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Assessment of Chloride Resistance and Binding Mechanism of Portland-Limestone Cement (PLC) Concrete
No full textConcrete production is responsible for approximately 8% of global CO₂ emissions, primarily due to the high clinker content and energy demands associated with Portland cement (PC) manufacturing. In response to growing environmental concerns, Portland-limestone cement (PLC), which partially replaces clinker with interground limestone, and the use of supplementary cementitious materials (SCMs) such as fly ash and slag have been widely promoted as low-carbon alternatives. However, the durability performance of high-limestone PLC systems remains a topic of concern, particularly in terms of chloride ingress resistance and associated binding behavior. This study investigates the chloride resistance and chloride binding capacity of fifteen PLC concrete mixtures, incorporating varying limestone replacement levels and SCM types, under a water-to-powder ratio (W/P) of 0.4. A combination of bulk diffusion testing and acceleration tests was employed. Chloride binding was assessed using both acid-soluble and water-soluble extractions to quantify total and free chloride contents. The results show that SCMs significantly enhance chloride resistance. A strong correlation was observed between electrical resistivity and the apparent diffusion coefficient (Da), emphasizing the role of pore structure in chloride resistance under PLC systems. Moreover, the Langmuir isotherms provided the best fit for chloride binding behavior across all pure PLC mixtures, and analysis revealed that the Al₂O₃/SO₃ ratio, rather than the Al₂O₃ content, is a more reliable indicator of chloride binding capacity. While fly ash contributed to enhanced chloride binding, the effect of slag was less dependent on the limestone content due to its different chemical binding mechanisms. These findings underscore the need for a high quality control of cement manufacturing along with optimized concrete mix proportioning to ensure the reliable performance of high-limestone, low-carbon PLC mixtures in chloride-exposed environments
Borderline Personality Features in Adolescence Predict Dating Violence Perpetration in Early Adulthood
No full textBorderline personality pathology and intimate partner violence (including teen dating violence) are significant public health concerns that have been found to negatively affect well-being across the lifespan. Researchers have consistently shown that borderline personality pathology, both clinical and subclinical, can increase the likelihood of intimate partner violence perpetration and victimization in adulthood. There is less research on these associations in adolescence. Additionally, the developmental pathway of borderline personality pathology during adolescence is still not well defined, despite adolescence being a critical developmental window for personality pathology and for completing developmental tasks related to social connection and identity formation. Rooted in attachment, developmental biosocial, and differential susceptibility theories, I examined developmental trajectories of borderline personality features in adolescence (from ages 14 to18) in the prediction of dating violence experiences (victimization and perpetration) in early adulthood (ages 19 and 20) in a community sample. Using a longitudinal, person-centred design, three trajectories of borderline personality features were identified: low-, moderate-, and high-stable, with girls overrepresented in the high-stable group and boys overrepresented in the low-stable group. Contrary to expectations grounded in the extant literature, borderline personality feature trajectory group membership and dating violence victimization were not associated. However, high-stable borderline personality feature trajectory group membership and dating violence perpetration were linked. Gender and experiences of child maltreatment were also associated with dating violence victimization and perpetration, and a strong co-relation between perpetration and victimization was found. These results add to the literature on both borderline personality pathology and dating violence in adolescence and highlight the importance of early intervention. Possible avenues of intervention are explored, focusing on emotion regulation, mentalization, and family relationships
The Imagination of Sexuality in Society and Culture: An Inquiry into the Erotic Literature of Ming and Qing Society and Gender (1600-1800)
No full textYanqing (erotic and love) literature has a long history in China and peaked during the mid-to late-Ming period (the mid 15th to 1644), paralleling the rise of luxury consumption and commerce. Many writers engaged in this genre, including a significant number of women. In an era dominated by traditional Confucian norms, it is notable how these female authors transcended social expectations to participate in literary pursuits, especially in yanqing literature, which was often considered outside the mainstream. More remarkably, women began forming literary communities centered on regional connections and establishing literary exchanges with male writers. This increased visibility allowed female writers to document their voices, marking a significant presence in Chinese literary history
Investigating the Metabolic Mechanisms Underlying Natural Killer Cell Dysfunction
No full textIn cancer, Natural Killer (NK) cells often lose their immune functions and fail to eliminate tumour cells in a phenomenon called NK cell dysfunction. Unfortunately, the mechanisms and drivers of NK cell dysfunction are unknown, making it hard to revert it therapeutically. As NK cell function is tightly regulated by their metabolic state, we hypothesize that dysregulated metabolism drives NK cell dysfunction. Thus, we investigated the metabolism of dysfunctional NK cells compared to functional NK cells using an in vitro model of chronic stimulation. Dysfunctional NK cells had decreased glycolysis and transcription of glucose transporters. An untargeted metabolomics screen revealed that the pentose phosphate pathway, nucleotide metabolism, arginine metabolism and glutathione synthesis were disrupted in dysfunctional NK cells. Preliminary data shows that glutathione supplementation increased function and glycolysis in dysfunctional NK cells. This project aims to identify metabolic drivers of NK cell dysfunction to reveal new targets for cancer immunotherapies
Youth Cannabis Use in Ontario During the COVID-19 Pandemic: A Longitudinal Cohort Study
No full textObjectives: This study aimed to examine changes in cannabis use, motivations for changing cannabis use patterns, and symptoms of cannabis use disorder (CUD) among Ontario youth (16-30) who used cannabis during the COVID-19 pandemic.
Methods: We analyzed the association between changes in cannabis use and motivations for increased use with changes in symptoms of CUD measured with the Cannabis Use Disorder Identification Test – Revised (CUDIT-R) using linear regression modelling.
Results: 58% of respondents reported increasing their cannabis use due to the COVID-19 pandemic, which was associated with increases in CUDIT-R scores at follow-up compared to baseline. This association of increased CUDIT-R scores was more pronounced among younger participants. Boredom and loneliness were identified as significant contributors to increases in cannabis use and symptoms of CUD.
Conclusion: Our findings underscore the need for targeted harm reduction programs to delay onset and discourage problematic cannabis use
Determinants of Successful Cross-Border Mergers and Acquisitions
No full textThis study investigates the impact of payment methods on the performance of cross-border mergers and acquisitions (M&As) initiated by U.S.-based acquiring firms. While existing literature provides mixed evidence on whether stock- or cash-financed deals yield superior outcomes, this study systematically evaluates the effect of financing choice on short-term market reactions, long-term operating performance, and long-term abnormal stock returns. Using a sample of 4,937 completed M&A transactions from 2000 to 2020, the analysis employs cumulative abnormal returns (CARs) to capture immediate investor responses, an intercept model of benchmark-adjusted cash flow returns to measure operational outcomes, and value-weighted buy-and-hold abnormal returns (BHARs) to assess post-acquisition stock performance.
The findings do not support the hypothesis that stock-financed cross-border acquisitions outperform cash-financed ones. Instead, cash-financed deals - especially those involving foreign targets - are associated with stronger short-term CARs and more favorable long-term operating performance. Moreover, stock-financed cross-border transactions exhibit significant underperformance in post-deal stock returns, with a BHAR of -51.5 percent over three years. These results suggest that investor skepticism toward stock-financed international deals may be warranted, and that liquidity strength and transaction certainty remain central to deal success.
By focusing exclusively on U.S. acquirers and combining market-based and accounting-based methodologies, the study contributes to a more nuanced understanding of how financing strategies affect acquisition outcomes in cross-border contexts. The results offer practical implications for corporate decision-makers and institutional investors evaluating the long-term viability of international expansion strategies
Exploring the Role of PGC-1α in Adult Neurogenesis and its Impact on Behavior
No full textAdult hippocampal neurogenesis, the process of generating new neurons throughout life, remains a dynamic and tightly regulated process, vital for cognitive performance and emotional regulation. Being an energetically demanding process, its regulation by mitochondria remains incompletely understood. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) is a master regulator of mitochondrial function, yet its role in adult neurogenesis has not been clearly defined. Here, we investigate the necessity of PGC-1α in neural stem and progenitor cells (NSPCs) in a tamoxifen-inducible conditional knockout (cKO) mouse model. Using immunohistochemistry and behavioral assays, we assessed the consequences of PGC-1α loss on neurogenesis, anxiety and cognition at 3- and 6-months post-tamoxifen administration. Quantification of neurogenesis markers revealed a significant impairment by 3 months post-induction. Behaviorally, PGC-1α cKO mice displayed a temporary improvement in anxiety and working memory, neither of which were sustained, while spatial learning and memory results were inconclusive. Interestingly however, a significant long-term recognition memory deficit emerged in male cKO mice at 6 months post-induction. Our findings suggest that PGC-1α is essential for maintaining adult hippocampal neurogenesis and long-term recognition memory
Analyser le changement agraire dans une commune du Sénégal : clientélisme, grand modernisme et mobilisations restreintes
No full textCette recherche analyse des dynamiques de pouvoir dans le contexte du changement agraire dans une commune rurale du Sénégal. En optant pour un assemblage théorique, je répondrai aux questions suivantes: Comment l'État et ses relais locaux cherchent-t-ils à prévenir toute remise en cause de pratiques patrimoniales de l'accaparement foncier dans cette commune? Comment expliquer la relative faiblesse de la mobilisation paysanne face aux problèmes d'accaparement dans cette commune? Et pour finir, Comment expliquer l'échec des programmes de modernisation foncière dans cette même commune?
La recherche étudie les différentes stratégies employées par l'État et ses relais locaux pour conserver et pérenniser un clientélisme décentralisé autour des ressources foncières de cette commune. Ce clientélisme décentralisé institué dans cette commune est hérité des gouvernances des différents chefs d'État qui se sont succédé au Sénégal depuis sa création en 1960. L'élection d'un représentant local au sein du conseil rural de la commune, opposé à ces pratiques, déclenchera un ensemble d'actions de la part du gouvernement et de ses représentants locaux pour la conservation des intérêts fonciers des différents patrons et clients. Ces ingénieries du pouvoir permettront d'écarter définitivement cet élu, de toutes futures fonctions électives dans la commune.
Cette thèse analyse également les raisons permettant d'expliquer une quasi-absence de mobilisation collective contre une entreprise agro-industrielle accaparant des terres des populations locales illégalement. Ceci est caractérisé par une absence de mobilisation des ainés et à ce qui s'apparente à une infrapolitique des jeunes hommes du village. La mobilisation d'un ensemble théorique comprenant, la théorie du pouvoir de Dahl et l'infrapolitique de Scott me permet d'affirmer que l'absence de mobilisation des ainés est due aux relations de pouvoirs au sein desquelles ils sont enchevêtrés et celles-ci limitent leur champ d'action. Les jeunes hommes quant à eux opposent une mobilisation discrète à l'entreprise, principale pourvoyeuse d'emplois, pour dénoncer les postes d'ouvriers agricoles qui leur sont proposés ainsi que leurs conditions de travail.
Cette thèse analyse également les manifestations de l'échec d'un programme de développement agricole, le Programme pour le Développement Inclusif de l'Agrobusiness au Sénégal (PDIDAS), lancé en 2015 par le gouvernement sénégalais. Il prévoyait des mesures pour l'attraction d'investisseurs dans neuf communes du nord du Sénégal. Ce programme de grand-modernisme foncier s'est cependant soldé par un échec qui s'explique par sa logique court-termiste et la non-prise en compte du contexte local par ses concepteurs. Ainsi, les résultats visibles du Programme dans la commune de Mbane montrent qu'aucun des objectifs affichés n'a été atteint.
À partir de l'analyse de phénomènes liés au changement agraire au Sénégal, cette thèse vise à montrer que les dynamiques d'exclusions des populations locales dans ce contexte comprennent une variété de processus de domination instaurées par les acteurs qui bénéficient de ce changement agraire. Ainsi cette recherche apporte une contribution particulière sur certaines conséquences liée à la néolibéralisation du monde agraire dans un pays du Sud.
Cette thèse suit le modèle d'une "thèse par articles", dont les procédures ont été définies par l'École d'études politiques. La thèse est donc structurée autour de trois chapitres 'empiriques' qui ont été soumis à des revues académiques. Il s'agit des chapitres 3, 4, et 5
Developing a role for patients and the public in the implementation of health and social care research evidence into practice: the PIPER study (Pathways to Implementation for Public Engagement in Research) realist evaluation protocol
No full textAbstract Background While patients and the public are routinely involved as active collaborators in health and social care research, they are rarely involved in the implementation of research. The PIPER (Pathways to Implementation for Public Engagement in Research) research questions are: 1. How can patients, carers, service users and the public be involved in the implementation of health and social care research evidence into practice? 2. What types of roles, contributions and impact can patients, carers, service users and the public make to the implementation of health and social care evidence into practice? 3. How can we support patients, service users, carers and the public to contribute to the implementation of health and social care evidence into practice? 4. How can we co-produce the knowledge that explores a greater role for patients, carers, service users and the public in the implementation of health and social care evidence into practice? Methods Our overarching methodological framework is realist evaluation. This study includes four work packages with a cross-cutting co-production theme. •Work Package 1: A realist review of published literature, grey literature and sources such as blogs. •Work Package 2: Interviews with 40–60 people using a realist approach. •Work Package 3: A series of workshops to co-design the PIPER Toolkit. •Work Package 4: Pilot evaluation of the PIPER Toolkit. Results The scoping of the literature will be informed by the development of an initial programme theory that identifies the potential breadth of the field of public involvement in implementation. Data from the WP2 interviews will be used to iteratively refine the development of the context, mechanism and outcomes (CMOs). This will inform the PIPER Toolkit, which will consist of a set of ‘Guiding Principles’ supported by ‘Practical Resources.’ The PIPER Toolkit will enable an individual or a group to plan and undertake implementation activities. More specifically, the Guiding Principles will enable the Practical Resources to be tailored to specific implementation strategies for an individual or group. Discussion Patient and public involvement in implementation is an emerging area of practice and is likely to significantly strengthen over the next decade. The PIPER Toolkit will recognise this early stage of development, identifying the key system enablers that organisations need to have in place to support this activity. The Toolkit will support patients and the public and implementation teams to navigate the field of implementation practice. The PIPER study will challenge the field of implementation and knowledge mobilisation research to develop clearer forms of partnership with patients and the public in both research and practice.Plain English Summary Background Why are we doing this study? Patients and the public are often involved in research studies about health and social care, contributing to how research is designed, conducted and shared. However, they are rarely involved in moving the research evidence into practice. This is called implementation. The PIPER (Pathways to Implementation for Public Engagement in Research) research questions are: What we want to find out 1. How can patients, carers, service users and the public be involved in the implementation of health and social care research evidence into practice? 2. What types of roles, contributions and impact can patients, carers, service users and the public make to the implementation of health and social care evidence into practice? 3. How can we support patients, service users, carers and the public to contribute to the implementation of health and social care evidence into practice? 4. How can we co-produce the knowledge that explores a greater role for patients, carers, service users and the public in the implementation of health and social care evidence into practice? Methods What we plan to do We plan to use a research approach (realist evaluation) that focuses on finding out what works, for whom, why and in what way, in four work packages: •Work Package 1: We will review relevant research and sources of knowledge including both peer-reviewed and grey literature. •Work Package 2: We will interview 40-60 people with either experience of or interest in PPIE in implementation. •Work Package 3: We will use a series of workshops to co-design the PIPER Toolkit, a set of resources, which will help with PPIE in implementation. •Work Package 4: We will pilot the PIPER Toolkit to make sure it works. Results The initial review of literature helped early mapping to identify the potential breadth of the field of public involvement in implementation. This will inform the PIPER Toolkit. PIPER will consist of a set of ‘Guiding Principles’ supported by ‘Practical Resources’ that will help an individual or a group to get involved in implementation activity. Discussion What we aim to achieve Patient and public involvement in implementation, rather than in research is new and is likely to evolve in the future. The PIPER Toolkit will support patients and the public who wish to be involved in implementation and individuals who are involved in moving research findings into practice. It will also help organisations understand what needs to be in place to support patient and public involvement in implementation
Real-Time Player Engagement Measurement in Video Games
No full textPlayer engagement is crucial for video games, directly impacting satisfaction, retention, and commercial success. Game developers currently rely on post-hoc analytics or sales metrics that cannot capture real-time engagement fluctuations, while research approaches depend on intrusive methods requiring specialized equipment, creating a gap between practical needs and current capabilities.
This thesis investigates non-intrusive player engagement measurement methods for both game developers seeking practical optimization tools and researchers studying engagement dynamics. It identifies Flow Theory - which posits optimal engagement occurs when skill and challenge are balanced - as a promising framework for real-time prediction.
The MultiPENG study evaluated engagement across multiple modalities, revealing human judges achieved only 50% accuracy with poor inter-rater agreement (Krippendorff's α = 0.04-0.09). Computational approaches demonstrated effective performance, with facial footage (63% accuracy), EEG signals (61%), and eye metrics (59%) showing that the webcam-based approach offered the best balance between performance and practicality. Most significantly, a model using only player skill and challenge as predictors (67% accuracy) performed on par with complex multimodal approaches (65% accuracy), empirically validating Flow Theory. Despite these promising results, the observed "cold-start" sensitivity suggests careful interpretation when generalizing to new participants.
Building on these insights, a novel telemetry-based framework was developed using PlayerUnknown's Battlegrounds - a challenging case study selected for its complex environment combining shooting, combat, scavenging, survival mechanics, and large-scale multiplayer interactions across diverse gameplay phases. The framework's hybrid architecture combining Graph Convolutional Networks with Transformers outperformed Transformer-only models (73% vs. 67% accuracy). Requiring just one minute of gameplay data, the system can proactively forecast engagement by estimating skill and challenge in future timesteps, and then mapping them to an engagement level. Performance matches questionnaire-based methods while operating non-intrusively with standard game telemetry.
The primary contributions include: (1) the MultiPENG dataset with synchronized data across modalities enabling direct comparison; (2) empirical validation of Flow Theory, demonstrating skill-challenge metrics can match complex multimodal approaches; (3) a methodology for measuring skill and challenge directly from gameplay telemetry; and (4) a real-time engagement framework combining Graph Convolutional Networks with Transformers that enables adaptive experiences without specialized equipment. These contributions serve game developers seeking player experience optimization tools and researchers investigating engagement dynamics in interactive systems