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SAS-PINN: An Enhanced Physics-Informed Neural Network for 2-D Time-Domain Electromagnetic Field Computation of Power Transformer
No full textIn this paper, an enhanced physics-informed neural network (PINN) framework is proposed for accurate time-domain
electromagnetic field computation in power transformers. To address the numerical stiffness and convergence challenges arising from
steep field gradients between ferromagnetic cores, dielectric materials, and multi-layer windings, the high-frequency representation
capability of the SIREN network architecture is leveraged. A novel adaptive collocation point sampling strategy is developed to
dynamically refine spatial-temporal sampling resolution in high-gradient regions, effectively balancing numerical accuracy with
computational efficiency. The proposed framework rigorously embeds Maxwell’s equations and composite boundary conditions into
the loss formulation, establishing a surrogate model for 2D electromagnetic field computation. Numerical results demonstrate a twoorder-
of-magnitude reduction in prediction error compared to vanilla PINNs with random sampling strategy. This breakthrough
enables efficient simulation of time-domain multi-physics fields in complex electromagnetic devices featuring intricate geometries
and multi-material interfaces
Improving Molecular Property Prediction with Degree-Bounded Graph Neural Networks
No full textMolecular property prediction is fundamental to modern drug discovery, materials science, and chemical engineering, where accurate computational methods can significantly accelerate the identification of molecules with desired properties and reduce costly experimental iterations. Graph Neural Networks (GNNs) have emerged as a promising approach for this task, leveraging their ability to naturally represent molecules as graphs where atoms serve as vertices and chemical bonds as edges. However, despite their theoretical expressiveness, current GNN architectures often struggle to perform well in certain tasks, perhaps as they overlook key structural constraints inherent to molecular graphs. In this work, we introduce a novel GNN architecture that explicitly exploits the degree-bounded nature of molecular graphs, where each atom has a physically constrained maximum number of possible bonds. Unlike traditional GNN approaches that rely on simple aggregation functions (such as sum, mean, or max) to provide a fixed-sized vector of inputs to a node (independent of its number of neighbors), our method makes use of degree-bounded properties to capture more nuanced structural patterns. Through comprehensive empirical evaluation on established benchmarks, such as MoleculeNet, we demonstrate that our approach consistently outperforms traditional GNN architectures across various molecular property prediction tasks. Our experiments also explore the need for ordering a node’s neighbors, and then different strategies for producing such ordering. Additionally, our further empirical analysis shows how our architecture mitigates the over-smoothing problem common in deep GNNs, allowing for deeper architectures that can capture more complex molecular properties. Furthermore, our theoretical analysis of the expressivity of the proposed aggregation function highlights its advantages, and investigates the practical limitations of previous GNN aggregation functions
The story of an event and a neighbourhood: Edmonton International Fringe Theatre Festival and Whyte Avenue
No full textIn 1982, Edmonton launched its own Fringe Festival, becoming the first of its kind in Canada. Stretching from Victoria to Montreal, these festivals have become vital spaces for exploring themes of identity, place, and their intersections. The Edmonton International Fringe Theatre Festival, North America's oldest and largest Fringe Festival, is a cornerstone of artistic expression and cultural vibrancy, drawing audiences each August to Edmonton’s Old Strathcona neighbourhood and Whyte Avenue. From the 1960s to the 1980s, Old Strathcona emerged as an epicentre of social resistance to modernist urban development, preserving its distinctive character and shaping Edmonton’s spatial and social trajectory. However, this preservation is only one part of a larger co-evolution. The relationship between the Fringe Festival, Whyte Avenue, and the city of Edmonton is marked by overlapping feedback loops, mutual dependencies, spatial, social, and economic. Each influenced and was influenced by the others in their own processes of identity formation. Edmonton, after early self-organizing efforts, looked to Whyte Avenue and the Fringe Festival to fulfill broader urban ambitions. Whyte Avenue, in turn, developed into a theatre and cultural district in part because of the Fringe Festival’s presence, while the Fringe Festival benefited from and suffered due to the area's changing fortunes, from municipal support to rising costs. This reciprocal evolution reveals a deeper entanglement of place and performance. The ongoing planning and development of Whyte Avenue cannot be understood in isolation from its history with the Fringe Festival and the city, all three in flux and negotiating roles, visibility, and meaning. How has the preservation of Old Strathcona and Whyte Avenue influenced the Fringe Festival’s role in shaping Edmonton’s social and spatial dynamics? In what ways do the interactions between artists, organisers, and audiences at the Fringe Festival reflect broader societal shifts? Today, this vibrant area serves as a dynamic site where community identities are negotiated, and theatre moves beyond its traditional boundaries. Viewing the Fringe Festival solely as an artistic event overlooks its embeddedness in the city’s topography and its participation in a wider co-constitutive process linking cultural practice, social identity, and urban transformation. While the Fringe Festival is undeniably a celebration of the arts, its influence on Whyte Avenue extends far beyond theatre, shaping and being shaped by the neighbourhood through an ongoing, complex, and evolving relationship
Navigating the Semiochemical Landscape: Attraction of Subcortical Beetle Communities to Bark Beetle Pheromones, Fungal and Host Tree Volatiles
No full textSubcortical beetle communities interact with a wide range of semiochemicals released from different sources, including trees, fungi, and bark beetle pheromones. While the attraction of bark beetles, their insect predators, and competitors to bark beetle pheromones is commonly studied, the attraction of these beetle communities to other sources of semiochemicals remains poorly understood. We tested the attraction of bark and wood-boring beetles and their predators to host stress volatiles, fungal volatiles, and a mountain pine beetle (Dendroctonus ponderosae) lure in the field. Host stress volatiles were derived from lodgepole pine (Pinus contorta var. latifolia) trees stressed by three fungal symbionts (Grosmannia clavigera, Ophiostoma montium, and Leptographium longiclavatum) of mountain pine beetle and two common phytopathogens (Atropellis piniphila and Endocronartium harknessii). Our results showed that bark beetles, particularly mountain pine beetles, show a preference for a combination of fungal volatiles, particularly 2-methyl-1-butanol and its lures. Without the addition of lures, 2-methyl-1-butanol was also identified as a key fungal volatile in the attraction of mountain pine beetle competitors from the Cerambycidae and Buprestidae families. Predators in the Elateridae and Staphylinidae families showed attraction to host stress volatiles and the healthy tree volatile profiles. These findings suggest that these semiochemicals warrant further field testing for potential use in monitoring and management of subcortical beetle populations
The Influence of Iron Deficiency on Vitamin A Homeostasis
No full textBackground: Micronutrients support a wide range of physiological processes, and their deficiencies can lead to serious health consequences. Iron deficiency (ID) is the most prevalent micronutrient deficiency worldwide, and young children are particularly susceptible due to the elevated metabolic demands associated with rapid growth and development. As such, it is estimated that approximately 40% of preschool aged children (<5 years old) are affected by ID worldwide. Notably, ID of varying severity has been linked to the dysregulation of vitamin A (VA), another micronutrient that is essential throughout early life. VA deficiency (VAD) also imposes a major burden on global health, affecting an estimated 30% of children under the age of five. Critically, it is well established that both ID and VAD during childhood impair growth and development, resulting in both acute and chronic deleterious sequelae. Aims: While ID and VAD frequently co-occur in early life, little is understood about the influence of ID on VA homeostasis. Previous epidemiological and preclinical studies have reported that ID is associated with reduced circulating VA levels; however, details of this relationship remain poorly understood. As such, the objective of this research was to determine the molecular mechanism of disrupted VA homeostasis caused by ID. Methods: To complete this objective, several rodent models of early-life ID and VAD were used; (1) male and female Sprague-Dawley rats were fed an iron-replete or iron-restricted diet for 6 weeks post-weaning; (2) male and female CD-1 Elite mice were fed either an iron-replete or iron-restricted diet for 11 weeks post-weaning; (3) male C57BL/6 TfrcAlb-Cre and Tfrcfl/fl mice were fed a control diet for 4 weeks post-weaning; and, (4) male and female C57BL/6 mice were fed a
VA-replete or VA-restricted diet for 14 weeks post-weaning. At the conclusion of all dietary intervention periods, animals were euthanized and tissues were collected for comprehensive analysis of iron and VA metabolism. Experimental outcomes included hemoglobin concentrations, tissue retinoid concentrations, hepatic iron and VA-related gene expression, and plasma and tissue VA-related protein expression.
Results: Severe ID was associated with significant disruptions in VA metabolism, including reduced circulating plasma VA, decreased expression of retinol-binding protein 4 (RBP4) and transthyretin (TTR) in the liver, and increased hepatic VA storage. Hepatic RBP4 protein levels were also elevated, whereas hepatic TTR gene and protein expression was significantly decreased. Importantly, these effects were observed exclusively in ID males. Interestingly, circulating VA levels were not changed in animals with moderate or mild ID. Finally, in VAD animals of both sexes, plasma VA and hepatic VA stores were significantly reduced, hepatic RBP4 protein levels were elevated, but hepatic TTR gene and protein expression remained unchanged. Conclusion: These findings demonstrate that in males but not females, severe ID impairs hepatic TTR expression, leading to reduced mobilization of hepatic retinoid stores, lower circulating VA, and reduced delivery of VA to peripheral tissues. In other words, severe ID exerts a sex-specific effect on VA homeostasis, leading to a functional VAD phenotype. Importantly, these observed sexual dimorphisms represent a novel dimension of this micronutrient relationship, and warrants further investigation. Given the widespread co-occurrence of ID and VAD in early childhood and the significant developmental consequences of disrupted vitamin A homeostasis, it is important that more be known about its mechanistic basis in order to develop and implement appropriate prevention and treatment strategies within this vulnerable population
Exploring brain and cell type proteomic changes in progressive multiple sclerosis using mass spectrometry
No full textProgressive multiple sclerosis (PMS) is an autoimmune demyelinating disease of the central nervous system (CNS) in humans. PMS is defined by neuroinflammation and axonal damage with concurrent advancing neurological disability, although the underlying molecular mechanisms remain uncertain. To investigate the molecular basis of PMS, we used mass spectrometry to define proteomic profiles and specific protein changes in matched CNS tissues (cortex, white matter, and demyelinated lesions) from persons with PMS and age/sex-matched other disease controls (ODCs). These studies were validated by analysing proteomes of primary human neural cell types including neurons, astrocytes, microglia, oligodendrocyte progenitor cells (OPCs) and CNS tissues from PMS mouse models. Collagen-containing extracellular matrix (ECM) related proteins, including the annexin, S100, and AHNAK protein families, were significantly enriched in PMS white matter, especially within demyelinated lesions compared to matched ODC tissues. These enriched proteins showed increased abundance in astrocytes and microglia compared to neurons and OPCs. Annexin, S100, and AHNAK family proteins were also increased in the CNS of the cuprizone and experimental autoimmune encephalitis mouse models. These findings highlight the importance of ECM protein induction in CNS glial cells during PMS while also providing new diagnostic and therapeutic options for future investigation
The AurMac deposits: geology and mineralization controls of metasediment-hosted gold deposits in a reduced intrusion-related gold system district
No full textThe AurMac property, located 35 km north of Mayo in central Yukon, includes two metasedimentary-hosted gold deposits: the 6158 koz Au Powerline deposit and the 845 koz Au Airstrip deposit. Gold mineralization occurs as sheeted quartz veins at Powerline and skarn horizons at Airstrip. The property straddles the Robert Service thrust fault, with Powerline hosted in the Late Proterozoic to Cambrian Hyland Group hanging wall, and Airstrip in the Mississippian Sourdough Hill Member of the Keno Hill Quartzite footwall. Host rocks are dominantly siliciclastic metasedimentary rocks and variably calc–silicate–altered calcareous metasedimentary rocks. The only igneous rocks in the property are foliated mafic horizons geochemically similar to regional Cambro-Ordovician magmatic rocks, and a south-dipping, mid-Cretaceous aplite dike at Airstrip. Although a causative intrusion has not been identified, Raman thermometry of carbonaceous material and geophysics suggest that the AurMac deposits lie within the thermal aureole of an intrusion interpreted to be northwest of the deposits. Gold mineralization at AurMac is similar to reduced intrusion-related gold systems, including sheeted veins and skarn, and Ag-Pb-Zn veins on the property shares similarities with veins in the Keno Hill silver district. Gangue minerals associated with mineralization are plastically deformed and suggest deformation likely related with the Tombstone strain zone occurred syn- to post-dating mineralization. Given the proposed magmatic-hydrothermal nature of mineralization at AurMac, this would imply that Cretaceous magmatism at AurMac was syn-kinematic, not necessarily postdating the end of convergence-related deformation. Implications of this study include the potential for undiscovered mineralized intrusions on the AurMac property and bulk-tonnage, sediment-hosted intrusion-related gold systems in the Tombstone Gold Belt, as well as a potential overlap in time between mineralization, deformation, and magmatism in the district
TMW 2025
No full textA collection of papers from the Tailings and Mine Waste 2025 conference, held November 2–5, 2025, in Banff, Canada
Neuroqueering the virtual: Disruptive digital storytelling for radically reimagined worlds
No full textAs an emerging storytelling medium, Virtual Reality (VR) facilitates imaginative exploration in ways that are kin to books, video games, and our daydreams. These experiences invite us to wander and explore the unknown, sparking interest and inviting us to dream of impossible worlds. VR is often associated with the language of "transformation," describing its ability to simulate experiences that force proximity with biases and its potential to trigger an expansion of perspective. And yet, the persistent bias of Cartesian mind/body dualism weaves its way from technology discourse, into that of VR. While mind/body dualism has been debunked in favour of more non-binary perspectives, the Enlightenment-era ideal hides within narratives of disembodiment that position technology as our saviours from the burden of the body and the physical realm. Repackaged for our era as "technoableism," "technochauvinism," and "neoliberal futurity", these narratives carry the tradition of Cartesian dualism, reinforcing assimilationist narratives, and placing the burden on individuals to change who they are rather than meaningfully engaging with the politics, history, and culture of marginalized identity. The body (and by extension, disability and marginalized identity) continue to be framed as something to escape from, and with the aid of technology, can transform us into something that better aligns with capitalist neoliberal hegemony: the dominance of a neoliberal ideology within a capitalist system that shapes not only politics and economics, but the social as well. In defiance, projects created by and for marginalized communities resist these frameworks by centering identity, interdependence, and wholeness. Through hacking, DIY, modding, and direct action, disabled and other marginalized communities have long engaged in forcing access and making friction, existing fully embodied within and between the virtual and physical bodymind.
By thinking differently about the body and mind, we dissolve binaries and remember that true transformation comes not from escaping the marginalized body, but from reimagining technology as a partner in liberation. Escape becomes reframed when we look at the virtual differently—when it is deconstructed and entwined with the processes of leaning into the traits we are marginalized for. When it is neuroqueered. Instead of fleeing the body, leaning-in to virtual embodiment becomes an act of resistance. Under these contexts escape becomes a vital part of imaginative and creative well-being. Escape in these contexts is more than simply avoiding the confines of colonial, gendered, and neuro-normative expectations that exist in the physical realm but is a vital part of imaginative and creative well-being. The narratives of disembodiment lose some of their power when the stories we repeat lean into the aspects of identity that marginalized people are pressured to feel ashamed of. As such, virtual realms become a pocket of refuge; a space where identity and sense of self can be explored in relation to community connections, developed through shared interests and desires to wander, explore, and learn. The worlds that individuals and communities build through story are bound to their identities, and VR is not merely a tool to enhance or reduce this identity, but a kin technology that invites us to explore it in flux