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Feature Pyramid Optimization-Based Small Object Detection in UAV Imagery
No full textUnmanned Aerial Vehicles (UAVs) are increasingly used in key applications such as surveillance, search and rescue. However, due to the small scale of objects, cluttered backgrounds, and inherent information loss, accurate object detection from a high-altitude perspective is still a major challenge. Although two-stage detectors can provide high accuracy, their high computational costs are not suitable for real-time edge deployment. In contrast, the most advanced single-stage detectors, such as YOLOv10, often fail to capture small objects because the deep pyramid structure loses key spatial details in the downsampling process. In order to overcome these limitations, this paper proposes a systematic optimization framework for small object detection in high-altitude imagery. We first introduce FemtoDet-P2, which combines the MambaOut backbone network with a high-resolution P2 detection head. As a high-precision baseline, this architecture verifies that strengthening early feature extraction is crucial to solving the problem of feature vanishing, even if structural redundancy is introduced. Based on this, we propose LSCNet to balance the trade-off between detection accuracy and computational efficiency. LSCNet eliminates the redundancy in the baseline model and enhances multi-level feature fusion by constructing a shallow feature cascade and introducing a lightweight attention mechanism. This lightweight design ensures that advanced deep learning models can be efficiently deployed on resource-constrained UAV platforms without compromising their ability to identify small objects in complex environments
Medical Dominance and the Governance of Quality: Strategic Adaptations to Performance Measurement and Feedback in Orthopaedic Surgery
No full textBackground: This thesis investigates how orthopaedic surgeons interpret, adapt, and respond to continuous quality improvement (CQI) systems in everyday practice, using the Adverse Event Performance Measurement and Feedback (AE-PMF) tool as a case example. Drawing on sociological theories of medical dominance, evidence-based medicine (EBM), and audit and feedback, it explores how data-driven accountability mechanisms are received, negotiated, and reshaped within the professional norms, institutional contexts, and collegial dynamics of surgical care.
Methods: A qualitative case study was conducted in a single orthopaedic surgery division in Ontario. Data collection included semi-structured interviews with surgeons and clinical leaders, along with analysis of institutional documents related to CQI. Thematic analysis was used to examine how participants engaged with CQI practices, particularly the implementation and perceived utility of the AE-PMF tool.
Results: Surgeons did not passively adopt CQI tools but strategically reframed them to preserve clinical authority. They engaged selectively with quality initiatives—developing localized protocols, leveraging collegial networks, and navigating audit systems in ways that aligned with professional judgment. Collegiality served as a key mechanism of internal accountability, while transparency efforts, intended to promote oversight, often reinforced existing hierarchies. Adverse events were not objectively reported but socially constructed through peer negotiation, reputation management, and contextual discretion.
Discussion: The findings demonstrate that audit and feedback tools like AE-PMF are not neutral instruments, but sociopolitical artefacts embedded in professional power dynamics. CQI systems both challenge and sustain medical dominance—limiting autonomy in some cases while enabling its strategic preservation in others. This study contributes to the sociology of health care by showing how performance measurement is shaped by cultural norms, professional discretion, and peer governance.
Conclusion: To be effective, CQI systems must move beyond compliance-based models and account for the interpretive, relational, and institutional realities of clinical work. Tools like AE-PMF should foster reflective learning and shared accountability rather than symbolic oversight. Recognizing surgeons as active agents in defining and enacting quality is essential for building contextually meaningful and sustainable CQI frameworks
Companions on the Way: Sufism in 21st Century Oakland, California
No full textThis project explores the religious philosophy, pedagogical practices and story of Mahmoud Malamatian, an Iranian-American Sufi teacher who practices in present-day Oakland, California. I have known Mahmoud, his wife Rozaneh and their family for eight years. To honour my proximity to the 'subject,' I employed a Lived Religion theoretical framework and gathered data using the qualitative autoethnographic research method.
This dissertation highlights three themes in particular, (1) Mahmoud's pedagogical approach for teaching Sufism, (2) his lack of affiliation with any religious institution, and (3) Sufi tabaqat, a genre of Islamic and Sufi biographical manuals. The tabaqat serve as a tool for historically and religiously contextualizing, as well as defining Mahmoud's philosophy and practices. In particular, I consulted the tabaqat of the medieval Persian Sufi masters Sulami (d. 1034), Hujwiri (d. 1077) and Qushayri (d. 1072/3) and the work of Sufi poets and storytellers like Rumi (d. 1273) and Attar (d. 1221).
This autoethnographic case study of contemporary Sufism, focusing specifically upon Mahmoud's philosophy, pedagogy and practices, explores these themes in the context of six specific subjects: Sufism generally; love (muhabba; ishq); lineage and transmission (silsilah); adab and companionship; storytellers and stories in Sufism; and gender and power. Ultimately, this work provides a window into a contemporary expression of Sufism that is profoundly traditional but adapted for its time and place
Investigation of Inoculation Routes on Chronic Wasting Disease Progression in Cervidized Mouse Model: A Foundation for Microbiota-Pathogenesis Research
No full textChronic wasting disease (CWD) is an infectious and fatal prion disorder of cervids that is rapidly expanding across North America. Although extensively studied in natural hosts, the early tissue and route-specific events that govern prion seeding and amplification remain poorly defined. This thesis employed transgenic mice that express transgenic elk prion protein (TgElk) to investigate the effects of inoculation routes on CWD prion seeding and distribution in selected tissues.
TgElkPrP mice were inoculated with CWD positive brain homogenate via the intragastric (IG) or intracerebral (IC) routes. Prion seeding activity and amplification were determined using real-time quaking-induced conversion (RT-QuIC), and the CWD positivity in animals was confirmed by immunohistochemistry.
Prion seeding activity was detected in brain and spleen tissues as early as 8 weeks post-IC inoculation. In contrast, prion seeding activity was minimally expressed in mice by 56 weeks post-IG inoculation, suggesting a longer incubation time is required for disease manifestation. These findings indicate differential disease progression rates and incubation processes caused by different inoculation routes.
This work also provides a foundation for future investigations into the interaction between CWD progression and the dynamics of gut microbiome composition, with the potential to identify gut microbial species as a biomarker for early detection of CWD and to understand how gut microbial communities influence animal susceptibility to CWD
Expanding access to HPV screening through community health insurance schemes: lessons from a screening exercise for teachers in Ghana
No full textAbstract Background Cervical cancer (CC) screening uptake remains low primarily owing to the absence of organized screening and lack of insurance coverage. Members of the Ghana National Association of Teachers (GNAT) contribute monthly to an insurance scheme which covers cancer (including CC) treatment but not cervical precancer screening/treatment. We conducted this study to examine health beliefs shaping cervical screening uptake among educators and to understand how the scheme could scale cervical precancer screening and treatment services for beneficiaries across the country. Methods From February − July 2022, we performed cervical precancer screening with concurrent hr-HPV DNA testing and visual inspection with acetic acid (VIA) for 102 teachers in 3 districts in the Volta Region. From April − May 2024, we conducted a cross-sectional study among 498 female subscribers of the GNAT insurance scheme in the same districts using non-probability snowball sampling. Data on utilization of cervical cancer screening services and risk factors were collected using a self-administered questionnaire. Health beliefs and situational factors associated with screening uptake among school teachers were assessed. Results Although all 498 female school teachers were enrolled in the cancer insurance scheme, cervical cancer screening uptake was reported by 116 (23.9%). Utilization of cervical cancer screening services was 25.3% among married women and 34.4% among women who reported limited access to screening. In the final adjusted logistic regression model, perceived barriers to screening (aOR, 0.55; 95% CI, 0.42 − 0.72) and being divorced/widowed (aOR, 2.11; 95% CI, 1.10–4.03 vs. married/cohabitating) were independently associated with cervical precancer screening uptake. The hr-HPV prevalence and VIA ‘positivity’ rate were 17.3% (95% CI, 9.9–24.8) and 1.0% (95% CI, 0.0–5.5), respectively. Conclusions Cervical precancer screening utilization among female teachers enrolled in the GNAT cancer insurance scheme was sub-optimal owing to barriers related to low awareness, limited access, and social factors. The cancer insurance scheme represents a golden opportunity to overcome the identified barriers and improve HPV screening access and outcomes in addition to increasing access to cervical cancer treatment and should be explored
Improving care for intimate partner violence in the emergency department: recommendations from a Canadian retrospective chart review
No full textAbstract Background Intimate partner violence (IPV) is prevalent among patients visiting the emergency department (ED). Studies show that patients experiencing IPV continue to have negative care experiences in the ED, leading to an increased risk of adverse physical, mental, legal, and economic outcomes. However, few studies explore ED care metrics and gaps in knowledge on how providers can improve. Methods We sought to fill these gaps by collecting quantitative and qualitative electronic data on ED care parameters for patients experiencing IPV. A retrospective chart review was conducted for patients seen in our tertiary care center’s ED and by our Sexual Assault and Domestic Violence Program between December 17, 2018 and June 16, 2021. Quantitative data, including sociodemographics, were summarized using medians/interquartile ranges and frequencies/proportions as appropriate using SPSS. This paper describes IPV care metrics across three domains: (1) ED mandatory reporting, (2) medical management of strangulation, and (3) discharge diagnosis containing IPV. Additionally, when documenting IPV encounters in charts, the use of trauma- and violence-informed care (TVIC) principles was evaluated as a secondary exploratory outcome. Results A total of 124 clinical encounters were analyzed. Among these, 54 involved children in the home, and documentation of mandatory reporting was absent in 43% (23/54) of such cases. Twenty-five patients experienced strangulation; however, 88% (22/25) of these cases were inadequately investigated. Furthermore, IPV was omitted as a discharge diagnosis in 38% (47/124) of encounters. Overall, 64% (79/124) of charts demonstrated a lack of trauma- and violence-informed care (TVIC) principles in the documentation of IPV-related encounters. Conclusions These findings highlight that gaps exist for ED patients experiencing IPV and illuminate areas for improvement of clinical care. We provide evidence-based recommendations for ED providers to improve their management of IPV, including review of mandatory reporting legislation, overview of clinical criteria requiring contrast imaging for strangulation, and discussion around the significance of including IPV in ED discharge diagnosis. Clinical trial number Not applicable
1,1,3,3-Tetramethyldisiloxane and Potassium Tert-Butoxide as an Unconventional Reducing Agent and its Application in the Synthesis and Deconstruction of Carbon-Carbon Bonds
No full textOver the past decade, the combination of hydrosilanes and Lewis bases have seen a renaissance with chemists uncovering the mechanistic intricacies that underlying their reactivity. Owing to the diverse mechanistic reactivity showcased by these reagent combinations, various reductive defunctionalization reactions including C-O, C-N, and C-C bond cleavage have been reported as practical synthetic methods. Further investigation of these reagent combinations led to the development of C-H and N-H silylation reactions in addition to hydrosilylation reactions earning their place as versatile synthetic multi-tools. Despite this synthetic versatility, chemists have yet to extend the list of transformations facilitated by hydrosilanes and Lewis bases to the synthesis of carbon-carbon bonds - a fundamental transformation in organic synthesis. This thesis outlines the discovery and application of 1,1,3,3-tetramethyldisiloxane (TMDSO) and potassium tert-butoxide (KOᵗBu) as a unique reducing agent towards C-C bond cleavage and C-C bond formation.
Chapter Two of this dissertation outlines the serendipitous discovery and development of the reductive C(sp²)-CF3 bond cleavage of 2-trifluoromethylpyridines. Using TMDSO and KOᵗBu the reductive cleavage of C(sp²)-CF₃ bonds was demonstrated to be regioselective for C2 on trifluoromethylpyridines and trifluoromethylquinolines bearing alkyl, amino, aryl, and chloro substituents. A small mechanistic investigation unveiled that TMDSO and KOᵗBu may display redox reactivity acting as a one-pot single-electron donor and hydrogen atom donor. The discovery of this redox reactivity manifold culminated in a hydroalkylation reaction discussed in chapter 3 of the dissertation.
Chapter Three of this dissertation builds on a discovery made towards the end of Chapter Two where under the same reaction conditions trans-stilbene could be hydroalkylated using an alkyl halide as an electrophile, representing the first instance of C(sp³)-C(sp³) bond formation facilitated by the combination of a hydrosilane and Lewis base. This transition-metal-free approach is used to functionalize mono, di, and trisubstituted aryl olefins bearing alkyl, aryl, and halogen substituents and primary and secondary alkyl halides as electrophiles. An in-depth mechanistic analysis pointed towards the formation of a benzylic radical via HAT from what is presumed to be a potassium dihydridosilicate to styrene, followed by a key reductive radical polar crossover step to transform the benzylic radical into a benzylic carbanion. A subsequent bimolecular nucleophilic substitution reaction between the benzylic carbanion and alkyl halide leads to the desired product.
Chapter Four of this dissertation highlights an unusual C(sp³)-H alkylation reaction facilitated by TMDSO and KOᵗBu that was discovered at the end of chapter three. In this chapter, TMDSO and KOᵗBu are used to facilitate the deprotonation and alkylation of weakly acidic C(sp³)-H bonds. A small scope of alkylpyridines, benzylic species, and dithiane were amenable to the reaction conditions. A unique feature of this reaction is the overalkylation of the intended product thought to occur through a subsequent deprotonation and alkylation step; this reactivity was exploited to synthesize novel spirocycles from alkylpyridines and dihaloalkanes. Control experiments, reaction kinetics, and substrate probes revealed the reaction proceeds through a key deprotonation step facilitated by a KH-like base derived from the hydrosilane, TMDSO.
This thesis concludes with chapter five highlighting the significance of this work by demonstrating the expansion of hydrosilane and Lewis base reactivity towards the synthesis of C(sp³)-C(sp³) bonds. This chapter also serves to frame the future of this reactivity based on the opinions of the dissertation author
Social Media Literacy in the Iranian Population Regarding Health Information in the Context of the COVID-19 Pandemic
No full textMedia literacy plays a pivotal role in combating misinformation related to health on social media platforms. This mixed-method thesis explores the level of social media literacy among the Iranian population regarding health information amid the COVID-19 pandemic. The research employed both quantitative and qualitative approaches: a public survey based on the UNESCO media literacy framework, and interviews with media experts.
The quantitative phase consisted of a 113-question survey, which received 38 final responses from the public. In the qualitative phase, ten media experts were interviewed to interpret the survey results and discuss potential strategies to enhance media literacy.
Findings revealed a significant discrepancy between the public's self-assessed media literacy and the experts' evaluations. Factors such as gender, education, and age did not significantly affect media literacy levels within the studied group. However, trust, generational gaps, and cultural values were found to influence the development of media literacy.
The COVID-19 pandemic presented opportunities to address media literacy challenges. Based on the research findings, several recommendations are provided for designing effective programs and strategies tailored to Iranian social media users. Recognizing the illusion of knowledge and the gap between public perception and expert assessment is crucial for effective intervention.
Improving media literacy can help Iranians avoid health-related misinformation on social media. Furthermore, this study offers a roadmap for identifying which areas of social media literacy require immediate attention and serves as a pilot for broader research into the impact of cultural, religious, and political factors on media literacy
High Spectral Resolution Chirp Modulation Stimulated Raman Scattering Microscopy
No full textStimulated Raman scattering (SRS) microscopy enables rapid, chemical-specific, label-free imaging and is a powerful technique for bioimaging and material characterization. In spectral focusing SRS, the two input laser pulses are linearly chirped and delay-scanned, providing rapid tunability while preserving Raman spectral resolution. Conventional linear modulation-transfer detection schemes commonly used in SRS, however, can be challenged by non-Raman backgrounds. Leveraging the quadratic phase control inherent to spectral focusing SRS enables Chirp modulation (CM)-SRS, a modulation transfer technique based upon modulating only the sign of the linear chirp. CM-SRS cancels all non-Raman signals while retaining a quantitative, highly sensitive Raman response. Motivated by these advantages, we designed and implemented an updated CM-SRS setup optimized for maximal background subtraction. Achieving both high spectral resolution and quality chirp matching in spectral focusing CM-SRS requires fine control over the pulse chirps at the microscope sample plane. To this end, we developed Fringe-averaged collinear Frequency-resolved optical gating (FRACOL-FROG), a robust method for in situ characterization of the input laser fields. Together, these advances position our CM-SRS microscopy system to deliver high-resolution, background-free, chemical-specific, and high-sensitivity measurements across a range of important samples previously challenged by background signals
Branching Rules for Irreducible Smooth Representations of Unramified U(1,1)
No full textLet G = U(1,1) denote the group of F-points of the quasi-split E/F-form of GL₂, where F is a non-archimedean local field of residual characteristic p ≠ 2, and E is the quadratic unramified extension of F. In this thesis, we determine the branching of almost all irreducible smooth representations of G upon restriction to a fixed maximal compact subgroup K. We prove that each such restriction decomposes as a multiplicity-free direct sum of irreducible components of distinct depth and degree, up to twisting by a quasi-character of G. Moreover, we give an explicit description of all irreducible components that occur in this decomposition in terms of irreducible representations of K constructed herein.
We analyze the branching rules by dividing the irreducible representations of G into three classes: depth-zero supercuspidal representations, positive-depth supercuspidal representations, and principal series representations. We provide two applications of this explicit description. First, we show that the higher-depth components arising in these decompositions exhibit a striking uniformity: up to twisting by a quasi-character of G, they coincide with the higher-depth components obtained from a fixed collection of four depth-zero irreducible supercuspidal representations. Second, we prove that the restriction of irreducible representations of G to a smaller subgroup of K can be described entirely in terms of the trivial representation and certain representations arising from nilpotent orbits in the Lie algebra of G, thereby establishing a new case of a recent conjecture in the literature