SACM - United Kingdom
Permanent URI for this collectionhttps://drepo.sdl.edu.sa/handle/20.500.14154/9667
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Item Restricted An Investigation of a New Pulse Echo Ultrasound Scanner, the Bindex®, for the Assessment of Osteoporosis in an English Population(Saudi Digital Library, 2025) Algahtani, Abdulkareem; Knapp, Karen; Fulford, Jonathan; Meertens, Robert; Strain, DavidWith its characteristic decrease in bone mass and deteriorated bone structure, osteoporosis increases fracture risk, resulting in a decreased quality of life, increased morbidity and mortality. To avoid fractures and minimise long-term health consequences, early diagnosis is key in terms of providing timely preventative healthcare treatments and interventions. Dual energy X-ray absorptiometry (DXA) remains the gold standard for assessing bone mineral density (BMD), but its limited accessibility and high cost restrict its use in many settings. Bindex®, a portable and radiation-free device using pulse-echo ultrasound, presents a promising alternative. Comparing its diagnostic performance to DXA may support its utility as a point-of-care tool for early osteoporosis detection and triage. This thesis assesses the diagnostic utility of the Bindex® scanner, as a convenient alternative to DXA. Participants aged 40 and above were recruited, based on diabetes status, fracture history, and general health. Bone health was assessed using the Bindex® and compared with DXA. Bindex® was used to calculate the Density Index (DI) at the tibia and radius, while DXA scans were performed at the lumbar spine, both femurs, right knee and right forearm. Statistical analysis included precision testing, correlation and agreement using Pearson’s correlation and Bland Altman plots, and diagnostic accuracy through ROC curve analysis. Linear regression was applied to assess age related changes, and participant acceptability of both scanning methods was also evaluated. The study demonstrated moderate to strong correlations between Bindex® DI measurements and DXA-derived BMD, particularly at the femoral neck. A key finding was that Bindex® showed good diagnostic performance in identifying individuals at risk of osteoporosis, with sensitivity improving to 100% when a population-specific DI threshold of 1.056 g/cm² was applied. Precision analysis confirmed acceptable inter- and intra-operator reliability. Age was found to have a significant but modest association with both DI and BMD values. Participant feedback indicated a high level of acceptability for Bindex® scanning, supporting its potential as a practical and accessible tool for osteoporosis screening, particularly in primary care settings.4 0Item Restricted Characterisation of the Extracellular Vesicles Role in the Mediation of Embryo-Maternal Communication at the Time of Implantation(Saudi Digital Library, 2025) Bafana, Noor; Fazeli, AlirezaThe pregnancy rates after employing Assisted Reproductive Technologies (ART) treatments are relatively low. The most common cause of pregnancy failure appears to be impaired uterine receptivity and inefficient embryo-maternal communication. In recent years, membranous nanoparticles secreted from eukaryotic cells, known as Extracellular Vesicles (EVs), have been identified as essential mediators of intercellular communication and regulators of reproductive processes, including implantation. However, their role in embryo-endometrium communication during early implantation is not fully understood. This thesis investigates the role of EVs in bidirectional embryo-endometrial communication during early implantation, focusing on the impact of a non-receptive endometrium. An in vitro co-culture model, utilising 3D trophoblast spheroids and endometrial monolayers, simulated the dynamic interactions during implantation. The impact of EVs on embryo-maternal communication was investigated at both functional and transcriptomic levels, including the influence of endometrial EV miRNA cargo. Findings revealed a critical interplay between preimplantation embryo surrogates and the receptive endometrium. Receptive endometrial cells responded significantly to trophoblast EVs, and trophoblast spheroids responded uniquely to receptive endometrial EVs. These findings suggest that the receptive endometrium establishes an environment that actively supports embryo development and enhances implantation potential. Conversely, our findings highlighted the potential detrimental impact of a non-receptive endometrium. EVs from a non-receptive endometrium may impair early embryo development and function. Embryo-derived EVs may struggle to elicit a response from compromised endometrial cells. This disrupted communication may contribute to recurrent implantation failure, where inadequate endometrial receptivity and compromised embryo-maternal dialogue underlie repeated failures. In additional work, EVs derived from bovine milk were investigated as a potential natural source of EVs. Their role in enhancing trophoblast spheroid binding and the effect on the trophoblast transcriptome were evaluated, with a focus on milk EV miRNAs. The results demonstrated the promise of bovine milk EVs as a potential therapeutic avenue for improving implantation outcomes.4 0Item Restricted How Flooding is Putting Historical Heritage at Risk(Saudi Digital Library, 2024-08-29) Hanbuli, Waad ALI; Duarte, Natalia VillamizarUrban Flash Flooding is referred to excessive rainfall for a time period of more than six hours in an urban area which has hard surface development stopping the water to soak in ground resulting in to water running through roads and streets and damaging the overall urban land. As per the recent study by world bank, it has been revealed that urban areas are becoming more vulnerable to urban flooding and the key reasons behind are rapid urbanization, climate change and lack of resilient urban management. Floods in the kingdom of Saudi Arabia is considered the most horrific among all-natural disaster and accounted for 34% of death tolls. Emissions from transportation and urban development significantly aggravate the problem and the city of Jed dah is experiencing extreme flash floods causing loss of lives and damage to property. Considering the ancient importance of the Jeddah Historic area, Al-Bald, it suggests the need to conduct research that aims to revitalize this area with innovative urban design techniques to protect it from this horrific incident while preserving its historic character. Moreover, analysis like flood risk analysis, flood susceptibility analysis as well as rainfall analysis have been carried out to analyse the vulnerability of the study area to flash flooding. The analysis revealed that the area is more likely to be impacted by floods during extreme rainfall events. This demands for a sustainable urban design that increase the sponginess of the area to avoid water accumulation. Resultantly, the multilevel strategy-based design optimization incorporates the sponge city theme. Therefore, including wetland, roof gardens, rainwater garden as well as permeable pavements in the existing design of the historic area, which reduces the area’s overall vulnerability to flood and rain-related calamities and serves as a model for comparable urban design practices. This study advances flood prevention in the realm of urban design by providing a broad framework for architectural and urban design.8 0Item Restricted Exploring zero-gap Water Electrolysis Technologies: Benchmarking, Evaluation, and Comparative Analysis(Saudi Digital Library, 2025) Faqeeh, Abdulhai; Symes, MarkWater electrolysis is a promising process to produce green hydrogen, a sustainable and environmentally friendly fuel and a crucial chemical used in numerous industrial applications. Zero-gap water electrolysers have become a key technology for green hydrogen production, mainly due to their high efficiency and hydrogen purity and their rapid response to a wide range of operating conditions and intermittent electricity, facilitating their coupling with renewable energy sources. In Chapter 1, the fundamentals and history of the water electrolysis process are discussed, and the low-temperature water electrolyser technologies are introduced. Moreover, the key evaluation parameters of water electrolysis electrocatalysts are reported. In Chapter 2, all the experimental techniques used throughout this work are introduced and discussed, covering their theoretical background and operation principles. In Chapter 3, a standard anion exchange membrane water electrolyser, a type of zero-gap electrolyser design, is developed and optimised to be used as a universal testbed for evaluating novel electrocatalysts and other components of (anion exchange membrane) water electrolysis. The benchmark is developed because of the absence of a reliable evaluating protocol due to variations in testing conditions and water electrolyser components across studies, obstructing a comprehensive and cohesive comparison of new electrocatalysts (or other components of anion exchange membrane water electrolysis technology). The construction and operation of the standard water electrolyser are described in detail. In addition, 3D drawings of the water electrolyser components are provided (located in the University of Glasgow’s open access data repository, https://researchdata.gla.ac.uk/1672/), enabling others to construct and operate their own identical flow cell. In Chapter 4, the flow cell introduced in Chapter 3 is used to evaluate a new commercially available polymer membrane as an alternative proton exchange membrane to Nafion and Aquivion membranes, which have been in short supply recently. The performance, stability, and hydrogen crossover characteristics of the new membrane is evaluated and compared to those of the Nafion and Aquivion membranes. In Chapter 5, the standard water electrolyser developed and optimised in Chapter 3 is adopted to evaluate a radiation-grafted anion exchange membrane supplied by a research team based at the University of Surrey. The membrane is assessed and compared to a commercial anion exchange membrane (FAA-3-50).4 0Item Restricted Responsibility for Online Harms: A Critical Analysis of Cyber Governance in Saudi Arabia(Saudi Digital Library, 2025-03) Alsaiedi, Yara M; Basu, Subhajit; Walker, CliveThis 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.3 0Item Restricted In the Wake of Recent Global Health Emergencies, how has International law Adapted to Manage Such Crises, and what Further Developments are Needed(Saudi Digital Library, 2025-07-29) DESCRIBE; MOHAMADabstract The inception of international law (IL) has heightened the capability of the U.N. member states to tackle pandemics and epidemics. IL evolution has been linked to various events, such as the signing of treaties to end wars and establish a peaceful society. This study aims to understand how IL has adapted to manage global health crises. Moreover, it discusses the areas that need further development to make IL more effective in responding to and dealing with issues around future pandemics after the COVID-19 pandemic. Global health crises such as Ebola virus diseases (EVD) and the COVID-19 virus have negatively influenced the role of the U.N. COVID-19 pandemic exposed the weakness of the current IL. The International Health Regulations 2005 (IHR 2005) plays a role in preventing pandemics and epidemics. The COVID-19 pandemic emergence required member states to adopt measures that comply with the IHR 2005 regulations to prevent the spread of the virus. However, it is believed that IL enforcement during the recent pandemic was strengthened by the need to protect the right to life and right to health. However, imposing the preventive measures limited various civil and political rights, especially the right to peaceful gathering and speech, the right to privacy, the right to participate in the electoral process, and the right to just and fair hearing. Policymakers and U.N. bodies declare that the desire to protect the right to life and health should drive nations to implement measures to inhibit disease spread. Nevertheless, the IL framework has various shortcomings that need strengthening to improve the UN/WHO preparedness to tackle future global public health crises. Keyword: International Law, International Health Regulations, United Nations, World Health Organisation, COVID-19 Pandemic, customary international law9 0Item Restricted CEO characteristics and Real Earnings Management(University of Southampton, 2025) Alotaibi, Mohammed; Vithana, Krish; Tingbani, IshmaelReal earnings management (REM) behaviour can be influenced by external factors, including agency cost, political costs, and compensation motivations. Consequently, prior research investigated REM with respect to these aspects. While previous research has explored REM behaviour within these contexts, there has been a lack of attention paid to how a CEO's characteristics might play a role in these intricate situations. This thesis addresses this gap by demonstrating how a CEO’s traits interact with these external factors to shape REM practices, and the three papers are interconnected by this viewpoint. This method not only addresses gaps in the current body of literature but also underscores the significance of examining the decision-making processes of managers regarding REM by taking into account both internal CEO characteristics and external factors. Therefore, the first study investigates how narcissistic CEOs influence REM taking into account how this dynamic may change under Corporate Social Responsibility (CSR). Namely, this study set out how the interaction between CSR and CEO narcissism influences REM behaviour. To answer this question, a sample of firms listed on the S&P 500 Index from 2008 to 2020 was used. In accordance with previous studies, the first paper reveals a negative relationship between CSR and REM and a positive relationship between CEO narcissism and REM. Interestingly, the interaction term reveals that CSR improves earnings quality by reducing this positive association between CEO narcissism and REM. This is a consequence of the reduced information asymmetry and increased involvement of stakeholders that these CSRs bring, as well as the ability of CSR to redirect the interpersonal strategies of the CEO narcissism system, leading narcissistic CEOs to engage more in CSR and less in REM in order to improve the firm's image and achieve a sense of pride and dominance. The second paper examined whether the relationship between government contract and REM is conditional upon the ability of managers. While prior studies have examined political cost through government contracts as a factor determining earnings management (EM) behaviour in politically sensitive firms, this study demonstrates that managerial characteristics interact to determine EM behaviour. A sample of 162,756 firm-year observations of US companies in COMPUSTAT from 1980 to 2020 was examined. This study found that due to the monitoring that comes with government contracts, contractors engage in REM as a less detectable EM method. However, REM activity is reduced if the contractor firm is led by highly able managers. The third paper investigated whether the relationship between industry tournament incentives and REM is influenced by the ability of managers. The inconsistent results of previous studies that have examined the relationship between industry tournament incentives and REM have served as motivation for this study. The findings indicate that firms are more likely to engage in REM as a consequence of CEO industry tournament incentives. However, the level of involvement in REM reduces when the company is managed by high-ability managers. This finding suggests that managerial characteristics influence EM behaviour, highlighting the importance of employing high-ability managers to mitigate any potentially unethical consequences. This finding was achieved by studying a sample of 26,255 firm-year observations covering all US firms in COMPUSTAT from the years 1992–2020. The findings are robust, involving a number of sensitivity tests. This research empirically contributes to the EM literature by indicating that the influence of external factors (CSR, political connection, and industry tournament incentives) is subject to the CEO's characteristics.7 0Item Restricted What aspects do flexible office companies consider in the design of their offices?(Saudi Digital Library, 2024-08-01) Saifislam, Miga; Derakhshanalavijeh, RoyaIn an era where workspaces are rapidly evolving, the design of flexible office spaces has become pivotal in shaping the future of work. Although extensive research exists on topics like ergonomics and innovative work approaches, there appears to be a significant gap in understanding whether and how flexible office companies are incorporating these insights into their design strategies. This paper addresses the research question: 'What aspects do flexible office companies consider in their office designs?' The study aims to identify the key aspects these companies should consider, and to propose innovative design strategies that address these factors. Drawing on interviews with both practitioners and users, the research highlights the limitations inherent in the standardised, one- size-fits-all approach to designing spaces. Findings from the study underscores the need for adaptability and flexibility, operational and management efficiency, as well as the importance of considering employee well-being and sustainability to ensure current and future success. In doing so, the research urges a paradigm shift towards innovative and personalised design strategies that align with evolving needs of modern workplaces.7 0Item Restricted Plasmonic Effects in Porous Silicon for Applications in Optoelectronics and Medical Physics(Saudi Digital Library, 2025-06-03) Bokhari, Anas; Kaplan, AndreyPorous silicon (pSi) has attracted considerable attention due to its unique structure, high surface area, and optical properties, which make it suitable for sensors, photonic devices, and medical applications. However, its natural photoluminescence is weak, its catalytic performance is limited, and its conductivity under light is relatively low. This project aimed to overcome these limitations by embedding gold nanoparticles (AuNPs) into the porous structure to take advantage of plasmonic effects, particularly localised surface plasmon resonance (LSPR). To achieve this, I used four different fabrication methods: anodization, spin coating, ultrasonic impregnation, and electroless plating. These approaches allowed the AuNPs to be positioned both on the surface and deep inside the pores of the silicon. The result was a noticeable improvement in several areas, including enhanced photoluminescence, stronger photothermal effects, more efficient hydrogen production from methanol, and electrical conductivity under light exposure. I used techniques such as FTIR, Raman spectroscopy, and photoluminescence measurements to study how the plasmonic effects influenced the material’s properties. Photocatalytic activity was assessed by measuring hydrogen generation, and photoconductivity tests were carried out to evaluate the potential for light-based electronic applications. What makes this work stand out is that it focuses on embedding gold nanoparticles inside the nanochannels, rather than just on the surface, which most studies have done. This internal placement leads to stronger light material interactions and better performance across multiple functions. These findings open up new possibilities for using gold-impregnated porous silicon in advanced technologies such as optical sensors, hydrogen fuel systems, and medical treatments like photothermal therapy.12 0Item Restricted ‘Evolving Dynamics of Sustainability Disclosure in Saudi Arabia: A Documentary Analysis’(Saudi Digital Library, 2024) Azouari, Shatha; Bhuiyan, FarukThis study investigates how the sustainability disclosure practices of Saudi Arabian companies have evolved and how they are influenced by Saudi Vision 2030, international pressures and local regulatory frameworks. This study is built upon the stakeholder theory to gain an in-depth understanding of the impact of different stakeholder requirements on sustainability disclosure. It investigates the extent to which this reporting is transparent and accountable. The study adopts a qualitative methodology focusing on sustainability and annual reports from 18 Saudi Arabian companies in 9 sectors, including energy, finance, healthcare, and telecommunications. The selected companies were chosen based on their market value and the availability of relevant sustainability disclosures for the years 2022 and 2023. The key findings indicate that significant progress has been made in advancing sustainability disclosures in Saudi Arabia. This is through the incorporation of sustainability practices into corporate strategies with a primary focus on Vision 2030 objectives, Tadawul's regulations and growing international pressures. While certain sectors, particularly energy, utilities, materials, and finance, show significant progress in their approach, healthcare and insurance lag in ESG integration and international standards, highlighting a need for improved governance frameworks and more consistent regulatory oversight. As a new and interesting finding, the study underscores the importance of Vision 2030 and Tadawul Disclosure Guidelines as catalysts for change and calls for enhanced capacity-building and regulatory support to ensure that Saudi companies can meet national and international sustainability expectations. The study provides theoretical and managerial insights into the broader discourse on corporate transparency and sustainable development, offering invaluable insights for academic communities, managers, and policymakers in Saudi Arabia.2 0