Saudi Cultural Missions Theses & Dissertations
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Item Restricted Plasma Reforming Technologies for Low Carbon Hydrogen Production(University College London (UCL), 2024-09) Alrasheed, Bader; Materazzi, MassimilianoThis project investigates the use of plasma-assisted methane pyrolysis for low-carbon hydrogen production and addresses the urgent global need for sustainable energy solutions. With hydrogen playing an important role in the transition to cleaner energy, the research focuses on developing a computational model using Ansys Chemkin-Pro to simulate the plasma pyrolysis process. The objective is to maximize hydrogen production while significantly reducing CO2 emissions, compared to traditional methods such as steam methane reforming. The study involves validating the model with experimental data and optimizing the process parameters for industrial-scale applications. Through a comparative analysis of different plasma conditions and feed compositions, the research identifies the most efficient scenarios for hydrogen production. The results show that plasma pyrolysis offers a feasible alternative for low carbon hydrogen production and allows for the utilization of carbon black as a valuable by-product. However, there are challenges that require further investigation to enhance the scalability and economic feasibility of this technology, such as optimizing reaction mechanisms and managing by-products. The study concludes with recommendations for future work, including reviewing kinetic data, exploring the option of an additional reactor, exploring the option of adding catalysts to the system, conducting laboratory experiments, and conducting detailed economic analysis to support the transition from research to industrial implementation.22 0Item Restricted The role of the International Court of Justice and international counsel as agents in the development of international law: A sociological perspective.(Kings College London, 2024-09-02) Alotaibi, Khalid Turki; Ridi, NiccolòWhereas the 19th century was characterized by the proliferation of international conventions and organisations such as the ICJ given increased State relations, legal positivism was prioritized over founding or viewing international law from a sociological perspective in light of an apparent urgency to establish international peace and security through the construction of international law and human rights frameworks. It is this relegation of the sociological perspective of international law that this research is concerned with as it seeks to interrogate form a sociological perspective, the role, scope and effect of ICJ decisions as well as the participation of international legal counsel in the development of international law. This is premised on the fact that judges of the ICJ through advisory opinions as well as international counsel, constitute an integral social entity through which the sum of its parts works to influence the development and/or creation of international law. The underlying objectives of this research include: an analysis of the statutory duty of the ICJ to interpret and apply international law within the confines of article 38 of the ICJ Statute; a critical analysis that focuses on the conduct of the ICJ to exceed the statutory parameters set by article 38 of the ICJ Statute by developing and creating international law; an analysis of scholarly perspectives on the development and creation of international law by the ICJ; and an analysis of scholarly perspectives on the role of international legal counsel in developing international law at the ICJ. In seeking to explore these objectives, this research identified that Judges of the ICJ, international counsel and agents fill a critical space within the structural-functional perspective of sociology which emphasises the collective role of social entities to achieve social order and social integration. This research concludes that a sociological appreciation of the role of ICJ and international counsel on the development of international law finds its place within a structural-functional perspective that prioritizes the role and effect brought about by the sum of individual social entities in a society as compared to viewing social entities in isolation.9 0Item Restricted Determinants of Traumatic Dental Injuries Among Adolescents in England A secondary analysis of the Children’s Dental Health Survey 2013(University College London, 2024-09) Asiri, Ali; Tsakos, Georgios; Blokland, AlexBackground: Adolescents are particularly vulnerable to traumatic dental injuries (TDI), which have a higher global prevalence in this age group. This study aimed to explore the associations between various demographic, clinical, behavioral, and socioeconomic risk factors with TDI among 12- and 15-year-old adolescents in England. Methods: This is a cross-sectional study and secondary data analysis of the Children’s Dental Health Survey 2013 (CDHS2013), using a nationally representative sample. A total of 2,126 adolescents were included after excluding cases with missing data (differences between the analytical sample and those with missing data were negligible). The analysis employed appropriate survey weights and examined demographic (age, sex, ethnicity), clinical (positive overjet, dental caries), behavioral (smoking, alcohol drinking), and socioeconomic factors (free school meals (FSM) eligibility , area deprivation, rural/urban classification) using multivariable logistic regression to model associations with TDI. Results: The overall prevalence of TDI in the sample was 10.98%. In the fully adjusted model, male adolescents were more likely to experience TDI compared to females (OR=0.64, 95% CI= 0.43-0.95). Adolescents who had never consumed alcohol had 37% lower odds of developing TDI (OR=0.63, 95% CI= 0.42-0.94). All other demographic and behavioral risk factors, as well as clinical and socioeconomic factors were not significantly associated with TDI. Conclusions: The study identified two key risk factors for TDI: being male and alcohol consumption. These findings highlight the importance of emphasizing on these risk factors while planning for preventive interventions and public health campaigns on TDI. Future research should adopt longitudinal designs to better assess the temporal relationship between these risk factors and TDI and include a broader range of variables for a more comprehensive understanding of TDI etiology.16 0Item Restricted Developing a Generative AI Model to Enhance Sentiment Analysis for the Saudi Dialect(Texas Tech University, 2024-12) Aftan, Sulaiman; Zhuang, YuSentiment Analysis (SA) is a fundamental task in Natural Language Processing (NLP) with broad applications across various real-world domains. While Arabic is a globally significant language with several well-developed NLP models for its standard form, achieving high performance in sentiment analysis for the Saudi Dialect (SD) remains challenging. A key factor contributing to this difficulty is inadequate SD datasets for training of NLP models. This study introduces a novel method for adapting a high-resource language model to a closely related but low-resource dialect by combining moderate effort in SD data collection with generative AI to address this problem of inadequacy in SD datasets. Then, AraBERT was fine-tuned using a combination of collected SD data and additional SD data generated by GPT. The results demonstrate a significant improvement in SD sentiment analysis performance compared to the AraBERT model, which is fine-tuned with only collected SD datasets. This approach highlights an efficient approach to generating high-quality datasets for fine-tuning a model trained on a high-resource language to perform well in a low-resource dialect. Leveraging generative AI enables reduced effort in data collection, making our approach a promising avenue for future research in low-resource NLP tasks.24 0Item Restricted Modulation of Aryl Hydrocarbon Receptor-Regulated Genes by Methylmercury(University of Alberta, 2024) Alqahtani, Mohammed Ali; Ayman, ElKadiEnvironmental pollution poses a significant threat to public health, with various contaminants contributing to a wide range of adverse health effects. Among these contaminants, ؤ (MeHg) and the aryl hydrocarbon receptor (AHR) ligand 2,3,7,8-tetrachlorodibenzodioxin (TCDD) are particularly concerning due to their persistence in the environment and potent biological activities. Both compounds have been extensively studied for their individual effects, but the potential health risks associated with their combined exposure are less understood. The primary objective of this work was to investigate the individual and combined effects of MeHg and TCDD on AHR-regulated enzymes. This investigation was conducted using the murine hepatoma Hepa-1c1c7 cell line and extended to mouse hepatic and extrahepatic tissues. The effects of MeHg on Ahr-regulated gene expression were examined in the absence and presence of TCDD, along with evaluations of protein expression and enzymatic catalytic activity. In hepatic tissue, both MeHg and Hg2+ inhibited the TCDD-mediated induction of Cyp1a1/1a2 mRNA levels. However, only Hg2+ inhibited the TCDD-mediated induction of CYP1A1/1A2 protein and catalytic activity at posttranscriptional levels, indicating differential modulation by Hg2+ and MeHg. Additionally, the inhibitory role of HO-1 (heme oxygenase-1) on CYP1A activity induced by TCDD was investigated in vitro using the HO-1 competitive inhibitor tin-mesoporphyrin, which partially restored the MeHg-mediated decrease in CYP1A1 activity. In extrahepatic tissues, MeHg exhibited mainly inhibitory effects, particularly decreasing the basal level of Cyp1a1 and Cyp1a2 mRNA and protein, which was more evident at the 24-hour time point in kidneys, followed by hearts. Similarly, when mice were co-exposed, MeHg reduced the TCDD-induced Cyp1a1 and Cyp1a2 expression. However, MeHg potentiated kidney Cyp1b1 mRNA expression, opposing the observed change in its protein level. Exposure to MeHg induces several antioxidant enzymes, including NAD(P)H:quinone oxidoreductase (NQO1), whose expression is regulated by both AHR and nuclear factor erythroid 2-related factor-2 (NRF2). This co-regulation prompted an investigation into which transcription factor primarily orchestrates NQO1 expression upon MeHg exposure. Our findings demonstrate that NQO1 induction by MeHg is, at least in part, mediated by NRF2. In conclusion, the findings of this work reveal an intricate interplay between MeHg and TCDD on AHR-regulated CYP1 enzymes, with notable inhibitory effects that might be significant for procarcinogen metabolism. Varied responses across tissues highlight the potential implications for environmental health.7 0Item Restricted Can diversity in the audit committee mitigate the risk of financial misconduct and corruption? An Overview of Saudi Arabia Regulations.(King's College University, 2024-09-01) Alkhathlan, Norah Rashed; Banerjee, NigelThis dissertation explores the impact of professional diversity within audit committees on mitigating financial misconduct and corruption, focusing mainly on Saudi Arabia's Regulation. Recognizing the critical role of maintaining financial integrity, this study investigates how diverse audit committee compositions might improve financial oversight and decrease unethical behaviors. The research methodology combines a review of past incidents of corporate misconduct with an analysis of the legal framework, complemented by an examination of annual reports from Saudi companies to analyze the expertise and backgrounds of audit committee members. The results indicate that a mix of financial, legal, and industrial expertise within audit committees strengthens their ability to detect and address risks associated with financial misconduct and corruption. The dissertation recommends restructuring audit committees to consist of five members: three with financial skills, one with legal qualifications, and one with industrial experience. This recommended configuration aim to enhance the committee's effectiveness in adhering to legal standards and protect financial integrity. However, acknowledging the varied nature of companies in Saudi Arabia, an exception is proposed for small companies.25 0Item Restricted The Relationship Between Leadership Styles of Nurse Managers and Nurse Turnover in Private Hospital Settings in Saudi Arabia(University of Edinburgh, 2024-08) Ahmed, Daniyah; Haycock-Stuart, ElaineABSTRACT Background: Nursing turnover is a significant and ongoing challenge in healthcare systems worldwide as it impacts patient care. Nursing turnover is often linked to the leadership styles of nurse managers. In Saudi Arabia, where the healthcare sector is undergoing rapid transformation under Vision 2030, effective leadership is increasingly crucial for high quality care. Despite the extensive global research on the influence of different leadership styles on nurse turnover, there is a noticeable gap in understanding this relationship within the context of private hospitals in Saudi Arabia. The review of literature published between 2014 and 2024 examines 19 studies to understand the relationship between nursing turnover and leadership styles. Four key themes were identified and form the basis of literature review chapter. Aim: The proposed study aims to examine the relationship between nurse managers' leadership styles and nursing turnover within the private Saudi hospitals context. Methods: A descriptive correlational research design will be implemented at the Saudi German Hospital, Dr. Suliman Fakeeh Hospital, and International Medical Centre (IMC) in Jeddah, Saudi Arabia. Using stratified random sampling, 50 nurse managers and 250 nurses will be selected. Data will be collected via surveys distributed through WhatsApp and email, the Multifactor Leadership Questionnaire (MLQ-5X), with the addition of a Sociodemographic section and the Anticipated Turnover Scale (ATS). Both descriptive and inferential statistics will be employed for data analysis. Implications: The findings will inform the development of targeted leadership training programmes to enhance nurse retention and job satisfaction. The study will also provide evidence-based recommendations for policy development and influence nursing curricula. Additionally, it will lay the groundwork for future research on leadership styles and nursing turnover.11 0Item Restricted What Do Invesitors Care About in Cryptocurrency Markets? Evidence from ESG Ratings and NFTs(University of East Anglia, 2024-09) Alsultan, Sarah Abdulrahman; Markellos, Raphael; Kourtis, ApostolosWhile cryptocurrencies have seen limited adoption as a medium of exchange, they have been recognised as a new class of investment assets. A broader range of investors, including institutional investors, has shown growing interest in cryptocurrency and digital assets. Therefore, this thesis contributes to the literature by thoroughly examining digital technologies as investment assets through three empirical studies. The first study explores whether investors prefer blockchains with strong Environmental, Social, and Governance (ESG), using a novel dataset of blockchain ESG scores. The findings reveal a time-varying preference for high-ESG blockchains. The top-rated blockchains outperform lower-rated ones during favourable market conditions and optimistic market sentiment but underperform during times of negative sentiment. Our findings also indicate that high-ESG blockchains exhibit higher market volatility. Furthermore, governance and environmental factors have the strongest influence on investor preferences among the three ESG dimensions. The second study examines NFTs as a relatively new asset class that is not yet fully understood, particularly in terms of risk modelling. It evaluates and compares the forecasting performance of various GARCH models in estimating NFT market volatility across different time horizons. The selected models include GARCH(1,1), IGARCH(1,1), EGARCH(1,1), GJR- GARCH(1,1), and TGARCH(1,1). The dataset comprises three major NFT categories, six NFT token platforms, and major cryptocurrencies, including Bitcoin and Ethereum. Empirical evidence shows that different models perform better depending on the asset type and forecast horizon. The findings highlight the highly volatile nature of NFT markets. The third study assesses the impact of visual attractiveness on NFT market prices. Prior art literature has demonstrated the role of aesthetics in influencing art prices. Given the similarities between NFTs and traditional art, this study investigates whether aesthetics similarly impact NFT prices. The empirical analysis focuses on one of the largest NFT collections, CryptoPunks, by applying a hedonic pricing model. We employ quantitative aesthetic measures to capture aspects of NFT art, including colourfulness, brightness, colour intensity, and texture. Our results reveal a significant impact of visual aesthetics on determining NFT prices. The results indicate that more colourful and visually complex NFTs are associated with higher prices, while brighter and more saturated NFTs are associated with lower prices.11 0Item Restricted Optical Wireless Communication-Enabled Data Centre Networks(Abrar Alhazmi, 2024-12-03) Alhazmi, Abrar; Elmirghani, Jaafar; El-Gorashi, TaisirData Centres (DCs) are witnessing significant traffic surges due to the increasing popularity of cloud computing-based applications. To handle this a surge, Data Centre Network (DCN) designs are required to provide high throughput, reconfigurability, scalability, energy efficiency, and low latency. To satisfy these requirements, technological and structural advancements and effective placement of workload are required in DCs. Optical Wireless Communication (OWC) offers potential solutions for the challenges faced by DCNs by enabling improved scalability and flexibility, reducing wiring complexities, and lowering the power consumption while providing high bandwidth. Passive Optical Networks (PONs) have also been considered for DCs as they offer high bandwidth, flexibility, cost-effectiveness, and energy efficiency due to the use of passive components. In this thesis, we propose incorporating OWC and PON technologies into next generation spine-and-leaf DCNs. OWC is used to connect the racks of a DC through Wavelength Division Multiplexing (WDM) Infrared (IR) transceivers that are placed at the top of the racks and at distributed Access Points (APs) in the ceiling. Each transceiver at a rack is connected to a leaf switch that connects the servers within the rack. The transceivers use Angle Diversity Transmitters (ADTs) and Angle Diversity Receivers (ADRs) to enable connecting each rack with all APs. We propose two PON designs to replace the spine switches by providing passive connectivity between APs and between APs and the Optical Line Terminal (OLT) that connect the DCs to external networks. The first PON design uses Arrayed Waveguide Grating Routers (AWGRs) to connect APs to each other and connect APs to the OLT while the second PON design uses Network Interface Cards (NIC) to connect APs to each other and to connect subsets of the APs to the OLT. In addition, we present channel modelling for the uplinks and downlinks for a DC with eight racks and ADTs with ADRs showing data rates between 10 and 20 Gbps for uplink and between 7.5 and 16 Gbps for downlink. Additionally, we study the impact of air turbulences resulting from the temperature variations in temperature on the channel performance. Moreover, we optimise the routing and wavelength assignment in the AWGR-based PON using Mixed Integer Linear Programming (MILP). Furthermore, we develop a MILP model with the objective to maximise the data rates in both the uplink and downlink directions and determine the optimal paths between the racks and between racks and the OLT based on the achievable data rates. We benchmark the power consumption of the proposed OWC-PON-based spine-and-leaf DC designs against the traditional spine-and-leaf DC. Considering eight racks, the results show that in comparison to iii traditional spine and leaf architectures, the AWGR-based architecture minimised the power consumption by 50%, and the AP-to-AP architecture minimised it by 46%. Furthermore, we further develop a MILP model to optimise Virtual Machine (VM) placement in the proposed OWC-PON-based spine-and-leaf DCs architectures to minimise the power consumption of networking and processing. Our results show that jointly minimising the networking and processing power consumption, decreases the networking power consumption by 75% compared to minimising the processing power consumption only. In this work, the proposed model serves as a pivotal contribution., providing a valuable framework for evaluating and benchmarking different architectures and settings.8 0Item Restricted Timekeeper: Advancing Circadian Research with GST-Tagged Per3 Protein(The University of Edinburgh, 2024) Alanezi, Sarah Abdullah; Arribas, RaquelThe Per3 gene plays a crucial role in regulating circadian rhythms, profoundly impacting sleep-wake cycles and metabolic processes. Despite its biological significance, the expression and purification of Per3 have presented substantial challenges, often resulting in low yields and poor solubility. This study tackles these obstacles by employing innovative cloning and expression techniques, particularly utilizing a GST-Per3long to enhance solubility and purification efficiency. We designed primers incorporating homology regions complementary to restriction enzyme-digested ends and employed the In-Fusion cloning method to integrate the Per3 gene into the p3E plasmid vector with high precision. The transformation efficiencies were remarkable, with colony counts reaching 2.292 x 10^8 colonies per μg of plasmid DNA. PCR amplification confirmed the successful integration of the Per3 gene, with distinct bands observed at the expected size of 1143 bp, which was further confirmed by DNA sequencing. Protein expression trials identified 25°C as the optimal temperature, significantly improving the yield and solubility of the GST-tagged Per3 protein. Subsequent purification through GST Affinity chromatography and gel filtration chromatography yielded a highly pure protein, as confirmed by SDS-PAGE and native gel electrophoresis. Although the initial yield was modest, the high purity of the purified protein provides a robust foundation for future functional and structural studies. This study not only establishes a reliable protocol for Per3 expression and purification but also opens avenues for investigating the interactions of Per3 with other circadian proteins, such as CRY and BMAL1, to determine their mutual exclusivity and relative affinity. These interactions are crucial for understanding the biological role of Per3 in fine-tuning the circadian clock. Future work should focus on optimizing expression conditions to further increase yield and investigate the intricate biological activity of the Per3 protein within the circadian network.18 0