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100 mile fibre: The organization and governance of fibresheds in Southern Ontario and Northern Ohio
No full textTextile overconsumption, propelled by a fashion industry that is global in scale and overly reliant on non-renewable feedstocks, has led to new models of fibre production. One model is the fibreshed, a regional-based fibre system that proposes circularity, local scale and suitability, and accessible mechanisms of governance. While fashion and design scholars have studied fibresheds, more research is needed to develop a theoretical understanding of them, their structures of governance and their contributions to sustainable fashion. To address these gaps, a case study was conducted on two fibreshed networks in North America. This research examined how the model is being delivered and the factors influencing its implementation, in particular, how regional fibre production is structured, managed and supported in two regions – Southern Ontario and Northern Ohio – areas which include the organizations of Upper Canada Fibreshed in Ontario and Rust Belt Fibershed in Ohio. Informed by existing scholarship in fashion, sustainable fashion and governance, and by theories on place and regions, this exploratory work involved interviews with key informants and a review of primary documents to draw an empirical understanding of the organization and governance of fibresheds. More specifically, it applied Benedum and Becker’s (2021) network governance framework to assess how fibreshed players organize, coordinate stakeholders and carry out their objectives of social accountability and regional development. By integrating sustainable fashion concepts with regional theories from geography and design, the results of this research emphasize the social-spatial dimensions of fibresheds. They also inform the study of other regional-based supply networks by reinforcing the impact of heterogeneity on network capacity and the need for producer involvement in decision-making. Such an analysis provides a critical foundation for progress toward the governance of sustainable fashion which values the players and leads to more meaningful engagement with sustainable consumption
LiDAR-based 3D Perception from Multi-frame Point Clouds for Autonomous Driving
No full text3D perception is a critical component of autonomous driving systems, where accurately detecting objects and understanding the surrounding environment is essential for safety. Recent advances in Light Detection and Ranging (LiDAR) technology and deep neural network architectures have enabled state-of-the-art (SOTA) methods to achieve high performance in 3D object detection and segmentation tasks. Many approaches leverage the sequential nature of LiDAR data by aggregating multiple consecutive scans to generate dense multi-frame point clouds. However, the challenges and applications of multi-frame point clouds have not been fully explored. This thesis makes three key contributions to advance the understanding and application of multi-frame point clouds in 3D perception tasks.
First, we address the limitations of multi-frame point clouds in 3D object detection. Specifically, we observe that increasing the number of aggregated frames has diminishing returns and even performance degradation, due to objects responding differently to the number of aggregated frames. To overcome this performance trade-off, we propose an efficient adaptive method termed Variable Aggregation Detection (VADet). Instead of aggregating the entire scene using a fixed number of frames, VADet performs aggregation per object, with the number of frames determined by an object's observed properties, such as speed and point density. This adaptive approach reduces the inherent trade-offs of fixed aggregation, improving detection accuracy.
Next, we tackle the challenge of applying multi-frame point cloud to 3D semantic segmentation. Point-wise prediction on dense multi-frame point clouds can be computationally expensive, especially for SOTA transformer-based architectures. To address this issue, we propose MFSeg, an efficient multi-frame 3D semantic segmentation framework. MFSeg aggregates point cloud sequences at the feature level and regularizes the feature extraction and aggregation process to reduce computational overhead without compromising accuracy. Additionally, by employing a lightweight MLP-based point decoder, MFSeg eliminates the need to upsample redundant points from past frames, further improving efficiency.
Finally, we explore the use of multi-frame point clouds for cross-sensor domain adaptation. Based on the observation that multi-frame point clouds can weaken the distinct LiDAR scan patterns for stationary objects, we propose Stationary Object Aggregation Pseudo-labelling (SOAP) to generate high quality pseudo-labels for 3D object detection in a target domain. In contrast to the current SOTA in-domain practice of aggregating few input frames, SOAP utilizes entire sequences of point clouds to effectively reduce the sensor domain gap
On the complexity of feasibility, connectivity, and -isogeny computation
No full textAlgebraic geometry has several real-world applications, including automation and robot motion planning, control theory, as well as in the foundations of certain post-quantum cryptosystems. For example, isogeny-based cryptography is built on the computational difficulty of finding isogenies between elliptic curves. This thesis investigates complexity in computational algebraic geometry, particularly bit-complexity questions in real algebraic geometry, and 2^a-isogeny computation on Legendre curves. Analyzing the bit complexity enables the development of modular extensions that manage the growth of intermediate expressions, making implementations more efficient in practice for real-world applications.
The main contributions are as follows.
1. We analyze the bit complexity of an algorithm that computes one point per connected component in a real algebraic set. The analysis is of an algorithm by Safey El Din and Schost (Polar varieties and computation of one point in each connected component of a smooth real algebraic set). This algorithm uses random changes of variables that are proven to generically ensure certain desirable geometric properties such as weak transversality and Noether position for polar varieties. The cost of the algorithm was given in an algebraic complexity model. We analyze the bit complexity and the error probability, and we provide a quantitative analysis of the genericity statements.
2. The Chinese Remainder Theorem (CRT) is used in developing modular algorithms, controlling the growth of intermediate expressions by performing computations modulo a number of small primes, and then reconstructing the output modulo the product of the primes. Some unlucky primes produce errors by returning incorrect results or no result. We can bound their number by finding a nonzero U in Z with the property that all unlucky primes divide U.
Without allowing for errors, the CRT-based modular algorithms requires all primes to be lucky, which typically results in larger primes. Error-correction techniques allow a small number of unlucky primes, therefore reducing the prime size. We provide a quantitative analysis that gives explicit sufficient conditions on the number and size of the primes to ensure a given success probability, when given a height bound H on the output and the integer U bounding the number of unlucky primes. We also demonstrate some applications.
3. We give bit-size estimates for computing roadmaps in smooth bounded real hypersurfaces. Roadmaps are used to decide if two points in a real algebraic set are continuously connected by a path from one point to the other, and therefore have applications in robot motion planning by deciding if paths exist between points.
To obtain our height estimates, we apply tools from intersection theory that involve the arithmetic Chow ring, developed by D’Andrea, Krick, and Sombra.
4. We introduce a method for efficiently computing 2^a-isogenies in Legendre form with applications in post-quantum cryptography. The majority of work on isogeny computation uses elliptic curves in Montgomery form. To the best of our knowledge at the time of writing, elliptic curves in Legendre form had not yet been explored for isogeny-based cryptography. Legendre form is an interesting family to study, having a very simple defining equation, and the simplest possible representation of the 2-torsion subgroup
Investigation of the therapeutic potential of a new phytoceutical for lymphopenia in Barth Syndrome
No full textBackground: Barth syndrome (BTHS) is a debilitating X-linked genetic disorder caused by mutations in the gene that encodes for Tafazzin, an enzyme important for cardiolipin (CL) remodeling. This disorder impairs the ability to modify fatty acyl chains on cardiolipin after de novo synthesis, resulting in decreased cardiolipin levels and alterations in cardiolipin fatty acyl composition. Given that CL is crucial for mitochondrial processes, TAFAZZIN mutations lead to abnormal mitochondrial ultrastructure, impaired dynamics, and decreased electron transport chain capacity. As a result, tissues with high energy demands, including the heart, skeletal muscle, and immune system, are most affected by BTHS. While BTHS research has traditionally focused on innate immune dysfunction, recent studies highlight potential adaptive immune impairments. Data from my MSc research demonstrated that transformed B-lymphoblasts derived from individuals with BTHS exhibit significantly reduced growth compared to sex- and age-matched healthy controls. This deficit was partially restored with the endocannabinoid N-oleoylethanolamide (OEA). However, while OEA showed initial promise, it only partially rescued the impaired clonal expansion of these cell lines. In the pursuit of compounds with potentially better efficacy and safety profiles, further investigations turned to a natural phytochemical known for its antioxidant and mitochondrial-modulating properties, which we refer to as Compound X.
Aims and Approach: This thesis aimed to evaluate the therapeutic potential of Compound X in treating BTHS-associated lymphopenia. To achieve this, several objectives were examined by comparing responses in both BTHS and healthy B-lymphoblasts. Specifically, we: (1) assessed the effects of Compound X on cell growth using manual cell counting with a hemocytometer; (2) analyzed changes in CL content and composition following Compound X treatment via thin-layer chromatography and gas chromatography (TLC-GC); (3) evaluated the expression of genes involved in CL biosynthesis using RT-qPCR; (4) examined the impact of Compound X on ETC protein subunit levels using immunoblotting; and (5) investigated alterations in mitochondrial ultrastructure and morphology in response to Compound X treatment through transmission electron microscopy (TEM) and immunoblotting of fission and fusion mediators.
Results: In the first study, Compound X treatment fully restored the impaired cell expansion of B-lymphoblasts derived from five distinct BTHS donors, bringing the cell number to near levels of healthy controls. This growth improvement was accompanied with significant increases in the maximal coupled state III respiration in BTHS B-lymphoblasts, in which all five tested BTHS donors had increased mitochondrial membrane potential following Compound X treatment. Further analysis revealed that Compound X treatment restored total CL content of BTHS B-lymphoblasts to healthy levels, but did not significantly alter the relative proportions of the major CL fatty acyl species. At the protein level, Compound X treatment reversed the decreased expression of major ETC subunits, including succinate dehydrogenase subunit A (SDHA), cytochrome c oxidase subunit 1 (COX1), and cytochrome c oxidase subunit IV (COXIV). TEM analysis of three distinct BTHS donor cell lines showed that BTHS lymphoblasts had abnormal cristae patterns with smaller total cristae lengths and enlarged mitochondria compared to healthy controls. While Compound X treatment did not significantly increase the length of cristae, it significantly reduced the mitochondrial enlargement in BTHS B-lymphoblasts. Lastly, immunoblotting of fusion mediators revealed elevated OPA1 levels in BTHS lymphoblasts, while analysis of the fission mediator DRP1 revealed elevated phosphorylation of its inhibitory site at Serine 637, both of which were significantly attenuated by Compound X treatment, suggesting a potential role for this compound in restoring mitochondrial dynamics in BTHS B-lymphoblasts.
Conclusion: These findings demonstrate for the first time that Compound X effectively rescued the observed impairments in B-lymphoblast cell expansion in BTHS and partially restored BTHS B-lymphoblast mitochondrial function and morphology. However, additional experimentation in both animal models and humans are needed to further validate the therapeutic efficacy of Compound X in BTHS lymphopenia
Protecting Environmental and Cultural Water Through Collaborative Governance and Impact Assessment: International, Canadian, and Saskatchewan Examples
No full textHuman activities and climate change threaten freshwater resources and Indigenous rights. Developments (e.g., irrigation, dams, mines) cumulatively pollute and alter the hydrology of fresh water, affecting ecosystems (environmental flow/water) and Treaty and Inherent Rights (cultural flow/water). However, development assessment and management may not guarantee the protection or connectivity of water downstream. Regional sustainability-based guidance is needed through collaboration between Crown and Indigenous governments. Through interviews, workshops, ecohydrology, and policy analysis, this dissertation investigates strategies for collaborative governance and impact assessment to protect water for the environment, human uses, and Indigenous rights at three scales: globally, nationally (Canada), and regionally (Saskatchewan’s Treaty Four). Treaty Four studies were co-created with File Hills Qu’Appelle Tribal Council’s Lands, Resources, Environment, and Stewardship Department (Ch. 2) and informed the design of global and Canadian studies. I systematically reviewed international English-language papers on the collaborative governance of environmental and cultural water to inform practice in Canada (Ch. 3). In Chapter 4, I investigated the uptake of environmental and cultural flows in Canadian legislation and assessment and suggested steps for their protection. Moving to Treaty Four, I examined barriers to water regulation (Ch. 5), developed flow-based sustainability criteria for the Qu’Appelle and South Saskatchewan sub-basins (Ch. 6), tested these criteria (Ch. 7), and proposed regional response options (Ch. 8) for the Lake Diefenbaker Irrigation Expansion and Agricultural Water Stewardship Policy (that promotes continued wetland drainage).
Overall, dissertation findings established that, worldwide, communities need to have a greater role in environmental and cultural water policy, planning, and impact assessment (Ch. 3). In Canada, experts detailed a need for water councils to set needs-based rules for environmental and cultural flows maintenance ahead of development (Ch. 4). In Saskatchewan, water protection is challenged because of abstraction and drainage not triggering assessments, impact and project splitting, a lack of regulation, weak effort to meet the duty to consult, and the absence of regional approaches for identifying and managing cumulative effects of abstraction and drainage initiatives (Ch. 5). Collaborative regional governance (Ch. 8) was identified as needed to support progress towards sustainability through restoration of water and land, equity, respect for Treaties, transparency, climate uncertainty, and procedural justice (Ch. 6, Ch. 7). Together, these studies demonstrate the opportunity for more collaborative regional governance and impact assessment of environmental and cultural water in Canada and inform recommendations for future management and study, provided in Chapter 9
Radar Near-Field Sensing For Biomedical Applications
No full textBiomedical sensing technologies are essential for real-time health monitoring and disease management. Among their applications, blood glucose monitoring is of particular importance due to the global prevalence of diabetes that demands early detection and continuous management. Although clinically approved invasive methods exist, they are often inconvenient and unsuitable for continuous monitoring. Despite extensive research, non-invasive glucose monitoring, whether through wearables or smartwatches, remains an unsolved challenge, with no commercially or clinically validated solutions available.
Radar-based biomedical sensing offers a promising non-invasive, continuous monitoring approach with tissue penetration capabilities. However, challenges such as suboptimal antenna design, near-field limitations, air-skin impedance mismatch, and poor depth resolution persist. A key objective in improving radar sensing performance is to maximize the transmitted power density from the radar's transmit (TX) antenna into the target medium while simultaneously enhancing the reflected power received by the receive (RX) antenna. This dual enhancement significantly improves the radar’s signal-to-noise ratio (SNR). Integrating advanced lenses and metasurfaces addresses these limitations, enabling efficient, practical deployment without major redesigns.
This research introduces the development and implementation of novel radar-based methodologies tailored for biomedical sensing applications. Through innovative system design, advanced signal processing, and rigorous experimental validation, the proposed solutions address key challenges in on-body sensing. The first contribution focuses on advanced lens designs, such as dielectric rod arrays and modified gradient-index (GRIN) Luneburg lenses, aimed at enhancing radar-based external health monitoring at 10 GHz.
The second contribution advances metasurface technologies for internal biomarker monitoring, enabling compact, skin-contact wearable systems with enhanced sensitivity and spatial resolution, with a specific emphasis on non-invasive blood glucose detection. Operating in the 58–63 GHz millimeter-wave band, the proposed metasurface-enhanced radar system integrates the BGT60TR13C sensor from Infineon Technologies with a planar, phase-synthesized metasurface for near-field focusing within the skin dermis layer, achieving over 11-fold improvement in SNR by enhancing both transmitted and reflected power. Four progressively objectives are presented, each expanding upon the foundation of the previous stage: single-band, single-focus metasurface, a preliminary design serving as proof of concept; metasurface-enhanced multi-radar fusion for distributed sensing; dual-band, dual-focus metasurface for depth-selective monitoring; and a multi-band, multi-focus non-interleaved metasurface for combined spatial and depth resolution. These innovations have the potential to revolutionize non-invasive, continuous health monitoring
Characterization of Microbial Communities of the Utikuma Region Study Area (Alberta, Canada)
No full textUnderstanding the drivers of bacterial communities and the dynamics of boreal ecosystems is critical for safeguarding water quality and ecosystem resilience in the face of environmental change. This study investigates the interplay between cyanobacterial dynamics and ecohydrologic factors in the Utikuma Region Study Area (URSA) of northern Alberta. Cyanobacteria play a pivotal role in oxygenic photosynthesis and nutrient cycling, yet their unchecked proliferation can lead to harmful algal blooms with significant ecological and economic consequences.
Field sampling was conducted in 34 URSA ponds using a two-phase filtration process designed to capture both larger microbial and picocyanobacterial cells. DNA was extracted and analyzed through 16S rRNA gene sequencing, with taxonomic assignments derived from the curated CyanoSeq 1.3 database and complementary methods. Advanced bioinformatics pipelines provided high-resolution community profiling, while statistical analyses—including redundancy analysis and PERMANOVA—linked microbial diversity patterns to water chemistry parameters (e.g., pH, nutrients, trace metals) and ecohydrologic variables such as hydrologic relief areas, hydrologic units, and wildfire disturbances.
Key findings indicate that environmental factors explain up to 23.9% of the variance in microbial composition based on clr-transformed RDA. Notably, landscape-scale drivers and wildfire history significantly influenced community structure, with their interactions accounting for up to 30.1% of the variance (PERMANOVA). Dominant phyla observed included Pseudomonadota, Bacteroidota, Actinomycetota, Cyanobacteriota, and Verrucomicrobiota, while analysis of 165 cyanobacterial Amplicon Sequence Variants highlighted taxa such as Prochlorococcaceae and Aphanizomenonaceae.
These results, while based on a specific sampling period, provide valuable foundational insights into the relationships between ecohydrologic drivers and microbial community structure for a region previously uncharacterized in this regard. This work sets the stage for further research to refine taxonomic methods and inform targeted water quality management strategies in boreal ecosystems
Governance and Public Engagement from the Perspectives of Antimicrobial Resistance Experts: An Explorative Study
No full textBackground: Antimicrobial resistance (AMR) has long been a threat to medicine as it reduces the efficacy of antimicrobials that once saved millions of lives. AMR is a multifaceted issue that has many drivers and thus, multiple actors need to be involved for an effective solution. Current prescribing practices, non-compliance issues, and even climate change are accelerating the rate at which AMR is occurring, hence current and future plans need to focus on hindering its propagation. AMR is a One Health problem that involves many sectors and in essence a social issue that necessitates proper governance structures across sectors as well as effective public engagement.
Objectives: The main objective of this study was to identify and compare governance and public engagement elements that emerged from Swedish and Malaysian AMR experts’ discussions during two workshops held on September and October 2020 on the effectiveness and sustainability of taxation and Infection Prevention Control measures in tackling AMR in the future. Specifically, the objectives of this study were to: (i) identify and compare governance elements emerging from Sweden and Malaysia, (ii) identify public engagement elements emerging from Sweden and Malaysia, and (iii) identify and compare context-specific governance and public engagement challenges and opportunities in both contexts.
Methods: A secondary data analysis was conducted on pre-existing data collected from 18 AMR experts in Sweden and Malaysia that discussed taxation and infection prevention control measures as effective interventions to tackle AMR in 2030 and 2050. These data were analyzed for governance and public engagement elements using Anderson’s governance framework and the sociocognitive theory, respectively. NVivo software was used to analyze and organize the data based on the governance and public engagement frameworks selected; new elements of governance and public engagement that emerged were also added as necessary.
Results: Swedish and Malaysian AMR experts discussed all 18 of Anderson's governance elements. Swedish and Malaysian AMR experts described governance as needing proper diagnostics, a One Health surveillance system, investment into research and development, lesson learning, and collaboration across industries and countries. Swedish AMR experts discussed all 6 elements of public engagement, whereas Malaysian experts discussed only four. Malaysian experts did not discuss ‘goals’ and ‘sociocultural facilitators.’ While Swedish AMR experts discussed people’s willingness to pay for antibiotic-free products and needing quick fixes, Malaysian AMR experts discussed the issue of wet markets in Southeast Asia. Context-specific opportunities and challenges differed across the two contexts. Two new elements of governance were identified through Swedish AMR experts’ discussions: incentivization of pharmaceutical companies to develop antimicrobials and raising AMR priority among policymakers. No new elements of governance were revealed through Malaysian experts’ discussions. Consistent messaging was a new element of public engagement revealed through Swedish AMR experts' discussions, while two new elements were revealed through Malaysian AMR experts: AMR message delivery and conflict of interest. Interactions were observed within governance elements, public engagement elements, and between the two frameworks.
Conclusion: This study highlighted the multidisciplinary nature of a complex issue like AMR. It is the first to use Anderson’s governance framework to evaluate AMR discussions presented by experts from Sweden and Malaysia and employ the sociocognitive theory, which is often underrepresented in the AMR literature. The discovery of new elements of governance, public engagement, and the overall interactions between the two concepts shows that there is much yet to know about AMR and its driving factors
Quantum programming and synthesis: Internalizing Clifford operations and beyond
No full textClifford operations are a subset of quantum operations used extensively in quantum error correction and classical simulation of quantum circuits.
The first part of the thesis is motivated by the problem of programming with generalized Clifford operations, such as the quantum Fourier transform. We delve into the algebraic complications that arise for systems of even dimension , and we are particularly interested in the case when is a power of . We apply our results in the design of a quantum functional programming language, in which the user does not have to worry about these irrelevant complications.
Later, we consider the problem of compiling circuits over universal gate sets. In particular, we study the problem of multi-qutrit exact synthesis over a variety of gate sets including Clifford gates.
Lastly, we present a framework for defining a symplectic form on an object in a sufficiently structured category, and lay out the theory, generalizing the theory of symplectic forms on a finite dimensional vector space or locally compact abelian group. In the process, we develop new results and perspectives on operations defined on categories
In any way I can
No full textIn any way I can explores memory, longing, and impermanence through photographic and sculptural installations. This body of works embody the paradox of presence and absence within the realms of experience, death, and loss. Key themes include an investigation of the precarity of identity and familial histories, emphasizing how the static, photographic and fugitive image can deteriorate, fade, and transform over time. Within the installation, the concept of home is presented and serves as both physical and metaphysical framework, to process memory and self-formation. Using the gallery as a nonlinear spatial diary, I reimagine personal and collective histories through materialized recollections of objects and places, some of which predate my existence. In this diaristic space, photographs—both personal and discarded—interact with organic, second-hand, and inherited materials, mapping an emotional geography that questions the fallibility of memory. In any way I can acknowledges the fluid boundaries between tangible environments and the internal landscapes they become, reflecting the universal experience of becoming and unbecoming