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Twilight of Discovery: An Exhausting but Rewarding Journey in the Prairies
Get PDFThis image captures the balance between dedication and nature’s beauty, showing both the challenges and rewards of field research. The setting sun over the grassland mirrors the natural cycles I study—how grassland management affects the nitrogen cycle and how these findings can help reduce greenhouse gas emissions by optimizing nutrient flows and improving soil health. In this quiet yet powerful moment, I feel a deep connection between my research and the landscape, reminding me of the importance of understanding climate change and promoting sustainable land use—this is why we do what we do
Organometallic Catalysts for the Valorization of Renewable Resources: From Biomass to Sustainable Chemicals.
No full textThe transition from fossil-based feedstocks to renewable resources is critical for achieving a sustainable chemical industry. This work explores the pivotal role of organometallic catalysts in valorizing biomass, CO₂, and plastic waste into value-added chemicals and fuels. We highlight advances in catalyst design, including water-tolerant metal oxides (TiO₂/ZrO₂) for selective dehydration of biomass-derived sugars to 5-hydroxymethylfurfural (5-HMF), bimetallic systems enabling cascade reactions for lignin depolymerization, and metal-organic framework (MOF)-supported catalysts for efficient CO₂ hydrogenation under mild conditions. Innovations in flow chemistry are demonstrated to enhance the safety and scalability of reactive organometallic intermediates, while hybrid systems integrating enzymatic and metal catalysis streamline multi-step conversions, such as CO₂-to-methanol pathways. Emphasis is placed on sustainability through the use of earth-abundant metals (Fe, Mn, Ni) and green solvents (e.g., deep eutectic solvents), reducing reliance on rare or toxic materials. Case studies on Fe–N–C catalysts (95% CO selectivity from CO₂) and Mn-catalyzed ketone reductions illustrate the potential for cost-effective, scalable processes. Challenges in industrial integration, such as catalyst stability and reactor design, are critically evaluated alongside emerging solutions like machine learning-driven catalyst optimization. By bridging fundamental organometallic chemistry with green engineering principles, this work provides a roadmap for developing circular systems that convert waste carbon streams—biomass, CO₂, and plastics—into sustainable chemicals, advancing the vision of a fossil-free future
Thoroughfare to the Rhine: Road-Building in France’s Northeastern Borderlands, 1629-1661
No full textAmong numerous treaties that were signed between the Kingdom of France and its neighboring
states during the early modern period, the Treaty of Vincennes (1661) was an unusual type of
land-grabbing. French ministers proposed to create a broad thoroughfare through the Duchy of
Lorraine, which would connect the eastern part of mainland France with its territorial holdings
scattered across Lorraine and Alsace. By examining archival documents, treaties, and diplomatic
papers, this thesis inquires into France’s effort to build a road at the state’s periphery in the
geopolitical context of the seventeenth century.
Early modern borderlands, often characterized by disputed claims over sovereignty and
the lack of clearly-defined boundaries, were porous and sophisticated spaces. Such conditions
could be observed in the Duchy of Lorraine, a small state situated between France and the Holy
Roman Empire. Its domain had been riddled by numerous French exclaves before the Thirty
Years War. As France expanded eastward rapidly during the Thirty Years War, the fate of
Lorraine was redefined by France’s occupation and strategic concerns. French ministers in Îlede-France were looking for a passage that would string France’s scattered exclaves together with
its mainland, and Lorrain lands became the ideal location for the passage. The Duchy’s spatial
identity, which had been more associated with Luxembourg and the Netherlands due to the
Spanish Road of the sixteenth century and medieval historical heritage, shifted to a west-east
oriented one that was more associated with Alsace when the French thoroughfare came into
being
GrEX-Detailed Description
No full textAn introduction to the elements of the detailed description in IG (Insight Grant) and IDG (Insight Development Grant) applications and strategies for fulfilling the evaluation criteria
ABO-A antibody induction in mice is T cell-dependent, estrogen-independent, and modulated by CD22
No full textABO antibodies pose barriers in transplantation but remain poorly studied. We investigated anti-A natural antibodies (nAbs) and induced antibodies (iAbs) in wild-type (WT), CD19KO, and CD22KO mice in the context of major histocompatibility complex-syngeneic or major histocompatibility complex-allogeneic stimulation by ABO-A blood cell membranes (BCM) from A-transgenic mice, or xenogeneic human (Hu-A) BCM. CD19KO mice failed to produce anti-A nAbs and iAbs. Syngeneic A-transgenic-BCM failed to stimulate anti-A iAbs in WT mice, in contrast to allogeneic A-transgenic-BCM and xenogeneic Hu-A-BCM. Hu-ABCM failed to stimulate anti-A iAbs in CD4-T cell-depleted or CD4KO mice, reversed with CD4-T cell reconstitution. Although anti-A nAbs were absent in estrogen-receptor-α-deficient mice, anti-A iAbs were easily stimulated. Anti-A nAbs were higher in CD22KO than in WT mice, with pubertal females producing higher levels than males. Anti-A iAbs were stimulated in CD22KO mice by syngeneic A-transgenic-BCM or by Hu-A-BCM after CD4T cell depletion. We conclude that anti-A nAbs and iAbs are produced by B1a-cells. In WT mice, stimulation of anti-A iAbs requires exposure to nonself A-antigen together with foreign proteins and is T cell dependent. Without CD22-mediated inhibition, anti-A iAb stimulation does not require foreign protein and is T cell-independent. Anti-A iAbs are estrogenindependent, whereas anti-A nAbs are estrogen-dependent and could be elicited by estrogen in males
Impacts of the Enhanced Train Control (ETC) System on Train Operators in Canadian Railways
Get PDFCanada's rail transportation system is a vital part of the economy, ensuring the efficient movement of goods and passengers. However, maintaining safety and efficiency remains a challenge, as the system relies on human operators, making it susceptible to human errors. The Transportation Safety Board of Canada (TSB) reported an average of 35 missed signal incidents per year between 2004 and 2021, underscoring the associated risks. To enhance railway safety, the TSB and the 2018 Railway Safety Act Review Panel recommended implementing a train control system similar to Positive Train Control (PTC) in the U.S., the European Train Control System (ETCS), and the Chinese Train Control System (CTCS). Transport Canada is now developing a vision for Enhanced Train Control (ETC), though it is not yet federally regulated. A Notice of Intent in the Canada Gazette, Part I, outlines a risk-prioritization approach for ETC’s implementation.
The introduction of train control systems, however, raises concerns about the potential for suboptimal workload levels for train operators, which could degrade both operator and system performance. As a result, mental workload assessments must be integrated into system design. While workload models have been widely applied in aviation and nuclear power fields, their use in railway operations — primarily through analytical methods —remains limited. Moreover, existing studies have mainly focused on static mental workload predictions, neglecting the dynamic cognitive demands that train operators face throughout a journey.
This research explores vulnerabilities in train control systems by examining their impact on train operators' mental workload within Canadian Railways. To achieve this, it begins with a review of systematic accident analysis methods, such as the Human Factors Analysis and Classification System (HFACS) and Functional Resonance Analysis Method (FRAM), establishing a systemic approach to evaluating complex train control systems and gaining a deeper understanding of accident dynamics in railways. Subsequently, data on Passing a Stop Signal (PASS) occurrences in Canadian railways, along with weather and geospatial information, were collected, integrated, and analyzed using XGBoost and SHAP machine learning methods. A binary classification model was developed to predict PASS occurrences based on relevant features, while SHAP analysis identified and ranked key non-human contributing factors, assessing their collective impact on missed signals. The findings indicate that track geometry, environmental conditions, and operational factors significantly increase the risk of PASS occurrences in freight trains on Canadian mainlines. Specifically, sharp track curvatures before signals, downhill gradients, low temperatures, high humidity, and low atmospheric pressure were found to be major contributing factors. These elements interact in complex, non-linear ways, affecting signal visibility, stopping distances, and brake performance, ultimately increasing the likelihood of passing stop signals. Comparing the XGBoost model with Logistic Regression highlighted XGBoost’s superior ability to capture these intricate non-linear interactions, reinforcing its effectiveness in modelling complex dependencies. These insights guided the development of safety measures to mitigate PASS incidents and contributed to refining workload measurement through human performance shaping factors. The core of this thesis introduces a hybrid workload measurement method that integrates VACP analysis, fuzzy set theory, and SPAR-H to enhance the traditional VACP method and assess workload across various train control automation levels and real-world settings. Applied across Canadian rail routes under various train control systems and operational conditions, the model revealed that automation does not always reduce mental workload. Compared to highly automated systems, low and Intermediate levels of automation were found to increase workload, particularly when compounded by challenging track and weather conditions. Workload also varies along routes based on environmental, operational, and infrastructural factors; the lower the automation level, the more external conditions impact operators. Based on the findings, safety recommendations were provided, including human factors requirements, system integration, alarm management, and training programs.
This research enhances our understanding of the complex relationship between train control systems, contextual factors, and train operators' mental workload. It introduces a novel analytical mental workload assessment methodology, establishes a baseline for evaluating ETC’s impact on operators, promotes a common framework among stakeholders, and expands the field's knowledge. These findings benefit safety professionals, policymakers, and regulators by supporting the development of evidence-based policies and proactive safety measures for train control implementation
Leveraging Hydride-Terminated Silicon Nanoparticles for the Deposition of Noble Metals and Noble Metal High Entropy Alloys
Get PDFThis thesis discusses an emerging method of modifying group 14 nanomaterials through the deposition of metals on their surface, narrowing in on silicon nanoparticles (SiNPs) in particular. The primary aim of the work presented was to probe the reducing potential of the Si-H bond on the surface of SiNPs, specifically for the deposition of noble metals. An eventual goal was to develop a facile method of synthesizing high entropy alloys (HEAs), a material particularly valued for catalytic applications. First, a monometallic system was explored wherein a rapid, straightforward, solution-based method was used to deposit metal nanoparticles onto the SiNP surface. The influence of the molar ratio of metal to silicon on the reduction of the metals was probed. Furthermore, the role of the SiNP size in the reduction of the metals was also explored. Although the size of SiNP impacted the reduction of some metals, namely Pt, the molar ratio of metal to silicon did not appear to alter the morphology of the materials significantly. The work completed in Chapter 3 expanded upon the methods described in Chapter 2 to deposit AgAuPdPtCu HEAs onto SiNPs. Once again, the role of the SiNP size in the formation of the HEAs was investigated, and it was observed that syntheses involving 3 nm SiNPs were ineffective compared to those involving 9 and 20 nm SiNPs. Furthermore, a method for purifying the HEAs using a HCl acid wash was reported
A Decolonial Poetics of Language: Indigenous Women's Translingual Poetry as Resurgence and Revitalization
No full textThis dissertation examines how Indigenous women poets navigate the complex multilingual landscape in Canada shaped by the attempted erasure of Indigenous languages and the imposition of English and French. Through translingual poetry, they harness both Indigenous and colonial languages to advance Indigenous resurgence and decolonial ways of being in the world. Drawing on author interviews with Tenille Campbell and Naomi McIlwraith and close reading selected poems, I argue that Indigenous women’s translingual poetry confronts settler monolingualism, challenges colonial linguistic hierarchies, portrays and enacts linguistic constellations, and promotes vital paradigms to preserve, teach, and value Indigenous languages.
Chapter 1 offers the first in-depth analysis of multi- and translingual approaches in Indigenous literary studies of its kind, demonstrating specifically how Indigenous literatures written primarily in French contribute to these conversations. Analyzing linguistic constellations in translingual poems and conceiving of Indigenous literary studies along such constellations, this dissertation moves beyond bridging the gap between two fields of study (in French and English) to affirm a heterogeneous conception of language politics in Indigenous literatures and to lay bare and grapple with zones of linguistic tension. Chapter 2 demonstrates how Indigenous women poets manipulate and reinvent colonial languages to contest stereotypes, disrupt linguistic hierarchies, and sustain Indigenous concepts of kinship through transknowledging. I thus foreground translingualism from Indigenous perspectives with Indigenous women’s poetry. Chapter 3 unpacks the previously unexplored relationship between language and the erotic in Indigenous women’s erotic poetry, showcasing a resurgence of Indigenous erotics rooted in Indigenous languages. At the intersection of language and the erotic, these poems dismantle the current status quo of sexual hierarchies in Canada and affirm and practice other ways of sexually relating to one another that are culturally distinct and embedded in Indigenous joy, traditions, representations, and languages. Chapter 4 highlights the power of poetry in language revitalization, showing how “poems-as-language-lessons,” videopoems, and intergenerational literary practices create accessible tools for teaching, preserving, and transmitting Indigenous languages. The poets explored here demonstrate how poetry contributes to documenting and preserving the language, and, more importantly, foreground how their creative practices affirm Indigenous languages as vital living organisms, showcasing that Indigenous communities have always relied on storytelling and poetry to learn language.
By analyzing Indigenous women’s translingual poetry through a decolonial lens, this research emphasizes the tangible, transformative impact of Indigenous women’s poetry in Indigenous language revitalization and Indigenous resurgence. These poets assert the tremendous potential of language(s) as both a form of resistance and a vehicle for revitalization and they highlight how Indigenous languages serve as powerful tools for cultural survival, affirmation, resurgence, and thriving among Indigenous communities