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Strategies for Powerful Quantum-Enabled Bitcoin Miners
No full textBitcoin miners equipped with purpose-built quantum computers that execute Grover’s algorithm on classical candidate blocks, measuring the resulting quantum state to yield a potentially valid proof-of-work, pose a threat to Bitcoin’s security against 51% attacks. I aim to assess this threat by employing a game-theoretic framework inspired by the Lee-Ray-Santha quantum races model, extending it to better reflect how quantum miners would behave in practice. These extensions address some of the simplifications of prior works, where quantum miners performed only one quantum measurement (which does not maximise their resources), and were assumed to employ a peaceful strategy, wherein the quantum miners discard the resources already invested into searching upon receiving a broadcast of a newly-mined block (which is not enforceable). I consider a setting in which the quantum miners perform multiple quantum measurements between successive blocks, employ Sattath’s Aggressive Quantum Mining Strategy (AQMS), and must allocate limited quantum resources across these measurements. When employing Sattah’s AQMS, a quantum miner halts their execution of Grover’s algorithm and measures the resulting quantum state upon receiving a broadcast of a newly mined block, attempting to create a temporary fork and thereby decreasing the effective hash rate required for a 51% attack. In this novel setting, I derive the payoff matrices for the quantum miners and compute optimal quantum mining strategies that correspond to Nash equilibria. I simulate the deployment of these optimal quantum mining strategies within the Bitcoin network and estimate their effect on Bitcoin’s security against a 51% attack. I determine how two quantum miners should optimally allocate their quantum resources based on the network difficulty. Overall, I find that even when behaving optimally, two quantum miners cannot create enough temporary forks to render the Bitcoin network vulnerable to this quantum threat, given realistic constraints on their quantum resources. This thesis contributes to the growing body of research on the potential threats posed by scalable quantum computers, using the case of two quantum miners as a step toward understanding how quantum miners in general could affect Proof-of-Work-based cryptocurrencies like Bitcoin
Some problems related to the polytope illumination
No full textThis thesis is a collection of results concerning the Illumination Conjecture and the combi- natorial structure of C-polyhedra. These results were developed both independently and in collaboration with my Supervisor, Dr. Károly Bezdek and a fellow graduate student, Cameron Strachan. The Illumination Conjecture concerns convex bodies in Euclidean space Ed . A direction u in the origin-centred unit sphere S^{d−1} illuminates a boundary point x of a convex body K, if the ray with direction u, that starts at x, has a nonempty intersection with the interior of K. A convex body K is illuminated by directions u_1 , . . . , u_n ∈ S^{d−1} if every boundary point of K is illuminated by some direction u_i , 1 ≤ i ≤ n. Illumination number of a convex body K, denoted by Ill(K), is the smallest number of directions that illuminate K. The Illumination Conjecture states that the illumination number Ill(K) of a d-dimensional convex body K ⊂ E^d is at most 2^d , and Ill(K) < 2^d if K is not an image of a d-cube under some linear transformation. In this thesis, we prove the Illumination Conjecture for the origin-symmetric cap bodies of a ball in E^3 , E^4 , and E^d , d ≥ 19. We also prove the upper bound Ill(K) ≤ 4d for the unconditionally symmetric cap bodies in an arbitrary dimension d ≥ 5. Furthermore, we obtain the upper bound Ill(K) ≤ 12 for the cap bodies of a ball in E^3 . Next, we prove the Illumination Conjecture for the primitive polytopes. A bounded intersection of halfspaces is a primitive polytope, if omitting any halfspace renders the intersection unbounded. A C-polyhedron P ⊂ E^d is a reduced, d-dimensional intersection of homothets of a smooth, strictly convex body C ⊂ E^d . A fa-C-t of P is a connected smooth subset of bd P that is not contained in another smooth connected subset of bd P . We prove that any C-polyhedron, that is the intersection of two homothets, has exactly two fa-C-ts. Next, we prove that a C-polygon P ⊂ E^2 , that is an intersection of n translates of C, has exactly n fa-C-ts. We also prove that a C-polygon P ⊂ E^2 , that is an intersection of n homothets of a smooth strictly convex body C ⊂ E^2 , has at most 2n − 2 fa-C-ts
Biosensor Applications of Self-assembled Monolayers of N-heterocyclic Carbenes
No full textElectrochemical biosensors that incorporate Toll-like receptors (TLRs) as the biorecognition element are an important class of pathogen biosensors, enabling broad-spectrum detection. These biosensors immobilize TLR proteins onto electrode surfaces using self-assembled monolayers (SAMs), most commonly alkanethiol SAMs on gold, to produce well-defined interfaces capable of transducing binding events into electrochemical signals. N-heterocyclic carbenes (NHCs) have recently emerged as an alternative class of materials for the formation of SAMs on metals. This thesis introduces NHCs as a next-generation SAM platform for TLR4 biosensors to detect Gram-negative bacteria. The results show that NHCs overcome many of the limitations of thiol-based SAMs while also revealing advantageous properties not previously associated with SAM-based interfaces. The thesis begins with the fabrication of a first-generation TLR4 impedimetric biosensor based on NHC SAMs on planar gold substrates. Through a side-by-side comparison with a thiol-based TLR4 biosensor, it is demonstrated that the NHC-based biosensor offers not only improved analytical performance but also superior operational stability over 36 hours of operation in the measurement medium, directly addressing the long-standing problem of baseline drift in thiol-based biosensors. After establishing their advantages on planar electrodes, NHC SAMs were integrated with nanostructured architectures, including gold nanoparticle-decorated indium-tin oxide (AuNP/ITO) and nano-roughened gold (NR-Au). After functionalization with TLR4/NHC layers, these nanostructured Au-based sensors yielded up to four-fold higher sensitivity and five-fold lower limits of detection compared with planar gold. A major contribution of this thesis is the extension of NHC chemistry to carbon electrode materials, addressing the long-standing absence of a predictable, monolayer-forming analogue to thiol-based SAMs on gold. It is shown that structurally diverse NHCs form uniform, chemisorbed monolayers across a wide range of carbon substrates, including highly defective and nanoporous powders. These NHC-modified carbons exhibit tunable coverage, long-range molecular order consistent with SAM formation, and exceptional electrochemical and thermal stability, enabling the first demonstration of a TLR4 biosensor on an everyday carbon. Finally, this thesis reveals a previously unrecognized property of NHC SAMs, namely a reversible, electrolyte-dependent modulation of interfacial charge-transfer kinetics driven by chaotropic anions. This adaptive ion-responsive behavior expands the fundamental understanding of NHC-based monolayers and opens opportunities for stimuli-responsive electrochemical interfaces
Towards Adaptive and Resource-Efficient Live Volumetric Video Streaming
No full textVolumetric video enables fully immersive six-degrees-of-freedom (6DoF) experiences. Still, its adoption in real-time applications remains limited by extreme bandwidth demands, high computational cost, and stringent end-to-end latency requirements. This thesis investigates these challenges and introduces three complementary systems—LiV, Super-VV, and RapidX—that collectively advance the practicality, scalability, and resource efficiency of live volumetric video streaming. We first introduce LiV, a server-side adaptive streaming framework integrating viewport-aware tiling, encoding-time prediction, and a Mixed-Integer Linear Programming (MILP)-based quality selector within a Dynamic Adaptive Streaming over HTTP (DASH) architecture. By jointly considering network dynamics, computational constraints, and the user viewpoint, LiV delivers stall-free, high-quality live volumetric video while achieving substantial bitrate savings without compromising interactivity. Next, we present Super-VV, a lightweight, end-to-end pipeline that combines quality-preserving downsampling, tile-parallel Draco compression, and a central processing unit (CPU)-based super-resolution upsampler to significantly reduce bitrate while maintaining perceptual fidelity. Through a pipelined and in-memory architecture, Super-VV achieves real-time throughput on commodity hardware and reduces bandwidth consumption by up to 98% while preserving high visual quality. We then introduce RapidX, a modular testbed for constructing and evaluating complete capture-to-render pipelines under realistic compute and network conditions. RapidX simplifies system prototyping through containerized workflows and enables controlled evaluation of volumetric streaming systems across diverse scenarios. Together, these contributions demonstrate that adaptive, resource-efficient live volumetric video streaming is achievable through coordinated optimization across compression, adaptive delivery, and system-level orchestration. This thesis moves volumetric streaming closer to widespread deployment in telepresence, augmented reality (AR), virtual reality (VR), and immersive communication applications
Theatre Assessment Instructions and Rubric
No full textTheatre of the Oppressed group research project instructions and grading criteria
Constellations of Self: A Practice-as-Research Exploration of Embodiment, Emptiness, and First Generation Immigrant Experience
No full textThis thesis is a practice based exploration of selfhood as I have experienced it as a first-generation immigrant living in Calgary, Alberta. Rather than seeking to define the self or trace a linear account of how it develops, the project dwells in the ongoing question of what the self is and how it becomes perceptible through lived experience, embodied inquiry, and creative process. The work emerged from a discomfort with fixed ideas of identity and from my own experience of navigating multiple cultural, linguistic, and perceptual worlds as a multiethnic Indo Iranian immigrant who has lived in several countries, including Japan. These experiences revealed selfhood not as a coherent or stable entity but as something fluid, relational, and continually reconstituted. The research approaches this inquiry through performance as a mode of knowledge production. Drawing on Madhyamaka Buddhist thought, Michael Chekhov’s psycho physical actor training, culturally resonant dance forms such as Waving, Popping, Bhangra, and Azeri dance, and embodied principles from the Alexander Technique, the project investigates how movement, imagination, and sensory awareness can open alternative ways of sensing and understanding selfhood. Nervous system regulation emerged as a significant condition for accessing depth, presence, and creative responsiveness, informing both the movement practice and the broader investigation of the self. Situated within a Practice as Research framework, the thesis uses cycles of experimentation, reflection, improvisation, and remaking to generate knowledge through creative process. The creative component consists of a script and a series of performance fragments developed during studio work, and exploratory sessions. The written component contextualizes this process through philosophical inquiry, methodological explanation, and critical reflection on the discoveries, tensions, and shifts that shaped the work. Together, they propose that selfhood can be understood not as a fixed identity but as a lived question that becomes sensible through performance, relationality, and sustained inquiry
Mass EV adoption and Gas Station Closures: A Network-Based Analysis for Calgary
No full textIn response to global environmental concerns and Canada’s ambitious climate policies, a rapid transition from internal combustion engine (ICE) vehicles to electric vehicles (EVs) is underway. Statistics Canada data show a strong shift toward electrified vehicles over the past five years. Compared to the same quarter in 2020, new registrations in Q2 2025 increased by approximately 375% for battery-electric vehicles, 441% for plug-in hybrids, and an even sharper 929% for conventional hybrids. This sustained multi-fold growth highlights the accelerating pace of electrification, even as internal combustion vehicles remain a significant share of the fleet during the transition period. This research examines how this transition affects gasoline refueling accessibility for remaining ICE drivers in Calgary and other major Alberta cities. Using a quantitative geospatial methodology, the study integrates ArcGIS network analysis with Monte Carlo simulations of gasoline-station closures to measure additional detour distances required for refueling as EV adoption leads to gasoline demand reduction and station viability. The simulation framework quantifies how gasoline-station contraction increases refueling burden, using trip-weighted mean detour as the primary metric. It also identifies transition points using curve-based markers, indicating when the network shifts from robust to configuration-sensitive and eventually operationally inadequate. Although the analysis focuses explicitly on refueling accessibility rather than traffic modeling, the findings carry broader implications for transportation planning. Increasing detours and localized refueling gaps can influence route choice, commuter reliability, and mobility equity for ICE users during the transition period. The results therefore support proactive planning for infrastructure adaptation as EV adoption accelerates. By identifying when and where refueling accessibility becomes strained, this study provides a data-driven foundation to support municipal planners and policymakers. Its insights can guide strategic station retention, deployment of hybrid refueling sites, and coordinated expansion of EV charging infrastructure, contributing to a balanced, efficient, and equitable transition aligned with Canada’s long-term decarbonization goals
Catalytic Antioxidant Activity of Acyclic and Macrocyclic Selenides - Insights into Structure-Activity Relationships and Mechanisms from Kinetic and Computational Studies
No full textNatural Sciences and Engineering Research Council (NSERC
Developing an expert consensus statement on emergency preparedness for cancer care delivery in Canada: a modified Delphi study
No full textAbstract Background In response to the COVID-19 pandemic, health organizations around the world including those in Canada have developed guidelines to allow for cancer care delivery amid a public health emergency. In Canada many of these guidelines were developed during the pandemic and at a time when there were limitations in knowledge on the impact of certain policies on patient care. Built upon this foundation we aimed to establish expert-informed, consensus-based policy recommendations to improve the preparedness and resilience of cancer systems for future public health emergencies, using lessons learned from the COVID-19 pandemic and focusing on the Canadian cancer care systems. Methods We conducted a modified Delphi study using a two-round online survey administered to a Steering Committee composed of a purposefully sampled group of physicians and a patient advisor from across Canada. Participants rated their agreement with 23 Delphi statements across four domains: access to cancer surgery, virtual and home care, primary care, and institutional memory. These statements were developed through a focus group discussion with an Advisory Committee composed of Canadian health policy leaders during the COVID-19 pandemic and refined based on qualitative feedback. Consensus was defined a priori as greater than 70% agreement (6 or 7 on a 7-point Likert scale). Results Seven of the 15 individuals invited to be panelists of the Advisory Committee and 16 of the 29 individuals invited to be panelists of the Steering Committee agreed to participate. Ten of the 23 statements reached consensus, including strengthening interhospital collaboration for surgical access, identifying health services appropriate for virtual care, expanding at-home cancer screening, and reducing administrative burden through artificial intelligence. In contrast, proposals related to primary care reform and infrastructure expansion did not achieve consensus. Qualitative responses revealed that disagreement mostly centered on perceived jurisdictional responsibility and resource constraints. Conclusion We identified expert consensus on ten priorities that extend beyond immediate recovery and support system resilience. These recommendations may offer a foundation for healthcare leaders to impact national and international policymaking
Role of NF-κB in the up-regulation of IKKε and IRF1 by inflammatory cytokines in pulmonary epithelial cells
No full textAsthma is characterized by chronic lung inflammation. In severe asthma, lung inflammation is poorly controlled by inhaled glucocorticoids, the mainstay therapeutic in asthma. Since airway epithelial cells (AECs) are the main target of inhaled glucocorticoids, primary human AECs and pulmonary epithelial cell lines treated with inflammatory cytokines (IL-1β and TNF⍺) were used to activate the canonical NF-κB cascade, which is a central mediator of inflammatory gene expression. While generally well defined, how the NF-κB cascade contributes to the expression of inducible signalling components such as IκB kinase ε (IKKε) and interferon regulatory factor 1 (IRF1) are not described. Since IKKε and IRF1 also evade full repression by glucocorticoids, their expression may be relevant to severe disease. In aim 1, cytokine activation of the canonical NF-κB signalling pathway increased the expression of IKKε. Three regions at the IKKε locus (IKBKE) bound NF-κB (p65) and, when cloned, drove reporter activity that depended on NF-κB motifs. Since IKKε activation (p-IKKε, p-IRF3) was not markedly induced by IL-1β stimulation, the increased IKKε expression may constitute a signalling cascade that could prime cells to respond to other stimuli. A similar analysis in aim 2 revealed that the canonical NF-κB signalling pathway also drove the expression of IRF1. Four DNA regions upstream of IRF1 bound p65 and were able to drive reporter activity that depended on NF-κB motifs. Once induced by NF-κB, IRF1 translocated to the nucleus and led to IRF-dependent transcriptional activity. In the final results section, genome-wide analysis of IRF1 binding to DNA revealed enrichment at innate immune and anti-viral genes. Among these, CXCL10 and TAP1 were confirmed to be IRF1-dependent in a pulmonary cell line. These genes were also upregulated by IL-1β in primary human AECs, supporting the physiological relevance of this mechanism. Since IRF1 itself was not strongly repressed by glucocorticoids, some IRF1-dependent genes could also escape glucocorticoid-mediated repression. Taken together, this study reveals mechanisms behind the upregulation of innate immune genes in AECs that may be important for host-defence, but which could also contribute to inflammation in severe disease