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The effects of extracorporeal shockwave therapy on osteoporotic changes in a pre-clinical model
(2026) Wright, Ashley; Sanzo, Paolo; Lees, Simon; Zerpa, Carlos
Introduction Osteoporosis (OP) is a musculoskeletal disease that is defined by reduction in bone porosity, leading to increased risk and prevalence of falls and fractures. Extracorporeal shockwave therapy (ECSWT) has been reported to assist in tissue regeneration and osteogenesis by mechanotransduction. Evidence from prior studies demonstrated that ECSWT facilitated healing in non-unionized and stress fractures, supporting its potential utility as a treatment modality for OP. Bone-specific alkaline phosphatase (BAP) and osteocalcin (OCN) are blood biomarkers that are secreted by bone formation cells. These biomarkers may be effective as a screening tool to measure osteoporotic changes, as dual x-ray absorptiometry is unavailable in remote and rural regions in Canada, or during space travel. Therefore, the purpose of the study was to examine the effects of ECSWT on osteoporotic changes evident on bone microarchitecture computed tomography imaging and blood biomarkers using a pre-clinical model. Methodology The 32 rats in the study were divided into two conditions (ovariectomy and sham surgery) and two treatments (ECSWT and placebo treatment). The treatment groups received five shockwave treatments, once weekly to the right femur (1,000 shockwaves, energy flux density 0.33 mJ/mm2, at 3 Hz). 1 week after the final treatment, blood was extracted, the rats were exsanguinated, and right femur dissected for analysis. The blood biomarkers were analyzed using an enzyme linked immunosorbent assay and femora were examined by computed tomography imaging. A two-way, independent measures analysis of variance was used to analyze changes in blood biomarkers and bone microarchitecture. Results There was a nonsignificant main effect on condition (OVX and sham) and treatment (ECSWT and placebo) on central 10% of bone mineral density (BMD), with a small effect size. There was a statistically significant simple main effect in BMD for 80% of the right femoral diaphysis between treatment groups (ECSWT and placebo; F(1, 28)=7.84, p=.009, η²=.219) with a large effect size. There was a statistically significant main effect in medial cortical bone thickness between condition (OVX and sham surgery; F(1,28)=6.17, p=.019, η²=.180) with a large effect size. There was a statistically significant main effect in lateral cortical bone thickness between condition (OVX and sham surgery; F(1,28)=6.17, p=.019, η²=.180) with a large effect size. There was a nonsignificant main effect on condition (OVX and sham) and treatment (ECSWT and placebo) on anterior cortical bone thickness, with a small effect size. There was a nonsignificant main effect on condition (OVX and sham surgery) and treatment (ECSWT and placebo) on posterior cortical bone thickness, with a small effect size. There was a statistically significant main effect between OVX and sham surgery condition in mediolateral trabecular bone thickness, F(1,28)=12.978, p=.001, η²=.317) with a large effect size. There was a nonsignificant interaction or main effect between OVX and sham surgery condition in anteroposterior trabecular bone thickness, with a small effect size. There was a nonsignificant interaction or main effect between OVX and sham surgery condition in BAP concentration, with a small effect size. There was a statistically significant main effect between OVX and sham surgery condition in OCN concentration (F(1,28)=11.278, p=.002, η2 =.287) with a large effect size. Conclusion ECSWT treatment resulted in nonsignificant changes in cortical bone thickness, trabecular bone thickness, BMD, or biomarker concentrations of OCN and BAP under these experimental conditions. BMD did not decrease as expected from the OVX surgery, and ECSWT did not cause any alteration in bone microarchitecture. However, the measurements used in the present study may not show a comprehensive analysis of trabecular and cortical microarchitecture as the study only assessed trabecular and cortical bone thickness. ECSWT treatment created nonsignificant changes in blood biomarkers. OCN concentration increased in the OVX group when compared to the sham surgery group, suggesting altered bone remodeling following estrogen deficiency. BAP concentration was not significantly altered by OVX. OCN or BAP alone do not reflect OP changes but may be used as an adjunct assessment of altered osteoblast activity. Future studies should consider assessing additional microarchitecture parameters such as bone volume fraction, trabecular number, trabecular separation, and structural model index, using a repeated measures study design comprehensive and comparative analysis of bone microarchitecture.
Bridging gaps in mental health crisis care: a RE-AIM evaluation of the Superior North Specialized Treatment and Alternative Response (STAR) team in Northwestern Ontario
(2026) Miller, Brianna; Sinden, Kathryn; Klarner-Read, Taryn; Greenaway, Jim; McAllister, Liberty
BACKGROUND: Northwestern Ontario (NWO) faces a mental health crisis underscored by underfunding, limited services, overreliance on emergency departments (ED), and provider burnout. Superior North Specialized Treatment and Alternative Response (STAR) is a mobile mental health crisis response team (CRT) being piloted in Thunder Bay, Ontario that includes paramedics, Crisis Response workers and Indigenous health associates to ensure culturally appropriate and timely care. STAR co-responds to EMS activations for mental crisis calls and provides an alternate, culturally appropriate pathway to care towards reducing ED burden. As STAR is in its pilot phase, metrics associated with impact have been identified towards determining potential upscale. OBJECTIVE: To determine the utility and impact of STAR on reduced burden on ED admissions and other pre-determined key performance metrics using the RE-AIM theoretical framework. The RE-AIM framework (Reach, Effectiveness, Adoption, Implementation, and Maintenance), is a robust tool for evaluating effectiveness of community-based initiatives such as STAR. METHOD: Field data from (April 2025-August 2026) on, call details, disposition (patient outcome at scene), and connection choices (post-response referral options), were analysed using descriptive statistics guided by the RE-AIM framework to access Reach (proportion of EMS calls resulting in STAR activation) and Effectiveness (ED/Hospital diversion rate). Adoption and Implementation were assessed qualitatively through thematic analysis of STAR team meeting minutes from (July 2024-August 2026), guided by RE-AIMs Adoption construct and Implementation’s fidelity and adaptation sub-constructs. RESULTS: Over 17-months, STAR responded to 135 Mental Health and/or Addictions (MHA) calls, with the proportion of SNEMS calls resulting in a STAR activation peaking at 0.60% before declining to 0.08% by the final quarter. Under half (46%) of calls resulted in ED/Hospital transport. Thematic analysis showed meaningful Adoption at the community and setting level, with engagement and activations increasing over time. Implementation maintained fidelity despite adaptations, though staffing constraints limited program availability over the evaluation period. IMPLICATIONS: First responders are reacting to a critical mental health burden in Thunder Bay, Ontario. From the results of the evaluation using the RE-AIM framework, STAR demonstrated strong utility and impact in reducing burden on the ED through supporting individuals who are in mental health crisis in accessing appropriate community-based care.
Effects of drought severity on physiological and morphological responses to future climate in jack pine (Pinus banksiana)
(2026) Chen, Mengyu; Dang, Qing-Lai
Climate change is expected to expose boreal trees to higher atmospheric CO₂, warmer temperatures, and more frequent drought. This study examined how drought severity and future climate affected jack pine (Pinus banksiana) seedlings. Seedlings were grown for eight weeks under current climate conditions (600 μmol mol⁻¹ CO₂ and current temperature) or future climate conditions (1000 μmol mol⁻¹ CO₂ and current temperature +4 °C) and 3 soil moisture conditions: control, moderate drought, and severe drought. Foliar gas exchange was measured under 600 μmol mol⁻¹ CO₂ for the current climate treatment and both 600 and 1000 μmol mol⁻¹ CO₂ for the future climate treatment in the early, middle, and late stages of the drought treatment. Photosynthetic CO₂-response curves were measured to estimate Vcmax, Jmax, and Rd. Seedling height, root collar diameter, and biomass were measured after the completion of all gas exchange measurements. It was found that Vcmax and Jmax were significantly affected interactively by drought and climate treatments, while Rd was not significantly affected by either treatment. The future climate conditions resulted in downregulations in Vcmax and Jmax in the control and severe drought treatment. Under the moderate drought treatment, however, Vcmax was higher under the future climate while Jmax did not show a significant response to climate treatment. The net photosynthetic rate of the seedlings in the future climate treatment measured at 600 μmol mol⁻¹ CO₂ was significantly lower than the corresponding measurement in the current climate treatment in the moderate and severe drought, another indication of photosynthetic downregulation. When measured at the corresponding treatment CO₂, the stomatal conductance and transpiration were significantly lower, but intrinsic water-use efficiency was significantly higher, in the seedlings in the future climate treatment, especially under moderate and severe drought. Drought and climate treatments had no significant overall effects on biomass or morphological traits. Under future climate conditions, seedlings tended to allocate more biomass to leaves and showed a trend toward greater height. Moderate drought tended to shift biomass allocation from aboveground to belowground tissues, whereas severe drought showed a stronger trend toward reduced seedling size and biomass accumulation. Overall, these results indicate that future climate conditions may improve water-use efficiency but cause photosynthetic downregulation and shifts in biomass allocation and accumulation in jack pine.
Graph attention enhanced transformer network: an investigation into day-ahead electricity demand forecasting
(2026) Tsang, Jimmy; Akilan, Thangarajah; Deng, Yong; Ameli, Amir; Zhou, Yushi
The evolution of modern power grids, also known as smart grids, along with distributed renewable power generation and demand-side management strategies, has increased variability in both electricity supply and consumption patterns. As power generation systems transition to smart grids, accurate day-ahead load forecasting has become critical for ensuring grid stability, operational efficiency, and cost-effective energy management under growing electricity demand. Traditional load forecasting approaches often struggle to model the nonlinear and temporal dependencies arising from dynamic weather conditions, shifting consumer behaviour, and increasingly diverse generation portfolios. This thesis proposes a novel approach based on the Temporal Fusion Transformer (TFT) architecture integrated with a Gated Attention Network (GAT) to analyze and predict electricity demand in Ontario. TFT models effectively identify the importance of individual features, but they fail to capture the direct interaction between pairs of features. The integration of a GAT allows the model to overcome this limitation by learning cross-feature relationships adaptively. The model leverages attention mechanisms, interpretable temporal dynamics and inter-feature representations to improve forecasting accuracy and provide insights into key influencing factors. The proposed model, trained on the Independent Electricity System Operator (IESO) dataset, demonstrates its effectiveness in handling the complexities of modern energy systems by achieving an MAPE of 2.92% and 2.18% on Ontario and market demand forecasting, respectively. Further evaluations on the ENTSOE, AEP, and ELIA datasets demonstrate state-of-the-art (SOTA) or near- SOTA performance, achieving an MAPE of 1.77%, 3.05%, and 2.45%, respectively, while validating model generalizability. The contribution of this thesis highlights the importance of capturing inter-feature and temporal dependencies in the field of day-ahead forecasting for smart grids.
Phase-field fracture modeling and energy-based stability analysis of cemented paste backfill
(2026) Nassir, Navid; Cui, Liang; Lu, Gongda; Bai, Hao; Gong, Yanglin; Deng, Jian
Cemented paste backfill is widely used in underground mining to provide ground support and enable the sustainable disposal of mine tailings. As mining operations encounter increasingly complex stope geometries, the fracture behaviour and stability of exposed CPB structures become critical concerns. Conventional stability analyses generally rely on strength-based elastoplastic models that cannot explicitly represent the initiation, propagation, and coalescence of cracks governing the quasi-brittle failure of CPB. They also rarely account for the continuous evolution of fracture properties caused by cement hydration. This dissertation therefore develops two hydration-dependent phase-field fracture models and an energy-based method for assessing the stability of CPB structures. First, an evolutive phase-field model is developed for tensile fracture by linking cement hydration and binder content to the elastic modulus and tensile fracture resistance of CPB. The model is validated against direct tensile, split-tensile, and semi-circular bending tests conducted at different curing ages and binder contents. The results demonstrate its ability to reproduce tensile crack initiation and propagation, load-displacement responses, and the transition from diffuse early-age damage to increasingly localized fracture with continued hydration. Second, a phase-field model is developed for mixed-mode fracture by decomposing the crack-driving energy into tensile and shear components and introducing distinct tensile and shear critical energy release rates. Experimental tests on single- and double-notched specimens, together with additional tensile and mixed-mode validation cases, demonstrate that the model captures crack initiation, propagation, interaction, and coalescence under complex loading conditions. Based on the proposed mixed-mode model, an Energy Limitation Method is developed for three-dimensional, field-scale stability assessment. The method progressively reduces the tensile and shear fracture resistance until unstable, through-going crack propagation occurs, thereby defining an energy-based stability index. Increasing cement content from 4.5% to 8% increased the stability index from 1.6 to 4.0, while increasing curing time from 28 to 120 days increased it from 1.75 to 2.65. In contrast, increasing backfill height from 30 to 60 m reduced the index from 5.35 to 1.25. Overall, the developed framework integrates hydration-dependent tensile and mixed-mode fracture modeling with energy-based stability assessment, providing a physically consistent approach for investigating crack-dominated failure and supporting the design of CPB structures.