Saudi Cultural Missions Theses & Dissertations
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Item Restricted Investigation of Novel Type III Secretion System Protein Effectors of Aeromonas veronii(Saudi Digital Library, 2025) Alfaify, Abdulkhaleg; Shaw, JonathanThe type III secretion system (T3SS) plays a crucial role in the pathogenesis of various Gram-negative bacteria, enabling them to directly inject effector proteins into host cells. This study focuses on the identification, characterization, and functional analysis of putative T3SS effector proteins (AopX, PteB, and PteA) in Aeromonas veronii. Insertional gene mutants were generated and evaluated using the Galleria mellonella larvae infection model, showing significant alterations in virulence phenotypes. Transcriptomic analysis of an exsD mutant strain provided insights into the regulation of these novel effectors and demonstrated that they were part of theT3SS regulon. The study further characterized these proteins through expressing them in both Saccharomyces cerevisiae and A549 mammalian cells. Fluorescence imaging analysis showed that these proteins had significant impacts on host cell morphology and cytoskeletal organization. Additionally, BioID proximity labelling combined with mass spectrometry proteomics analysis identified host protein interactions and key cellular pathways that influenced by these bacterial effectors. Furthermore, protein purification was optimized using various chromatography approaches and computational modelling via AlphaFold and Phyre2 was used to predict and align protein structures. Overall we found that AopX, PteB, and PteA are regulated by the T3SS regulon. AopX primarily disrupts the actin cytoskeleton in both yeast and A549 cells, most probably through interacting with Filamin A, while PteB prevents bud formation and affects cell cycle progression by interacting with Serine/Threonine phosphatases. This comprehensive investigation enhances our understanding of T3SS effector proteins in A. veronii pathogenesis and provides insights into their regulation, structural features, and specific mechanisms of host cell manipulation.10 0Item Restricted Design and Analysis of Next Generation Wireless Networks(Saudi Digital Library, 2025) Altuwairgi, Khaled Humaid; Hamdi, KhairiRecent advancements in wireless communications have increased the demand for high data rates, massive connectivity, high spectral and energy efficiency, and low latency, which cannot be met by existing systems. The sixth-generation (6G) wireless network is envisioned as the next step to support these demands by integrating technologies, including intelligent reflecting surface (IRS), backscatter communication, non-orthogonal multiple access (NOMA), integrated sensing and communication (ISAC), and terahertz (THz) communications. Specifically, the IRS enhances the energy and cost efficiency by controlling the propagation environment through an array of reflecting elements. Backscatter communication enables passive battery-free devices to communicate using external RF signals, offering an energy-efficient and low-cost solution for the Internet of Things (IoT) paradigm. NOMA improves spectral efficiency and massive connectivity by allowing multiple users to share the same time-frequency resources, while ISAC combines sensing and communication functionalities into a single system for efficient spectrum and hardware usage. Finally, THz communication addresses the current limited spectrum by providing extensive bandwidth that supports ultra-high data rates. This thesis studies the integration of these technologies with a special focus on IRS and backscatter communications, considering various system models and realistic scenarios. It evaluates the performance of IRS-aided backscatter communication in both dedicated and ambient configurations using different detection techniques and transmission schemes. It also investigates IRS-assisted THz to serve multiple users through NOMA and wireless powered communication under various practical scenarios. Moreover, it explores the integration of ISAC with ambient backscatter communication. The thesis identifies the potential benefits of these technologies and examines the adverse impacts of practical factors such as beam misalignment, co-channel interference, imperfect successive interference cancellation, phase shift quantization errors, and hardware imperfection. Accurate analytical expressions are developed for key metrics, including bit error rate, ergodic capacity, and outage probability, under various system models and transmission schemes. Numerical and simulation results are provided to validate the accuracy of the theoretical analysis and provide valuable insights into the system design.9 0Item Restricted Sustainable Waste Management of Date Palm Fronds in Saudi Arabia: Pyrolysis-Derived Biochar Integration into Construction Materials for Carbon Sequestration(Saudi Digital Library, 2024-09) Shaiban, Saad; Scott, BanksThis study focuses on integrating biochar derived from date palm fronds into cement production in Riyadh, Saudi Arabia (KSA), to optimise carbon sequestration (CCS) and reduce carbon emissions. Employing a mixed-method approach, the research combines quantitative Life Cycle Assessment (LCA) using SimaPro software with qualitative sustainability analysis through the Bioeconomy Sustainability Indicator Model (BSIM) and Sustainable Development Goals (SDGs) indicators. Phase 1 compares the environmental impact of traditional open combustion versus pyrolysis for biochar production, revealing that pyrolysis significantly reduces carbon emissions from 3.5 tons CO₂-equivalent per ton of waste to 646 kg CO₂-equivalent. This substantial reduction supports Riyadh's climate goals and aligns with KSA’s Vision 2030 sustainability objectives. Phase 2 evaluates the integration of biochar into cement mortar, showing that a 20% substitution of cement with biochar reduces emissions by 24.81 kg CO₂-equivalent per ton of mortar, potentially saving up to 1,796 million tons of CO₂-equivalent annually based on current cement production levels. The sustainability analysis using BSIM highlights benefits such as job creation and economic growth while identifying transportation logistics risks and production efficiency risks. Additionally, the study assesses contributions to SDGs, particularly in climate action, sustainable cities, and responsible consumption and production. The study recommends optimising the supply chain, investing in advanced pyrolysis technology, and supporting market development through policy incentives. Future research should focus on the long-term performance of biochar, explore additional applications in agriculture and water treatment, and further integrate biochar into sustainable construction practices. This research provides valuable insights for advancing sustainable waste management and construction practices in Riyadh, contributing to climate action and supporting regional and global sustainability efforts.9 0Item Restricted Development of a home based resistance exercise programme for muscle strength and function during weight loss(Saudi Digital Library, 2025) Binmahfoz, Ahmad; Gray, StuartThesis abstract Background The prevalence of obesity continues to increase, representing a major public health concern across the globe. While dietary interventions can reduce body mass, the concurrent loss of fat free mass and muscle strength is a potentially deleterious consequence. Resistance exercise may help preserve muscle mass and function during weight loss, yet its implementation remains challenging. This thesis investigated the potential of home-based resistance exercise to attenuate these deleterious effects of weight loss through three research studies. Methods Study 1 included a systematic review and meta-analysis examining the effects of resistance exercise on body composition, muscle strength, and cardiometabolic health during dietary weight loss. Study 2 employed qualitative methods to explore experiences and perceptions of resistance exercise among people living with overweight or obesity (n=11), informing a theory of change for intervention development. Study 3 evaluated the effects of a 12-week home-based resistance exercise intervention, during dietary weight loss, through a randomised controlled pilot trial (n=48). Results The systematic review and meta-analysis (25 RCTs) demonstrated that supervised resistance exercise during dietary weight loss preserved fat free mass (SMD: 0.40, p<0.001), increased fat mass loss (SMD: -0.36, p<0.001), and improved muscle strength (SMD: 2.36, p<0.001) relative to a no exercise control. The qualitative study identified multiple barriers, including pandemic-related limits, access to facilities and financial constraints to traditional gym-based resistance exercise, and indicated strong preferences for home-based alternatives. The pilot trial showed that, during weight loss, home-based resistance training improved grip strength (p=0.046), knee extensor maximal voluntary contraction force (p=0.019) and sit-to-stand performance (p<0.001), but did not have any effects on body composition (body mass index, total body mass, fat mass, fat free mass, muscle thickness) compared to dietary weight loss alone. Conclusions The current thesis demonstrates that supervised resistance exercise enhances the benefits of diet induced weight loss by preserving muscle mass and improving muscle function. The development and evaluation of a home-based programme showed promising results for overcoming traditional barriers to resistance exercise participation and improving muscle strength and function, but not muscle mass. These findings support the implementation of accessible resistance exercise interventions during weight loss for people living with overweight or obesity.12 0Item Restricted Exploring expression of neurodevelopmental susceptibility genes in the foetal human thalamus and other related structures(Newcastle University, 2024) Alhesain, Maznah; Fiona, LeBeau; Gavin, ClowryThe thalamus is a brain region consisting of neuronal clusters and with a large number of connections which are responsible for several important functions including cognitive functions. It serves as a major relay centre, transmitting and modulating information between the cerebral cortex and subcortical structures. Given its involvement in higher-order cognitive functions, abnormalities in thalamic development have been implicated in various neurodevelopmental disorders, including schizophrenia and autism spectrum disorders. However, the developmental process of these nuclei in the human brain is still unknown. Understanding the developmental trajectory of the thalamus in humans is essential for several reasons. Firstly, while rodent models have provided insights into thalamic development, there are significant species-specific differences in the timing, organization, and molecular regulation of thalamic nuclei formation. These differences necessitate direct investigation of human developmental processes to bridge the gap between animal models and human neurodevelopment. Secondly, delineating how thalamic nuclei emerge during early foetal development may provide critical information on the origins of functional specialization within the thalamus, shedding light on how distinct neuronal populations are specified and how their connectivity is established. Finally, by identifying molecular markers and gene expression patterns specific to early thalamic development, we can gain a deeper understanding of the genetic and cellular mechanisms that may contribute to neurodevelopmental disorders, potentially informing future diagnostic and therapeutic approaches. This study aims to investigate gene expression patterns in the human thalamus, extending from 8 to 21 PCW, in order to track the development of each thalamic nucleus. Additionally, we focus on 14 PCW to identify distinct thalamic nuclei based on the expression of a unique combination of transcription factors and other genes/proteins. We also aim to investigate the expression of susceptibility genes linked to neurological diseases such as FEZ1, NRXN1 regarding their expression in specific thalamic nuclei. The methods we used are immunostaining and RNAscope in situ hybridisation, including double staining methods for multiple markers. Sections were taken from human early foetal brains (ethically sourced and supplied by the Human Developmental Biology Resource), in all planes and covering the extent of the diencephalon. Sections taken at 14 PCW were aligned with 3-D maps of the forebrain collected by structural MRI scanning. The expression of combinations of markers were localised to particular regions of the thalamus. We also analysed open source scRNAseq data with the aim of identifying clusters of cells grouped by shared gene expression patterns. We also investigated the expression of neurodevelopmental disease susceptibility genes in specific nuclei and cell types of the thalamus and telencephalon. This study provides significant insights into the early development of the human thalamus and telencephalon. The study highlights distinct gene expression patterns and the emergence of thalamic nuclei from a protomap. Our findings demonstrate that different transcription factors and molecular markers define specific thalamic regions, reinforcing the concept that a structured thalamic map begins to emerge by 14 PCW. Furthermore, we identified 15 distinct groups of cells with functional characteristics, supporting the notion that thalamic differentiation is an intricate and highly regulated process. It also implicates that neurogenesis and extensive cellular migration are critical processes during this crucial period. The differential expression of neurodevelopmental disease susceptibility genes in the thalamus further underscores the importance of studying early thalamic development in the context of neurological disorders. The high expression of FEZ1 in progenitor cells, transitioning to glutamatergic neurons, and the elevated presence of NRXN1 in the thalamus suggest potential roles in neuronal connectivity and function. These findings may provide critical clues for understanding the etiology of conditions such as schizophrenia, where thalamic dysfunction has been implicated. Overall, this study bridges a crucial gap in our knowledge of human thalamic development, and lay the foundation for future research into the molecular mechanisms underlying thalamic organization. Further investigations, including functional studies and longitudinal analyses, will be essential for uncovering how early developmental events shape thalamic function and its implications for neurodevelopmental and neuropsychiatric disorders.6 0Item Restricted VOCATION, EDUCATION, AND MARRIAGE IN NOVELS BY GEORGE ELIOT, CHARLOTTE BRONTË, AND ANNE BRONTË(Indiana University of Pennsylvania, 2025) Alazmi, Miad; Michael T. WilliamsonThis dissertation intends to pose a question that links an important nineteenth-century theory of education with literary works: how John Ruskin’s educational theories offer new insights into exploring the intellectual growth of Victorian women as shown in George Eliot's The Mill on the Floss (1860), Anne Brontë's Agnes Grey (1847), and Charlotte Brontë's Jane Eyre (1847), Shirley (1849), and Villette (1853). The study compares the novelists’ educational views with Ruskin’s theory and the ideologies that form its base to develop a counter-narrative to traditional feminist critiques of these texts. Drawing on Clare Carlisle’s analysis of vocation and marriage and Ruskin’s view on education, the study explores how the themes of vocation, education, and marriage intersect to shape each female protagonist’s journey toward a fulfilling intellectual life. While feminist critics such as Elaine Showalter, Sandra Gilbert, Susan Gubar, and Sally Shuttleworth have focused on gender constraints and patriarchal repression, this dissertation revisits the selected novels through the lens of vocation and education as intellectual and moral callings. Carlisle’s readings offer a more nuanced framework in which marriage and vocation are not only sites of conflict but also potential spaces for growth. Ruskin’s educational philosophy particularly in Sesame and Lilies and The Ethics of the Dust emphasizes a curriculum that develops both intellect and character, proposing an educational vision that, while gendered, urges moral and mental refinement for women. Through examining how the selected heroines capitalize on education to discover and pursue their vocations and redefine marriage as a site of mutual development, the study argues that these women novelists not only portray the limitations of their time but also envision education as a pathway toward intellectual agency. Thus, the dissertation highlights how Eliot, Anne Brontë, and Charlotte Brontë challenge traditional gender norms and participate in a broader philosophical discourse on women's intellectual lives during the Victorian period.6 0Item Restricted Investigation of Thin Al2O3 Films Grown by Atomic Layer Deposition (ALD) on TiO2 substrate(Flinders University, 2025) Alrashdi, Fahad Fraih Alzabni; Andersson, Gunther GAbstract Atomic layer deposition (ALD) is a feasible method for thin film deposition which allows the formation of a thin film of metal oxides on the various substrates. The film deposition is carried out in a vacuum reactor using chemical precursors (typically gases) which can react with the surface in a self-limiting manner. Each cycle in the ALD process can, in theory, form a monolayer of the desired metal oxide. Because the monolayer is deposited in each cycle, the thickness of the resulting film is related to the number of ALD cycles. In this thesis, the deposition of thin film Al2O¬3 on TiO2 nanoparticles by ALD was investigated. The main goal was to investigate whether Al2O¬3 can coat the inside of the pores of a porous TiO2 substrates or not. To obtain the answer, the chemical composition of the sample surface was studied using X-ray photoelectron spectroscopy (XPS). The initial X-ray photoelectron survey scan spectrum for each individual sample was recorded, followed by the high-resolution scans for the elements of interest. Moreover, the morphology of substrate after Al2O3 deposition by ALD was also examined using Scanning Electron Microscopy (SEM). In one experiment, four samples of Al2O3 on TiO2 substrate were prepared. Three of these samples were mixed, redissolved in ethanol, and redeposited on to a new silicon wafer. This was labelled as the redeposited sample. While the other one sample was labelled as the reference sample. The relative intensity of Al/Ti from all samples were calculated. It was found that Al2O3 intensity decreases. This result suggests that the diffusion of Al2O3 to porous structure of the substrate did occur.11 0Item Restricted Lightweight ML-Based Drone Intrusion Detection System Through Model Compression(University of North Texas, 2025) Alruwaili, Fawaz Juhayyim M; Cihan, TuncThe adoption of drones in diverse domains (e.g., surveillance, agriculture, and disaster management), together with their integration of advanced technologies and dependence on wireless communication, has significantly increased the need to secure drone networks against cyber threats. Traditional network-based intrusion detection systems (NIDS) can be insufficient against novel or adaptive cyber threats and exceed the computational limits of drones. Thus, we need lightweight and efficient drone-specific NIDS solutions. This dissertation addresses this concern with the goal of achieving an effective balance between security, efficiency, and model accuracy without significantly compromising detection performance. Hence, two complementary main contributions are proposed: First, a lightweight ML-based NIDS optimized for individual drones, utilizing a quantized deep neural network (DNN) through post-training quantization (PTQ), enabling real-time, on-board intrusion detection. Second, a framework for swarm-based deployments that leverage federated learning and knowledge distillation to enable distributed training and lightweight model deployment while preserving data privacy and minimizing communication overhead. Both contributions were evaluated using real-world drone network datasets. The first contribution achieved 95.03% accuracy with significantly reduced model size and inference latency, making it suit- able for real-time and onboard deployment. The second contribution was deployed using Raspberry Pi 4 devices and demonstrated improved accuracy, convergence, and communication efficiency, achieving up to 76% reduction in communication overhead and 29% lower CPU usage. The results demonstrate the practicality and effectiveness of the proposed solutions in meeting the unique demands of both individual and swarm-based drone deployments, while achieving a robust balance between security and efficiency.14 0Item Restricted Artificial Intelligence Law in Saudi Arabia(ST.Thomas Uinversity, 2025) Alharbi, Ibrahim; Wiessner, SiegfriedThis dissertation examines the legal and regulatory frameworks governing artificial intelligence in Saudi Arabia, analyzing the intersection of modern technological advancement with traditional Islamic principles and international standards. Through the lens of the New Haven approach, this research investigates how Saudi Arabia balances innovation with cultural values while developing comprehensive AI regulations. The study focuses particularly on the kingdom's efforts to establish effective legal mechanisms for AI governance while maintaining alignment with Sharia principles and meeting global technological standards. The research employs a comparative methodology, analyzing Saudi Arabia's regulatory approach alongside the United States' frameworks, identifying potential areas for enhancement while recognizing the unique cultural and legal context of the Kingdom. This analysis reveals significant developments in Saudi Arabia's AI regulatory landscape, particularly through initiatives such as Vision 2030 and the establishment of the Saudi Data and Artificial Intelligence Authority (SDAIA), while also identifying areas requiring further development. Key findings demonstrate that Saudi Arabia's approach to AI regulation reflects a sophisticated understanding of the need to balance technological advancement with ethical considerations and cultural preservation. The research identifies crucial areas for regulatory development, including the need for specialized legal frameworks addressing AI-specific challenges, enhanced institutional capacity for implementation, and mechanisms for ensuring compliance with both international standards and Islamic principles. The study makes several original contributions to the field. First, it provides a comprehensive analysis of Saudi Arabia's emerging AI regulatory framework from both legal and ethical perspectives. Second, it demonstrates how Islamic legal principles can effectively guide modern technological regulation. Third, it offers practical recommendations for developing regulatory frameworks that serve both technological advancement and social welfare. This research has significant implications for policymakers, legal practitioners, and technology developers in Saudi Arabia and beyond. It suggests the need for a carefully balanced approach that promotes innovation while protecting social values and individual 8 rights, potentially serving as a model for other nations seeking to harmonize technological advancement with cultural preservation.9 0Item Restricted Evaluation Of Surface Roughness And Marginal Microleakage Of Alkasite Material (Cention N) Versus Resin Modified Glass Ionomer In Class V Restoration In Primary Molars (In Vitro Study)(Cairo University, 2024) Althuwaini, Abdulrahman Suliman; Hamdy, Mahmoud; Mamdouh, NouranAim: The present study assesses the marginal microleakage of Alkasite material (Cention N) compared to resin-modified Glass Ionomer in restoring class V cavities in primary molars. Methodology: A total of 22 second primary molars were extracted, prepared for the Class V cavity, and subsequently divided into two groups (1 & 2), each containing 11 molars. The samples were restored using either material following the manufacturer's instructions. Marginal microleakage was assessed using the dye penetration assay using a scoring system (0-4), which was subsequently followed by microscopic examination with a stereomicroscope. The collected data were statistically analyzed and compared using the independent t-test at p<0.05 level of significance. Results: According to the findings, the occlusal and gingival margins of both restorative materials exhibited microleakage scoring levels between 1 and 4, with the Cention N group exhibiting higher microleakage scores at the occlusal margin. In comparison to Riva Light Cure, Cention N demonstrated marginal microleakage depths that were lower in both the occlusal and gingival margins. Conclusion: Both tested materials exhibited marginal microleakage, although Cention N was less than Riva Light Cure, suggesting the superiority of Cention N over Riva Light Cure in the sealing quality at the interface between the restoration and the tooth0 0