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Advancing the Use of the Damage Rating Index (DRI) for Evaluation of Concrete Affected by Internal Swelling Reactions (ISR)
No full textThe damage rating index (DRI) is a microscopy tool and methodology used to identify deterioration caused by internal swelling reactions (ISR) in concrete. The DRI was initially developed to evaluate concrete affected by alkali-aggregate reaction (AAR) and has since begun to be employed for other types of ISR. It utilizes a point-count method to count distinct petrographic and distress features across a surface, providing insight into the type, extent, and pattern of deterioration. This study addresses research gaps related to the DRI’s ability to distinguish between ISR mechanisms, the connection between microscopy and mechanical responses, operator variability, and the use of technology for more efficient data collection. This thesis is paper-based and includes five papers aimed at addressing the identified research gaps. The first topic is divided into two papers, with the first exploring the tool's adaptability by modifying the counting method to better describe deterioration due to delayed ettringite formation (DEF). The study illustrates the enhanced capability of the DRI to characterize DEF-induced deterioration more effectively. The second paper assesses the counting method in relation to mechanical responses. The second topic and third paper investigates the relationship between distress features and mechanical responses. The research employs linear regression through detailed analysis, establishing significant correlations that provide valuable insights into the engineering implications of distress features observed under microscopy. The third topic is variability, and the fourth paper presents an approach for autonomous operator training aimed at improving skill acquisition and reducing variability. This approach proposes a robust training framework, demonstrating promising results in standardizing operator performance. The final topic and fifth paper evaluate a technique for assessing the outcomes of automating the collection of distress feature counts via images. The study compares the accuracy and efficiency of operator-based versus machine-based data collection, highlighting the advantages of automation in terms of consistency and speed. The combined findings from these studies offer a comprehensive understanding of the DRI’s adaptability to ISR mechanisms, distress feature analysis, autonomous training methodologies, and automated evaluation techniques. Future research can build upon these findings and approaches to further innovate and refine the use of the DRI in engineering practices
Étude d’une approche d’intervention dans le cas de difficultés d’écoute chez les enfants d’âge scolaire
No full textLes enfants ayant un développement neurotypique doivent déployer un effort considérable pour écouter en présence de bruit. Cet effort est encore plus marqué chez les enfants ayant des difficultés d’apprentissage. En effet, plusieurs de ces enfants présentent également des difficultés d’écoute particulièrement dans le bruit ou un trouble du traitement auditif. Cette thèse propose une approche d’intervention novatrice et des outils pour explorer de l’effet de cette intervention sur les capacités d’écoute et la participation à l’aide d’un devis expérimental à cas unique à niveaux de base multiple non simultané.
Dans la première phase, une revue de la portée a été effectuée pour identifier et synthétiser les études récentes sur les interventions destinées aux enfants d'âge scolaire présentant des difficultés de traitement auditif ou un trouble de traitement auditif. Des interventions visant les habiletés cognitives et langagières, ainsi que l'utilisation de prothèses auditives et d’aide de suppléance à l’audition ont été répertoriées. La majorité des approches d’intervention étaient des entrainements auditifs. La revue a souligné le manque d’outils disponibles pour mesurer la perception des enfants quant aux changements apportés par les interventions et a mis en évidence la nécessité de mener des recherches supplémentaires sur les interventions Top-Down.
Dans la deuxième phase, deux outils de mesure du rendement ont été conçus pour explorer les changements de manière répétée dans le cadre du devis à cas unique. Le Test de phrases filtrées (TPF) a été développé pour explorer la capacité à utiliser le contexte des phrases pour identifier un mot-clé dans des conditions d’écoute défavorables. Le TPF comprend des phrases dégradées par un filtre passe-bas centré à 750 Hz. Le Questionnaire des Situations d’Écoute Difficiles (QSED) a été élaboré pour identifier les situations d’écoute les plus difficiles et les plus importantes pour les enfants et a été soumis à une évaluation de la validité de contenu par un comité d’experts, ainsi que d’une évaluation de la validité apparente auprès d'enfants.
Dans la troisième et dernière phase, des enfants ayant des difficultés d’écoute en présence de bruit ou de parole compétitive ont suivi un programme d’apprentissage de stratégies de réparation des bris de communication, nommé RéBriCo (Réparation des Bris de Communication), développé par l’auteure de cette thèse. L’effet de ce programme sur les capacités d’écoute et la participation de ces enfants a été exploré. Cinq participants âgés de 8 à 11 ans ont suivi des séances hebdomadaires de 60 minutes. Divers outils de mesure du rendement ont été utilisés, soit un test de perception de la parole dégradée, un test de perception de la parole dans le bruit, une épreuve évaluant la compréhension de paragraphes présentés à l’orale, et des épreuves évaluant la mémoire auditive et la mémoire de travail. Des mesures de potentiels évoqués auditifs de latence longue (P1-N1-P2-N2) ont été effectuées. L’effet du programme sur la participation dans les activités de la vie quotidienne a été évalué grâce à des questionnaires remplis par les enfants et les parents ainsi que des vidéos où les enfants apprenaient à jouer à des jeux de cartes tout en vivant de multiples bris de communication. Les résultats ont montré que ce programme peut améliorer certaines capacités d’écoute et la participation des enfants dans leur vie quotidienne. Les outils conçus, le QSED et le TPF, ont montré leur utilité pour mesurer les changements au cours des interventions. Les résultats ouvrent la voie à des recherches futures pour optimiser les interventions en audiologie et améliorer la qualité de vie des enfants ayant des difficultés d’écoute notamment dans le bruit
Cytisine compared to combination nicotine replacement therapy to reduce cigarette consumption in relapsed smokers: protocol for a pilot randomized controlled trial
No full textAbstract Background Cigarette smoking is a leading cause of death and disease, including those related to the cardiovascular system. Cytisine is a plant-based medication, which works in a similar mechanism to varenicline. It is safe, efficacious, and cost-effective for smoking cessation. While there are effective therapies such as nicotine replacement therapy, bupropion, varenicline, and cytisine for smoking cessation, relapse remains common. It is unclear how best to support these individuals. This study aims to assess the feasibility of randomizing patients who relapse to combination NRT or cytisine after admission to a cardiac hospital. Study design Randomized, two-group parallel feasibility trial. Methods This trial will recruit relapsed smokers from the University of Ottawa Heart Institute. Participants will be randomized 1:1 to receive cytisine or combination NRT, alongside counseling and follow-up support. Feasibility outcomes include recruitment rates and treatment completion. Secondary outcomes include smoking cessation rates and adverse events. A total of 60 participants will be recruited using stratified randomization by sex to ensure gender balance. Data will be analyzed descriptively, focusing on feasibility and efficacy measures to inform future trials. Discussion The primary aim of this study is to evaluate the feasibility of recruiting patients who were recently admitted to the hospital and have relapsed to smoking within 180 days post-discharge. This will inform future studies aimed at recruiting patients who have relapsed to understand how best to support them to quit smoking. This study will also compare the acceptability, efficacy, and safety of cytisine compared to combination NRT, as demonstrated in previous studies in other populations. Notably, cytisine’s shorter regimen and natural composition broaden its appeal, potentially supporting a wider spectrum of people who smoke. The study’s robust design, infrastructure, and expertise enhance its feasibility. Future research avenues, especially among cardiac patients and relapsed individuals, promise further insights, potentially transforming cessation strategies worldwide. Trial registration Registered at Clinicaltrials.gov (CT04286295) on 14 March 2022. https://clinicaltrials.gov/study/NCT04286295?locStr=Canada&country=Canada&intr=Cytisine&rank=3
Agency and Persons: How We Become Who and What We Are
No full textThis doctoral dissertation articulates a libertarian theory of free will and moral responsibility alongside a narrative view of personal identity. In this dissertation, I build upon and expand Robert Kane’s libertarian theory to create a mitigation strategy for dealing with a perennial problem for libertarian theories of freedom and moral responsibility: the problem of luck. I argue that Kane’s basic idea of self-forming actions or SFAs can be built upon to show how the luck objection can be undercut. I argue that SFAs take place within a larger narrative structure and that when we make SFAs we are also engaged in what Kane calls value experiments. I construct
a theory of narrative personal identity and put it to work to show how the problem of luck is mitigated and that SFAs are not just a matter of luck
A Study of Pierre Bourdieu's Theory of Inequality Through The Inheritors, Reproduction in Education, Society, and Culture, and The Logic of Practice
No full textThis thesis examines Pierre Bourdieu's enduring contributions to sociology, focusing on three seminal works - The Inheritors: French Students and Their Relation to Culture (1979 [1964]), Reproduction in Education, Society, and Culture (1970), and The Logic of Practice (1990) - which reveal the mechanisms by which inequality is reproduced within ostensibly neutral social institutions. Through a systematic textual analysis, it traces the evolution of Bourdieu's theoretical framework, moving from empirical critiques of education to a comprehensive theory of social practice.
Central to this research is Bourdieu's theory of practice, which reconciles the interplay between structure and agency, illustrating how social structures shape individual actions while individuals, enabled and constrained by habitus and capital, navigate these structures. The study critically engages with Bourdieu's key concepts - habitus, field, and capital - and their roles in perpetuating inequality through symbolic violence and cultural reproduction. It bridges Bourdieu's insights with those of Marx and Gramsci, emphasizing shared themes of power dynamics and cultural hegemony.
The synthesis chapter integrates Bourdieu's ideas across his seminal texts while addressing critiques of structural determinism from scholars such as Raymond Boudon, Patricia Broadfoot, and Paul Vogt. It highlights the adaptability of Bourdieu's framework to contemporary challenges, including educational inequities and broader societal dynamics, underscoring his focus on reflexivity and agency.
By connecting theoretical abstraction with practical strategies, this thesis advances sociological discourse, offering actionable insights into mechanisms of inequality and reaffirming Bourdieu's legacy as a foundational figure in contemporary sociology
Investigating Biological Sex Differences in a Preclinical Model of Acute Lung Injury
No full textDespite decades of research, Acute Respiratory Distress Syndrome (ARDS) remains a leading cause of mortality in critically patients, with treatments limited to supportive care. Biological sex is increasingly recognized as a key variable influencing disease progression and therapeutic outcomes, but its role in ARDS is underexplored. Clinical findings have been inconsistent, highlighting the need for robust preclinical research. This thesis addresses these gaps through two studies: 1) a systematic review revealing that few studies of LPS-induced acute lung injury (ALI) models report sex stratified data, but the available data suggests males tend to fare worse; and 2) experimental studies refining the LPS administration routes in this model. These refinements reduced unwanted variability and enhanced the detection of meaningful biological differences, finding that male mice exhibited more severe lung injury. Together, these findings lay the groundwork future research (e.g., a multilaboratory studies) that can further address these gaps
Uncovering the Roles of EAF1 in the Regulation of Lipid Synthesis and Membrane Composition in Saccharomyces Cerevisiae
No full textThe yeast lysine acetyltransferase NuA4 has been implicated in regulating various aspects of metabolism, including a poorly defined role in lipid homeostasis. While classically known to acetylate histones, regulating gene expression, NuA4 also targets several non-histone proteins for acetylation. Here, I use a combination of functional genomics and fluorescent microscopy to define a novel role for NuA4 in regulating phospholipid availability for organelle morphology. First, I characterized that disruption of the NuA4 complex resulted in 70% of cells displaying deformed nuclei and nearly 50% of cells exhibiting high levels of vacuolar fragmentation. Interestingly, the deformed nuclei appeared to occur at all stages of the cell cycle, indicating an underlying dysregulation of lipids driving phospholipid metabolism. With deletion or mutation of additional genes involved in phospholipid synthesis, I was able to partially rescue nuclear deformation but not vacuolar fragmentation. To investigate the cause of these phenotypes further, I probed whether there could be a defect in a critical autophagy process known as piecemeal microautophagy of the nucleus (PMN). PMN acts to selectively degrade excess nuclear membrane into the vacuole and is performed at the nuclear-vacuole junction (NVJ). Interestingly, cells deficient in NuA4 also showed severe defects in the formation of NVJ and the function of PMN. To determine the cause of these defects, I sought to determine if these phenotypes were due to an uncharacterized relationship between NuA4 and Pah1, an enzyme that converts phosphatidic acid into diacylglycerol, which favours the accumulation of lipid droplets over phospholipids that are used for membrane expansion. NuA4 subunit Eaf1 was required for Pah1 localization to the inner nuclear membrane, and artificial tethering of Pah1 to the nuclear membrane rescued nuclear flare and vacuole fragmentation defects but not defects related to the formation of NVJs. Mutation of a candidate NuA4 acetylation site on Pah1 also resulted in aberrant Pah1 localization and defects in membrane morphology and NVJ. This work defines a critical role for NuA4 modification of Pah1 in the regulation of lipid pools that define the characteristics and function of organelle membranes. Given the high level of conservation of NuA4 with the human Tip60 complex, as well as Pah1 with human lipin, this work is highly relevant to human disease
Building engaging online weight loss communities using a communities of practice framework
No full textThe rise of internet use and social media platforms has revolutionized how people can access health and weight loss information and how providers can promote programs to geographically dispersed populations through virtual networks. Sustained engagement in virtual programs contributes to whether members will successfully reach their health and weight loss goals, yet identifying how to support sustained engagement remains an elusive quest. This qualitative study examined members’ perspectives of the factors that contribute to their ongoing engagement in a social media (Facebook)-based weight loss program. We argue that sustained engagement of members is fostered through attention to supporting members’ progressively increasing participation in a community of practice (Lave and Wegner, 1991). Findings demonstrated that a supportive, non-judgemental online community that provides ready access to knowledge in multiple formats and supports interactions and situated learning with experts and more experienced members, first encourages legitimate peripheral participation, which grows to sustained engagement.Funding: This research was supported by the Social Science and Humanities Research Council [grant #1346350
Blood biomarker fingerprints in a cohort of patients with CHRNE-related congenital myasthenic syndrome
No full textAbstract Mutations in CHRNE encoding the epsilon subunit of acetylcholine receptor result in impaired neuromuscular transmission and congenital myasthenic syndrome (CMS) with variying severity of symptoms. Although the pathophysiology is well-known, blood biomarker signatures enabling a patient-stratification are lacking. This retrospective two-center-study includes 19 recessive CHRNE-patients (AChR deficiency; mean age 14.8 years) from 13 families which were clinically characterized according to disease severity. 15 patients were classified as mildly and 4 patients as moderate to severely affected. Seven known pathogenic and one unreported variant (c.1032 + 2_1032 + 3delinsGT) were identified. Biomarker discovery was carried out on blood samples: proteomics was performed on white blood cells (WBC; n = 12) and on extracellular vesicles (EV) purified from serum samples (n = 7) in addition to amino acid profiling (n = 9) and miRNA screening (n = 18). For miRNA studies, 7 patients with other CMS-subtypes were moreover included. WBC-proteomics unveiled a significant increase of 7 and a decrease of 36 proteins. In silico studies of these proteins indicated affection of secretory granules and the extracellular space. Comparison across patients unveiled increase of two vesicular transport proteins (SCAMP2 and SNX2) in severely affected patients and indeed EV-proteomics revealed increase of 7 and decrease of 13 proteins. Three of these proteins (TARSH, ATRN & PLEC) are known to be important for synaptogenesis and synaptic function. Metabolomics showed decrease of seven amino acids/ amino acid metabolites (aspartic and glutamic acids, phosphoserine, amino adipate, citrulline, ornithine, and 1-methyhistidine). miRNA-profiling showed increase miR − 483 − 3p, miR-365a-3p, miR − 365b − 3p and miR-99a, and decrease of miR-4433b-3p, miR-6873-3p, miR-182-5p and let-7b-5p in CHRNE-patients whereas a comparison with other CMS subtypes showed increase of miR − 205 − 5p, miR − 10b − 5p, miR-125a-5p, miR-499-5p, miR-3120-5p and miR − 483 − 5p and decrease of miR − 1290. Our combined data introduce a molecular fingerprint on protein, metabolic and miRNA level with some of those playing different roles along the neuromuscular axis
Optimizing Large Scale Particle Image Velocimetry Using a Multi Camera System
No full textHydrometric monitoring plays a vital role in Canada’s environment. It is used for flood monitoring, climate change modelling, water resources engineering design and much more. Environment and Climate Change Canada (ECCC) operates over 2200 hydrometric stations across the country, collecting and publishing near real-time water level and discharge data. Discharge measurements are required to validate rating curves after major rainfall events and periodically throughout the year. Conventional methods can pose safety risks to hydrometric technologists in high flows. Additionally, in flashy streams at remote locations it is challenging to travel to the station in time to obtain the peak discharge. This is where methods such as image velocimetry could be used as an alternative to conventional methods. Numerous surface velocimetry algorithms have been created and adapted for the field, one of which is large scale particle image velocimetry (LSPIV). LSPIV utilizes video recordings of a river surface to estimate the surface velocity field, based on a cross-correlation technique that identifies the displacement between subsequent image frames of surface roughness or scatterers within individual interrogation areas (IA). This study aimed to tackle challenges of both LSPIV and
stereoscopic LSPIV. A novel multi-camera LSPIV method was created by combining the best portions of the surface velocity field obtained by each camera. The channel was split in the middle and the portions of the surface velocity field for each half of the channel obtained from the respective adjacent camera were retained and then combined across the cross-section. Single camera LSPIV had absolute percent differences of 11.73%, 26.41%, and 21.05% for the gauge house camera, left bank (bridge) camera and right bank (bridge) camera, respectively, compared to ADCP measurements. The multi-camera method resulted in an improvement compared to the best single camera estimates in four of five surveys and had an absolute average difference of 8.19% compared to the ADCP. The results also reinforced the importance of surface texture and environmental conditions in LSPIV analysis