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The Woman, the Queer, the Monster: Decolonial Approaches to the Other in "Vampire humaniste cherche suicidaire consentant"
Get PDFThis article applies decolonial constructions of queer sexuality and a critical view of the philosophical Other to analyze the woman-vampire in the French-Canadian horror-comedy film "Vampire humaniste cherche suicidaire consentant" (2023). By elaborating on the inherent queerness of the vampire’s status as monster and reading the film’s neutral stance on vampirism, the politic of exclusion central to the horror-genre is critically examined as a product of colonialism, and the film is presented as a decolonial addition to the genre
Advanced High-Temperature Alloys and Oxides: Design, Performance, and Optimization of Complex Concentrated Alloys and Thermally Grown Oxides
No full textThe increasing demands for high-temperature (HT) structural materials in energy, aerospace, and waste-to-energy industries have driven research into advanced alloys capable of withstanding extreme environments. This study investigates the oxidation, hot corrosion resistance, and thermodynamic stability of commercial alloys, complex concentrated alloys (CCAs), and thermally grown complex concentrated oxides (TG-CCOs) for HT applications.
The research begins by evaluating the hot corrosion performance of Fe- and Ni-based commercial alloys in simulated combustion environments, identifying their limitations at 850°C under Na₂SO₄-NaCl salt mixtures. The study then shifts focus to Fe-Cr-Ni multi-principal element alloys (MPEAs), which exhibit improved corrosion resistance at 700–900°C. Element selection plays a pivotal role in optimizing hot corrosion resistance in MPEAs. It is important to avoid using elements with high corrosion activity, such as Mn, and to reduce the relative contents of Fe and Ni. This is essential to control the formation of unprotective corrosion layers and prevent the decomposition of the alloy.
Phase stability and diffusion mechanisms during oxidation of FeCrNi medium entropy alloys (MEAs) are analyzed through experimental observations and density functional theory (DFT) calculations. Key findings include the importance of temperature-dependent transformation from FCC to BCC and Cr diffusion in forming protective oxide layers, enhancing HT oxidation resistance. The study on diffusivities, phase structures, and oxidation behavior in the FeCrNi alloy establishes a strong foundation for advancing HT alloys with enhanced oxidation resistance. The hot corrosion resistance primarily depends on the thermally grown oxide layer (TGO) and the phase stability of the structural base alloy. Therefore, this study also explores the corrosion resistance and structural stability of TG-CCOs on a novel AlCrTiVNi5 alloy. These TG-CCOs demonstrate remarkable thermodynamic stability and corrosion resistance, with a significant structural transition from rock-salt to corundum oxides under HT conditions. Moreover, lattice distortion assessments suggest that these structural changes enhance the durability of the oxides. These findings establish TG-CCOs as promising candidates for next-generation protective coatings.
This comprehensive study addresses critical gaps in materials science by providing insights into the design, performance, and optimization of CCAs and TG-CCOs. The outcomes contribute to advancing HT structural materials, offering significant potential for improving energy efficiency, reducing emissions, and extending the service life of components in extreme environments
Advancements in Pavement Performance Monitoring: A Comprehensive Analysis of Sensor-Based and Model-Driven Assessments
No full textPavements in cold regions endure extreme climatic conditions and fluctuating, often increasing, traffic loads that contribute to various structural failures over time. To extend the lifespan of these pavements and maintain their functionality, continuous monitoring and well-planned maintenance strategies are essential. This thesis presents an integrated approach to pavement performance assessment, utilizing embedded instrumentation to collect critical data on environmental conditions and the stresses and strains induced within the pavement structure. This approach enables professionals to make informed maintenance decisions based on real-time data.
The research is divided into four main sections. The first part provides a literature review on sensor technologies used in pavement instrumentation, highlighting different sensor applications and their significance for accurately analyzing pavement conditions. This review examines a range of case studies that demonstrate how sensors such as Horizontal Asphalt Strain Transducers (HASTs), Vertical Asphalt Strain Transducers (VASTs), Earth Pressure Cells (EPCs), and environmental sensors play a pivotal role in gathering data on temperature, moisture, strain within various pavement layers. The insights drawn from these case studies underline the importance of sensor-based monitoring for effective infrastructure management and maintenance.
The second part of this research focuses on the construction and instrumentation of a test road section built in July 2022 in Edmonton, Alberta, on a high-traffic access road leading to the Edmonton Waste Management Center. This "smart road" test section includes 36 embedded sensors that provide continuous data on pavement conditions, capturing the response to traffic loads through strain measurements and environmental monitoring.
The third part of the study employs both dynamic sensor data and outputs from a Weigh-in-Motion (WIM) system, along with finite element modeling, to provide a comprehensive analysis of pavement performance from July 2023. Findings indicate that the outer wheels of vehicles predominantly influence strain sensors in the middle longitudinal row, validating the need for multiple sensor placements. A comparative analysis between sensor data and finite element model predictions showed differences of 4.3% for the horizontal strain and 22.5% for the vertical strain, underscoring the accuracy and limitations of sensor-based measurements in practical applications.
The final section addresses the critical issue of pavement fatigue life, as repeated traffic loading induces strains and stresses that can lead to cracking, rutting, and other structural deteriorations over time. In this section, a one-year field study was conducted, with data collected from strain transducers and EPCs installed in the instrumented road section. Traffic data was obtained via a WIM system, and environmental data, such as temperature and solar radiation, was sourced from a nearby weather station. Additionally, a Dynamic Modulus (DM) test provided input on the viscoelastic properties of the asphalt concrete layer under different temperatures and frequencies. KENPAVE finite element software was then used to model the pavement’s response to these inputs, with results compared against field measurements. Findings showed general consistency between the predicted and observed data, though discrepancies occurred due to seasonal temperature changes and variable loading conditions. This analysis highlights the potential of combining real-world sensor data with predictive modeling to enhance the accuracy of pavement performance assessments, ultimately contributing to more resilient and sustainable pavement infrastructure.
Overall, this research demonstrates the effectiveness of integrating sensor technology with modeling techniques for the continuous monitoring and assessment of pavement performance in cold climates. The findings offer valuable insights for transportation engineers seeking to design, maintain, and optimize pavement systems that can withstand the demands of both environmental and traffic-induced stresses over time
Relationships between Canadian beef grade and intramuscular collagen characteristics in bovine m. longissimus lumborum
Get PDFConsumers’ decisions to purchase beef are determined by various factors, including meat appearance and anticipated and experienced eating satisfaction. While there are different contributions of each intramuscular component to meat quality, intramuscular connective tissue (IMCT) impacts beef tenderness as “background toughness”. IMCT is primarily composed of the protein collagen, which increases in crosslink complexity as animals age. Youthful animals primarily have immature divalent collagen crosslinks and Ehrlich Chromogen which are temperature labile. However, as animals age, the divalent crosslinks transition into a mature, trivalent crosslink pyridinoline which provides increased stability to the collagen structure throughout muscle. This results in declining collagen heat solubility as well as increased Slice Shear Force (SSF) of cooked meat. For consumers, this is undesirable for beef, as it requires extended cooking periods to allow the collagen to degrade and gelatinize. Current research has reported the impacts of pyridinoline and Ehrlich Chromogen on beef toughness; however, the effects of divalent collagen crosslinks are less understood.
The objective of this study was to evaluate the relationship between beef quality grade, toughness as determined by SSF, and collagen characteristics, specifically collagen solubility and collagen divalent and trivalent crosslink quantification. Longissimus lumborum m. steak samples were randomly collected from beef carcasses (Canada AA, n= 101; Canada AAA, n= 500) and aged for 14 d. After, cooked tenderness was measured using SSF and samples were categorized into tender (SSF=0-19.9 kg), intermediate (SSF=20.0-39.9 kg), and tough (SSF>40.0) subcategories. Collagen heat solubility was measured on a frozen uncooked portion from each sample, and categorized as high or low collagen solubility, and related to collagen divalent and trivalent crosslinks quantified utilizing a novel technique.
Results showed that muscles from Canada AA carcasses had greater soluble collagen and greater mean slice shear force and less insoluble collagen than muscles from Canada AAA carcasses. However, there were no differences due to collagen solubility or tenderness category. Pyridinoline, lysinonorleucine, hydroxylysinonorleucine, 5, 5’-dihydroxylysinonorleucine, and deoxypyridinoline concentrations were unaffected by and unrelated to, respectively, quality grade and collagen solubility percentage. Ehrlich’s Chromogen had a significant difference for collagen solubility percentage with high solubility having greater concentration compared to low solubility. As the longissimus lumborum muscle used in this study is a tender cut of meat located in the loin area resulting in reduced connective tissue, future research should focus on differing locations of muscle and characterization of divalent crosslinks variation with animal age to identify the relationship between collagen crosslink type and beef toughness
How Academic Streaming is failing Black Students in Ontario Schools
No full textThis capstone paper explores academic streaming and how it has historically affected Black students within Ontario secondary schools. This type of streaming occurs when students’ choose a stream or pathway in grade 9, opting for academic, applied or workplace focused courses. The course choices of students at this level have great significance to their academic careers in secondary school and beyond. Historically, Black students in Ontario schools have consistently been overrepresented in lower-level streams (Livingstone, 2017; James & Turner, 2017). This topic will be explored using the Critical Anti-Racist Theory framework (CART) which will center race as the standpoint from which to discuss this issue (Dei & Lordon, 2013). This framework will take into consideration racism, history, power relations and various systems of oppression which will provide a holistic view into the intersecting factors that affect the stream choice and ultimately academic success of Black students in Ontario secondary schools (Dei & Lordon, 2013)
The ER Thioredoxin-Related Transmembrane Protein TMX2 Controls Redox-Mediated Tethering of ER-Mitochondria Contacts (ERMCs)
No full textThioredoxin-related transmembrane proteins (TMXs) of the endoplasmic reticulum (ER) have emerged as key regulators of ER membrane properties. Within the ER lumen, TMXs and other ER redox enzymes determine oxidative conditions that control the formation and function of ER-mitochondria membrane contacts (ERMCs). ERMCs are regions where the outer mitochondrial membrane (OMM) comes into proximity with the ER, typically at a distance of 10 to 80 nm. ERMCs are biochemically known as mitochondria-associated membranes (MAMs), which are involved in multiple intracellular processes, including Ca2+ signalling, lipid transfer, and mitochondrial dynamics. ERMCs exhibit cytoplasmic redox nanodomains derived from ER and mitochondrial reactive oxygen species (ROS), though their mechanistic regulation is not well understood. TMXs are characterized by an N-terminal ER targeting sequence and thioredoxin (TRX)-like domain containing a Cys-Xxx-Xxx-Cys (CXXC) active motif. This work
focuses on TMX2, which has a single cysteine in a conserved SNDC motif, corresponding to an incomplete TRX-like domain. We found that TMX2 mainly localizes to ERMCs, where it uses
its unique cytosolic TRX-like domain to prevent the sulfenylation of OMM proteins such as TOM70. This occurs through a functional interaction with peroxiredoxin-1 (PRDX1). By doing so, TMX2 interferes with the tethering function of TOM70 at ERMCs, thereby affecting ERMCs-involved biological processes, such as ER-mitochondria Ca2+ flux and mitochondrial lipid homeostasis. Furthermore, we demonstrated that TOM70 sulfenylation occurs at cysteine-
206, and the oxidized TOM70 enhances its interaction with IP3R1, an ER Ca2+ release channel. TMX2 participates in preserving the mitochondrial proteome and maintaining the normal functions of the mitochondrial respiratory chain. Additionally, we found that TMX2 has a functional impact on mitochondrial morphology. TMX2 depletion promotes mitochondrial fission, and this effect depends on the single cysteine within its SNDC motif. Recently, TMX2 mutations have been linked to neurodevelopmental disorders with microcephaly, cortical malformations, and spasticity (NEDMCMS). Using cells from NEDMCMS patients with TMX2 variants, we demonstrated that these variants compromise TMX2 functions and mimic the mitochondrial defects observed in its depletion. In a Drosophila in vivo model, glial knockdown of TMX2 ortholog, CG11007 leads to age-dependent motor and seizure-like phenotypes. Together, this doctoral thesis provides important mechanistic insights into NEDMCMS, linking TMX2-mediated ERMC phenotypes to brain development and function