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Sanctuaries of the Heart: Perception, Phenomenology and the Architecture of Salutogenic Healing
No full textThe thesis investigates the role of architecture as an active agent of healing by redefining salutogenic design through the lens of spatial phenomenology. It draws from the author’s own lived experience with mood disorders as well as extensive interdisciplinary research. The paper critiques historic, as well as modern healthcare approaches and treatment methods for mental health, with case studies such as Bethlem Royal Hospital and more sterile hospitals of today. In contrast, it studies the ancient healing methods that integrate the mind, body and spirit through spatial symbolism and rituals.
Additionally, the project incorporates Maggie Keswick Jencks’ diaries through the lens of Critical Discourse Analysis, to understand a patient’s perspective when they navigate healthcare facilities. The thesis further studies the impact of the diaries in the form of a detailed case study of the Maggie Centre. Other case studies also contribute to understanding nature, materiality and sensory experience which combine under the umbrella term of spatial phenomenology and often nurtures positive recovery. Central to this research is salutogenesis, an idea that can be reframed to fit in the architectural narrative. This results in a proposed design of a mental wellness facility, located on the banks of the Grand River, a site with rich history and ecological vitality. The design serves as a manifesto for salutogenic design, choreographing light, sound, scent, texture and time, it dissolves the Cartesian split between mind and body and creates a space which contributes actively in the healing process
Disaggregating Distributed PV Power From Aggregate Measurements in Transmission Systems
No full text(© 2025 IEEE) Safari, H., Cañizares, C. A., Sohm, D., Ahmed, E., El-Samahy, I., & Dusseault, M. (2025). Disaggregating distributed PV power from aggregate measurements in transmission systems. IEEE Transactions on Smart Grid, 16(6). https://doi.org/10.1109/tsg.2025.3596873The growing integration of Photovoltaic (PV) systems into distribution networks has limited visibility for system operators, as the power output of low-power PV systems is not typically monitored. The study presented in this paper introduces a novel approach for disaggregating PV generation from net-load measurements recorded at the transmission system level. The proposed technique is applied to actual data from an existing transmission line feeder to identify PV generation from net demand measurements. The developed methodology incorporates Geographical Information Systems (GIS) for detecting PV panels based on an algorithm that provides an accurate estimate of solar PV capacity. These estimations are validated against actual data from a local utility, showing a close match between the two. This information is then utilized in reliable software tools to simulate PV power generation in the studied region, which is then used to estimate and disaggregate the generated power from net-load data by applying multiple Machine Learning and Deep Learning models. The results demonstrate that, with the proposed approach, it is feasible to adequately disaggregate PV power generation from transmission feeder net-load measurements with minimal or no additional sensor infrastructure
Identifying the Relative Contribution of Motoric and Cognitive Engagement on Spatial Memory
No full textI investigated the cognitive mechanisms underlying spatial memory, with the aim of differentiating
the contributions of motor engagement and decision-making. In Experiment 1,
I examined whether volitional motor control or decision-making, during initial exploration
of a map within virtual reality, better supported retention of routes travelled. Participants
explored virtual cities under three navigation conditions that varied in terms of motor and
decision-making demands. During Active navigation, participants had volitional control
over their movement using hand-held controllers, allowing head and body rotation in a
swivel chair, and made independent decisions about which route to take to reach a target
location. During Guided navigation, participants still controlled their movement, but
followed a visually guided path overlaid onto the road, eliminating the need for decisionmaking.
In the Passive condition participants observed a pre-defined route without having
to make any decisions or engage motorically. Following exploration of each environment,
participants were asked to “re-trace their steps” using the exact route they had just traveled,
from the same starting point. Route memory was significantly better following Active
and Guided encoding relative to Passive, suggesting that volitional movement during navigation
underlay the benefit. Notably, the complexity of the path chosen by participant at
encoding did not predict accuracy of route memory. Experiment 2 assessed the necessity
of motor engagement and decision-making by comparing memory benefits following two
types of VR implementation: Desktop-VR, in which movement was limited to keyboard
input (lower motor engagement), and Headset-VR, in which participants navigated using a
steering wheel (higher motor engagement). An effect of navigation strategy emerged only
in the Headset-VR group: Active and Guided navigation at encoding led to significantly
better route memory relative to Passive. No significant differences emerged between Active
and Guided trials, suggesting that motoric engagement, rather than decision-making,
is the driver of memory performance. Interestingly, in Headset-VR, a stronger personal
preference for Active exploration predicted better route memory, whereas in Desktop-VR,
personal motivation predicted route memory accuracy. However, neither motivation nor
preference mediated performance, indicating that these factors did not account for the
effect of navigation condition on memory. If motor engagement contributes to the formation
of route memories, as suggested by experiments 1 and 2, then reduced mobility in
older adults may influence performance, and the components underlying it. At the same
time, reliance on landmark memory to guide memory may be heightened, as landmarks
provide salient external cues that could compensate for reduced motor-based encoding. To
test these predictions, in Experiment 3 I examined route and landmark memory in younger
and older adults as they explored virtual environments. In younger adults, both Active and
Guided navigation equally enhanced memory for routes compared to Passive, replicating experiments 1 and 2. However, in older adults only Active navigation, which engaged both
movement and decision-making, resulted in improved route memory. Further, landmark
memory in older adults benefitted the most from Active relative to Passive and Guided
navigation. Simply put, active encoding eliminated age-related deficits in route memory,
suggesting that decision-making (present only in this condition) during navigation may be
particularly important for supporting spatial memory in aging populations. This benefit
may reflect increased recruitment of frontal lobe-based resources during active navigation,
which can compensate for reductions in motor engagement. There were some differences in
motivation and preference ratings across conditions in both age groups. However, these subjective
measures did not emerge as significant predictors of memory performance. Overall,
my findings suggest that motor engagement plays a more critical role than decision-making
in enhancing subsequent route memory in younger adults, whereas conditions that require
decision-making benefit memory in older adults. These findings have important implications
for the design of navigational tools and cognitive interventions aimed at promoting
spatial independence, particularly among older adults
Signals of Legitimacy or Tools of Strategy? Investigating ESG Score Drivers in the Age of Sustainability Accounting Standardization, an Analysis of Canadian Firms
No full textESG scores
non-financial reporting
sustainability reporting
legitimacy theory
TSX firms
positive accountin
Advanced venous flow dynamics and return mechanisms during physiological stress and aging
No full textHuman veins are dynamic vessels responsible for managing return of blood to the heart. Unlike arteries, veins are structurally limited, creating exceptional hemodynamic susceptibility to hydrostatic forces and pressure generating forces. The precise extent of venous flow regulating mechanisms to these forces have implication for disease pathogenesis yet have been historically limited by technological tools. Thus, the purpose of this thesis is addressing the responses to hydrostatic volume stress, muscle pump activation and healthy aging through the piezoelectric lens of vector flow imaging ultrasound through a series of projects. First, progressive hydrostatic volume stress is applied to the internal jugular vein to address regional flow complexity and volume expansion behaviour. The internal jugular vein presented step-wise volume expansion in a trapezoidal shape and increasing flow complexity, increasing the risk for flow stasis and thrombus formation. Second, hydrostatic volume stress is used to compare artery-adjacent and non-adjacent veins to probe the existence of an arterial pump. During relevant hydrostatic driving forces, artery-adjacent veins demonstrated a preservation of venous flow, suggestive of a newly described mechanism of venous and an elegant conservation of mechanical energy within the cardiovascular system. Third, a comparison of younger and older adults leveraged differences in venous compliance to investigate flow complexity features during muscle pump activation during hydrostatic volume stress. Older adults were found to utilize their lower compliance to maintain venous ejection efficiency, whereas younger adults experienced great turbulence and vorticity flow features for the same venous outflow. Finally, venous valves were explicitly investigated during progressive hydrostatic volume stress and muscle pump activation to describe flow complexity features. Healthy valves generated efficient forward jets with downstream disturbed, low-shear zones, and volume stress amplified regional differences, underscoring the role of valve geometry in venous hemodynamics. Together, these studies establish new mechanistic links between venous structure, hydrostatic and muscle pump forces, and aging, advancing understanding of venous flow regulation and its implications for thrombotic risk and cardiovascular health
Cues, Clones, and Cars: Access Control Issues in Customized Android
No full textAndroid’s open-source design and extensive customization have fueled its dominance across smartphones, automotive systems, wearables, and other domains. This flexibility, however, introduces serious security challenges, particularly in the enforcement of access control. Prior research has investigated inconsistencies within the framework, across layers, and across Android versions, yet important gaps remain, especially in detecting vendor-introduced data-driven customizations, replicated APIs, and platform-specific adaptations (e.g., automotive) that are difficult to capture with existing techniques.
This dissertation investigates how Android contextual features can be systematically leveraged to uncover access control vulnerabilities that evade prior analyses. It presents four main contributions:
- Bluebird: a probabilistic inference framework that derives access control requirements from application-side sensitivity indicators (UI cues and app-side access control). By fusing NLP-driven signals with static analysis, Bluebird identifies APIs whose protections do not match implied sensitivity. Applied to 14 ROMs, Bluebird flagged 391 likely under-protected private APIs.% and supported 11 proof-of-concept exploits.
- Ariadne: a static-analysis based technique built around a novel access control dependency graph abstraction that models explicit and inferred access control relationships among framework data holders. Ariadne detects inconsistencies introduced by data-driven vendor customizations that traditional tools miss. Evaluated on AOSP and vendor ROMs, it discovered 30 unique inconsistencies and enabled 13 proof-of-concept exploits.
- RepFinder: a large-scale measurement pipeline that identifies duplicated or ``Replica'' APIs created via copy-paste editing and evaluates their access control enforcement. Analyzing 342 ROMs from 10 vendors, RepFinder found replication to be widespread (~141 Replicas/ROM on average) and that a significant fraction (37% on average) of Replicas are under-protected.
- AutoAcRaptor: a platform-specific static analysis framework for AAOS that identifies automotive entry points and evaluates both access control and feature-check enforcement. Applied to 10 AAOS ROMs, AutoAcRaptor reported an average of 23 auto feature and access control anomalies per ROM.
Collectively, these contributions show that Android contextual features such as app-side sensitivity indicators, framework data holders, and platform-specific service registrations can be systematically harnessed to reveal overlooked access control vulnerabilities. They also demonstrate that techniques for identifying framework customization-induced vulnerabilities can be adapted to emerging Android-based platforms such as Android Automotive OS by accounting for platform-specific differences.
Beyond these immediate contributions, this work opens two broader research directions. First, the contextual features explored in this work may not be exhaustive. Future research should aim to identify additional contextual signals—potentially through automated discovery—and explore an integration framework that makes it easy to incorporate new analyses into a unified solution. Second, the adaptation of these techniques to other Android-based platforms remains an open challenge. While AutoAcRaptor demonstrates feasibility for Android Automotive, other platforms such as Android TV, Wear OS, and Android XR present unique differences that require dedicated investigation to determine how well these methods generalize and what extensions are needed
The Effects of Reward Nature and Reward Contingency on Employee Voluntary Training
No full textDespite firms investing billions of dollars in voluntary training, employees’ skills still fall behind what firms need. Therefore, managers must motivate employees to allocate more effort toward voluntary training. In a multi-task setting where effort allocated to both production and voluntary training can increase employee performance, I examine how two attributes of performance-based rewards – reward nature (hedonic vs. utilitarian) and reward contingency (goal-based vs. piece-rate) – affect employee total effort, voluntary training effort proportion, and performance. Using a lab experiment, I find that the effect of hedonic (vs. utilitarian) reward nature on employee total effort is more positive when the reward is goal-based than piece-rate; the effect of hedonic (vs. utilitarian) reward nature on employee voluntary training effort proportion is more negative when the reward is goal-based than piece-rate; and the effect of hedonic (vs. utilitarian) reward nature on employee performance is more positive when the reward is goal-based than piece-rate. These results inform managers of the need to consider reward nature and reward contingency together in reward design: adjusting the reward nature is likely more useful in balancing employees’ production effort and voluntary training effort for jobs where goal-based rewards are offered than for jobs where piece-rate rewards are offered. Utilitarian reward nature can motivate employees to allocate more time to training than hedonic reward nature when the reward is goal-based; however, reward nature matters less when the reward is piece-rate
Youth Lived Experiences in High-Rise Housing: Implications for Health and Urban Planning
No full textContinued global urbanization and the growth of high-rise residential development have increasingly shaped the environments in which young people live. Although related areas of study have examined how built, natural, and social environments influence youth well-being, the health implications of high-rise living for youth remain poorly understood. In the present study, small semi-structured focus groups (2-4 participants) with 19 youths aged 13-18 were conducted, lasting between 63 and 86 minutes. Each focus group was recorded, transcribed, and analyzed using the Framework Method to identify recurring themes. Five themes were developed: Safety and Security; Public Space Design and Accessibility; Social Inclusion and Participation; Economic and Structural Barriers to Youth Needs; and Physical and Mental Health. Youth described both positive and negative experiences within high-rise and high-density environments, associated features such as clean public spaces, social infrastructure, and recreation areas with positive well-being; whereas they identified homelessness, drug use, and poor lighting negatively, which led to avoidance of certain public spaces. A central theme that emerged from the data was youth perceptions of safety and social disorder, indicating that challenges in high-rise environments extend beyond planning and design but also relate to social and environmental conditions. The study contributes to understanding how youth experiences can inform more inclusive and healthier high-rise urban environments
Total Synthesis and Stereochemical Assignment of Turnercyclamycin C
No full textTurnercyclamycins (TCMs) are a new family of cyclic lipopeptide antibiotics (cLPAs) isolated from Teredinibacter turnerae, a symbiont of shipworms. They contain thirteen amino acids, eight of which are contained in a macrocycle closed by an ester bond. Attached to the macrocycle is a linear pentapeptide that is lipidated at the N-terminus. The four members of this family, TCM A to D, only differ from one another in their lipid tail composition. Seven of the thirteen amino acids are non-proteinogenic: D-ornithine, D-threo-β-hydroxyaspartic acid (D-t-HOAsp), D-threo-β-hydroxydiaminobutyric acid (D-t-HODab), L-β-hydroxyisoleucine (L-HOIle), two D-allo-isoleucines (D-allo-Ile) and L-homoserine (L-hSer). Their mechanism of action (MoA) is unknown. The TCMs exhibit good activity against Gram-negative pathogens Escherichia coli, Klebsiella pneumoniae and Acinetobacter baumannii (A. baumannii) including colistin-resistant A. baumannii suggesting that the TCMs act by a MoA that is different from colistin. These findings and the favourable pharmacokinetic properties displayed by the TCMs suggest that they may be good leads for the development of a novel antibiotic for treating colistin-resistant A. baumannii via a unique MoA. The total chemical synthesis of the TCMs has not been achieved and the configuration at the -carbon of L-HOIle is unknown. Here, our efforts to develop a total chemical synthesis of one of the TCMs, TCM C, which has a dodecanoyl fatty acyl tail, are described. These efforts began with the synthesis of D-t-HOAsp, D-t-HODab, and both stereoisomers of L-HOIle, suitably protected for Fmoc solid phase peptide synthesis (SPPS) using both literature and novel routes. Before synthesizing TCM C, an analogue of TCM C, called TCM C-CA, in which we substituted D-t-HODab for D-Dab, D-t-HOAsp for D-Asp and L-HOIle for L-Ile was prepared. This was achieved using Fmoc SPPS in an overall 5% yield. This synthesis provided valuable information on how to best perform some of the key steps such as ester bond formation and macrocycle formation without using up the valuable non-canonical amino acids prepared by chemical synthesis. The synthesis of two versions of TCM C, each one containing one of the two stereoisomers of L-HO-Ile, is in progress
Evaluating Face Mask Efficiency on Children and Adults
No full textSmall infectious aerosols have been a major vector for the spread of diseases such as COVID-19 and influenza. During the recent global pandemic, masking played a key role in reducing airborne transmission, although significant variability has been noted in the ability of different mask types to limit pathogen-laden aerosol dispersion and inhalation. Moreover, there remain significant gaps in the literature regarding mask performance for children. The aim of this thesis is to characterize mask inward protection efficiency for both children and adults, and source control efficiency for children in the 0.2 μm to 1 μm particle size range.
An approach based on the conservation of mass guided the experimental methodology used to estimate mask filtration characteristics. For all tested masks, the material filtration efficiency was measured to be at or near 100%, whereas fitted filtration efficiencies for both source control and personal protection were significantly lower. This disparity underscores the highly degrading effects of leakage from gaps at the mask-face interface.
Inward protection efficiency of N95, KN95, and surgical masks donned regularly and using the tie and tuck method were estimated on a medium NIOSH adult head form. The tested N95 barrier provided the greatest protection, followed by the KN95 respirator, while the surgical masks offered the least protection. Use of the tie and tuck for surgical masks method yielded only a small, statistically insignificant improvement in inward protection compared to regularly worn variants. Incorporating results from broader literature, mean inward protection efficiency ranges of [67.9%,100%] and [12.5%,79.6%] were determined for the N95 and regularly worn surgical masks, respectively.
Both inward protection and apparent filtration efficiencies of adult, modified adult, and child variants of the KN95, CA-N95, and surgical mask as well as the N95 respirator, were estimated on a child manikin. Results further underscore the critical importance of proper fit to mask performance. Child-sized respirators provided higher source control and personal protection compared to other barriers tested. In contrast, the adult-sized surgical mask, which exhibited a loose fit on the child manikin, demonstrated poor performance in both metrics due to the highly degrading effects of leakage. Overall, whenever both variants are available, adult-sized masks demonstrate markedly reduced fitted efficiencies on the child manikin relative to child-sized variants, attributed to larger gaps at the mask-face interface. Flow visualization of air exhaled through the tested barriers qualitatively corroborated these findings, revealing substantially reduced leakage for child-sized variants compared to adult-sized equivalents.
Given the increased sensitivity of children to mask breathing resistance, pressure differentials measured across masks donned on the child head form provided relative indicators of breathability. Results demonstrated that masks with similar filtration efficiency can exhibit significant differences in breathability. For example, the child-sized CA-N95 achieved equal or greater fitted filtration efficiency while consistently maintaining lower pressure drops compared to the child KN95. In fact, KN95 respirators showed differential pressures greater than or equal to those of all other tested masks. For a given mask type, better fit was associated with higher differential pressures. However, across different mask designs, higher filtration efficiency did not necessarily compromise breathability