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Responsibility for Online Harms: A Critical Analysis of Cyber Governance in Saudi Arabia
No full textThis thesis investigates the topic of internet governance within the context of Saudi Arabia. It focuses on the component of ‘Responsibility’ for internet governance when applied to the policy area of combating online harms. As such, the research work investigates and evaluates the present framework of responsibility devised to address online harms, considering the assemblage which regulates online content and cybersecurity in the Kingdom of Saudi Arabia. This approach aims to facilitate the prevention and mitigation of the harmful effects of online activities and content, thereby aligning with the objectives outlined in the Saudi state’s long-term project known as Vision 2030. The thesis adopts the hypothesis that effectively addressing online harms requires a primary objective of establishing a robust responsibility structure. This method can best be achieved by facilitating the active participation of all stakeholders in the strategic deployment of responsive – including preventive – measures. Consequently, the thesis advocates a multistakeholderism approach with reference to governance for the prevention and mitigation of online harms in Saudi Arabia. It evaluates the effectiveness and fairness of the responsibility structure in fostering cybersecurity and mitigating the harmful effects of online content in the Saudi context. The formal study employs semi-structured interviews with elite figures and authorities from governmental and private organisations, internet content and service providers, as well as corporate users, which are the small and medium enterprises (SME) as internet users. Additionally, it integrates the policy transfer methodology to draw insights from the experiences of the United Kingdom in the realm of internet governance. In sum, the thesis proposes areas of improvement to develop a comprehensive online harms governance framework in Saudi Arabia. Such amendments are expected to contribute to the recognition and realisation of the declared Vision 2030 goals related to internet governance in the Saudi realm
Investigating spinal biomechanics and mechanobiology to predict disease progression and treatment effects in oncology patients.
Get PDFPrimary cancers, such as prostate cancer and multiple myeloma (MM), frequently metastasise to the skeleton, disrupting bone remodelling, reducing vertebral strength, and increasing fracture risk. As treatments extend survival, more patients are living with structurally compromised vertebrae. To assess the vertebral strength in cancer patients using clinical CT scans, a finite element (FE) pipeline was first developed. Its development highlighted the impact of image quality on segmentation reproducibility and showed comparable results between phantom and phantomless calibration methods.
In Chapter 4, the effect of androgen deprivation therapy (ADT) on vertebral strength in prostate cancer patients was investigated using a combination of DXA-derived areal bone mineral density (aBMD), CT-derived volumetric BMD (vBMD), and mechanical properties from the FE pipeline. Significant reductions in densitometric and mechanical properties were found after 12 months of ADT. Furthermore, vBMD outperformed aBMD in predicting vertebral strength, suggesting that these clinically accessible measures may better assess fracture risk.
Chapter 5 applied the FE pipeline to MM patients treated non-surgically. Changes in CT derived densitometric and FE-derived mechanical properties over time were quantified. In vertebrae with large lesions (>50% of the vertebral body), remineralisation around the lesion was observed, resulting in increased strength. To investigate the mechanisms behind this, a mechanobiological model was developed in Chapter 6. This multi-scale model combined organ-level FE simulations with a cell-level bone adaptation algorithm and was optimised for each patient. While the model accurately predicted mineral and strength changes in vertebrae with smaller lesions, it failed in vertebrae with extensive lesions, suggesting that standard bone remodelling principles are insufficient in myeloma-affected bone. Additionally, its reliance on longitudinal scans limited its prospective use.
To enable prospective use, Chapter 7’s pilot study incorporated serum bone turnover markers at 1, 2, and 3 months into the mechanobiological model, allowing for successful prediction of 12-month mechanical outcomes in 3 out of 5 patients from baseline imaging alone. This biomarker-informed model marks the first use of biomarkers to drive personalised vertebral strength prediction. Together, these innovations offer a foundation for improved treatment monitoring, early fracture risk prediction, and decision-making in metastatic bone disease
Monitoring Surface Deformation in Ecuador with InSAR: Insights into Tectonic, Volcanic, and Anthropogenic Processes
No full textGeodetic measurements, encompassing GNSS and InSAR technologies, are pivotal in understanding Earth's surface deformation and evaluating natural hazards. This thesis focuses on the intricate tectonic, volcanic, and anthropogenic processes shaping Ecuador’s surface deformation, driven by the Nazca plate's subduction beneath the South American plate. Ecuador’s complex tectonic framework, including active fault systems and volcanic arcs, presents a unique challenge for deformation monitoring. The integration of GNSS and InSAR data provides a comprehensive approach to understanding these phenomena, addressing challenges posed by diverse land and vegetation cover, decorrelation, and regional geological intricacies.
Here, I use radar (SAR) data from the European Space Agency's (ESA) Sentinel-1 C-band satellite to generate a line-of-sight time series and measure displacements across Ecuador in both ascending and descending tracks. First, I analyzed deformation signals in Ecuador's inter-Andean valley between 2017 and 2023, identifying processes such as urban subsidence, resource extraction impacts, fault activity, and volcanic deformation. Major findings include geodetic slip and strain rate estimates for the Chingual-Cosanga-Pallatanga-Puna fault system, highlighting its active branches and potential hazards. Furthermore, my study reveals sustained uplift at Volcán Sangay during its recent eruption (2019–2022), attributed to magmatic volume increases beneath its western flank.
Finally, with advanced InSAR techniques and blind source separation methods, I analyzed a decade of satellite radar imagery to isolate deformation sources across 21 mainland Ecuadorian volcanoes. The results yield tailored monitoring strategies for individual volcanoes, capturing magmatic and non-magmatic signals. These findings underscore the potential of satellite radar data for country-wide volcanic monitoring and contribute valuable insights into Ecuador’s dynamic geophysical landscape, offering frameworks applicable to similar Andean settings and this research emphasizes the critical role of integrated satellite radar and GNSS analysis in advancing geohazard monitoring and resilience strategies
A mixed methods study in cystic fibrosis following the widespread availability of elexacaftor/tezacaftor/ivacaftor. Understanding the impact of context change in long-term condition care
Get PDFThis study explored how the introduction of elexacaftor/tezacaftor/ivacaftor (ETI) has
shaped cystic fibrosis (CF) care. This pragmatic, mixed-methods Realist Evaluation
examined how clinicians and people with CF (pwCF) made sense of and responded to
this contextual change, focussing on adherence to inhaled medicines and the evolving
configuration of specialist CF services.
Initial Programme Theory was developed through interviews with CF clinicians across the
UK. It was refined through a national survey and realist focus groups with pwCF. Feasible
elements of Programme Theory were tested in a multivariable regression analysis.
The refined Programme Theory identified key mechanisms shaping post-ETI care.
Restored wellness has led pwCF and clinicians to re-evaluate the role of burdensome
inhaled medicines and models of care. Many pwCF feel empowered to autonomously
reduce inhaled medicines, giving primacy to subjective health indicators, such as
symptom burden. In the absence of published evidence, many clinicians are hesitant to
support these approaches. Clinicians often prioritise objective health indicators, such
as lung function, over subjective measures. The resulting epistemological dissonance
between pwCF and clinicians leads to concealment of actual behaviour, uncertainty,
and variation, leaving some clinicians feeling professionally disempowered. While some
pwCF find adoption of virtual appointments liberating in the context of improved health,
others experience abrupt transitions as abandonment, highlighting the enduring
importance of relational continuity.
These findings reinforce the need for shared decision-making and personalised care in
the post-ETI era. Ten recommendations aim to guide service design, including an
acknowledgement of emotional and relational needs, adoption of shared decision-
making, and a more holistic model of care. As the first Realist Evaluation in CF, this thesis
provides novel insights into the generative mechanisms underpinning behaviours. It
introduced the PLUTO framework to support shared decision-making and emphasised
habit as key mediator of adherence behaviours, which can generalise to other long-term
conditions
Managing the Complexities of the Screen Industries: A Process Management Framework
Get PDFThe Screen Industries are characterised by dynamic, multifaceted projects that present distinctive challenges in process management, diverging significantly from structured sectors such as manufacturing or software development. Unlike industries that follow linear progressions with strict timelines and predefined outputs, creative content production is inherently fluid, iterative, and unpredictable. Conventional process management frameworks often fail to accommodate these complexities, leading to inefficiencies that hinder operational effectiveness (OE) and competitive advantage (CA). This research examines the challenges of process management within the Screen Industries, refining theoretical understanding and proposing a structured framework aligned with their distinct operational landscape.
By defining the Screen Industries and their five core sectors—film, television, commercials, documentaries, and video games—this study provides a clear classification, addressing longstanding ambiguities in academic and industry discourse. It critically examines how value is created and sustained across production phases, revealing that workflow stability, leadership alignment, and creative autonomy are as integral to success as financial returns. The study highlights the multidimensional nature of value and demonstrates that structured processes play a crucial role in balancing innovation and commercial viability. Sector-specific dynamics influence how value is perceived and managed, with different sectors prioritising distinct measures of success, such as audience engagement, interactivity, and brand impact. These variations underscore the need for process management systems that balance creative autonomy with structured workflows to mitigate risks.
Employing a mixed-methods research design, the study integrates quantitative and qualitative analyses to develop a comprehensive understanding of process management within the Screen Industries. The SERPENT Process Management Framework, structured around Leadership, Process, and Value, fosters creative flow, autonomy, and structured oversight. By enhancing process structures, milestone checkpoints, and operational transparency, it provides a tailored framework that strengthens OE and CA in an industry where adaptability, efficiency, and innovation are crucial to sustained success
Design & Analysis of Constrained Control for Power Inverters
No full textIn recent years, the rapid growth of deploying distributed energy resources (DERs) within the primary electrical grid and their widespread adoption in microgrid applications have significantly transformed the landscape of modern power systems. The increasing penetration of DERs, including photovoltaic systems, wind turbines, and energy storage units, necessitates the development of advanced control strategies for the power electronic converters that interface these resources with the grid. This shift is particularly critical as traditional control methods, designed for centralised generation, are no longer sufficient to address the dynamic and decentralised nature of DER-based systems. Inverters, one of the primary interfacing devices for controlling DERs, play a critical role in maintaining the stability and performance of modern power systems. The thesis aims to design and analyse novel control strategies for inverters, ensuring effective regulation of key parameters, including power, frequency, voltage, and current. The proposed control approaches aim not only to regulate these quantities, but also to keep them within prescribed operational limits to enhance the safety and reliability of the controlled system.
In particular, one of the primary contributions of this thesis is the development of state-limiting control strategies for all three main classifications of inverters in AC microgrids, as well as for inverters functioning as interlinking converters in hybrid AC/DC microgrid architectures. Initially, a novel control scheme is introduced for three-phase grid-following inverters, ensuring precise output power regulation while inherently constraining the magnitude of the inverter current. Subsequently, a dedicated current-limiting controller is proposed for interlinking converters, enabling power balance between interconnected AC and DC subgrids. Additionally, a new control method has been developed for grid-forming inverters in isolated microgrids, which can limit both frequency and current, even under transient conditions. An equivalent grid-supporting variant of this control approach has also been formulated for applications requiring grid connectivity. The last contribution lies in the systematic design of an optimal resonant control strategy for single-phase grid-connected inverters, which reduces current overshoots during grid voltage phase jumps. Finally, the theoretical validation of system stability under the proposed control frameworks is provided, demonstrating robust performance across a broad spectrum of dynamic operating conditions. The effectiveness of the developed controllers is further verified through detailed simulations and hardware-in-the-loop testing to assess the stability and performance of modern power systems
Prevalence and Associated Predictors and Determinants of Disordered Eating Behaviours (DEBs) Among Female Adolescents in Saudi Arabia
Get PDFBackground
Adolescence is associated with increased vulnerability to diet-related problems. Disordered eating behaviours (DEBs), in particular, are concerned with body image and weight dissatisfaction and can influence intake and growth. Literature on DEBs is scarce in Arab populations, especially in Saudi Arabia. The overall aim of this thesis was to assess the prevalence of DEBs in Saudi adolescents and to explore determinants contributing to these behaviours.
Methods
A systematic review assessing the evidence on the prevalence of DEBs in Saudi Arabia was followed by a sequential mixed-methods study comprising a quantitative survey and qualitative interviews. A survey of 416 female students aged 12–19 years in four Riyadh schools used the EAT-26 questionnaire to explore DEBs prevalence. In-depth interviews with 18 adolescents classified as high-risk of DEBs investigated the main determinants causing DEBs.
Results
The review found that DEBs rates nationwide ranged from 10.2% to 65.5%, with the eastern region having the highest prevalence. Older students had a higher prevalence than younger students, and males reported more DEBs than females. EAT-26 scores indicated that 29.6% of students reported a high-risk of DEBs. Age was a significant predictor of DEBs risk, with the older age group (16–19 years) reporting higher risk than the younger age group (12–15 years) (P=0.017). Interviews concluded that negative cognitions, conscious imitation/copying behaviours, bullying, comparisons, and negative comments were common determinants of DEBs. Some participants indicated that biological and familial variables may increase the risk of DEBs.
Conclusion
This thesis represents the first research exploring the prevalence and primary determinants of DEBs in Saudi female adolescents in Riyadh. The relatively high risk in this age group, and the importance of peers and family members as well as cognition, suggests that interventions to reduce risk need to address both individual factors and social pressures
Investigation of Candida albicans Suppression of Neutrophil Reactive Nitrogen Species in Zebrafish Larvae
Get PDFThough often a harmless commensal, C. albicans causes frequent mucosal infections and can cause life-threatening, invasive infections, especially in immunocompromised individuals. Greater understanding of C. albicans pathogenesis in vivo is required. I investigated C. albicans interactions with neutrophils, using zebrafish in vivo models, aiming to unravel mechanisms of C. albicans pathogenesis and host-pathogen interactions.
Reactive nitrogen species (RNS) are a critical host antimicrobial to kill C. albicans. I showed C. albicans suppresses neutrophil RNS levels in zebrafish. Heat-killed C. albicans caused an intermediate degree of RNS suppression, implying a passive mechanism for RNS suppression. Live C. albicans suppressed neutrophil RNS proximal to the site of infection, and also distally. My data support prior observations of C. albicans suppression of mammalian macrophage RNS in vitro.
I investigated mechanisms underlying neutrophil RNS suppression by C. albicans in vivo. C. albicans hyphae and arginase (car1) were revealed to have a role in RNS suppression.
Neutrophil RNS suppression was observed across a selection of C. albicans and non-albicans Candida spp. clinical isolates. RNS suppression by Candida spp. correlated with virulence in zebrafish in vivo, suggesting RNS suppression is important for Candida spp. pathogenesis in human disease.
Hif-1α is a potential host directed therapy (HDT) target, known to increase neutrophil RNS production in bacterial infection. However, the role of Hif-1α is poorly characterised in C. albicans infections. Hif-1α stabilisation protected against C. albicans infection in zebrafish in vivo, via a neutrophil-mediated, RNS-dependent mechanism, rescuing neutrophil RNS levels after C. albicans infection. Combination of Hif-1α with antifungals had an additive effect on zebrafish survival and clearance of C. albicans infection. Hence, Hif-1α is a potential target for a HDT for C. albicans infections.
This thesis demonstrated C. albicans suppression of neutrophil RNS in vivo, a potentially important strategy in Candida pathogenesis, and highlighted the potential of targeting if-1α and RNS in HDTs against C. albicans infections
Production of urban AI and robotics: Imaginaries and realities for AI experimentation in Shanghai
No full textThis doctoral thesis examines the contested production of urban artificial intelligence and robotics (UAIRs) as a co-constitutive process shaped by multi-scalar power negotiations among municipal interest group coalitions, transnational capital, geopolitical forces, and China’s central party-state. Through an in-depth qualitative case study of Shanghai’s UAIR practices, this research reveals how cities – particularly those of political-economic significance – are increasingly functioning as strategic frontiers for AI territorialisation, a phenomenon inadequately theorised in existing urban scholarship.
The study advances a relational, contextualised political economy framework to analyse two interlinked dynamics mediated through local structurally-oriented strategic actors: (1) how local coalitions perform technological sovereignty through demonstrative UAIR projects while accommodating global capital flows, and (2) how they reconcile national AI strategies with locally adapted implementation within multi-layered entrustment governance structures. Empirical analysis uncovers significant discrepancies between Shanghai’s AI policy imaginaries and their material outcomes, reflecting the constitutive tensions arising from multi-scalar power negotiations beyond urban boundaries. The findings yield three key conclusions:
1. UAIRs as multi-scalar co-production: UAIR production transcends urban and national territorial boundaries, being co-produced through the strategic navigation of competing political-economic regimes and diverse stakeholder interests.
2. UAIRs as a vision-material disjuncture: The significant gap between Shanghai’s AI imaginaries and their materialisation should not be ascribed merely to planning or implementation failures. Instead, it stems from a techno-utilitarian governance model operating through a multi-layered entrustment structure, which prioritises political legibility, geopolitical competition, and commercial opportunism over genuine urban needs.
3. Shanghai as an epitome of the re-territorialising strategic AI frontier: The Shanghai case epitomises the emergence of a new urban form wherein state strategic rescaling reconstitutes urban governance, thereby positioning the city as a strategic frontier in response to escalating geopolitical competition.
The thesis makes three primary contributions. Empirically, it provides one of the first systematic analyses of UAIR production within China’s urban political economy, offering crucial insights into a globally significant yet under-theorised context. Methodologically, the strategic relational framework developed in this thesis addresses the ahistorical and de-contextualised limitations in literature, capturing the co-constitutive interplay of discourse, materiality, and multi-scalar power within UAIR assemblage. Theoretically, this thesis pioneers a paradigm shift by reconceptualising the ‘experimental AI city’ as a performative enclave, and retheorising the ‘global AI city’ as a re-territorialising strategic frontier in the post-neoliberal geopolitical economy of AI.
By foregrounding the dynamics of strategic agency and structurally selective contexts, this research demonstrates the inadequacy of existing urban (global) AI frameworks in accounting for geopolitically contested AI urbanism. This study calls for relational, contextually grounded approaches to unpack the co-production of technology, multi-scalar power, and urban space. The thesis thus offers a critical conceptual toolkit for understanding urban technological transformation in a rapidly evolving global political-economic order
Advanced thermal management of stator-mounted PM machines
No full textThis thesis investigates the electromagnetic performance and thermal behaviour of stator-mounted permanent magnet (PM) machines, with a focus on various cooling methods.The electromagnetic performances of five stator-mounted PM machines are evaluated using Pareto fronts obtained through a multi-objective genetic algorithm, exploring the relationships among maximum torque, copper loss, and PM volume. The thermal performance of three representative stator-mounted PM machines, along with a surface-mounted PM machine, is analysed under both natural cooling and water-jacket cooling at different rotor speeds. For active cooling methods, forced air cooling and forced liquid cooling are applied to a modular FSPM machine. In the forced air cooling study, the effects of inlet conditions, flux gap width, and rotor speed are examined. For forced liquid cooling, three modified liquid cooling techniques are proposed. Furthermore, two coolants are tested in semi-flood cooling, and a series of simulations under different flux gap widths are conducted to assess their effectiveness
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