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 into the factors influencing decision making regarding the management of carious primary teeth under general anaesthetic(Saudi Digital Library., 2026) Almohammed, Bushra Abdulaziz; Barber, Sophy; Balmer, RichardCaries in primary teeth remains a common reason for Paediatric Dental General Anaesthesia (PDGA) in the United Kingdom (UK). Different treatment options are available for carious primary teeth under general anaesthesia (GA), ranging from restorative treatments to extraction. Variation in treatment planning has been observed in practice, but the reasons underlying these decisions are not well understood. Aim: To explore the factors that influence paediatric dentists’ decision-making, when planning treatment for children with carious primary teeth under GA in the UK. Method: A qualitative cross-sectional study, informed by an interpretivist- constructivist approach. using focus groups was conducted with paediatric speciality trainees, specialists and consultants within the UK, who were all recruited through the British Society of Paediatric Dentistry (BSPD). Focus groups were conducted online and recorded, then transcribed. Data were analysed using reflexive thematic analysis to explore clinicians’ reported views and experiences of treatment planning carious primary teeth under GA. Results: Nineteen participants took part in three focus groups. Participants described variation in treatment planning under GA, which they related to different treatment philosophies, training backgrounds and organisational arrangements. Modified Hall technique, was the treatment of choice, when aiming to preserve teeth. Participants described reluctance to provide vital pulp therapy (VPT) under GA, despite supportive evidence-based guidelines, because of predictability concerns and risk of repeat GA. Decision making was reported to be influenced by experience, workplace hierarchy and service pressures, including waiting lists, workforce limitations and the type of GA list available. Participants also emphasised the importance of parental expectations, shared decision-making and perception of families’ ability to maintain oral health. Conclusion: Treatment planning for carious primary teeth under GA was described to be influenced by interactions between clinical, family and service-related factors. The findings provide insights into how UK paediatric dentists explain their decision-making and highlight the importance of aligning treatment planning with current evidence, supporting shared decision-making and address organisational barriers to comprehensive care.12 0Item Restricted The Legal Framework for Public-Private Partnerships (PPPs) as an economic, social, and environmental Sustainability Transition in Saudi Arabia(Saudi Digital Library, 2026) Alluhidan, Nouf Ahmed; Chimia, Annamaria; Trepte, PeterThis research examines the legal framework for public–private partnerships (PPPs) in the Kingdom of Saudi Arabia as a sustainable transition mechanism across three levels: social, economic, and environmental, by analysing all national regulations applicable to PPPs. The private sector could play a significant role in societal prosperity through its direct and indirect effects, making PPPs a crucial component in building sustainable infrastructures in countries. This has led the United Nations to recognise the need for all parties, including governments and the private sector, to cooperate in an international partnership to achieve the Sustainable Development Goals (SDGs). However, PPPs cannot effectively contribute to the SDGs unless governments implement internal legal reforms and enhance the legal environment. Therefore, the purpose of this research is to examine the current legal framework for PPPs under Saudi law and assess the extent to which it supports the Kingdom’s Vision 2030 and the SDGs. Numerous PPPs have recently been adopted in the country for the first time, with many more in the tendering process at various stages. In this regard, due to the recent adoption of PPPs, there was a strong need to conduct interviews to investigate their application across different sectors in the country. Semi-structured interviews were conducted with government procurement officials, policymakers, and other experts in the field to determine the extent to which PPPs can serve as effective instruments for achieving sustainability in Saudi Arabia. PPPs clearly offer various advantages, including leveraging private sector expertise and funding, enhancing quality, fostering innovation and local content, and enabling risk sharing. However, challenges remain, such as unstable environmental and social regulations, a lack of environmental and social requirements in contracts, negative impacts on public employees, and a wide number of applicants in the short term. In conclusion, the legal framework governing PPPs is critical to ensuring Saudi Arabia’s efforts to achieve its Vision 2030 objectives, some of which align with international standards, while others require serious consideration and reform.62 0Item Restricted The Role of the NLRP3 Inflammasome in PCOS: A Possible Novel Association(Saudi Digital Library, 2026) Alenezi, Salih Atalah R; Amer, SaadAbstract Background: Polycystic ovary syndrome (PCOS) is a common endocrine–metabolic disorder of women of reproductive age, characterised by ovulatory dysfunction, hyperandrogenism, and frequently accompanied by obesity and insulin resistance. Increasing evidence suggests an association between PCOS and chronic low-grade inflammation. The NLRP3 inflammasome is a cytosolic protein complex of the innate immune system that activates inflammatory cytokines (notably IL-1β and IL-18) in response to metabolic stress. As NLRP3-driven inflammation has been implicated in obesity, diabetes and related disorders, this thesis explored the hypothesis that NLRP3 inflammasome activity contributes to the pathophysiology of PCOS. The aim was to evaluate this potential association through systematic reviews, meta-analyses and experimental studies. Methods: Three systematic reviews with meta-analyses were conducted. The first examined NLRP3 and its components (Caspase-1 (CASP-1), ASC, IL-1β) in adipose tissue or blood from obese versus non-obese individuals, and in women or animal models with PCOS. The second assessed the impact of diet-induced weight loss in PCOS on circulating inflammatory markers (CRP, IL-6, IL-1β, TNF-α) and reproductive hormones (testosterone, androstenedione, LH, SHBG). The third evaluated the impact of elevated body mass index (BMI) on pregnancy outcomes and complications in women with PCOS undergoing in vitro fertilisation (IVF). Standard systematic search methodology and quality appraisal tools (Cochrane/NOS) were applied, and pooled analyses were performed using RevMan software where appropriate. Original laboratory studies were also undertaken to investigate inflammasome activity in adipose tissue. Gene expression of NLRP3, IL-1β, CASP-1, and ASC was measured using qPCR and protein expression of NLRP3 by Western blotting in visceral and subcutaneous adipose tissue from PCOS and non-PCOS women. In addition, circulating IL-1β and IL-18 were assessed by ELISA. Key Findings: NLRP3 in Obesity and PCOS (Systematic Review, Chapter 2): Meta-analysis demonstrated that the expression of NLRP3 inflammasome components in adipose tissue was significantly higher in obese individuals compared with non-obese controls. Specifically, NLRP3, ASC and IL-1β were elevated in obese adipose tissue. Although the number of human studies was limited, most studies of women with PCOS and rodent PCOS models also reported upregulation of NLRP3 and its associated components, supporting a potential link between obesity, PCOS and inflammasome activation. Weight Loss, Inflammation and Hyperandrogenism (Systematic Review, Chapter 3): Analysis of nine studies (n=286) evaluating dietary weight loss in PCOS showed that modest weight reduction significantly improved inflammatory and hormonal profiles. Circulating CRP, IL-6 and TNF-α levels decreased post-intervention. Additionally, androstenedione and LH levels were reduced, whilst SHBG increased. These findings indicate that dietary weight loss seems to ameliorate both chronic inflammation and hyperandrogenism in PCOS. BMI and IVF Outcomes in PCOS (Systematic Review, Chapter 3): Analysis of nineteen studies (n=7680) demonstrated that elevated BMI in women with PCOS undergoing IVF was associated with adverse reproductive outcomes. PCOS women with normal BMI had higher odds of clinical pregnancy and live birth, while high BMI was associated with increased risk of miscarriage, gestational diabetes, and gestational hypertension. These findings highlight the significant impact of metabolic status on clinical reproductive outcomes in PCOS. Adipose Tissue Inflammasome Gene Expression (Chapter 5): Contrary to the initial hypothesis, CASP-1 gene expression was significantly higher in non-PCOS versus PCOS women across all adipose depots (VAT and SAT). On the other hand, expression of NLRP3, IL-1β and ASC did not differ significantly between women with and without PCOS. These findings suggest a more complex role for the NLRP3 inflammasome in PCOS with a more nuanced regulatory pattern than previously assumed. Adipose Tissue Protein Expression (Chapter 6): At the protein level, NLRP3 expression in the combined subcutaneous and visceral adipose tissue, and in visceral adipose tissue alone, was significantly higher in non-PCOS versus PCOS women, again contradicting the original hypothesis. Plasma IL-1β was undetectable and IL-18 was measurable but not significantly different between groups. These data mirrored the transcript findings, raising the possibility of a more complex inflammatory mechanism in PCOS. Conclusions and Implications (Chapter 7): Taken together, this thesis provides novel insights into the association between the NLRP3 inflammasome and PCOS. The systematic reviews demonstrated that obesity and PCOS are generally accompanied by activation of inflammasome pathways, and that weight loss can reduce both inflammation and androgen excess, and that elevated BMI is associated with poorer reproductive outcomes, including those following IVF. However, the original experimental studies revealed unexpected findings, with higher CASP-1 and NLRP3 expression in non-PCOS women, suggesting that inflammasome regulation in PCOS may be more complex than previously assumed. Potential explanations include compensatory downregulation, metabolic influences such as hyperinsulinemia, or the involvement of alternative inflammasome pathways. In conclusion, this work advances understanding of inflammatory mechanisms in PCOS by highlighting a potential but intricate role for the NLRP3 inflammasome. These findings underscore the need for future studies to disentangle the regulatory interactions between metabolism, immunity and reproductive dysfunction in PCOS, and to assess whether targeted metabolic or anti-inflammatory therapies might have clinical utility in managing this syndrome.5 0Item Restricted On the Human Neuromuscular Junction: Anatomical Features and the Effects of Increasing Age.(Saudi Digital Library, 2026) Ramadan, Abdullah; Gillingwater, TomThe neuromuscular junction (NMJ) is a specialised chemical synapse that mediates communication between motor neurons and skeletal muscle fibres, playing a critical role in voluntary motor control. Despite its functional importance, our understanding of human NMJ morphology remains limited, particularly in terms of ageing and nano-structured details. This thesis addresses key gaps in human NMJ research through investigating anatomical characterisation, age-associated structural changes in human upper limb muscles, and applying a new super-resolution (SR) technique to reveal fine structures. In the first part of this study, NMJs were systematically analysed in upper limb muscles obtained from healthy adult donors. Using immunohistochemistry (IHC) staining and confocal microscopy, a baseline morphological profile was established. The second part explored age-related changes of the NMJ, focusing on terminal Schwann cells (TSCs) and voltage-gated sodium channels (NaV1.4) besides the basic presynaptic and postsynaptic elements. Aged NMJs exhibited subtle structural alterations, including changes in TSCs architecture and disruption in NaV1.4 expression, suggesting progressive synaptic decline with preserved overall integrity. These findings indicate that human NMJ ageing changes diverge from the rodent scenario, where the latter reveals a progressive structural denervation in response to ageing. The final part of the thesis introduced and validated Expansion Microscopy (ExM) as a novel technique for NMJs imaging at nanoscale resolution. ExM results are enabled by VIII isotropic tissue expansion, capturing synaptic details in three-dimensional visualisation. As a recent SR technique, the ExM is cost-effective, accessible and applicable. Collectively, these three studies represent the aims of the thesis, provide a comprehensive and novel anatomical account of the human NMJ. They offer critical reference data, reveal patterns of structural ageing, and establish a powerful imaging platform for future research4 0Item Restricted Mitigating Distribution Shift and Label Noise in Deep Neural Network Based Network Intrusion Detection Systems(Saudi Digital Library, 2026) Alotaibi, Fahad Mastor T; Maffeis, SergioDeep Neural Network (DNN)-based Network Intrusion Detection Systems (NIDS) have shown strong performance on offline benchmarks under controlled conditions. However, real-world deployment remains challenging. This thesis focuses on two key challenges: (i) distribution shift, in which benign traffic evolves and attackers continuously devise new strategies; and (ii) label noise, arising from imperfect automated labelling of large volumes of network traffic. To address these challenges, the thesis first provides a critical literature review and develops a structured taxonomy of techniques for handling distribution shift in NIDS and label noise in both NIDS and malware datasets. Building on these insights, it introduces three frameworks. Mateen adapts one-class anomaly detection to evolving benign traffic by combining selective labelling with an ensemble-based mechanism that identifies and responds to shifts with minimal manual effort. Rasd extends multi-class NIDS to detect and integrate newly emerging attack classes, substantially reducing labelling costs through strategic selection of a small, informative, and diverse subset. SLB mitigates label noise by partitioning the dataset into clean and noisy sets and iteratively refining both the model and the labels. Each framework is evaluated extensively across multiple datasets and compared with state-of-the-art baselines. Mateen improves the anomaly-detection F1 score by 4.13% under a light-shift scenario (CICIDS2017) and by 72.6% under an extreme-shift scenario (Kitsune). Rasd increases the novel class detection F1 score by 6.83% on CICIDS2017 and by 19.21% on CSE-CIC-IDS2018. SLB reduces the noise rate in CICIDS2017 (with 30% injected random noise) to below 1.2% and outperforms the vanilla baseline by 11.83% in macro F1. This thesis serves as a reference for researchers and practitioners in cyber security and artificial intelligence. Beyond its literature review and taxonomy, it contributes three frameworks that collectively enhance the robustness of DNN-based NIDS, achieving state-of-the-art results on the evaluated benchmarks.5 0Item Restricted Women’s Legal Empowerment in Employment in Saudi Arabia(Saudi Digital Library, 2026) Barnawi, Rehab Abdullah O; Shaheed, Ahmed; Maranlou, SaharLegal empowerment is an approach adopted by international organisations, civil society groups, and governments interested in development to improve the lives of the disadvantaged. In KSA, women's employment status warrants attention, as the country has consistently shown low female participation in the economy for decades. The situation is currently evolving due to new legal reforms that promote women's access to employment across various sectors, a development considered culturally revolutionary. This paper advocates examining the situation from a socio-legal perspective and proposes legal empowerment strategies as alternatives to the traditional rule-of-law orthodoxy. It particularly emphasises understanding Saudi women's agency and explores how they can effectively engage with the law to advocate for the promotion of their rights and interests. It employs the CLEP’s framework, feminist and developmental approaches towards women’s legal empowerment, recognising that legal reforms alone are insufficient to encourage women's full participation in the workforce. The study proposes strategies to empower women to overcome legal, cultural, and social barriers. The research is grounded in primary data collected through a survey, which investigated Saudi women’s employment experiences, needs, challenges, and aspirations. The findings identify key legal empowerment strategies that most effectively enhance women’s economic participation. These include continued legal reforms, the promotion of women's education, increased awareness of legal rights and societal responsibilities, and improved access to legal and financial training and support. Additionally, the thesis highlights the importance of promoting personal agency and self-awareness among women to address KSA’s persistent low ranking in global indices for women’s economic participation, despite recent efforts. This study argues that a legal empowerment approach tailored to the socio-cultural context of KSA can meaningfully help overcome persistent barriers and advance gender equality in the economic sphere.5 0Item Restricted A systematic review of different leadership approaches and their impact on the nursing team in emergency(Saudi Digital Library, 2026) Aldawes, Hatem Hadi; Barry, QuinnEmergency departments face demand variation, time pressure, and clinical risk. Leadership shapes nurse well-being, team function, and patient safety. Evidence on emergency nursing leadership remains dispersed across settings. This review synthesised findings within emergency department nursing contexts. This review examined leadership approaches in emergency departments. It assessed effects on nurse well-being, patient care and safety, and team dynamics. It also mapped leadership concepts used across the included studies. A systematic review followed PRISMA guidance. Searches covered PubMed, Scopus, CINAHL, and Web of Science. Studies from 2015 to 2025 met eligibility criteria. Eight studies met the inclusion criteria after screening and full-text review. Designs included five quantitative, two qualitative, and one mixed-methods. Quality appraisal used Joanna Briggs Institute checklists. Thematic analysis followed Braun and Clarke. Four themes emerged across the included studies. Theme one described leadership forms in emergency departments. Clinical leadership appeared as practice-based guidance and coordination. Authentic leadership appeared through transparency, ethics, and balanced processing. Transformational leadership was evident through motivation, support, and a focus on development. Toxic leadership appeared through authoritarian conduct and harmful team effects. Theme two linked leadership with nurse well-being outcomes. Supportive leadership is linked with lower burnout and higher satisfaction. Toxic leadership is linked with stress, burnout, and lower morale. Theme three linked leadership with patient care and safety. Supportive leadership enabled communication, staffing support, and safer care. Toxic leadership is linked to silence, reduced reporting, and increased safety risks. Theme four linked leadership with team dynamics outcomes. Supportive leadership is linked with trust, cohesion, and collaboration. Toxic leadership is linked with conflict, low commitment, and turnover intent. Leadership approaches shape emergency nursing work and care outcomes. Supportive leadership supports nurse well-being, teamwork, and care safety. Toxic 8 leadership harms staff health, teamwork, and safety processes. Further studies should test emergency-specific leadership mechanisms and outcomes.3 0Item Restricted Website Structure Visualisation for Supporting User Navigation(Saudi Digital Library, 2025) Alrebdi, Azzah; Alrebdi, AzzahThis thesis investigates which visualisation techniques support fact-finding tasks through the visualisation of website structures. Large websites, such as university websites, often contain hundreds of thousands of pages organised in hierarchies, which hinder users’ ability to locate specific information. Search engines and navigation menus often fail in such contexts, leading to disorientation and inefficient browsing. The thesis begins with a literature review examining web navigation behaviour, structural complexity, and the role of information scent. Fact-finding tasks were identified as the most appropriate task type for evaluating visualisation techniques. The study then conducted web data collection and processing, including crawling three university websites and constructing region-level hierarchical datasets that formed the basis of all evaluations. Two evaluations were conducted. The first was a technical evaluation of twelve visualisation techniques using three metrics: aspect ratio, visualisation area, and label overlap. Squarified treemap, bubble tree, and tree leaf demonstrated the strongest technical performance and were selected for further investigation. The second evaluation consisted of three user experiments. The first experiment examined performance in identifying known-target regions. Results showed that the squarified treemap and tree leaf outperformed the bubble tree, with performance influenced by region order and number of regions. The second experiment examined explanatory navigation. Results showed that the squarified treemap supported better performance, with effects influenced by information scent and number of clicks. The final experiment focused on the squarified treemap and examined how different encodings and structural metrics affected navigation performance. Results showed that saturation encoding, particularly for outgoing links, led to faster task completion times and fewer errors. The findings provide empirical evidence on how the squarified treemap supports efficient fact-finding tasks in website structures.14 0Item Restricted Consideration of Caregiver Needs and Preferences in the Design and Piloting of an Online Behavioural Caregiver Training Programme for Underserved Regions of Saudi Arabia(Saudi Digital Library, 2025) آل سعود, العنود نواف; Ciara, PaddenConsideration of Caregiver Needs and Preferences in the Design and Piloting of an Online Behavioural Caregiver Training Programme for Underserved Regions of Saudi Arabia20 0Item Restricted High-Gain Isolated DC-DC Converter Topologies for Renewable Energy Microinverter Applications(Saudi Digital Library, 2026) Meshael, Hazem; Elkhateb, AhmadAs electricity demand continues to rise and the transition away from fossil-fuel-based generation accelerates, renewable-energy sources such as photovoltaic panels and fuel cells are being increasingly integrated into modern energy networks. Because these sources inherently provide low output voltage, high step-up DC/DC converters are required to interface them with high-voltage DC buses used in renewable-energy systems, DC microgrids, and electrified transport platforms. In recent converter development, increasing emphasis has been placed on achieving high efficiency, high power density, reduced device stress, and improved practical implementation ability in isolated high-gain conversion stages. However, many existing isolated and non-isolated high step-up converters still rely on extreme duty cycles, large transformer turns ratio, or both, which results in increased semiconductor stress, higher losses, and reduced suitability for practical high-gain operation. This thesis addresses this limitation by proposing and validating a new family of isolated high-gain DC/DC converters: QBFB, CFFB, and CFQFB. The novelty of this work lies in the development of a unified converter family in which a boost-cell stage is integrated on the input side, a voltage-multiplier cell is incorporated on the output side, and an active snubber is employed to clamp switch-voltage spikes and recycle leakage-inductance energy. Through this architecture, very high voltage gain is achieved without extreme duty cycles or large transformer turns ratio, thereby advancing the state of the art toward more practical isolated high-step-up conversion. To validate the analytical findings, comprehensive theoretical, simulation, and experimental investigations were conducted. Closed-form analysis was developed for voltage gain, semiconductor stress, and key operating characteristics, and these results were verified using MATLAB/Simulink and hardware prototypes. Experimental tests were carried out over a range of input voltages, duty cycles, and switching frequencies, including laboratory evaluation at 22 V, 32 V, and 42 V, to characterise efficiency, waveform behaviour, soft-switching performance, and dynamic response.9 0