vivo in regulating subtype-specific motor neuron survival during development. In the second study I have demonstrated that a major portion of the neuroprotective effect exerted by the immunophilins cyclosporin A and FK-506 are mediated through calcineurin signaling; rather than MOMP-mediated events as previously held. Additional findings of this study demonstrated the first neuroprotective effects of the pyrethroid insecticide cypermethrin and calcineurin-mediated control of Bad phosphorylation. Such findings establish a link between calcineurin signaling and mitochondrion-mediated cell survival. The above studies established critical features of mitochondrion-mediated PCD in regulating survival of several neuronal subpopulations. I therefore followed these studies with an examination of how post-mitochondrial PCD signaling is regulated following MOMP permeabilization. Specifically I examined regulation of the Smac-IAP-caspase axis, investigating how combinatorial deletion of Casp3 and Diablo alter PCD progression in mouse embryonic fibroblasts. Using a series of injury stimuli in the context of biochemical and cellular analyses I have developed a model of how endogenous Smac/DIABLO regulates executioner caspase activity. Collectively these studies elucidate key aspects of mitochondrial signaling during both developmental and injury-induced PCD in vivo.
The Ethics of Simplicity: Modernist Minimalism in Hemingway and Cather
Keywords: American Literature
Narrative Theory
Ernest Hemingway
Willa Cather
Ethics
Simplicity

This study investigates how minimalist narrative techniques in American modernist literature oblige us, as readers and critics, to be self-reflexive about the ethical basis of interpretation. Through a concentrated narratological analysis of Hemingway’s and Cather’s fiction, I identify three major elements of what I term the “simple text”—thinness, smoothness, and spaciousness—and I show how each category engages a hermeneutic ethics. By gesturing towards accessibility and straightforward comprehension while also producing moments of indeterminacy that subtly resist the reader’s inferences, the simple text challenges the reader to conceive interpretation both as a positive exercise of individuation and imagination and, simultaneously, as a potentially unethical mode of critical violation and imposition. My introduction contemplates the ethical foundations of Hemingway’s and Cather’s famous aesthetics of omission to argue that such simplicity conveys a complex theory of reader engagement. Chapter One defines “thinness” by examining “thin characters” in A Farewell to Arms and My Ántonia—characters whose simplicity makes them paradoxically unreadable in a way that foregrounds the nature of our accountability towards others. The second chapter, focusing on In Our Time and Death Comes for the Archbishop, defines “smoothness” as a simple paratactic patterning that challenges our critical desire to generalize meanings from particular experiences. While the smooth surface invites our interpretive touch, its structural integrity resists marking and inscription. The final chapter details the element of “spaciousness,” showing how open and simple settings in The Old Man and the Sea and The Professor’s House inspire, in the protagonists, moments of self-conscious interpretation of the nonhuman other and solicit a practice of accountable freedom. I argue that the foregrounding of such spaces proffers a subtle yet pointed critique of American individualism, but this critique is learned only through our encounter with the text’s interpretive limits. The study concludes by suggesting how these strategies both respond to and participate in specific criticisms of American democracy that circulated during the modernist period.
Ironic Acceptance – Present in Academia Discarded as Oriental: The Case of Iranian Female Graduate Student in Canadian Academia
Keywords: Middle Eastern women
First generation Iranian immigrant
Racialized female graduate students
Androcentric Canadian higher education
Neo-liberalism and Canadian higher education
Orientalism
Racism
stereotyping
adaptation
discrimination
marginalization
belonging
being silenced
Iranian immigrant educated women in Canadian graduate school
9/11 and Oriental women in Canadian school
Oppression
Muslim women

The purpose of this research is to examine the experiences of first-generation, highly educated Iranian women who came to Canada to pursue further education in a ‘just’, ‘safe’, and ‘peaceful’ place. The research has revealed that these women who were fleeing from an ‘oppressive’ and ‘unjust’ Iranian regime face new challenges and different forms of oppression in Canada. This dissertation examines some of the challenges that these women face at their place of work and/or at graduate school. The research findings are based on narratives of eleven Iranian women who participated in in-depth interviews in the summer of 2008. These women, whose ages range from 26 to 55 and are of diverse marital status, all hold an academic degree from Iran. They were also all enrolled in different graduate schools and diverse disciplines in Ontario universities at the time of the interviews. The research findings indicate that their presence in Canada became more controversial after the September 11, 2001 attack on the World Trade centers in New York. Historically, the social images imposed on Middle Eastern women derive from the Orientalism that arose following the colonization of the Middle East by Western imperialists. The perpetuation of such images after the 9/11 attack has created a harsh environment for the participants in this research. After 9/11 most immigrants from the Middle East were assumed to be Muslim and Arab, which many North Americans came to equate with being a terrorist. In order to analyze the participants’ voices and experiences, I have adopted a multi-critical theoretical perspective that includes Orientalism, anti-colonialism and integrative anti-racist feminist perspectives, so as to be equipped with the tools necessary to investigate and expose the roots of racism, oppression and discrimination of these marginalized voices. The findings of this research fall under six interrelated themes: adaptation, stereotyping, discrimination, being silenced, strategy of resistance, and belonging to Canadian society/ graduate school. One of the important results of this research is that, regardless of the suffering and pain that the participants feel in Canadian graduate school and society, they prefer to stay in Canada because of the socio-political climate in Iran.
Impact of CYP2A6 Genetic Variation on Nicotine Metabolism and Smoking Behaviours in Light Smoking Populations of Black-African Descent
Keywords: Pharmacogenetics
Nicotine
CYP2A6

Populations of Black-African descent have slower rates of nicotine and cotinine metabolism, smoke fewer cigarettes (~10 cigarettes/day), and have higher incidences of tobacco-related illnesses compared to Caucasians. Cytochrome P450 2A6 (CYP2A6) is the main enzyme involved in the metabolism of nicotine and its proximal metabolite cotinine, as well as tobacco-specific nitrosamines. Genetic polymorphisms in CYP2A6 contribute to the large variability observed in rates of nicotine metabolism. Reduced CYP2A6 activity has been associated with fewer cigarettes smoked, higher quit rates, and lower lung cancer risk in predominantly moderate to heavy-smoking (~20–30 cigarettes/day) Caucasians. CYP2A6 genetic variants and their impact on smoking behaviours have not been well studied among individuals of Black-African descent. The main objectives herein were to identify and characterize new CYP2A6 variants that may explain the slower rates of metabolism, and determine whether CYP2A6 variation is a predictor of smoking phenotypes in this population. Furthermore, we examined whether previously validated biomarkers of tobacco exposure have limitations among individuals of Black-African descent given their low and sporadic smoking patterns. A new CYP2A6 variant (CYP2A6*23) was found in individuals of Black-African descent recruited for a nicotine pharmacogenetic-pharmacokinetic study. CYP2A6*23 reduced activity towards nicotine and coumarin in vitro and was associated with slower rates of CYP2A6 kinetics in vivo. In a clinical trial of African-American light smokers, CYP2A6 slow metabolizers were more successful at smoking cessation compared to normal metabolizers, although no differences in cigarette consumption were found. Two common biochemical markers of tobacco smoke exposure, cotinine and exhaled carbon monoxide, were weakly correlated with self-reported cigarette consumption. These biomarkers were not substantially affected by variables previously shown to alter amount smoked and/or rates of cotinine metabolism such as gender, age, body mass index or smoking menthol cigarettes. However, CYP2A6 slow metabolizers had significantly higher cotinine without smoking more cigarettes. Identification and characterization of novel variants adds to our understanding of nicotine pharmacokinetic differences between racial/ethnic minority groups and improves accuracy of CYP2A6 genotype groupings for genetic association studies. Furthermore, better insight into the biological factors associated with smoking behaviours will aid in the development of more efficacious targeted treatments for this understudied population.
Molecular Barcoded Plasmid Yeast ORF Library: Linking Bioactive Compounds to their Cellular Targets and Mapping Dosage Suppressor Networks
Keywords: Budding yeast
Functional genomic

In this thesis I describe a functional genomics resource in which each yeast gene, with its native promoter and 3’UTR, is cloned on a uniquely barcoded low-copy vector. We refer to this resource as the Molecular Barcoded Yeast ORF (MoBY-ORF) library 1.0. Each gene carried by MoBY-ORF 1.0 should mimic its native expression and thus is best suited for complementation cloning. The vector backbone of MoBY-ORF 1.0 is compatible with the mating-assisted genetically integrated cloning (MAGIC) system for recombination cloning in bacterial cells, which allows the transfer of the ORF fragment and its barcoded cassette to other vector backbones. Taking advantage of the MAGIC system, we created a multi-copy version of the library, which we refer to as MoBY-ORF 2.0. I used MoBY-ORF 1.0 to map drug resistant mutants by complementation cloning with a barcode microarray readout. I investigated several drugs with known targets in my proof-of-principle experiments and showed the feasibility of this method. I identified a single mutation that causes resistance to two different natural products, theopalauamide and stichloroside. By doing so, I was able to link these two chemicals to their cellular target, ergosterol. In fact, theopalauamide represents a new class of sterol binding chemical. I also describe the use of MoBY-ORF 2.0 to clone dosage suppressors of conditional temperature-sensitive mutants. By doing so, and combing our own data with published literature, we showed that dosage suppression interactions often overlap with protein-protein interactions and negative genetic interactions but not positive interactions; however the majority of dosage suppression interactions are unique and thus they represent an unique edge on a global functional interaction map. We also describe the first genome-wide dosage suppressor interaction map of budding yeast.
Subfilter Scale Modelling for Large Eddy Simulation of Lean Hydrogen-enriched Turbulent Premixed Combustion
Keywords: Combustion
Large Eddy Simulation
Computational Fluid Dynamics
Subfilter Scale Modelling

Hydrogen (H2) enrichment of hydrocarbon fuels in lean premixed systems is desirable since it can lead to a progressive reduction in greenhouse-gas emissions, while paving the way towards pure hydrogen combustion. In recent decades, large-eddy simulation (LES) has emerged as a promising tool to computationally describe and represent turbulent combustion processes. However, a considerable complication of LES for turbulent premixed combustion is that chemical reactions occur in a thin reacting layer at small scales which cannot be entirely resolved on computational grids and need to be modelled. In this thesis, subfilter-scale (SFS) modelling for LES of lean H2-enriched methane-air turbulent premixed combustion was investigated. Two- and three-dimensional fully-compressible LES solvers for a thermally perfect reactive mixture of gases were developed and systematically validated. Two modelling strategies for the chemistry-turbulence interaction were pursued: the artificially thickened flame model with a power-law SFS wrinkling approach and the presumed conditional moment (PCM) coupled with the flame prolongation of intrinsic low-dimensional manifold (FPI) chemistry tabulation technique. Freely propagating and Bunsen-type flames corresponding to stoichiometric and lean premixed mixtures were considered. Validation of the LES solvers was carried out by comparing predicted solutions with experimental data and other published numerical results. Head-to-head comparisons of different SFS approaches, including a transported flame surface density (FSD) model, allowed to identify weaknesses and strengths of the various models. Based on the predictive capabilities of the models examined, the PCM-FPI model was selected for the study of hydrogen-enrichment of methane. A new progress of reaction variable was proposed to account for NO. The importance of transporting species with different diffusion coefficients was demonstrated, in particular for H2. The proposed approach was applied to a Bunsen-type configuration, reproducing key features observed in the experiments: the enriched flame was shorter, which is attributed to a faster consumption of the blended fuel; and the enriched flame displayed a broader two-dimensional curvature probability density function. Furthermore, reduced levels of carbon dioxide (CO2), increased levels of nitrogen monoxide (NO), and a slight increase in the carbon monoxide (CO) levels in areas of fully burned gas were predicted for the enriched flame.
Interference Control in Memory and Fluid Intelligence
Keywords: memory
Interference
aging
intelegence

This thesis investigated the role of interference in general cognitive functioning. Study 1 explored the relationships among interference control, memory, and fluid intelligence. Studies 2 and 3 explored the possibility that interference is controlled by suppressing the interfering information rather than, for example, facilitating the target information. Study 1 tested the hypothesis that individual differences in the ability to regulate interference are responsible for the correlation between memory tasks and fluid intelligence. Participants completed common measures of working memory, long-term memory, fluid intelligence, and interference regulation. In structural equation models, controlling for interference regulation ability largely accounted for the correlation between the memory tasks and fluid intelligence. These results suggest that efficient interference control is critical to cognitive functioning. Study 2a tested the hypothesis that interference is regulated by suppressing competing responses. In Phase 1 of a three-phase paradigm, participants performed a vowel-counting task that included pairs of orthographically similar words (e.g., allergy/analogy). In Phase 2 participants solved word fragments (e.g., a _ l _ _ gy) that resembled both words in an earlier pair, but could be completed only by one of these words. Phase 3 measured the consequence of having resolved interference in Phase 2 by asking participants to read a list of words, including the rejected competitors, as quickly as possible. Relative to participants in control conditions that did not require interference resolution these interference condition participants were slower to name competitor words. Study 2b showed that while competitors are suppressed during interference resolution, a complementary facilitative process does not directly enhance accessibility of targets. Finally, Study 3 tested the hypothesis that older adults have impaired suppression abilities. Older adults were tested in the same paradigm used in Studies 2a and 2b. In contrast to younger adults, older adults showed no suppression of competitors. This result supports the theory that some age related memory deficits stem from impaired suppression processes.