Saudi Cultural Missions Theses & Dissertations
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Item Restricted Unraveling the magnesium oxide nanoparticles potential for wastewater treatment applications: Atrazine degradation and Legionella disinfection(University of Cincinnati, 2025) Alsaif, Mohammad Yousef A; Wendell, DavidThe growing demand for efficient water treatment technologies, driven by global economic instability and stringent environmental regulations both domestically and internationally, has directed researchers' attention toward nanomaterials, particularly transition metals and their oxides. These materials are renowned for their high efficiency in applications such as the removal of emerging organic contaminants and bacterial disinfection. However, from a practical standpoint, major concerns remain regarding toxicity, cost, and scalability. In this context, magnesium oxide nanoparticles (MgO NPs) have emerged as a promising alternative. MgO is non-toxic, environmentally friendly, cost-effective, and abundant, with notable catalytic and biocidal properties. Nevertheless, its application in water treatment has been limited due to its relatively low efficiency compared to transition metal oxides. The primary objective of this dissertation is to enhance the efficiency of MgO NPs without compromising their inherent advantages. To achieve this, two innovative approaches were implemented: (1) a novel reaction system for the remediation of emerging organic contaminants and (2) a new material synthesis technique tested for antibacterial efficacy. Atrazine (ATZ) was selected as a model organic contaminant to assess the catalytic performance of MgO in activating peroxymonosulfate (PMS) under an underexplored condition, acidic aqueous media. The MgO/PMS system demonstrated remarkable performance, degrading ATZ within minutes. Its efficiency was comparable to the well-established Fenton reaction (using hydrogen peroxide), emphasizing the potential of the MgO/PMS system. This study focused on understanding the degradation mechanism and identifying the major reactive oxygen species (ROS) involved. A scavenger assay confirmed that singlet oxygen (1O2) was the predominant ROS responsible for ATZ degradation. FTIR analysis suggested a complexion-mediated degradation pathway. The degradation intermediates were identified using LC-Q-TOF-MS/MS, and the reaction pathway was proposed. Furthermore, to ensure environmental safety, the toxicity of the ATZ transformation products was evaluated using the U.S. EPA’s Toxicity Estimation Software Tool (T.E.S.T.), which showed a decline in overall toxicity over 120 minutes. This innovative approach repositions MgO as a viable alternative to transition metal oxides for organic contaminant degradation. Simultaneously, a novel synthesis method was developed, microwave- and template-assisted sol-gel synthesis, using varying concentrations of a non-ionic, non-toxic capping agent, Tween 80 (T80). MgO NPs synthesized via this method were compared to those produced by the conventional sol-gel method in terms of structural, morphological, surface atomic configuration, and electronic properties. Only notable differences were observed in the latter two properties. The MgO prepared via the conventional sol-gel method with 6% T80 (MgO-C-6%T80) exhibited the highest antibacterial activity against Escherichia coli and was subsequently tested against Legionella pneumophila, a highly resilient waterborne pathogen. More than a 4-log reduction was achieved within 60 minutes of direct contact. The disinfection mechanism was elucidated based on experimental observations, MgO characterization data, density functional theory (DFT) analysis, and literature support. The results indicated that the primary mechanism involved physical interactions through electrostatic attraction and receptor-ligand interactions with phosphate groups in the bacterial lipopolysaccharide (LPS) layer. This innovative engineering of MgO NPs presents a promising, safe, and affordable strategy for combating even the most resilient waterborne bacteria. This dissertation represents a pioneering effort to revitalize and advance the role of MgO in wastewater treatment, with key contributions including (i) the first in-depth investigation of PMS-activated MgO catalysis under acidic conditions for organic pollutant degradation; (ii) a mechanistic exploration of singlet oxygen generation and its reactivity with heterocyclic organic compounds; (iii) novel insights into the enhancement of antibacterial activity through MgO nanoparticle engineering; and (iv) a detailed study of the MgO biocidal mechanism against Legionella, a bacterium highly resistant to conventional disinfectants. By addressing both technical and ecological challenges in advanced water treatment technologies, this dissertation introduces MgO as a technically viable, economically feasible, and environmentally friendly alternative to transition metals and their oxides.6 0Item Embargo e-HRM in Action: The Relationship Between Employee Behaviours and Perceived Organisational Success – A Comparative Study Between Saudi Arabia and the United Kingdom(University of London, SOAS, 2025) Alabood, Abdulaziz; Reinhard, Bachmann; Senija, CausevicThe new normal, with massive technological advancements, has ushered in a situation where managing employee behaviour has become increasingly challenging. Rapid changes in the workplace have made the matters more complex. With the widespread adoption of technology, particularly the strategic implementation of electronic Human Resource Management (e-HRM), employee behaviours play a crucial role in determining perceived organisational success (POS). The main contribution of this study is the identification of the relationship between e-HRM implementation and POS through specific behavioural constructs: employee engagement (EE), employee empowerment (EEM), organisational citizenship behaviour (OCB), employee performance (EP) and employee agility (EA). This study offers value by providing a theoretical framework for examining these relationships that shape workplace dynamics, drawing on social exchange theory (SET). This quantitative study employs a cross-sectional survey research design to test hypotheses across different organisations and compares findings between the Kingdom of Saudi Arabia (KSA) and United Kingdom (UK). Data were collected from 350 employed respondents from Saudi Arabia and 263 from the UK. IBM SPSS Statistics software was used for coding and analysis, and CB-SEM for Structural Equation Modelling to measure and evaluate the relationships between the study variables. The findings showed that e-HRM implementation related to EEM, which in turn linked to EP, led to POS in the KSA context. Meanwhile, in the UK, e-HRM was linked to OCB, which was subsequently connected to EP and ultimately led to POS. Furthermore, EA did not moderate the relationship between EP and POS in either sample. This study contributes to extending and enriching the literature on e-HRM and employee behaviour, demonstrating how integrating an e-HRM system with employee behaviour enhances the organisation’s ability to foster prosperity.3 0Item Restricted The Impact of AL-Haramain Train Project Service Quality on Saudi Stakeholders Satisfaction(De Montfort University leicster, 2025) jan, Abdullrahim; jin, JingThis research aims to identify the primary factors influencing stakeholder satisfaction with the Al-Haramain Train Project, as it is one of the most significant infrastructure projects contributing to the Kingdom of Saudi Arabia's ambitions under Vision 2030. Furthermore, the study focuses on passenger experiences during peak seasons, such as the Hajj and Umrah, when the demand and expectations linked to this service rise significantly. Based on the SERVQUAL model and Expectation Confirmation Theory (ECT), the research examines the relationships between service quality, expectation confirmation, perceived value, perceived congestion, and overall satisfaction. The study adopts a quantitative approach, based on an online survey of 145 participants. The data was analyzed using partial least squares structural equation modeling (PLS-SEM). The results of this study reveal that service quality has a strong impact on perceived value and expectation confirmation. These two factors were confirmed as being strong predictors of stakeholder satisfaction. Moreover, perceived value and expectation confirmation positively affect stakeholder satisfaction. However, perceived crowding strongly influences the relationship between expectation confirmation and satisfaction but does not significantly influence the relationship between satisfaction and perceived peak, suggesting that users may find good value in a service despite experiencing some degree of environmental discomfort. This study contributes to the current literature by addressing a clear research gap related to passenger satisfaction with public transport in the context of religious tourism. Furthermore, it provides practical recommendations for transport authorities and project managers about how to improve service delivery, manage the challenges that tend to arise during busy seasons, and move forward to meet the goals of Vision 2030.3 0Item Restricted The Pricing of Interest Rate Risk: Evidence from U.S. REITs(University of Nottingmah, 2024-09) Alnasser, Abdulaziz Nasser; Vigier, AdrienThis study examines the pricing of interest-rate risk in U.S. REITs, which have gained increasing interest from investors and academic researchers in recent years. Using a two-factor Arbitrage Pricing Theory (APT) design, this current study was based on data collected over five years, including total returns for U.S. equity REITs, interest rate changes, and returns for relevant market indexes. Empirical results indicate that REITs are significantly negatively sensitive to interest rate fluctuations, which suggests that for investors, there should be a premium compensation against such risk. This paper stipulates the interest rate effect as an important factor that investors and policymakers cannot afford to neglect when making decisions and formulating their investment strategies.2 0Item Restricted أثر الاستثمارات الخارجية على الاقتصاد المحلي: دراسة تحليلية مع التطبيق على صندوق الاستثمارات السعودي(جامعة المنصورة – جمهورية مصر العربية, 2024) الظفيري, فلاح; عبد الرؤوف, إبراهيمهدفت هذه الدراسة إلى تقييم أثر الاستثمارات الأجنبية على النمو الاقتصادي وتطوير سوق الأوراق المالية وتوليد فرص العمل داخل المملكة العربية السعودية. أظهرت النتائج وجود علاقة ذات دلالة إحصائية بين حجم الاستثمار الأجنبي المباشر ومعدل نمو الناتج المحلي الإجمالي، إضافةً إلى دور الاستثمارات الأجنبية في تعزيز سيولة وأداء سوق الأسهم. كما أكد التحليل أن تأسيس الشركات الأجنبية أسهم بوضوح في توفير وظائف للعمالة الوطنية وتقليل البطالة. وانتهت الرسالة إلى مجموعة توصيات لتعظيم الآثار الإيجابية لتدفقات رؤوس الأموال الأجنبية وتحسين البيئة التشريعية لتعزيز جاذبية الاستثمار.0 0Item Restricted CACHING TECHNIQUES FOR REDUCING THE COMMUNICATION COST OF FEDERATED LEARNING IN IOT ENVIRONMENTS(University of Missouri - Columbia, 2025) Alhonainy, Ahmad; Rao, PraveenFederated Learning (FL) introduces a new way to use data for machine learning, emphasizing privacy by handling data locally at the network’s edge, instead of large, centralized servers. This thesis aims to improve FL on the Internet of Things (IoT) settings by developing and applying sophisticated caching methods. These methods are intended to lower the communication demands that come with regularly updating the model between the network's edge devices and the server. High communication costs can limit the use of FL, especially in situations involving many IoT devices with restricted bandwidth and limited power. The primary objective of this research is to apply caching strategies that can decrease how often data is sent during the learning process. This involves investigating caching techniques to send only the most crucial model updates, thus cutting down on unnecessary network traffic and boosting the efficiency of the system. The study also looks at how these strategies affect the performance and precision of the learning models, making sure that reducing communication does not harm the quality of the machine learning results. Furthermore, this thesis looks at the wider effects of better communication efficiency in FL for IoT. By lowering the strain on network resources, more devices can take part in the learning process. This could increase the variety and amount of data that helps train the models without risking user privacy. This is especially crucial in areas like healthcare where processing data locally and only sharing vital information can greatly increase user trust and the adoption of the system. Through detailed experiments and assessments, this research seeks to develop a set of guidelines and recommendations for using caching in FL setups. The findings are expected to offer valuable insights into how FL can be made more scalable, efficient, and effective in IoT settings, helping to expand its use in both the commercial sector and academic studies.9 0Item Restricted THE MULTIFACETED ROLE OF ANGIOTENSIN II IN SKELETAL MUSCLE AUTOPHAGY SUPPRESSION IN HEART FAILURE(Tulane university, 2025) Sindi, Fareed; Yoshida,TadashiChronic skeletal muscle (SKM) atrophy, or cachexia, occurs in diseases such as congestive heart failure (CHF), and are often associated with high levels of angiotensin II (ANG-II). We have shown that ANG-II infusion reproduces major aspects of CHF-induced SKM atrophy and causes mitochondrial damage and dysfunction in SKM. ANG-II also inhibits autophagy, and a combination of these effects likely causes accumulation of damaged mitochondria, leading to SKM atrophy. However, the precise molecular mechanisms whereby ANG-II inhibits autophagy are unknown. We hypothesize that ANG-II infusion suppresses autophagy in SKM via activation of mTOR and inhibition of FOXO3a. To test this hypothesis, we infused ANG-II into twelve-week-old FVB mice via osmotic minipumps for 7 days. Expression of autophagic markers and FOXO3a target genes were analyzed in SKM by western blotting and RT-qPCR, respectively. Colchicine and 24-hours STR treatment were included to assess autophagic flux in vivo. We found that in the presence of colchicine, LC3B lipidation was decreased in the ANG-II group, indicating that ANG-II inhibits autophagy at the APS formation step. Furthermore, ANG-II increased p62 and PINK1 and decreased BNIP3, suggesting that ANG-II-mediated reduction of autophagy causes disruption of the normal process of damaged mitochondrial clearance via mitophagy. To quantify the number and size of the APS and ALS were quantified in SKM frozen sections with a combination of fluorescent imaging and machine-leaning based image segmentation. We observed reduced number of APS and ALS in ANG-II group compared to control, suggesting that ANG-II suppresses APS and ALS formation. Mechanistically, ANG-II likely inhibits APS and ALS formation via mTOR and FOXO3a pathways: our data indicate that ANG-II increased mTOR phosphorylation (i.e. mTOR activation) and its downstream targets. ANG-II increased FOXO3a phosphorylation (i.e. FOXO3a inhibition), which was associated with reduced mRNA expression of FOXO3a target genes, such as LC3B and BNIP3. In summary, our study suggests that ANG-II-mediated activation of mTOR and inhibition of FoxO3a leads to suppression of APS and ALS formation in SKM. It is suggested that suppression of autophagy via these pathways likely disrupts clearance of damaged mitochondria, leading to SKM atrophy. These results provide the rationale for future development of therapies to treat CHF-induced cachexia via targeting the mTOR-FOXO3a axis to restore normal levels of autophagy.10 0Item Restricted English Representations of Muslim Characters in the Drama of the Renaissance(University of Tennessee-Knoxville, 2025) Alshammari, Adel Sahan; Hirschfeld, HeatherThis dissertation explores how Muslim characters are portrayed in English literature from the medieval to the Renaissance period, focusing on early modern drama. It traces the shift from the stereotypical Saracen villain in crusading literature to the more complex figures of the Turk and the Moor. The study explores how English playwrights used these characters to express anxieties and address questions of identity, empire, and religious difference. Focusing on Christopher Marlowe’s Tamburlaine the Great and William Shakespeare’s Othello, this research argues that Renaissance drama moves beyond the simple negative depictions of Muslims found in earlier works, offering more nuanced and complex portrayals that still reflect ideological tensions. These plays use storytelling to engage with power, race, religion, and cultural difference. Drawing on historical context, theology, and recent scholarship in medieval and early modern studies, this study shows how Muslim characters act as both reflections and contrasts to English concerns about power, morality, and cultural identity.9 0Item Restricted The role of financial performance analysis in strategic planning in healthcare evidence from king faisal specialist hospital and research(Brunel University, 2025) Abdallah, Laila; Shaukat, AmamaThis dissertation explores the role of financial performance analysis in strategic planning within the healthcare sector, focusing on King Faisal Specialist Hospital and Research Centre. Using a quantitative research approach, it examines how financial literacy, leadership competency, and key performance indicators influence decision-making, resource allocation, and operational efficiency. The study identifies challenges in data accessibility and utilization and highlights the importance of integrating financial insights into healthcare strategy. Findings support the need for enhanced financial education and technology adoption to strengthen planning processes and improve long-term sustainability, organizational resilience, and patient care outcomes.10 0Item Restricted Understanding Telemedicine Communication Through Critical Incidents: A Grounded Theory Investigation of Patients’ Experiences(George Mason University, 2025) Alghamdi, Amjad Abdulaziz; Wright, KevinThe rapid expansion of telemedicine during the COVID-19 pandemic has transformed patient-provider communication, particularly in mental health and chronic care contexts. Yet, limited research has examined patients' nuanced perceptions of communication quality in telehealth settings from the lens of lived experiences. This dissertation investigates how patients evaluate provider communication in telemedicine by analyzing naturally occurring narratives shared on Reddit. Using a constructivist grounded theory approach, informed by the Critical Incident Technique (CIT), the study explores 84 critical incidents across 39 Reddit threads to identify how communication behaviors shape patients’ experiences of virtual care. Guided by three theoretical frameworks Patient-Centered Communication (PCCm), Social Presence Theory (SPT), and Media Affordance Theory (MAT) the analysis revealed 17 interrelated themes spanning relational behaviors (e.g., empathy, attentiveness), emotional presence (e.g., immediacy, affective expression), technological features (e.g., interactivity, anonymity), and contextual constraints (e.g., environmental disruptions, financial access). These themes reflect a multidimensional communication in which satisfaction depends not only on clinical outcomes but on the alignment between patient needs, provider engagement, and platform capabilities. Findings demonstrate that virtual care succeeds when communication is emotionally attuned, responsive, and structurally supported. At the same time, the study reveals theoretical tensions such as when provider empathy is insufficient to overcome technical or contextual barriers thereby extending existing models of telehealth communication. This research highlights how users make sense of care in emotionally charged digitally mediated contexts. In addition to advancing theory, the study offers concrete implications for healthcare providers, platform designers, and educators seeking to improve communication quality, emotional safety, and equity in virtual care delivery. The use of Reddit as a naturalistic data source also illustrates the potential of social media in capturing patient perspectives often missed in traditional research. This dissertation contributes to the growing body of research at the intersection of digital health communication and computer-mediated care by theorizing how social presence and media richness shape patient satisfaction in telehealth environments. It further demonstrates the value of Reddit as a data source for understanding patient voices in naturalistic, emotionally charged contexts. Implications are offered for health communication scholars, educators, and practitioners seeking to enhance relational quality and trust-building in virtual care delivery.11 0