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Centenary Republic Day in Istanbul: Eventification of Urban Public Space during a National Day of Celebration
No full textCentenaries represent a significant milestone for nation-states as politically valuable occasions that permeate across public sphere(s), public realm(s), and public space(s). This dissertation examines the centenary of the Republic of Turkey in 2023 by investigating (1) the competing political visions about the state and the society; (2) the centenary’s representation in the mediascape; and (3) public space animation projects in Istanbul by two public institutions aligned with different political factions: the President’s Office and Istanbul Metropolitan Municipality. Using critical event studies and public value theory, this study first focuses on the discursive influences on the construction of the nation, the centenary Republic Day, and the publics at centenary-related events. To this end, it adopts a discourse-analytic approach using speeches from the leaders of main political factions in Turkey during the 2023 election period, and a frame analysis on writings about the centenary published in national newspapers by different media factions. It then examines how public space animation projects of the two public institutions materialized by focusing on the publicness of three animated urban spaces. Through a qualitative analysis of primary visual data, a descriptive account of the parameters of access, security, and design as they are conceived by public institutions and experienced by individuals is provided. While the centenary was commonly positioned as a nation-unifying phenomenon, this study demonstrates that the pre-existing and continuously evolving polarizing mechanisms in politics, media, and society were integral in the construction of the nation and the publics at the events. As such, public space animation projects took significantly different forms. The presidential project, on the one hand, was a spectacle of hard power that deployed recent achievements for passive consumption. On the other hand, the municipal project was a partially interactive celebratory event that positioned the centenary in its historical context. Furthermore, the presidential spectacle aimed to use existing urban amenities without any specific boundaries demarcating the public gathering from the everyday life of the city whereas the municipal event was mostly isolated from its surrounding areas with self-sustaining amenities. The municipal event offered higher flexibility to urban inhabitants’ interactions with the space although the space was less public on a conceived level in terms of its formal features like access and securitization. While publicness is often interpreted through physical spatial features, the experiences on the centenary underscore the decisive influence of symbolic and social features on perceived publicness
Predicting ACL Injuries Using Machine Learning Models and Tibial Anatomical Predictors
No full textThe tibial slope and the tibial depth are well-established risk factors for Anterior Cruciate Ligament (ACL) injury. As ML continues to progress, it has become an increasingly reliable tool for clinical screening and risk factor analysis. This thesis aims to develop and validate an explainable prognostic ML model to predict ACL injury outcomes from these Tibial Anatomical Feature (TAF), and identify the most predictive features among these
parameters.
A dataset comprising Coronal Tibial Slope (CTS), Medial Tibial Slope (MTS), Lateral Tibial Slope (LTS), Medial Tibial Depth (MTD), and sex was constructed using MRI scans taken from 104 subjects (44 males: 22 injured, 22 uninjured; 60 females: 27 injured, 33 uninjured). Two distinct ML pipelines were developed: a self-developed pipeline (including K-Nearest Neighbor (KNN), Support Vector Machine (SVM), Random Forest (RF), XGBoost, CATBoost, Multi-Layer Perceptron (MLP), and TabNet) and an advanced AutoGluon pipeline (including XGBoost, LightGBM, CatBoost, TabPFN, TabM, TabICL, MITRA, and their weighted ensembles). Both were designed as end-to-end pipelines to process the dataset and output predictions with integrated feature importance explanations. Empirically, the AutoGluon Pipeline demonstrated superior performance and training-time efficiency. The recommended F2-tuned standard ensemble achieved an F2-score of 0.736 on the validation set. On the test set, it demonstrated a test balanced accuracy of 0.955, F1-score of 0.952, F2-score of 0.980, ROC AUC of 1.000, precision of 0.909, and recall of 1.000. A full-dataset model, the F2-tuned full-dataset ensemble refitted on the entire dataset for clinical deployment achieved a validation F2-score of 0.813. The global feature importance analyses performed via SHapley Additive exPlanations (SHAP), established the descending order of influences as MTD, LTS, MTS, CTS, and sex.
In summary, the study recommends two versions of the F2-tuned prognostic models, one being a standard ensemble model and the other a full-dataset ensemble. The former, which demonstrated moderately high predictive power, was designed for subsequent research comparison. The latter, without access to the original held-out test set, is constructed for maximum robustness and generalization in real-life clinical deployment. Global feature importance analyses elucidated from the standard ensemble decreased MTD along with increased LTS and MTS as most contributive features for ACL injury. These models serve as both feature attribution tools as well as clinical screening tools. These models are intended to be integrated into clinical practice as explainable machines to assist clinicians in predicting the likelihood of ACL injury
The consequences of high-flexion postures on arterial wave reflections
No full textThis is a post-peer-review, pre-copyedit version of an article published in Journal of Human Hypertension. The final authenticated version is available online at: https://doi.org/10.1038/s41371-025-01088-4Although central wave reflections are critical for aortic pressure regulation, the control mechanisms involved in humans are understudied. This study investigated the impact of upper- and lower-limb high-flexion postures on central arterial wave reflections. Twenty-two healthy adults (11 females, aged 25 ± 3 years) underwent three randomized and counter-balanced positions to evaluate the effect on central wave reflection: supine legs and arms anatomical position; supine two legs bent and arms straight; and supine two arms bent and legs straight. Characteristic impedance, forward and backward pressure waves, and pulse characteristics were measured via the central pressure-flow relationship in the frequency domain at the end of each posture hold. Central diastolic blood pressure increased during arm flexion only (67 ± 9 mmHg vs. 62 ± 9 mmHg; p0.05). Acutely bending the arms and legs did not influence central wave reflections, likely related to a minimal effect of conduit artery bending, versus microvascular involvement, as suggested in previous studies. These findings underscore the importance of identifying the specific vascular regions responsible for wave reflection generation and support the need to refine central pressure augmentation models to accurately localize the dominant sources of wave reflection in humans.Natural Sciences and Engineering Research Council of Canada (RGPIN-2021-02563
Manila's Other City: Toward a Counter-Relocation Approach
No full textThis thesis explores the spatial and economic dynamics of informality in Barangay 105, Tondo, Manila, one of the most densely populated informal settlements in Metro Manila. Located along the industrial edge of the city, the barangay is shaped by rural displacement, state-led resettlement efforts, and infrastructural neglect. At the heart of the site are 25 warehouse structures, originally constructed as temporary relocation housing. Over time, these buildings have been incrementally transformed by residents into permanent live-work spaces, generating a distinct informal morphology that mirrors broader patterns of adaptation across Manila’s socioeconomic landscape.
Informality, in this context, is not peripheral but central to the city’s functioning. Approximately 20–35% of Metro Manila’s population resides in informal settlements, many of which operate as self-sufficient ecosystems in the absence of state support. In Barangay 105, waste picking and small-scale recycling form the core of the local economy. Each day, informal workers collect, sort, and resell large volumes of waste, integrating themselves into larger material flows that connect domestic labor to regional and global waste economies. Despite their critical contributions, these workers remain structurally excluded from planning, labor protections, and service provision. To analyze these dynamics, the research draws on large-scale cartography, detailed studies of urban vernaculars, comparative case studies, and the documentation of daily routines.
Government housing responses have historically relied on mass relocation, often displacing communities to distant peripheries. Programs such as those led by the National Housing Authority (NHA), the Community Mortgage Program (CMP), and the Zonal Improvement Program (ZIP) have repeatedly failed to address the needs of informal residents, instead severing their access to livelihoods and social networks.
This thesis critiques these relocation paradigms and proposes a counter-relocation approach: one that strengthens communities in place rather than removing them. The design focuses on reimagining 15 of the existing warehouse structures as a distributed network of community depots: multi-use infrastructures that embed housing and economic production into the urban fabric. The project centers incremental, solidaristic, and community-led spatial strategies that reflect and strengthen the informal socioeconomic landscape of Tondo
Electrolytes Design for Metal-based Anode Batteries
No full textAqueous zinc-metal batteries (AZIBs) promise intrinsically safe, low-cost energy storage, yet their practical deployment is constrained by interfacial instabilities—hydrogen evolution, corrosion, and dendritic growth—especially under high current density, high depth-of-discharge (DOD), and sub-zero temperatures. This thesis develops an electrolyte-centric roadmap that couple’s solvation-structure regulation with interphase chemistry to stabilize Zn plating/stripping across harsh operating regimes. The approach integrates three mutually reinforcing pillars: (i) outer-solvation-shell tailoring to direct desolvation and crystal orientation, (ii) interphase engineering with multifunctional additives to build robust, ion-conductive SEIs, and (iii) radical management to arrest chemistry that triggers corrosion and gas evolution. Multiscale evidence from synchrotron probes, in-situ/operando imaging, depth-profiling spectroscopies, and simulation closes the loop between molecular design and device-level durability.
First, I introduce an “outer-solvation-shell” strategy using 2-propanol in Zn(OTf)2/H2O that selectively modifies the second solvation environment of Zn²⁺ while preserving the canonical inner shell Zn(H2O)62+. EXAFS/XANES, wide-angle X-ray scattering, NMR, and molecular dynamics consistently indicate water-dominant inner coordination with 2-propanol and OTf- participating in the outer shell. Density-functional theory combined with 2D grazing-incidence XRD reveals preferential adsorption/desolvation pathways on Zn(101)/(002), enabling oriented, compact deposition with lower nucleation barriers. This manifests as markedly extended symmetric-cell lifetimes (≥3000 h at 1 mA cm-2), stable cycling under heavy load (15 mA cm-2 with ~50% DOD), broadened electrochemical stability, suppressed corrosion/HER, and robust low-temperature operation down to −40 °C.
Second, I employ N, S-dual-doped graphene quantum dots (GQDs) as a multifunctional electrolyte/interphase regulator. Their heteroatom sites and surface functionalities coordinate within the solvated layer and at the metal interface to reduce interfacial resistance and homogenize nucleation. Electrochemical analyses (EIS, Coulombic efficiency) and multimodal imaging (in-situ optical/TXM, SEM/FIB-SEM) show dense, void-free deposits and smoother morphology evolution. Depth-profiling (XPS, ToF-SIMS) and diffraction (GIXRD) confirm a ZnF2-rich, mechanically resilient SEI that sustains reversibility under high-rate.
Third, I identify hydroxyl radicals (•OH) as direct drivers of interfacial degradation and demonstrate that free-radical scavengers (FRS) effectively suppress radical-induced corrosion and gassing. EPR verifies radical quenching; cryo-TEM and computed laminography visualize mitigated porous by-product layers and reduced “dead-Zn”; line-scan micro-GIXRD tracks crystallographic evolution during plating/stripping.
When integrated, the three pillars deliver coin cells with high-rate, long-life operation; Zn∥Zn symmetric cells sustaining up to ~1700+ h at ~45–51% DOD; high-areal-capacity cycling (≥5 mAh cm-2 at 2 C for extended cycles); and 17Ah-class Zn∥V2O5 pouch cells. The chemistry is compatible with scalable manufacturing, including dry-electrode processing using Zn powder anodes.
Methodologically, the thesis leverages synchrotron metrologies (VESPERS-GIXRD, HXMA-XAFS, BMIT laminography/TXM), interfacial mechanics (electrochemical-AFM force spectroscopy), and depth-profiling (XPS, ToF-SIMS), complemented by MD/DFT, to establish causality from solvated Zn2+ structure through desolvation kinetics and interfacial reactions to macro-scale durability. Collectively, the results constitute a generalizable design playbook—outer-shell tailoring, interphase engineering, and radical management—that advances fast-charging, low-temperature, and high-DOD AZIBs toward practical, safe, and scalable energy storage
Deterministic and Probabilistic Bijective Combinatorics for Macdonald Polynomials
No full textPermuted-basement Macdonald polynomials ^_(; , ) are nonsymmetric generalizations of symmetric Macdonald polynomials indexed by a composition and a permutation . They form a basis for the polynomial ring ℚ(, )[] for each fixed permutation . They can be described combinatorially as generating functions over augmented fillings of composition shape with a basement permutation .
We construct deterministic bijections and probabilistic bijections on fillings that prove identities relating ^_, ^{ᵢ}_, ^_{ᵢ}, and ^{ᵢ}_{ᵢ}. These identities correspond to two combinatorial operations on the shape and basement of the fillings: swapping adjacent parts in the shape, which expands ^_ in terms of ^_{ᵢ} and ^{ᵢ}_{ᵢ}; and swapping adjacent entries in the basement, which gives ^_ = ^{ᵢ}_ when ᵢ = ᵢ₊₁
Short-Pulsed Laser Processing of Metal-Oxide Nanomaterials: Role of Defects in Properties, Nanojoining and Sintering
No full textMetal-oxide nanomaterials are promising candidates for next-generation nano-electronic and optoelectronic devices due to their tunable band structures, multifunctionality, and chemical stability. However, their practical deployment is limited by intrinsic challenges such as low plasticity, brittleness, poor conductivity, and difficulties in reliable integration. Central to these limitations is the role of point, line, and interfacial defects, which govern charge transport, plastic deformation, diffusion, and bonding at multiple length scales. Controlling and engineering these defects without degrading structural integrity is therefore essential for unlocking the full potential of metal-oxide nanomaterials.
This thesis investigates ultra-short (femtosecond) and short (nanosecond) pulsed laser irradiation as versatile strategies to manipulate defect landscapes and interfacial behavior. The highly localized, non-equilibrium energy delivery of pulsed lasers enables two complementary pathways: (i) defect engineering to enhance intrinsic mechanical and electrical properties, and (ii) defect-assisted diffusion to promote nanojoining and low-temperature and rapid sintering.
Both nanosecond and femtosecond laser treatment can significantly influence the properties of individual CuO nanowires, but through fundamentally different mechanisms. Nanosecond laser pulses generate a moderate density of vacancies and dislocations that, with heat accumulation and partial annealing, reorganize into dislocation loops. This defect rearrangement converts a brittle, predominantly elastic response into elastic–plastic behavior, modestly increasing ductility and improving carrier mobility while maintaining structural stability. In contrast, femtosecond laser irradiation operates under a highly nonthermal regime, generating a supersaturated nonequilibrium defect density comprising abundant vacancies and densely interconnected dislocation networks. The excess vacancies enhance point-defect mobility, facilitating dislocation climb and cross-slip, while the internal stress fields within the dislocation network reduce nucleation barriers and promote glide and multiplication. Collectively, these mechanisms drive a brittle-to-plastic transition, resulting in stable plastic flow, greater deformability, and improved fracture resistance.
By enhancing both the plasticity and electrical conductivity of CuO nanowires, laser treatment creates favorable conditions for single-nanowire device applications. Furthermore, it serves as an effective pre-treatment step before integration, mitigating the intrinsic brittleness of metal oxide nanowire and enabling reliable assembly and reuse in nanoscale systems.
At the integration level, both lasers were used to fabricate functional nanodevices. Nanosecond laser treatment enabled precise cutting and rejoining of CuO nanowires by controlling defect network formation, leading to flexible, conductive CuO–CuO junctions suitable for strain-sensing applications. Similarly, it facilitated the fabrication of robust CuO–ZnO p–n junctions for photodetector devices, where thermal effects improved interfacial diffusion and bonding strength. In contrast, femtosecond laser treatment promoted non-thermal nanojoining through a two-step mechanism: first inducing localized plasticity via defect formation and then achieving strong joints without a heat-affected zone or phase transformation through shot-peening-assisted bonding.
To assess the role of defects in diffusion, defect-assisted sintering was investigated using nanosecond laser pre-treatment of TiO₂ nanopowders. Optimizing the laser parameters led to partial annealing of laser-generated dislocations and recrystallization into ultrafine grains. These microstructural modifications increased the density of high-angle grain boundaries, creating short-circuit diffusion pathways that enhanced mass transport during sintering. Consequently, efficient densification was achieved at 750 °C, approximately 250 °C lower than conventional thermal furnace sintering (~1000°C). In contrast, femtosecond laser pre-treated TiO₂ nanoparticles generated a high concentration of oxygen vacancies that reorganized into dislocation-coupled vacancy channels, facilitating pipe-diffusion–dominated mass transport. This rapid and nonthermal diffusion pathway enabled fast neck growth and densification within only 10 minutes at 650 °C, demonstrating the crucial role of laser-induced defects in accelerating diffusion and achieving rapid low-temperature sintering of metal oxides.
Overall, this work establishes pulsed-laser irradiation as a powerful platform for defect engineering in metal-oxide nanomaterials
Computational Insights into the Corrosion Behavior of NbTaMoW and NbTaMoWV High-Entropy Alloys in Molten Fluoride Salts
No full textMolten salt reactors (MSRs), one of the six next-generation nuclear reactor designs, employ molten fluoride salts as the coolant and/or fuel solvent when operated in a thermal-neutron spectrum, and offer higher thermal efficiency compared to today’s water-cooled reactors. Nonetheless, the elevated temperatures, corrosive nature of salts, and high neutron irradiation in MSRs create a harsh environment for structural materials. The influx of impurities, namely moisture, into the molten salt medium has long been shown to exacerbate the corrosivity of fluorides. Owing to their superior thermal and mechanical robustness, refractory high-entropy alloys with a body-centered cubic (BCC) structure have been proposed as candidate containment materials for MSRs. Nonetheless, the degradation of these advanced materials in molten fluorides is an intricate process whose underlying mechanisms remain poorly understood. This study explores the corrosion behavior of BCC (100)-NbTaMoW and (100)-NbTaMoWV surfaces in pure and hydrated FLiBe salt via density functional theory and ab initio molecular dynamics simulations. Electronic structure analyses, including density of states and crystal orbital Hamilton population, provide insight into the interfacial bonding and charge transfer. Irrespective of salt purity, NbTaMoW exhibits minimal d-band shifts which highlight its electronic stability, and weak interactions with fluorine and oxygen. The addition of vanadium to form NbTaMoWV further diminishes susceptibility to oxidation and enhances stability at the salt interface, suggesting superior corrosion resistance in both pure and hydrated salt
Induced subgraphs and tree decompositions VI. Graphs with 2-cutsets
No full textThe final publication is available at Elsevier via https://doi.org/10.1016/j.disc.2024.114195. © 2025. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/This paper continues a series of papers investigating the following question: which hereditary graph classes have bounded treewidth? We call a graph t-clean if it does not contain as an induced subgraph the complete graph Kt, the complete bipartite graph Kt,t, subdivisions of a (t x t)-wall, and line graphs of subdivisions of a (t x t)-wall. It is known that graphs with bounded treewidth must be t-clean for some t; however, it is not true that every t-clean graph has bounded treewidth. In this paper, we show that three types of cutsets, namely clique cutsets, 2-cutsets, and 1-joins, interact well with treewidth and with each other, so graphs that are decomposable by these cutsets into basic classes of bounded treewidth have bounded treewidth. We apply this result to two hereditary graph classes, the class of (ISK4, well)-free graphs and the class of graphs with no cycle with a unique chord. These classes were previously studied and decomposition theorems were obtained for both classes. Our main results are that t-clean (ISK4, wheel)-free graphs have bounded treewidth and that t-clean graphs with no cycle with a unique chord have bounded treewidth.NSF, Grant DMS-1763817 || NSF-EPSRC, Grant DMS-2120644 || NSERC, RGPIN-2020-03912
Injustices in the Hijab Debates: Orientalist, Ideological, and Epistemic Injustices in Dominant Hijab Discourse
No full textIn this dissertation, I analyze epistemic injustices and ideological factors that block or obscure contemporary public discourse about the Islamic veil (or hijab) and contribute to the marginalization of Muslim women and all Muslims. I begin with an overview of Edward Said’s theory of Orientalism, and I include a focus on Orientalist myths and frameworks, including the ‘Clash of Civilizations’ and the more recent ‘War on Terror’. I zoom in on Orientalist examples that highlight the gendered dimension of colonial discourses and misrepresentations of the veil. In addition to Orientalism, I substantiate my analyses with the theory of Unknowability, mainly following Kristie Dotson and Kyle Whyte’s (2013) account. I utilize the framework of Unknowability to clarify the marginalization experienced by Muslims and Muslim women. I then move on to a deeper investigation of current discourse on the hijab, zooming in on the Orientalist myth that claims the veil is “unique to Muslim women,” and Martha Nussbaum’s (2012) pro-burqa ban arguments. In my analysis of this Orientalist myth, I demonstrate how both Western interests and the Islamic Right—via a flipped Orientalism—benefit from it. In examining Nussbaum’s arguments, I show that they reproduce many Orientalist and epistemic injustices long identified by feminist, decolonial, Black and Indigenous scholars, and other scholars of colour. As a result, her discussion dangerously serves the marginalization of Muslim women and Muslims more broadly.
In the last two chapters, I shift my focus to the intra-Muslim context. I examine the hijab as a social practice embedded within cultural scripts and social structures by expanding on Fatema Mernissi’s (1991) account of the hijab and by utilizing Sally Haslanger’s (2017; 2018) account of social practices. Deconstructing the hijab in this way provides a framework for navigating the features and modalities of the hijab and makes clearer the potential weight the practice has for Muslim women. Lastly, I examine the hermeneutical impasse between Muslim feminist advocates of the hijab and Muslim feminists critical of the hijab, focusing on the global movements ‘World Hijab Day’ and ‘No Hijab Day’ to do so. I introduce the 3rd Party Impasse to capture this case, and I demonstrate that this hermeneutical impasse is caused by each group’s need to prioritize their resistance against different third parties