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Quantum pure state transfer
No full textQuantum spin systems carry information in the form of quantum states, and the
propagation of these quantum states is described by a quantum walk. In order to
construct an operational quantum computer, the task of reliably transmitting quantum
states from one part of a quantum computer to another must be accomplished.
Quantum walks are known to be powerful tools in achieving this task.
Pure states are quantum states represented by unit complex vectors. In this
thesis, we use algebraic and combinatorial techniques to develop the theory of perfect
state transfer on pure states in quantum walks, with emphasis on the adjacency and
Laplacian matrices as Hamiltonians of a graph representing a spin network.
We prove basic results about eigenvalue supports, periodicity, and strong cospectrality
on pure states. We investigate a special type of strong cospectrality called
m-strong cospectrality, and show that m-strongly cospectral pure states admit desirable
quantum state transfer properties. Several characterisations of perfect state
transfer are also given, one for general pure states, one for m-strongly pure states,
and another one for real pure states. These characterisations give rise to algebraic
and analytic properties of pure states admitting perfect state transfer. Moreover, we
determine all complete graphs, complete bipartite graphs, cycles, and paths that admit
perfect state transfer between m-strongly pure states. Constructions of infinite
families of graphs admitting perfect state transfer are also given.
We also characterise perfect state transfer between vertex states in joins and blowup
graphs. We determine when the join operation preserves or induces perfect state
transfer in the resulting graph. We also use blow-up graphs to construct new families
of regular graphs with perfect state transfer. We use these two graph operations to
demonstrate that graphs with perfect state transfer can be constructed from graphs
that do not exhibit such a property.
Finally, we investigate perfect state transfer on s-pair states – pure states that
represent entanglement between two vertices. We establish combinatorial and spectral
properties of s-pair states with perfect state transfer, and characterise its existence
in complete graphs, complete bipartite graphs, paths and distance-regular
graphs. Further, we construct infinite families of graphs with s-pair state transfer.October 202
The social ecology of mosasaurs as evidenced by traumatic paleopathologies
No full textHerein I examine a long-standing hypothesis about agonistic social interactions in Mosasauridae, an extinct family of Late Cretaceous marine toxicoferan lizards. Previous studies on mosasaur agonism presented idiosyncratic evidence, which limited behavioral interpretations. To test the hypothesis that mosasaur aggression can be quantitatively studied and better understood through the lens of their closest relatives, I first conducted a review assessing paleopathological evidence for intraspecific agonism in the fossil record. I adapted existing, well-constrained anthropological methods of identifying traumatic paleopathology to create a framework applicable to fossil research. Next, I tested the established framework in a case study using data from prior mosasaur pathology studies and new observations to identify trends, finding that agonism-attributed features are widespread across Mosasauridae. In addition, unhealed features contradict morphological, and orientation trends observed in healed features. When cross-referenced with shark-attributed features, most unhealed confamilial mosasaur bites imply scavenging rather than deadly attacks. Damage attributed to mosasaurs is predominantly antemortem (77%), cranial (81%), and horizontally oriented; damage attributed to sharks is predominantly peri/postmortem (97%), broadly spread across skeletons, and vertically oriented. Finally, I conducted a systemic paleopathological survey (244 specimens, 2209 elements) of North American mosasaurid skull material to determine frequency, morphology, ontogeny, and taxonomic patterns of cranial trauma pathologies with comparison to known behaviors of modern relatives. 119 total lesions are documented (65 elements, 2.9%) across 39 specimens (15.9%). Pathologies are most common on the anterior snout and are commonly parallel to the tooth row. Pathology frequency correlates with size class, with larger specimens showing more features. One-third of marked specimens show features at different healing stages, implying recurrent behaviors. Cranial pathologies are taxonomically widespread, suggesting this behavior is plesiomorphic for Mosasauridae. These pathologies may result from male-male intrasexual aggressive behavior, as seen in extant varanids and snakes, and their onset at 40-60% maximum size may indicate sexual maturity. If this is correct, consistent absence of these pathologies in the largest specimens may be indirect support for reverse sexual size dimorphism in some mosasaurs, sensu modern snakes. Overall, this study provides new insights into the lives of these marine lizards and helps differentiate behaviors.Natural Sciences and Engineering Research Council of Canada for their grant (DG RGPIN 2021-03756) awarded to Kirstin S. Brink (Advisor)
Royal Tyrrell Museum of Palaeontology Cooperating Society's Dr. Malcolm Heaton Student Research ProgramOctober 202
Characterizing drug allergy management among allergists in Canada: a national survey study
No full textBackground: Unverified drug allergy labels are common and associated with significant patient harm, yet infrastructure and testing practices vary across clinical settings in Canada. Objective: To characterize variability in drug allergy management among allergists in Canada and identify setting-specific barriers to drug allergy testing and desensitization. Methods: We developed a peer-reviewed 40-item survey, distributed via the Canadian Society of Allergy and Clinical Immunology, to assess practice patterns, testing modalities, and perceived barriers among allergists. Descriptive statistics and Fisher’s exact test were used to evaluate responses by practice setting. Results: Sixty-six allergists responded (30% estimated response rate), with 48.4% solely practicing in community clinics and 21.9% solely in hospital-based clinics. While 87.9% performed some form of drug allergy testing, hospital-based allergists were significantly more likely to perform intradermal (81.1% vs. 48.7%, p = 0.004) and patch testing (38.2% vs. 8.8%, p = 0.009), as well as non-oral drug challenges (63.6% vs. 20.0%, p = 0.0005). Common barriers included a lack of nursing support and inadequate reimbursement. Conclusion: Drug allergy management practices vary substantially across Canada, with drug allergy testing being more frequently performed by allergists practicing in hospital-based clinics than by those in community-based clinics. Findings support the need for equitable access to testing infrastructure and system-level investments in improving drug allergy testing services
Indigenous pathways to peace: an exploratory study of the conflict resolution and peacebuilding practices of the Kalasha people of Pakistan
No full textThis study explores the peacebuilding practices of the Kalasha people, an Indigenous community residing in the Khyber Pakhtunkhwa province of Pakistan. The study focuses on uncovering peacebuilding practices rooted in cultural codes and oral laws that govern conflict expression and resolution within the community. The study is theoretically situated in the paradigm of critical, emancipatory, and Indigenous peacebuilding.
The main objective of this research was to delve into how the Kalasha people resolve conflicts and uphold a community marked by rare instances of crime and violent conflict. To achieve this objective, the study used a qualitative approach informed by critical and Indigenous research paradigms. Thirty-three participants were recruited using purposive and snowball sampling techniques. Data were generated through in-depth, semi-structured interviews and non-participant observation and analysed using an inductive thematic analysis approach.
The study findings highlight several factors contributing to the peacefulness of the Kalasha society. Peace within the Kalasha community is not just a concept but a dynamic and fundamental principle that shapes its people’s very existence. Their approach to peace extends far beyond the mere absence of violence, reflecting a profound understanding that peace is an ongoing journey and demands unwavering commitment at all levels of society. They employ divinity, peace education, cultural norms, interdependence, non-aggressive conflict resolution processes, vibrant festivals, songs, and stories, as well as the dedicated roles of men and women mediators using traditional peacemaking methods to actively maintain peace. This holistic practice powerfully demonstrates their dedication to nurturing peace within their community and contributes to the rarity of violent conflict, resulting in what can be described as a peaceful society.C. D. HOWE Memorial Foundation Fellowship
In Creative Writing & Oral Cultures
Berdie and Irvin Cohen Award in PACS
University of ManitobaOctober 202
Synthesis and Coordination Chemistry of a Benzannulated Bipyridine: 6,6'-Biphenanthridine
No full textThe synthesis, characterization and coordination chemistry of a doubly -extended bipyridine analog, 6,6'-biphenanthridine (biphe), is presented. The structure of the molecule has been determined in the solid state by X-ray diffraction, showing an angle of 72.6˚ between the phenanthridine planes. The free, uncoordinated organic molecule displays blue fluorescence in solution. It can be singly protonated with strong acids, and the protonated form displays more intense yellow emission. The effect of acid on the excited states is interpreted with the aid of TDDFT calculations. Two Ru(II) coordination complexes, tris(6,6'-biphenanthridine)ruthenium(II) dichloride, [Ru(biphe)¬3]Cl2, and bis(2,2'-bipyridine)(6,6'-biphenanthridine)ruthenium(II) tetraphenylborate, [Ru(bpy)2(biphe)](BPh4)2, are also reported and their structures determined in the solid state by X-ray diffraction. Both complexes display emission at 77 K that is strongly bathochromically shifted by almost 200 nm compared to that of the archetypal 3MLCT emitter [Ru(bpy)3]2+. Such a red-shift is consistent with the more extended conjugation and lower-energy * orbitals associated with the biphe ligand, lowering the energy of the 3MLCT excited state, as revealed by TDDFT calculations. The efficient non-radiative decay that is typical of such low-energy emitters renders the phosphorescence extremely weak and short-lived at ambient temperature and rapid ligand photodissociation also competes with radiative decay, especially in the heteroleptic complex. Electrochemical analysis illustrates the effect of biphe’s stabilized vacant * manifold, with up to multiple reversible reductions evident at much less negative potentials than those observed for [Ru(bpy)3]2+
Reinterpreting Article 33 of the Convention on the Rights of the Child: a case for harm reduction as a rights-based approach to child protection
No full textArticle 33 of the UN Convention on the Rights of the Child (CRC) obligates state parties to take “all appropriate measures” to protect children from illicit drug use. However, the interpretation and implementation of this ever so ambiguous provision has largely focused on punitive and abstinence-based strategies. This is exemplified by the lack of substantive commentary on Article 33 by the Committee on the Rights of the Child, with current discourse and policy development predominantly shaped by bodies whose primary mandate lies outside the realm of children’s rights; UN Commission on Narcotic Drugs (CND), UN Office of Drugs and Crime, and the International Narcotics Control Board.
In view of the foregoing jurisprudential complexities, this study critically examines the potential of reinterpreting Article 33 of the UN Convention on the Rights of the Child through a harm reduction lens to challenge systemic inequalities in current drug policies. It investigates how such a reinterpretation might fulfill states obligations to ensure non-discrimination and equal protection under international human rights law, particularly for BIPOC and unhoused children. The research scrutinizes the stark disparities in treatment between affluent youth engaging in drug use within their confines of privilege and the disproportionate criminalization of marginalized children for similar behaviors.
The central argument posits that current abstinence-only approaches within the human rights paradigm fail to uphold children’s rights to health, protection from harm, and non-discrimination, and proposes harm reduction as a more effective and rights-compliant strategy. Moreover, I contend that, in re-interpreting Article 33 of the CRC to encompass evidence-based harm reduction strategies, state parties as duty bearers may more effectively fulfill their obligations under the CRC while addressing the complex, intersecting vulnerabilities faced by diverse youth populations. In examining how harm reduction approaches can be integrated into the interpretation of Article 33, this study aims to provide a more comprehensive and rights-based framework for addressing substance use among children. One that transcends the pervasive application of a normative single-axis framework, to contribute to a more nuanced understanding of how international human rights law can adapt to evolving public health approaches while adhering to its overarching mandate of best interest and protective intent for children.October 202
Unwinding complexity: reflections on disentanglement
No full textThis thesis explores the material, emotional, and conceptual dimensions of weaving and unweaving as metaphors for navigating diasporic identity, cultural memory, and feminist resistance. Rooted in personal experience as an Iranian immigrant artist, the research positions textile practices—particularly weaving—as both an embodied archive and a radical artistic gesture. Through the integration of natural dyes, Persian motifs, Farsi script, and traditional forms like Boteh Jegheh and Girih, the work challenges the historical marginalization of craft within fine art, reclaiming weaving as a site of meaning-making and political engagement.
Foregrounding the dual metaphors of love and death, the thesis engages with philosophical frameworks from Hannah Arendt, Alain Badiou, and Françoise Dastur to reflect on the emotional textures of displacement and transformation. Weaving becomes a method of care, continuity, and relational connection, while unweaving reveals the symbolic ruptures and absences of migration. Through sculptural installations, community-based weaving performances, and unweaving techniques on saffron-dyed canvas, the practice traces a diasporic cartography shaped by memory, materiality, and metaphor. Ultimately, this research reimagines weaving not only as a formal process but as a feminist act of resistance, a visual language of survival, and a poetics of becoming for the diasporic self.University of Manitoba, School of ArtOctober 202
Mutual empowerment of distributed AI and blockchain
No full textDue to their security, transparency, and decentralized trust model, blockchains have been integrated into a wide range of applications. Distributed and collaborative deep learning approaches, such as Federated Learning and Split Learning, are among the most prominent areas jointly explored with blockchain. This thesis investigates how blockchain mutually empowers distributed learning frameworks—and vice versa—through three novel contributions. First, we propose Proof-of-Collaborative-Learning (PoCL), a blockchain consensus mechanism that replaces energy-intensive mining with productive federated learning tasks, enabling secure, incentive-aligned, and resource-efficient consensus. Second, we advance SplitFed Learning (SFL) by introducing Sharded SFL for improved scalability, and Blockchain-enabled SFL (BSFL), a decentralized variant that uses smart contracts to coordinate shard aggregation and ensure model integrity. Third, we present Blockchain-enabled Personalized Federated Learning (BPFL), a framework that enhances fairness and model ownership by incorporating contribution-based personalization and a tokenized access mechanism, with theoretical convergence guarantees. Through these contributions, this thesis demonstrates how decentralized learning and blockchain can be integrated to improve security, efficiency, and fairness in collaborative AI systems.October 202
The Hilbert functions of families of fat point schemes
No full textWe determine the Hilbert functions of families of fat point schemes supported on special point sets called \textit{partial intersections}. The partial intersection on which we focus is of type and , where . We employ an algorithm known as the \textit{greedy algorithm} to reduce the multiplicities of associated fat point schemes to zero. The algorithm produces a vector that can be used to determine an upper and a lower bound of the Hilbert function of any fat point scheme. For each family that we investigate, the vector is special enough (called \emph{GMS}) that the upper and lower bounds are equal, determining the Hilbert function in each case.October 202