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Composing entries for the cartulary of Theuley in twelfth-century France
No full textThe foundation of the Cistercian abbey of Theuley, located in Burgundy, France, is
described in its cartulary which was composed in the late twelfth or early thirteenth century.
Despite an especially rich archive, Theuley has been little studied as a result of its distance from
the chief cultural centres of Dijon, Langres and Besançon as well as the presence of a large
number of its documents being in private hands. This thesis examines the first few entries of the
cartulary by means of a careful historical analysis of the Latin text, aided by a comparison to
other sources, both in manuscript and printed forms. All the studied texts in the cartulary have
been found to use extracts from other formal documents, but with significant additions and
deletions. In a few cases, the extracts themselves appear to be used in earlier donations with
completely different donors and different witnesses. The author of the cartulary both deleted
dates from the extracts and added a date to the foundation document. The composition of this
cartulary was clearly not a simple copying of existing documents. This study thus contributes to
the developing understanding of the varied nature of cartularies in the medieval world
Validation of large Eddy simulations for an offshore wind farm: the influence of sea surface drag on wake recovery
No full textOffshore wind energy is a critical component of the global transition to renewable resources, but the
efficiency of large wind farms is often limited by aerodynamic wake effects from upstream turbines.
Recovery of these wakes, which is driven by turbulent mixing with the surrounding atmosphere, is strongly
influenced by the conditions on the ocean surface. This thesis presents a numerical investigation into
the physical mechanisms connecting surface aerodynamics to wind turbine wake dynamics, with the dual
objectives of first validating an in-house simulation framework and subsequently using it to investigate the
influence of surface drag on wake recovery. Large-eddy simulations of a 50-turbine (10 × 5) model-scale
wind farm were performed using an actuator disk model and validated against benchmark experimental
data from the EPFL wind tunnel, demonstrating excellent agreement. The validated model was then
used to compare a low-drag baseline case (d ≈ 0.0040) with a high-drag rough surface case (d ≈
0.140). The primary scientific finding is that a higher surface drag coefficient significantly amplifies the
shear production of turbulent kinetic energy, −⟨′′w′′⟩(∂⟨ū⟩/∂), at the limits of the wake, with peak
production values more than double compared to the baseline. These results lead to the conclusion that
the aerodynamic condition of the ocean surface is a crucial factor in wake recovery, introducing a crucial
design trade-off: While rougher seas accelerate wake recovery for downstream turbines, they also increase
turbulent loading and may alter the performance of the leading turbine row. This work provides insight
into this relationship, informing future strategies for wind farm design and the potential for co-locating
with wave energy systems
Design, analysis, simulation, and control of a cost-optimized hybrid power system for urban Pakistan
No full textThe escalating energy demand in Pakistan has resulted in a significant energy crisis, characterized by high electricity costs due to recent tax increases, subsidy removals, and the country's heavy reliance on imported fossil fuels. Frequent load shedding and persistent grid unreliability further underscore the urgent need for sustainable and locally optimized power solutions. This thesis presents comprehensive research on the design, modeling, simulation, and control of hybrid off-grid energy systems specifically tailored for urban residential neighborhoods in Karachi, Pakistan.
A novel architecture integrating distributed solar photovoltaic (PV) generation, battery storage, and a shared neighborhood diesel generator is proposed and validated. The primary goal is to deliver a cost-effective, low-maintenance, and grid-independent solution for reliable household electricity.
The study focuses on a residential site with seven houses, each with customized PV systems, supported by a shared diesel generator. Three complementary research stages are presented. First, optimal component sizing and techno-economic analysis using HOMER Pro identified ideal capacities for PV, batteries, and the generator, accounting for local solar resources and varied household demands (15−45 kWh/day). The optimized system minimized battery requirements, achieving a levelized cost of energy of 15,562.55.
Second, a detailed dynamic model in MATLAB/Simulink assessed system stability under changing solar and load conditions, confirming effective load response and rapid recovery from disturbances. Third, advanced control strategies coordinated diesel generator dispatch and balanced battery charging, ensuring reliable power delivery and preventing generator overload. This thesis establishes that the proposed PV–battery–diesel hybrid system is technically robust, economically viable, and effectively enhances urban energy resilience in Pakistan, providing a scalable and sustainable blueprint for addressing urban energy shortages
Understanding the effects of combined disturbances on eastern boreal forests using empirical and mathematical approaches
No full textThroughout eastern boreal forests, multiple anthropogenic and natural disturbances have influenced the forests’ ability to regenerate, with consequences for carbon storage, biodiversity and other ecosystem services. We examined responses of the boreal forest to the combination of gap forming disturbances (e.g., insect
defoliation, forest fires) and moose herbivory through empirical (Chapter 2) and
mathematical (Chapter 3) approaches. From our statistical models fit to field and remote sensed data, we found areas more likely to be gaps have lower carbon storage
and are characterized by forests with shorter vegetation and higher seasonality in
vegetation greenness. Furthermore, we provided evidence that moose may have
impeded the recovery of up to 13 megatons of carbon storage across our study area, 20-
30 years after disturbances. Our mathematical model of an eastern boreal forest provides additional evidence moose herbivory can impede regeneration of boreal forests. However, aspects of plant growth can interact with moose herbivory to ultimately determine whether a gap regenerates to boreal forest or transitions to
grassland. Our integration of statistical and mathematical approaches provides novel insights that may inform where forest gaps exist, why regeneration is important, and what needs to be done to restore mature boreal forest regeneration.Includes bibliographical reference
Sensory cortices in extinction and second-order conditioning: the construction of internal models of threat and safety
No full textThreat conditioning, extinction, and second-order threat conditioning (SOC), as studied in animal models, provide insight into the brain-based mechanisms underlying fear- and anxiety-related disorders and their treatment. However, the precise locations and molecular mechanisms of threat and extinction memories remain to be elucidated. Recent evidence suggests that the basolateral amygdala (BLA) functions as the core of a broader network of structures involved in affective learning, including associative and sensory cortices capable of acquiring the valence associated with stimuli and events. Accordingly, this dissertation investigates the potential role of the sensory cortices in the storage of extinction and second-order conditioning memories. In Chapter 2 we explore the potential for the olfactory posterior piriform cortex (pPC) to store olfactory threat extinction memories via a depotentiation mechanism, as well as age-dependent changes in this process. Olfactory threat extinction depends upon NMDA receptor (NMDAR)-dependent long-term depression (LTD) in the pPC, a process which is impaired with aging, and which can be rescued with NMDAR agonism, findings which may have important implications for our understanding of age-related cognitive decline. In Chapter 3 we explore the circuit- and molecular mechanisms of an auditory-olfactory SOC model. We demonstrate the role of the BLA and pPC in the encoding and retrieval of SOC associations, as well as the molecular mechanisms therein. We shed light on unique epigenetic and neuromodulatory requirements in the pPC at different time-points during SOC and provide evidence for a BLA-based SOC by consolidation mechanism. These findings expand our understanding of the sensory cortices as functioning beyond mere sensory processors to include the construction of extinction and higher-order threat memories, internal models of threat and safety
Clavam metabolite production in streptomyces: investigations into clavulanic acid and clavamycin biosynthesis
No full textStreptomyces are renowned for their ability to produce various bioactive compounds, such as antibiotics, antifungals, anti-tumor agents, and more. The clavam group of compounds include the clinically important ?-lactamase inhibitor clavulanic acid (CA) and the subgroup of antibiotics called the 5S clavams, both of which are produced by the organism Streptomyces clavuligerus. CA is industrially produced by fermentation of S. clavuligerus, during which a cluster of 16 genes that encode proteins and enzymes necessary for CA production are activated. The later steps in the CA biosynthetic pathway are not well understood, and the function of many of the gene products in the CA biosynthetic gene cluster (BGC) are unknown.
Orf12, also known as cpe (for cephalosporin esterase), is one of these genes of unknown function, and it has been shown in previous studies to be essential for CA production. It has been recently demonstrated that when cpe is overexpressed in S. clavuligerus, there is production of a 5S clavam in conditions that does not normally permit its production. In this thesis, I investigated these findings and attempted to uncover the role of cpe in CA biosynthesis by making the equivalent cpe knockout and overexpression strains in Streptomyces katsurahamanus, another CA producer. Additionally, I performed untargeted metabolomic analysis to assess the effects of cpe disruption and overexpression on global metabolite production. Finally, I conducted co-culture experiments of the S. clavuligerus cpe knockout strain with various other CA non-producer knockout strains. I report that cpe overexpression does induce production of 2-hydroxymethylclavam (2-HMC) through the activation of genes in the 5S clavam pathway and thus propose that CPE has a secondary role in pathway signaling, contributing to the tight regulation of antibiotic production in S. clavuligerus
Evaluating the effects of systemic mTOR inhibition on fear memory processes in rodents with relevance to ameliorating PTSD-like symptoms
No full textIn this dissertation, I use physical and psychogenic contextual fear conditioning procedures to study the role of the mechanistic target of rapamycin (mTOR) in memory processes and investigate its potential as a target for treating post-traumatic stress disorder (PTSD)-like symptoms in rodents. I determined that inhibiting both mTOR complex 1 and 2 with AZD2014 impairs the consolidation of a foot-shock induced contextual fear memory in mice similar to the mTORC1 inhibitor rapamycin, while inhibition of the mTORC1 downstream effector S6K1 with PF-4708671 does not. Using the same conditioning procedure, I found that rapamycin treatment three-hours, but not 12-hours, post-conditioning impairs the consolidation and persistence of contextual fear memory in mice. In support of earlier published work showing rapamycin impairs the consolidation of long-lasting contextual fear, hyperarousal, and anxiety-like behaviour in rats following a brief unprotected exposure to a cat, I show here, using immunohistochemistry, increased mTORC1 activation in the hippocampus and periaqueductal grey of rats shortly after this type of exposure. I also investigated the effects of psychogenic-only predator stress at inducing long-lasting behavioural changes via a model of mouse defensive behaviour previously unexplored for this purpose. Following a fully protected exposure to a rat, mice exhibited associative contextual fear and other non-associative fear and anxiety-like behaviours, with many of these behaviours weakened from post-exposure rapamycin treatment. In a different set of experiments using foot-shock conditioning, I reveal that rapamycin injected three- or 12-hours post-reactivation impairs the persistence of contextual fear memory, while the same treatment appears to induce a gradient effect against reconsolidation of the memory. Additionally, I demonstrate that two consecutive days of reactivation and rapamycin treatment maximizes abatement to recall foot-shock associated contextual memory through impaired
reconsolidation in mice. Lastly, I show that the effects of rapamycin to consolidation and reconsolidation on contextual fear memory in mice does not interfere with the ability to subsequently learn and recall new auditory fear associations but protects against fear generalization. Collectively, these findings advance our neurobiological understanding of mTOR in memory processes and provide preclinical evidence on how to pharmacologically treat PTSD-like symptoms.Includes bibliographical references (pages 128-185
Integrated gender and number agreement knowledge in French bilinguals
No full textTo better understand the performance of DP agreement processes in second language acquisition, this study investigates the processing of number and gender agreement in L2 French sentence reading. Eleven adult second-language French learners with English as a first language were tested in this study to determine the role of age of onset and proficiency in agreement representation and processing. The work specifically tested sensitivity to number and gender agreement errors during a self-paced sentence reading task. The findings highlight the effect of first-language influence in the processing of second-language structures that are specified in both languages. The findings found evidence of sensitivity to number agreement through longer reading times on errors involving number agreement, but no evidence of sensitivity to gender agreement. Additionally, there was no effect of the age of onset on processing and sensitivity patterns in either condition. However, proficiency was found to impact the processing of number agreement
Needs and preferences of cancer survivors in an insomnia treatment smartphone app
No full textBackground: Insomnia affects cancer survivors at a higher rate than the general population, impacting quality of life and physical health. Cognitive behavioural therapy for insomnia (CBT-I), the first-line recommended treatment for insomnia, is effective when delivered digitally through a smartphone app. However, no digital CBT-I program has been developed that addresses the unique needs of cancer survivors. The objective of this study was to understand the experiences of cancer survivors with regards to insomnia and insomnia treatment, while assessing their needs in an insomnia treatment smartphone app.
Methods: Cancer survivors meeting criteria for current or past insomnia responded to a digital questionnaire assessing demographic information, and cancer diagnosis and treatment history. Survivors then participated in one-on-one semi-structured interviews about their experiences with insomnia, smartphone use, and needs in an insomnia treatment app. Interviews were recorded and transcribed, and recurrent themes were identified using a process of thematic analysis.
Results: Twenty interviews were analyzed. All participants reported incidence or worsening of insomnia following cancer diagnosis or treatment. Smartphone CBT-I was considered acceptable by cancer survivors. Primary needs identified by cancer survivors for an insomnia treatment app included user friendliness, privacy and data security, and evidential basis.
Conclusion: Our results suggest that smartphone CBT-I is acceptable to cancer survivors, holding potential to greatly increase access to evidence-based insomnia treatment.Includes bibliographical references (pages 85-99
Technological change and an aging workforce: investigating the career experiences of older workers
No full textThis dissertation examines the intersection between two significant economic and societal challenges: an aging workforce and rapid technological change. The aging workforce is a growing concern, particularly in Canada, where the population of older workers (55 years and older) surpasses that of younger entrants (15 to 24 years). This demographic shift, already contributing to labour shortages in key sectors like manufacturing and healthcare, poses risks to labour participation rates and the stability of healthcare and pension systems (Acemoglu & Restrepo, 2017; Maestas et al., 2016). Given the projected exodus of older workers and limited incoming replacements, scholars and practitioners advocate for delayed or phased retirements to mitigate talent shortages. Simultaneously, technological change reshapes work, presenting opportunities and challenges, especially for older workers who may find adapting to new technologies daunting. This environment makes it critical to understand how technology affects older workers' experiences, including their retirement intentions. I conducted two studies to better understand the impact of technology and technological changes on older workers' work experiences.
In Study One, I conducted a systematic literature review to synthesize existing research on technology's impact on older workers, with a comprehensive analysis of 121 articles, including both peer-reviewed (n=82) and grey literature sources (n=39). Thematic analysis revealed key areas in the current literature, such as socio-demographic factors, training and development, and retirement planning. The results of this study also included descriptive insights on journals, methodologies, regions, and publication dates, highlighting 14 important research gaps. These gaps guided recommendations for future studies, which aim to address the implications of technological innovations on an aging workforce.
In the second study, I empirically examined the relationship between technological change and older workers' retirement intentions using a sample of 361 participants. Testing a moderated mediation model grounded in the Job Demand-Resources (JD-R) theory, I analyzed burnout and perceived work ability as serial mediators alongside moderating factors of computer self-efficacy, technological training, and organizational justice. Findings accentuate the complex interplay of burnout, work ability, and retirement intentions, emphasizing that burnout negatively impacts work ability, which in turn influences retirement intentions. Notably, technological training significantly moderated the relationship between burnout and work ability, reinforcing its role as an important factor shaping older workers' capacity to adapt within technologically evolving work environments. Ultimately, this dissertation provides valuable implications for both theory and practice. The findings from both studies provide important directions for the successful integration and retention of older employees in the rapidly changing technological work environment, as well as for creating a supportive work environment for them