Saudi Cultural Missions Theses & Dissertations
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Item Restricted The Effects of Oil Price Variations on Stock Market Returns: Evidence from Saudi Arabia and Spain(Birkbeck, University of London, 2024-10) Alzamel, Hussah Adnan; Beckert, WalterThis study investigates the effects of oil price variations on stock market performance in Saudi Arabia and Spain. Specifically, we employ the autoregressive distributed lag model to estimate the effects of oil price changes on stock market returns in these net oil-exporting and oil- importing nations, respectively. The empirical findings suggest that, in both cases, oil price increases led to corresponding increases in stock market returns. However, the stock markets of both countries reacted differently to oil price changes during the COVID-19 pandemic, which caused a massive slump in global demand. In Saudi Arabia, a nation whose economy relied heavily on oil, the impact was negative, whereas in Spain, the impact was positive. Using the generalised autoregressive conditional heteroskedasticity (1,1) model, we also modelled volatility in the stock returns and found that oil price increase reduced volatility in the stock returns. Keywords: Saudi Arabia, Spain, ARDL, GARCH, oil prices, stock returns11 0Item Restricted Applications of Parameter Inference and Modelling in Cardiac Single-Cell Action Potential Models(University of Glasgow, 2024-09) Aldawoud, Antesar; Simitev, Radostin; Gao, HaoCardiac electrophysiological modelling has long been a valuable tool for exploring both normal and abnormal heart rhythms, playing a crucial role in diagnosing heart conditions and developing effective therapies. This thesis focuses on single-cell cardiac electrophysiology, with particular attention to the variability in action potential (AP) and its impact on antiarrhythmic treatments. The primary goal is to investigate this common issue in cardiac electrical excitation models and understand its implications for antiarrhythmic therapies. To achieve this, a variety of action potential models, ranging from complex to simplified, are employed to provide an analysis. Firstly, a method is presented that uses an asymptotic approximation of action potential duration (APD) in a simplified model to study ion-channel block dynamics. This approach involves determining the specific properties of each myocyte based on the parameter values of a selected model. Drug effects on ion conductance are quantified using a multiplicative factor, and a mathematical formula is developed to approximate APD. This formula is then used to establish model parameters as functions of APD and drug-induced changes in APD for each heart cell. Additionally, two protocol-related parameters are calibrated using an adaptive-domain approach based on optimal excitability. This precise formulation allows for direct assessment of the conditions required to maintain a constant APD or its variations. It also enables predictions about the proportion of excitable cells after drug application, as well as insights into stimulus periods and dose-response relationships, consistent with experimental data. Subsequently, a regression method is developed to predict drug responses in cardiac electrophysiology models by assessing how alterations in ion channel conductances affect model outputs. The method focuses on predicting changes in action potential duration (APD) following drug administration. The Ordinary Least Squares regression model provided accurate predictions, effectively capturing the relationship between drug-induced changes in ion channel conductances and APD. In addition to the standard regression model, an advanced approach is employed by incorporating nonlinear terms to capture the complex relationships between conductances and physiological biomarkers. These nonlinear predictors enable the model to account for interactions and dependencies that linear models often overlook. The enhanced model enables more accurate predictions of the effects of ionic conductances. Finally, a method is introduced to reproduce action potential variability observed in experimental rabbit cardiomyocytes using Gaussian process emulators and rejection sampling. The method accurately captures variations in APD and correlates them with changes in ionic conductances across a population of models. By utilizing rejection sampling in combination with GP emulation, large populations of models are efficiently generated, enabling the study of the interactions between ionic conductances, action potentials, and drug effects without requiring extensive computational resources. This thesis enhances the understanding of cardiac electrophysiology by addressing variability in action potential and its implications for antiarrhythmic treatments. It proposes an integrated approach combining modelling and experimentation, offering new insights into the complex dynamics of cardiac function.4 0Item Restricted Understating the mechanism of IL-33 release in keratinocytes in Atopic dermatitis (AD) in response to Sbi(University of Manchester, 2024) Babatin, Fatimah; Pennock, JoanneBackground: Atopic dermatitis (AD) is a chronic inflammatory skin disease characterised by epidermal barrier dysregulation and type 2 immune response. Staphylococcus aureus (S. aureus) colonises AD skin and induces the release of IL-33. Our study aims to investigate the mechanism of IL-33 release in keratinocytes in response to S. aureus second immunoglobulin (Sbi). Methods: The study investigated the release of IL-33 from normal human epidermal keratinocytes (NHEK) when exposed to second immunoglobulin staphylococcus (Sbi) and assessed it using ELISA. Protein tyrosine Kinase assay and Bioinformatics tools identified immunoglobulin (Ig) containing receptor candidates. The interaction between Sbi and inhibitors in NHEK was also measured through IL-33 ELISA. Additionally, the impact of Ig- containing domain receptor ligands was investigated using a cytokine array. Results: Sbi induced IL-33 release by NHEK after 15 minutes, confirming that Sbi triggers Th2 responses in the skin. Our potential Ig containing receptor candidates are FGFR, PDGFR, and VEGFR. However, our finding indicates that Sbi does not interact with these Ig containing receptors. Additionally, Sbi showed no impact on the production of RTK Ig containing domain receptor ligands in keratinocytes. The Growth factor ligands for the RTK receptors were found in the NHEK supernatant but were not significantly upregulated with Sbi. However, the RTK receptor expression was significantly upregulated when stimulated with Sbi, but the inhibitors did not prevent IL-33 release. The growth factor ligands for the RTK receptors were found. Conclusion: Our study found that Sbi actively stimulates the release of IL-33 from living cells after only 15 minutes. These results strongly suggest that Sbi is a potent stimulator for triggering Th2 responses in the skin. In contrast, the Ig domain-containing receptors (FGFR, VEGFR, PDGFR) appear not to bind with Sbi. Further work is needed to understand the signaling pathway by which Sbi induces the IL-33 release from keratinocytes, which may lead to the development of novel therapy for AD.8 0Item Restricted Role of Penicillin-Binding Proteins in Synthesis and modification of Bacillus subtilis cell envelope(Newcastle University, 2024) Alanazi, Yousef; Daniel, RichardThe peptidoglycan (PG) layer plays a crucial role in preserving the shape of bacterial cells and facilitating cell division in nearly all Gram-positive bacteria. Composed of glycan chains linked by short peptide fragments, PG creates a mesh-like structure that envelops the cytoplasmic membrane. During cell growth and division, membrane-bound PG synthases, known as penicillin-binding proteins (PBPs). PBPs are essential for building the bacterial cell wall, maintaining cell shape, and supporting bacterial replication. Bacteria exhibit a wide variety of PBPs, suggesting that despite their apparent functional redundancy, there are distinct roles within the PBP family. These seemingly redundant proteins can be vital for helping organisms adapt to and survive environmental stressors. Although the glycosyltransferases PBPs (class A PBPs) have been deleted, the minimal set of PBPs that are required for Bacillus subtilis survival and growth is not yet identified. Additionally, although the transpeptidases PBP2a and PBPH are well identified redundant partners, the way they are regulated and the influence on each other is still elusive. Finally, PBPX is known as penicillin binding protein with endopeptidase activity however its precious function is still not clear specially because it has been linked to Dlt proteins in response to cationic antimicrobial peptides (CAMPs). Here we have systematically deleted PBPs in B. subtilis until we identify strain with minimal PBPs which are PBP2B and PBP2a. The strain was capable of surviving and growing during exponential phase, but the growth was slower compared to the wild type. The strain with minimal sets of PBPs shows elongated shape under microscopy with less rigid cell envelope and changed in peptidoglycan composition but maintain the degree of cross linkage of PG compared to the wild type. We also showed that the deletion of pbpH increases the activity and quantity of PBP2a which was due to the transcriptional regulation between the redundant partners. The PBPH transmembrane domine play a role in the regulation of the redundant partner activity and quantity. Finally, this study shows that the PBPX play a role in modulating the cell surface charge and therefore decrease the sensitivity toward the CAMPs and the deletion of pbpX significantly decreases the d-alanine associated with the wall teichoic acid. The results tighter indicated that the PBPX is the protein that transfer the d-alanine from lipoteichoic acid to the wall teichoic acid.5 0Item Restricted Exploring the Role of Strategic Management Accounting in Enhancing Organizational Performance: A Comprehensive Literature Review(Swansea University, 2024-09) Alfaddah, Zuhair; Ojra, JafarThis dissertation explores the role of Strategic Management Accounting (SMA) in enhancing organizational performance through a comprehensive review of existing literature. SMA, which integrates financial and non-financial information with long-term strategic goals, is positioned as a critical tool for improving decision-making and maintaining competitive advantage. Key techniques such as Activity-Based Costing (ABC), the Balanced Scorecard (BSC), Target Costing, and Benchmarking are examined for their contributions to aligning management accounting with broader business strategies. The study identifies SMA’s potential to improve resource allocation, cost control, and performance measurement by linking accounting practices with strategic objectives. However, the successful implementation of SMA is challenged by factors such as complexity, high implementation costs, and resistance to cultural change within organizations. These barriers, especially prevalent in small and medium-sized enterprises (SMEs), underscore the importance of tailoring SMA techniques to specific organizational needs and fostering cross-functional collaboration. The dissertation also highlights gaps in the literature, particularly the under-exploration of SMA in service industries and its integration with emerging business trends such as sustainability and digital transformation. Recommendations are provided for practitioners on how to overcome implementation barriers, invest in data infrastructure, and integrate SMA into strategic planning processes. In conclusion, while SMA offers significant benefits for improving long-term competitiveness and decision-making, its effectiveness depends on the organization's ability to align SMA practices with strategic goals, adapt to evolving market conditions, and overcome operational and cultural challenges. The study suggests areas for further research, including the application of SMA in non- manufacturing industries and its role in supporting sustainability initiatives5 0Item Restricted EXPLORING THE ATTITUDES AND MOTIVATION OF SAUDI STUDENTS TOWARD LEARNING ENGLISH: A GENDER-BASED STUDY(University of Nottingham, 2024-05-09) Hadhram, Yousef; Fuentes, Valeria RiverosThis study explores the motivations and attitudes of Saudi students towards learning English as a second language (L2) using a mixed-methods approach. The research involved 264 participants, comprising 177 males and 86 females, and employed both quantitative surveys and qualitative written interviews to provide a comprehensive analysis. The findings reveal that Saudi students generally exhibit positive attitudes towards learning English, with no significant gender differences. While quantitative data indicate that students are predominantly intrinsically motivated, qualitative analysis suggests a more nuanced picture, with both intrinsic and extrinsic motivations playing significant roles. These results challenge the prevailing literature, which often emphasizes extrinsic motivation as the primary driver in L2 learning. The study highlights the complexities of motivational dynamics and suggests the need for further research to explore the influence of factors such as academic discipline, age, and proficiency levels. Limitations include the small sample size, gender imbalance, and potential language barriers affecting survey comprehension. Future recommendations include expanding the sample size, ensuring gender balance, and translating research instruments into the participants' native languages to enhance data quality.2 0Item Restricted Optimisation of Respiratory Syncytial Virus (RSV) whole genome sequencing of subtypes A and B(University of Nottingham, 2024-07) Alamoudi, Nouran Abubaker; King, Barnabas; Mcclure, PatrickRespiratory Syncytial Virus (RSV) is a major cause of lower respiratory tract infections, causing significant morbidity and mortality rates worldwide. RSV mainly affects infants, children under five years old, and older or immunocompromised adults. Establishing a cohesive method for the detection and identification of RSV could significantly improve monitoring and surveillance of RSV cases globally. The present study focused on optimising previously developed 400 base pair tiled-amplicon schemes for the whole genome sequencing of RSV subtypes A and B. We have developed novel ~1200 base pair primer schemes to increase sensitivity and produce a cost-efficient method for RSV genome sequencing. Samples were chosen between 2014 to 2024 and sequenced using Oxford Nanopore Technology’s PromethION device to acquire high- throughput genome data of both RSV subtypes. Our results revealed high potential for the optimised RSV A scheme, with all but two amplicons achieving genomic coverage depth of > 1000 reads per amplicon. However, the developed RSV B schemes generated insufficient results for most of RSV B samples. Moreover, the samples tested for RSV A displayed greater strain variability after phylogenetic analysis. In contrast, RSV B samples were of closely related strains and showed less genomic diversity. Acquiring high-throughput genomic data for RSV can hugely influence our understanding of the diversity of RSV, in addition to its evolutionary and seasonality patterns, which subsequently assists in the management of this virus on a global range. Furthermore, constituting a unified method for RSV sequencing largely impacts the implementation of successful surveillance systems for RSV infections.3 0Item Restricted Future Glass Factory: Precision Shaping of Glass using Amorphous Silica Nanocomposite Prepolymer and Replication Molding(Queen's University Belfast, 2024-05-15) Atwa, Yahya; Shakeel, Hamza; McNeill, DavidGlass, a versatile and indispensable material, plays a crucial role in industries such as electronics, optics, and chemical sensing due to its exceptional transparency, thermal stability, and recyclability. Despite the benefits of traditional glass fabrication methods like glass blowing, these approaches face significant challenges, including energy-intensive processes, susceptibility to defects, and limitations in creating complex geometries. To address these issues, this thesis introduces a novel fabrication method that combines printable amorphous silica nanocomposite suspensions with replication molding. This innovative technique offers enhanced design flexibility, reduced material waste, and cost-effective production, enabling the creation of intricate 2D and 3D geometries with improved structural and surface quality. The research explores this method’s applications in chemical sensing and resonant devices, highlighting its transformative potential for advanced glass manufacturing. The proposed method employs polydimethylsiloxane (PDMS) molds as templates. A glass prepolymer is dispensed into these molds, cured using ultraviolet light, and then subjected to thermal debinding and sintering processes. These steps transform the prepolymer into fully fused silica, achieving uniform thickness, minimized shrinkage, and smooth surfaces. To validate the method, extensive characterization techniques, including surface roughness measurements, thermal analysis, and computational modeling, were employed to ensure high-quality outcomes. Optimization strategies further enhanced device performance by addressing challenges such as bending during processing and improving sintering results. This thesis demonstrates the efficacy of this approach through key applications. For chemical sensing, a transparent 3D-printed fused silica gas chamber was integrated with a graphene-based sensor for detecting volatile organic compounds (VOCs). The chamber's transparency enabled ultraviolet-assisted regeneration of graphene’s adsorption properties, restoring sensitivity and ensuring long-term stability. Additionally, a micro dielectric barrier discharge photoionization detector (μDBD-PID) was developed using this technique. This detector employed a colorimetric readout mechanism to analyze changes in plasma luminescence during VOC detection, achieving high sensitivity and selectivity for both polar and non-polar compounds. These advancements highlight the method’s capacity to produce robust and high-performance chemical sensing devices. In the field of resonant devices, the fabrication process was used to create planar double paddle oscillators (DPOs) with varying thicknesses (0.5 mm, 0.8 mm, and 1 mm). These devices exhibited excellent resonance characteristics, with the 1 mm thick DPO achieving a quality factor (Q-factor) of 1,261 in the CL1 mode and 4,563 in ring-down measurements. Similarly, 3D hemispherical resonators (HSRs) were fabricated, with significant improvements in surface smoothness, reducing roughness to 103 nm in second-generation devices. Experimental and computational analyses identified resonance modes (N = 2, N = 3, N = 4), with the highest Q-factor of 482k observed in the N = 3 mode. These results highlight the method's ability to produce high-performance resonant structures essential for sensitive detection and precision applications. In conclusion, this thesis presents a transformative approach to glass fabrication that combines innovative techniques and meticulous optimization to overcome the limitations of traditional methods. By demonstrating its applicability in chemical sensing and resonant device manufacturing, the research underscores the potential of printable glass technologies to revolutionize precision manufacturing. The findings significantly contribute to advancing the state of the art in microfabrication, paving the way for innovative solutions across academia and industry. This work highlights the integration of sustainability, efficiency, and advanced functionality in modern glass-manufacturing processes.14 0Item Restricted Perceptions of Adults who stutter after attending stuttering support groups in Saudi Arabia(University of Sheffield, 2024-08) Alrasheed, Rahaf; Cunningham, StuartBackground: Stuttering, marked by disruptions in speech flow, often leads to significant psychological and social challenges (Boyle, 2013a). Support groups have been identified as a beneficial approach to enhancing both speech fluency and psychosocial well-being among people who stutter (Gerlach et al., 2019). Aim: To investigate the impact of participation in stuttering support groups on perceptions of speech fluency and psychosocial well-being of adults who stutter in Saudi Arabia. Method: A total of 18 adults who stutter were recruited to this study via SSGs leaders. The study used a survey to collect data and employed a mixed methods approach by integrating both quantitative analyses using the Statistical Package for Social Sciences (SPSS) and qualitative thematic analysis to explore participants' experiences and perceptions. Results: The findings revealed that support groups largely enhance self-acceptance and confidence while showing variable improvement in speech fluency among participants. Conclusion: This research contributes valuable insights into the role of support groups in the lives of adults who stutter, advocating for their continued development and accessibility in Saudi Arabia.4 0Item Restricted A Qualitative Exploration of School Distress in Primary School-Aged Children: The Voice of the Parent(University College London, 2024-08-20) Madani, Jude; Hillman, SaulIn response to the gap in qualitative research looking into early experiences of School Distress, and the need for this research to inform early intervention, this study elicited parents’ views on factors contributing to SD in their primary school-aged children. An inductive thematic analysis drew upon data from 4 semi-structured interviews with mothers of primary school girls with SD. Data analysis revealed themes surrounding school-based determinants of distress (i.e., unexpected change in school, overwhelming sensory environments, challenging peer interactions) and the contributing role of neurodiversity and unmet needs in diverse manifestations of distress. Other themes highlighted the emotional impact of managing SD for parents, and sources of support for SD that constituted increasing inclusivity in school and improving home-school cooperation. These findings highlight the heterogeneity in SD presentations and the need for adjustments in mainstream settings to better meet children’s needs. Future research is needed to understand the experiences of primary school-aged boys and develop sensitive detection models for SD for children whose distress responses are less obvious.5 0