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Alkali silica reaction – the mechanism leading to concrete deterioration
Get PDFThe alkali-silica-reaction (ASR) leads to severe deterioration of concrete structures worldwide. The general principle of the reaction is known. However, the mechanism generating pressure and cracking is still debated. The mechanism commonly presented is water uptake of the ASR products that leads to swelling and pressure. In addition to hygric swelling, osmotic pressure has been also attributed for aggregate cracking and concrete expansion. Crystallization pressure is seldom associated with ASR in spite of the fact that it is an accepted mechanism for other types of damage in building materials. This paper reviews and discusses the different mechanisms considered for concrete deterioration induced by ASR. The reaction sequence and the composition of the ASR products are presented as well, because they are the basis for the discussion on the mechanism of pressure generation.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Numerical Analysis on MHD Heat Transfer of Casson Hybrid Nanofluid (Cu-Al2O3/H2O) flow across an Inclined Moving Plate in presence of Radiation
Get PDFThe ability of hybrid nanomaterials to enhance heat transmission has attracted many academics to study the working fluid. This work examines the impressions of radiation efficiency on the convective Casson flow of hybrid Nano liquid across an angled moving plate with a magnetic impression using a mathematical solution. The main aim of this study is to increase the thermal efficiency of the fluid by using different categories of Cu and Al2O3 nanoparticles are combined with the base fluid water. A non-linear partial differential equation system is created while keeping in mind some reasonable presumptions. Using the similarity transformation, the partial differential equations are changed into non-linear ordinary differential equations. And it is then mathematically simplified with the bvp4c technique. Consequences of an exclusivity group of unique impacts on motion characteristics, shear stress, thermal field impressions, and heat transport are described clearly. The motion rised with increasing Casson fluid for stretching and shrinking surfaces. For radiation impression, an energy upsurge profile is visible. With an inclined plate, the shear rate decreases, and the buoyancy impression causes it to rise. This work provides new information about the behavior of heat plumes under magnetic fields, thermal radiation and flow, and has potential applications in enhancing cooling systems in industrial applications, modelling of oil reservoirs and nuclear waste storage. Nanoparticles are used for cooling processors, cancer therapy, medicine, metal strips, automobile engines, welding equipment, fusion reactions, chemical reactions, and for cooling heat exchange mechanisms in various engineering devices due to their superior thermo physical properties.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Factors Affecting Psychosocial Distress in Adolescents and Young Adults with Cancer: BRIGHTLIGHT Cross-Sectional and Longitudinal Cohort Study Results
Get PDFBackground/Objectives: AYAs face unique psychosocial challenges compared to younger children and older adults. Little published data exists about symptoms of psychological distress in AYAs, particularly in large cohorts over time. This study aimed to (1) explore relationships between distress and variables known to impact mental health, (2) examine distress over time, and (3) consult with a patient and public involvement group (Young Advisory Panel, YAP) to contextualize the results. Methods: Secondary data analyses were conducted from a multicentre longitudinal cohort study, which recruited 830 participants aged 13–24 years newly diagnosed with different cancers. The mean age was 20.1 (SD 3.3) and 45% were female. Bespoke surveys, including a validated measure of psychosocial distress, were administered five times over 3 years following diagnosis. Participatory workshops were conducted with the YAP to gather their impressions of the study results and inform conclusions. Results: At the first time point, higher social support was associated with higher distress scores (β = 0.202, p < 0.001) and AYAs with higher depressive symptoms were more likely to see a mental health professional (p < 0.01). Over time, anxiety symptoms remained stable (p = 0.090); however, depressive symptoms improved (p < 0.001). The YAP highlighted the mixed effects of social support and the under-recognition and undertreatment of distress. Conclusions: This information identifies key targets, such as social support, that can inform the design of personalized screening and intervention tools. It also highlights specific timepoints at which these efforts can be directed to mitigate distress and improve quality of life. Future research should include longer-term follow-up, qualitative explorations of distress along the disease trajectory, and ongoing co-production efforts
Prediction of Chemotherapy Response in Locally Advanced Breast Cancer Patients at Pre-Treatment Using CT Textural Features and Machine Learning: Comparison of Feature Selection Methods
Get PDFRationale: Neoadjuvant chemotherapy (NAC) is a key element of treatment for locally advanced breast cancer (LABC). Predicting the response of NAC for patients with LABC before initiating treatment would be valuable to customize therapies and ensure the delivery of effective care. Objective: Our objective was to develop predictive measures of tumor response to NAC prior to starting for LABC using machine learning and textural computed tomography (CT) features in different level of frequencies. Materials and Methods: A total of 851 textural biomarkers were determined from CT images and their wavelet coefficients for 117 patients with LABC to evaluate the response to NAC. A machine learning pipeline was designed to classify response to NAC treatment for patients with LABC. For training predictive models, three models including all features (wavelet and original image features), only wavelet and only original-image features were considered. We determined features from CT images in different level of frequencies using wavelet transform. Additionally, we conducted a comparison of feature selection methods including mRMR, Relief, Rref QR decomposition, nonnegative matrix factorization and perturbation theory feature selection techniques. Results: Of the 117 patients with LABC evaluated, 82 (70%) had clinical–pathological response to chemotherapy and 35 (30%) had no response to chemotherapy. The best performance for hold-out data splitting was obtained using the KNN classifier using the Top-5 features, which were obtained by mRMR, for all features (accuracy = 77%, specificity = 80%, sensitivity = 56%, and balanced-accuracy = 68%). Likewise, the best performance for leave-one-out data splitting could be obtained by the KNN classifier using the Top-5 features, which was obtained by mRMR, for all features (accuracy = 75%, specificity = 76%, sensitivity = 62%, and balanced-accuracy = 72%). Conclusions: The combination of original textural features and wavelet features results in a greater predictive accuracy of NAC response for LABC patients. This predictive model can be utilized to predict treatment outcomes prior to starting, and clinicians can use it as a recommender system to modify treatment
Evaluating the Proportion of Foods and Beverages in the Canadian Grocery and Chain Restaurant Food Supply That Would Be Restricted from Marketing to Children on Television and Digital Media
Get PDFBackground/Objectives: Despite evidence on the association between marketing unhealthy foods to children (M2K) and negative health outcomes, M2K remains widespread in Canada. To support mandatory restrictions, Health Canada has prioritized a monitoring strategy to assess the current state of M2K, identify gaps, and establish a baseline for future policy evaluation. This study aimed to support this initiative by updating the University of Toronto (UofT) Food Classification List and evaluating the proportion of foods and beverages in the Canadian grocery and restaurant food supply that would be permitted or restricted from M2K under Health Canada’s proposed nutrient profile model. Methods: Grocery items from the UofT Food Label Information Price 2020 (n = 24,949) and restaurant menu items from Menu-Food Label Information Price 2020 (n = 14,286) databases were evaluated using Health Canada’s M2K nutrient profile model, which assesses foods solely based on thresholds for added sodium, sugars, and saturated fat. The proportion of items permitted for or restricted from M2K was determined overall and by food and menu categories for grocery and restaurant items, respectively. Results: The updated UofT List contained n = 24,494 grocery items and n = 14,286 menu items. Overall, 83% (n = 32,664/39,235) of foods and beverages in the 2020 Canadian food supply would be restricted from M2K. Among grocery items, 23% (n = 5630) would be permitted and 77% (n = 19,202) would be restricted from M2K. Among restaurant items, only 6% (n = 837) would be permitted and 94% (n = 13,442) restricted. Conclusions: The updated UofT List supports Health Canada’s monitoring strategy and highlights the large proportion of unhealthy products in the Canadian food supply that are currently still permitted for M2K. While Health Canada’s M2K nutrient profile model is stringent, gaps remain that could allow continued M2K exposure under the current proposed policy. Ongoing monitoring and policy refinement are essential to effectively protect children from M2K and its harmful effects
Racialization and the Mandatory Power of the State: How Racialized Minority People Encounter State Child Welfare Systems
Get PDFThis dissertation examines the phenomenon of racial disproportionality within child welfare systems. It asks what explains the variation in interaction rates between racialized minority people and state child welfare systems. As the province with one of the highest proportions of racialized minority people, a decentralized child welfare model and the site of the first-ever child welfare institution established in English Canada, Ontario is not only a representative case, but also a key case to study how racialized minority people encounter child welfare services. Utilizing a historical analysis of archival data, document analysis, and interview evidence, I map how child protection affects intersectional marginalized communities, leading to varied outcomes. Drawing on King and Smith’s (2005) theory of racial orders, I characterize the competing orders as an Inequality order of structural racism and an Equality order. This dissertation reveals the extent to which the child protection system, a key arm of the state that asserts mandatory state powers and intervenes in families, is more characteristic of an Inequality order or an Equality order. I find that the experiences of racialized minority people in Ontario reflect historically institutionalized norms and structures that perpetuate systematic racism, reflective of an Inequality order. The decentralized nature of the child protection system in Ontario opens points of contestation, however, in recent years leading to the nascent emergence of an Equality order at the Peel CAS agency. Consequently, racialized minority people’s experiences with child welfare varies depending on the Children’s Aid Society (CAS) agency they encounter and the affiliations of those CAS agencies with other institutions from the government or civil society.
I contend that the delegation of authority by the provincial government to CAS allows discretionary power to the administrative authorities of individual CAS agencies and their frontline child protection workers, allowing for increased or decreased discrimination by child protection staff. Discretion does not necessarily lead to discrimination but rather is the mechanism through which discrimination may occur. Therefore, discretionary power allows for the persistence of an Inequality order or contestation and the supplanting of the previous order to enable the emergence of an Equality order.Ph.D
Characterizing Novel Resistance Responses to Pseudomonas syringae pathovar tomato DC3000 in Non-Reference Arabidopsis thaliana Accessions
Get PDFArabidopsis thaliana thrives in diverse ecological niches globally, showcasing significant intraspecific genomic variation among its accessions. This perhaps is best illustrated by the extensive variation in Nucleotide-binding leucine-rich repeat receptors complements among ecotypes. Typically, studies of the Arabidopsis thaliana - Pseudomonas syringae pathosystem focus exclusively on the reference Columbia ecotype. Thus, our study aimed to specifically investigate ETI responses exclusive to non-Col-0 A. thaliana accessions by examining resistance responses to P. syringae T3SEs HopBN1d, HopBD1g, and HopAB1q. We identified Baa-1 and Sf-2 as ecotypes resistant to these effectors. These ecotypes were reciprocally crossed with susceptible Col-0 to produce F2 lines which could be used to determine the segregation ratio of resistance. Our F2 screens revealed that resistance to PtoDC3000 carrying HopBD1g in Col-0 x Baa-1 F2 lines segregates as a dominant trait.M.Sc
Hygiene Practices Against Dermatophytic Fungi: A Review of Strategies to Combat Antifungal Resistance
Get PDFSuperficial fungal infections of the feet, such as tinea pedis and onychomycosis, are highly prevalent and frequently recurrent, often due to persistent contamination of footwear, textiles, and foot care instruments. Despite growing concern over antifungal resistance, environmental sources of reinfection remain under-recognized in clinical practice. This review critically examines historical and contemporary methods used to sanitize shoes, socks, podiatric tools, and related materials. Evidence from peer-reviewed studies published between 1938 and 2025 was analyzed across multiple disinfection categories, including chemical agents, thermal methods, laundering, ultraviolet- and ozone-based technologies, antimicrobial textiles, and sterilization protocols. Findings reveal a range of efficacies, limitations, and practical considerations across methods, with steam sterilization emerging as the most reliable for reusable instruments. A multifaceted approach combining pharmacologic treatment with consistent environmental hygiene is essential for breaking reinfection cycles and reducing antifungal resistance. This review highlights the need for clinical education and research into scalable, effective disinfection strategies
Centrifuge modeling of seepage and pollutant migration of suspended cutoff walls in saturated soils
Get PDFThis study presents an investigation of seepage and pollutant migration in a site with suspended cutoff walls through centrifuge model tests with the advantages of reduced scale in time and size at 80 g, employing an independently designed control system. The experimental setup simulated and reproduced the long-term effects of site seepage and continuous non-point source pollution release under a hyper-gravity environment for the first time. It enables in-situ and real-time monitoring of variations in pollutant concentration at the base of the downstream cutoff wall. The distribution of seepage and pollutant migration patterns in two types of suspended cutoff wall sites, namely shallow wall (12 m) and deep wall (24 m), were investigated by means of numerical simulations, with the goal of complementing and comparing to the testing data. Results indicate that the suspended cutoff wall prolongs the contaminated seepage path and delays the downstream wall’s failure, extending its service life by causing diversion effects of the site and ongoing variations in seepage direction. Although the containment impact on pollutants is greatly improved by deeper walls, the efficiency does not rise in a linear fashion with depth. Numerical simulations were also used to assess and validate the dispersion pattern of the contaminated plume and consequences of site diversion. This study provides a valuable reference for the design of suspended vertical cutoff walls at contaminated sites.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
8maw8gan: Zooarchaeology of Changing W8banaki Fishing Practices at Fort Odanak on Alsig8ntegw
Get PDFThis dissertation examines change and continuity in w8banaki fishing practices, following Euro-Canadian colonization of their territory in Québec from the 18th to the 20th century. To document these practices, I study fish and other animal remains found in archaeological contexts at the Fort Odanak site, a Jesuit mission and military fort on Alsig8ntegw (St-Francis River) in Québec. This project was performed in collaboration with the W8banaki Research Coordination Committee to better understand early practices and foodways.Pit features found in archaeological contexts at Fort Odanak contain numerous animal bones. Faunal identifications and quantification allow for the documentation of changing exploitation practices through time. Particular attention is paid to archaeological fish length reconstruction. As fishing tools influence the size of fish caught in a fishing event, the use of regression equations to predict fish total lengths from archaeological bone measurements allows for the reconstruction of fish size profiles which can be linked to specific fishing strategies.
My results show that 18th century faunal exploitation practices at Fort Odanak were geared toward the fur trade and fishing. Many fish taxa were obtained, but the brown bullhead, channel catfish and Catostomidae species were the focus of most fishing activities. Size reconstruction shows the use of line and basket fishing to capture small fish, while net fishing was used to capture larger fish. Few domestic animals introduced by the Jesuits were raised at the mission during this time. The variety of exploited species decreased in later centuries and an increased reliance on domestic animals over wild ones is noted. The diminution of the fur trade, the clearance of land for agriculture and the increased colonization of traditional land can explain this loss in access to resources and land to carry out traditional activities. Still, the perpetuation of traditional subsistence practices throughout a period of change attests to w8banaki cultural resilience. The adoption of domestic animals and agricultural practices in the 19th century is seen as a strategic adaptation to ensure physical and cultural survival in the face of colonial pressures.Ph.D