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Ethical Pluralism and Public Office: The Ethics of Political and Administrative Officials in Liberal Democracies
Get PDFWhat does it mean for public officials to make decisions in an ethical manner? By what meansdo public officials internalize the ethos that enables them to do so? To answer these questions,
this dissertation employs a mix of normative theory, empirical case studies, and engagement
with contemporary democratic theory to develop a theory of the ethics of public officials. I
argue that in order for public officials to make decisions in an ethical manner, they must make
decisions like ethical pluralists. This means that when making decisions, public officials must
first consider all of the relevant plural and conflicting duties of their office. After defending
ethical pluralism in the first chapter and illustrating its utility for assessing the conduct of public
officials in the second, I then turn to how public officials internalize this ethos. In the third
chapter, I develop a neo-Smithian theory of ethical socialization to explain the process by which
actors internalize an ethos such as ethical pluralism. In the following chapter, I articulate the
institutional implications of neo-Smithian ethics which include the importance of vocationalism,
progress through ranks, and professional self-regulation for the socialization of public officials.
The dissertation makes five primary contributions to the study of public officials and liberal
democracy. First, it links the ethics of administrative and political officials in a way that is novel,
arguing that all public offices are rooted in plural and conflicting liberal democratic values and
hence necessitate that public officials make decisions like ethical pluralists. Second, it connects
the micro level of individual behavior of public officials to the macro level of the health and
stability of liberal democracies. Third, the project articulates a novel explanation for why public
officials require the internalization of professional morality. Fourth, it develops a theory of neo-
Smithian ethics that I use to rectify deficiencies in existing treatments of the ethics of public
officials. Fifth, and finally, the project illustrates the significant role that public officials play in
responding to contemporary challenges from populists and authoritarians simply by making
decisions like pluralists about their positive duties of office.Ph.D
Micro-Layered Solid and Porous Alternating Structures
Get PDFMicro-/nano-layered (MNL) solid/porous alternating structures represent a promising class of multifunctional materials capable of addressing the growing global demand for scalable, lightweight, and efficient thermal management solutions. Inspired by natural architectures such as butterfly wings, these materials combine hierarchical layer design with confined polymer foaming to achieve synergistic enhancements in thermal insulation, mechanical robustness, and passive radiative cooling (PDRC) performance. Despite significant progress in MNL fabrication and characterization, the fundamental understanding of how geometric confinement, interfacial mechanics, and transient processing conditions collectively govern cell morphology evolution and material properties remain incomplete.This thesis systematically investigates the processing–structure–property relationships of MNL solid/porous systems, with a particular emphasis on confined foaming mechanisms, toughening behavior, and structure-driven thermal management performance. A combination of MNL coextrusion, compression molding, and CO₂-based batch foaming was employed to fabricate well-controlled Polycarbonate (PC)/ Polymethyl methacrylate (PMMA) layered structures with tunable geometries. Through bulk-scale foaming studies, we reveal how solid-layer confinement suppresses cell coalescence, enhances nucleation density, and induces anisotropic expansion, enabling the creation of lightweight materials with high mechanical strength, ultralow thermal conductivity, and strong solar reflectance. Leveraging these insights, we developed a bio-inspired PDRC material that achieved a 17.7°C temperature reduction under real-world conditions.
To deepen mechanistic understanding, an in situ foaming visualization platform was established, providing direct, real-time observation of cell nucleation and growth within MNL structures. These experiments revealed the existence of a strong confinement zone within 10 µm of the solid–porous interface, validating the critical role of geometric constraints in regulating foaming dynamics and enabling the fabrication of bio-mimic structures that surpass the thermal performance of butterfly wings.
Finally, the toughening mechanisms of MNL systems were explored through in situ micro-tensile testing under polarized optical microscopy. A nacre-inspired interfacial slipping mechanism was identified as a key contributor to enhanced ductility and energy dissipation, independent of crystallization or crazing suppression.
Together, these findings provide new scientific insights into confined foaming and interfacial mechanics in MNL materials, laying the groundwork for the rational design of multifunctional polymer systems for next-generation thermal management and structural applications.Ph.D
Studies of Cell Fate Specification and Reprogramming in the Nervous System
Get PDFIn the nervous system, cellular diversity is generated through progenitor cells that contain varying levels of potential for differentiating into mature neural cell types. The degree of cell fate potential is dictated through a combination of cell-intrinsic gene regulatory programs and cell-extrinsic signaling factors in the niche. Once a cell is differentiated, it must also maintain this mature state to enable tissue function. A mechanistic understanding of cell fate specification and maintenance is important for regenerative medicine efforts to replace lost or damaged cells in the nervous system and to diseases that may arise due to an improper maintenance of cell identity. In this thesis, I use two different model systems to explore these features of developmental neurobiology: the cell fate specification of photoreceptors in the mammalian retina and direct reprogramming of neurons from cells in the skin. In the retina, progenitor cells can be multipotential or more restricted in the types of cells they can differentiate into. I questioned to what extent factors in the progenitor niche restrict retinal progenitors to differentiate into photoreceptors. These experiments show, for the first time, that unique combinations of retina niche factors cause individual retinal progenitors to adopt a photoreceptor-restricted fate. Taurine and retinoic acid exposure creates clones composed of only rod photoreceptors and COCO exposure creates clones of only cone photoreceptors. Furthermore, retinal progenitors maintain competence for this photoreceptor restriction throughout every embryonic developmental stage. I also identify a novel retinal transcription factor, Sox15, that acts downstream of COCO to facilitate cone-restricted differentiation. Functional studies suggest that Sox15 works to promote cone differentiation through inhibiting differentiation towards rod photoreceptors. Direct reprogramming involves conversion of one fully differentiated cell type into another through manipulation of transcriptional programs. This contests traditional developmental models where cell fate restriction is a unidirectional process. I use the example of directly reprogramming fibroblasts from the skin into neurons to challenge the extent to which mature cells can destabilize and alter their identity. My experiments reveal that a previously unrecognized neural crest progenitor cell in the skin is the primary source of neurons in this model. This calls into question the original interpretation that a cell from a different embryonic germ layer is switching its identity to a neuron without passing through a developmentally immature state. Neural crest progenitors from the skin are developmentally derived from the brain and have an intrinsic bias to differentiate into neurons. Therefore, this is really directed differentiation of an immature precursor cell and the barriers a fully differentiated cell must overcome to reprogram are greater than previously anticipated.Ph.D
Taphonomy, Depositional Environments, and Biotic Comparisons of the Silurian Eramosa Lagerstätte, Ontario, Canada
No full textThe Silurian Period represents the first major terrestrial colonization by multicellular life, and evidence of this transition is preserved in shallow-marine environments. Comprehensive analyses of biodiversity in the fossil record are dependent on the preservation of soft-bodied taxa in Konservat-Lagerstätten, as the fossil record is biased towards preservation of mineralizedremains. The Silurian Eramosa Formation of Ontario, Canada (Wenlock Series, Sheinwoodian Stage; 432.9-430.6 Mya) preserves diverse assemblages in multiple localities that represent a range of depositional environments from marginal marine to fully marine, thus presents a unique opportunity to analyze how preservation mode changes throughout a single carbonate Lagerstätte. In Chapter 1, I describe the sedimentology and stratigraphy of Park Head and Hepworth, two Eramosa Lagerstätte localities described more recently, and compare them to the type locality of the Lagerstätte at Wiarton, Ontario. I interpret a depth gradient of the Lagerstätte intervals, with Park Head in the south being the deepest, Wiarton in the north being the shallowest, and Hepworth as an intermediary. In Chapter 2, I describe the preservational pathways of the three distinct biotas of the Eramosa Lagerstätte, and identify taphonomic patterns related to taxonomy and depositional environment. In Chapter 3, I expand our view and for the first time compare the biota of the Eramosa Lagerstätte to 17 Silurian Lagerstätten worldwide. Using cluster analyses, I identify which Lagerstätten biotas are most similar to one another, and compare how varying statistical methodologies and data treatment affects interpretations. Reconstructing past ecosystems using Konservat-Lagerstätten depends on correctly identifying the taphonomic and environmental lenses inherent to their existence. The Eramosa Lagerstätte demonstrates the necessity and opportunity to study this critical time period in Earth history.Ph.D
Preface to the Special Edition on Astroparticle Physics in Canada
Get PDFIt is a pleasure to read these articles that show Canada's international leadership in the field of Astroparticle Physics. The development of the world-leading low-radioactivity environment in SNOLAB following the SNO experiment is providing many opportunities to pursue further properties of neutrinos and to search for interactions of Dark Matter particles. Canadian researchers are also playing significant roles in major experiments at the forefront of this field internationally. Astroparticle Physics has become a major area of particle physics research and it is great to see how the present generation of Canadian scientists are pursuing measurements that appear at or near the top of any ranking of important topics in physics today.
Arthur B. McDonald.
Co-winner of the 2015 Noble Prize in Physics.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
My Easy Authentic Indian One-Pot Vegan Gluten-Free No Mess Weeknight Tamatar Kathak Recipe: Staging Culinary Conceptions through Dinner Theatre
Get PDFThis thesis investigates dinner theatre, a long overlooked hybrid medium of performance. The purpose of this research is to look further into the often untapped possibilities of the form and its potential to communicate narratives about food itself. This was done by collaging existing theory and scholarship from the fields of performance studies and food studies, as well as through the creation and execution of an original piece of dinner theatre. The performance was an exploration of the tomato in Indian cuisine, told through the forms of curry (Indian food) and Kathak (Indian dance). It is scaffolded by theories of food as a vehicle of storytelling, and of liveness and reproducibility in performance. This research cements dinner theatre as an effective and exciting medium to tell the stories of the foods we eat and hopes to see more such stories told in this way.M.A
Risk of Cardiovascular Events in Elderly-Onset Inflammatory Bowel Disease: A Population-Based Matched Cohort Study
Get PDFThe prevalence of inflammatory bowel disease (IBD) in older adults is increasing. Prior studies suggest a heightened cardiovascular risk in IBD patients, yet evidence remains limited in the elderly. We conducted a retrospective, population-based matched cohort study using administrative health data housed at ICES, including Ontario residents aged ≥66 years diagnosed with IBD between 2010 and 2022. Cases were matched with up to 10 controls based on date of birth and sex, and then propensity score (PS) matched to reduce confounding from baseline characteristics. The primary outcome was time to the composite of myocardial infarction, unstable angina, stroke, percutaneous coronary intervention, or coronary artery bypass grafting over a maximum of five years. The study included 3,860 IBD cases and 28,964 matched controls. After PS-matching, we analyzed 3,706 matched pairs. Compared to controls, individuals with IBD experienced a 25% increased hazard of the primary outcome (HR: 1.25, 95% CI: 1.06–1.47).M.Sc
Exploring the Effect of Phospholipase A2 Inhibition on Brain Metabolism and Pathology in a Rat Model of Alzheimer’s Disease
Get PDFCurrent treatments of Alzheimer’s disease (AD) show limited efficacy, making alternative treatments necessary to explore. Magnetic resonance spectroscopy (MRS) studies have shown elevated choline levels in both humans and preclinical AD models, which suggests an increase in cell membrane breakdown by phospholipase A2 (PLA2). PLA2 has also been linked to multiple hallmarks of AD pathology, indicating its inhibition may be beneficial in AD. The present study aimed to explore the effect of PLA2 inhibition in AD via the global PLA2 inhibitor mepacrine. Neurochemistry, behaviour, and pathology were observed within the same animals via MRS, Barnes maze, and immunoreactive staining, respectively. Mepacrine treatment significantly reduced total choline and increased total creatine. Contrary to our expectations, mepacrine treatment did not improve spatial memory or AD pathology. In conclusion, global PLA2 inhibition may lead to metabolically favourable changes in the brains of AD patients without affecting other aspects of AD pathology.M.Sc
MARVEL, is a VHL-, hypoxia-, and HIF-dependent long noncoding RNA that enhances expression of HIF-2α in clear cell renal carcinoma
Get PDFThe Von Hippel Lindau (VHL) tumour suppressor gene is functionally inactive in 90% of clear cell renal cell carcinomas (ccRCC) leading to activation of oxygen-sensing gene regulatory paradigms that are responsible for robust angiogenesis, and resultant tumour growth and metastasis. Hypoxia inducible factor 2 alpha (HIF-2α) is especially relevant to the pathophysiology. The profiling of transcripts expressed in ccRCC tumours has historically focused on RNAs that encode proteins. However, the role of long noncoding RNAs (lncRNAs) in ccRCC pathogenesis, especially their role in the hypoxia signalling pathway, has not been explored. Here we report a comprehensive assessment of lncRNAs differentially expressed when VHL is functionally inactivated and characterize a unique lncRNA transcribed from the long arm of human chromosome 8. MARVEL (Mortality Associated in RCC, VHL-deficient Expressed Long Noncoding RNA) is a VHL-, hypoxia-, and HIF-dependent lncRNA that predicts overall patient survival. Using loss of function and gain of function approaches we provide surprising evidence that MARVEL augments expression of HIF-target genes via pathway feedback regulation of HIF-2α mRNA and protein levels involving RNA elements evident on the 3’-UTR of HIF-2α. These findings uncover a lncRNA mediated mechanism for HIF-2α self-regulation that participates in tumour vascularization and patient outcomes. Therapeutic targeting of the MARVEL lncRNA offers a newer approach to inhibit HIF-2α in ccRCC.Ph.D
Navigating the Gendered Landscape: The Impact of Institutional Participation and Professional Culture in Shaping Inequality
No full textThe Gender Revolution significantly improved women’s status, but recent progress towards equity is “uneven and stalled” (England 2010:149). This dissertation uncovers the complex role of institutional processes in shaping the evolution and persistence of gender inequality. The first study offers a macro-level analysis trends in men and women’s perceptions of mastery across the life course of different cohorts. Perceptions of mastery —control over one’s life— reflect differences in status and gendered notions of agency (Connell 1987; 2005). Institutional participation —educational achievement and employment levels— is key in shaping movement towards and away from gender equality. While high levels of education and employment lead to converging perceptions of mastery, the effect of institutional participation is strongly gendered: women benefitted more from education, while men are penalized more when working less than full-time. Workforce participation emerged as a key driver of men’s higher perceptions of agency in younger cohorts. Drawing on the legal profession as a case study, subsequent studies highlight the role of workplace culture in shaping gender inequality. Using longitudinal data on private sector lawyers, the second paper finds norms of hegemonic masculinity —measured as technical competence, authoritative leadership, work devotion, breadwinner status, and individual preferences— (re)create wage inequality across the earnings distribution. The analysis further uncovers a hierarchy of valuation based on gender and parental status, as fathers earn the highest wage premiums, followed by mothers; women without children earn the least after controls. The final paper investigates how perceptions of professional fit —signaled by professional role confidence (PRC)— shapes perceptions of job security among early-career lawyers. The legal profession is marked by a ‘masculine mystique’ that challenge female lawyers’ PRC —measured as expertise confidence and career fit. Findings indicate that men derive higher perceptions of job security for the same levels of PRC, explaining women’s lower perceptions of job security. Professional fit therefore reinforces gender inequality, possibly through women’s awareness (but not internalization) of their lower status in law. This dissertation provides a nuanced understanding of gender inequality, with institutional participation and culture emerging as key mechanisms shaping the dynamic evolution of gender inequality.Ph.D