SACM - United States of America
Permanent URI for this collectionhttps://drepo.sdl.edu.sa/handle/20.500.14154/9668
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Item Restricted Formulation and Characterization of Biopolymer for Solid-State Electrolytes(Saudi Digital Library, 2026) Alzahrani, Turki; Aravamudhan, Shyam; Rathnayake, HemaliFlammable organic electrolytes and narrow oxidative stability still prevent next-generation solid state lithium-ion batteries from using high-voltage cathodes with sustainable polymers. This dissertation addresses this problem by developing a bio-sourced, chitosan-based solid polymer electrolyte reinforced with a tannic-acid–lithium metal–organic framework (TALi). The TALi is novel because it combines phenolic anchoring sites from tannic acid with lithium coordination, creating both Li⁺ binding sites and mesoscale porosity in a single additive. Casting 4:1 chitosan:TALi films followed by controlled protonation produces dense 120 µm membranes with room-temperature ionic conductivity of 4.38 × 10⁻⁴ S cm⁻¹ about 12 times higher than pure chitosan. Conductivity increases to 1.90 × 10⁻³ S cm⁻¹ at 80 °C with an activation energy of 0.252 eV. Linear-sweep voltammetry shows practical stability up to ≈ 4.9 V vs Li/Li⁺ at 0.10 mA cm⁻². Li ‖ 4:1 film ‖ NMC 532 coin cells deliver 127 mAh g⁻¹ at C/20 (85% of liquid-electrolyte capacity) and retain 109 mAh g⁻¹ after 34 cycles with 93–95% coulombic efficiency, giving a fade rate of 0.06% per cycle. Rate tests show 56.8 mAh g⁻¹ at C/5 and 98% capacity recovery when returned to C/20. Spectroscopic and dielectric analyses show the high conductivity comes from dual Li⁺ transport pathways. These include segmental motion along protonated chitosan chains and vacancy-assisted hopping across catecholate sites in the MOF. Maxwell–Wagner polarization inside 50–200 nm pores also increases free-ion density. A percolation optimum near 20 wt% TALi balances conductivity, mechanical properties, and electrochemical window. This work demonstrates a practical approach toward safer, high-voltage, bio-derived electrolytes using scalable solution processing methods10 0Item Restricted “Developing a Strong and Durable Universal Self-Etching Adhesive Resin Agent.”(Saudi Digital Library, 2025-05-23) Alomran, Waad; Sun, Jirun; Sun, JirunConventional methacrylate-based dental adhesives are prone to hydrolytic and enzymatic degradation, limiting their durability and long-term clinical success. This study introduces two novel self-etching universal adhesive formulations that replace hydrolytically unstable monomers with ether-based alternatives—TEGDVBE combined with either UDMA or PMGDM—alongside the functional monomer 10-MDP, known for its strong chemical affinity to dentin. These formulations were evaluated against an experimental Bis-GMA/HEMA/10MDP control and a commercial benchmark, Scotchbond Universal. Adhesive performance was assessed across key parameters: water contact angle, resin spreading kinetics, degree of conversion, flexural properties, and both shear and microtensile bond strengths. The TEGDVBE-based adhesives demonstrated greater hydrophobicity and enhanced resistance to moisture-induced degradation, while maintaining efficient polymerization. Both experimental formulations achieved bond strengths on par with or superior to the controls, and exhibited mechanical properties within clinically acceptable ranges. These results support ether-based monomers as a viable, biocompatible alternative to traditional methacrylate systems. By improving hydrolytic stability without compromising adhesion or mechanical performance, these formulations represent a promising direction for next-generation dental adhesives. Further, in vivo studies are warranted to validate their long-term clinical performance.9 0Item Restricted Investigating IoT Adoption in the Face of Organizational Culture and Uncertainty Challenges: The Mediating Role of Information Behaviors on Communication Quality(Saudi Digital Library, 2025-05-17) ALASMARI, AHMAD; Shabtai, ItamarAbstract Investigating IoT Adoption in the Face of Organizational Culture and Uncertainty Challenges: The Mediating Role of Information Behaviors on Communication Quality By Ahmad Ali Alasmari Claremont Graduate University: 2025 The successful integration of Internet of Things (IoT) technologies in higher education institutions necessitates agile service deployment, transparent communication, and cultural congruence. Guided by Social Cognitive Theory (SCT) and Diffusion of Innovation (DOI) frameworks, this mixed-methods study examines the interconnections between High Uncertainty Avoidance, Organizational Culture, Information Availability, Information-Seeking Behavior, and IoT Service Agility and their collective impact on Communication Quality at the University of Tabuk in Saudi Arabia. Employing a sequential explanatory design, quantitative data from 373 survey respondents was augmented by qualitative insights from seven in-depth interviews with faculty, administrative staff, and IT management. Findings demonstrate that high uncertainty avoidance significantly diminishes IoT agility and adversely affects communication quality, while a supportive organizational culture enhances communication effectiveness. The relationships among cultural characteristics, IoT agility, and communication quality are mediated by proactive information behaviors, specifically information seeking and availability. The study provides practical strategies to overcome cultural and uncertainty-related barriers, including enhancing information transparency, implementing structured training programs, and fostering proactive leadership engagement. These insights offer valuable guidance for Saudi Arabian higher education institutions and similar contexts aiming to optimize IoT technology adoption.1 0Item Restricted تعزيز القيادة التربوية من خلال التدريب الفعال وتطوير التعلم مدى الحياة في المدارس الابتدائية في المملكة العربية السعودية(Saint Louis university, 2025) الحربي, عائشة; wood, joLifelong learning is the process of acquiring continuous knowledge and skills that enable educators to keep abreast with certain changes in the field of education throughout their profession. In the current educational landscape, creating a lifelong culture has become vital for schools' effectiveness and the professional development of staff. This study uses a descriptive qualitative research method to uncover how school leaders perceive their training in supporting teachers with instructional practices, technology integration, and collaboration to promote lifelong learning. This approach was chosen since it allows an in- depth examination of participants' experiences. The researcher conducted semi- structured interviews with thirteen principals at elementary schools in Saudi Arabia. Data was interpreted thematically, where the interview recordings were transcribed, and open coding was used to capture key themes related to research questions. Data was then triangulated to identify diverging and converging themes. The first major theme showed that there was inadequacy and variability in training. Many of the principals were highly dissatisfied with the formal training offered by the government and described it as repetitive or lacking practical relevance. The second theme demonstrated leadership support as a driver for positive school culture, where strong leadership support, particularly emotional and motivational, was a crucial factor in driving positive school culture. The third theme emphasized the role of collaboration and shared vision as foundational strategies for improving school climate. The study findings also showed that Professional Learning Communities (PLCs) were widely adopted as tools for change to foster collaboration, reflective practice, and continuous improvement. The fifth theme highlighted the positive role of motivation and recognition as behavior-shifting tools for influencing the teacher's behaviors and encouraging innovation. Another major theme was teacher behavioral and instructional change post-professional development, where many leaders observed significant changes in teacher behavior following targeted professional development. The first minor theme highlighted the importance of emotional and motivational support as a leadership tool. The second minor theme focused on barriers to implementation where there is a lack of resources and financial Support. The final theme was resistance to change, with initial resistance to professional development or new strategies, especially among veteran teachers10 0Item Restricted LIFESTYLE RISK ASSESSMENT SCORE FOR PERIODONTAL DISEASE (LRASPD)(Saudi Digital Library, 2026) Almijlad, Asma; Andre Paes Batista da Silva, DDS, MSc, Ph.D.; Suchitra Nelson, Ph.D.; Jeffrey Albert, Ph.D.; Johnie Rose, MD, Ph.D.Background: Periodontitis is a chronic inflammatory disease that destroys tooth-supporting tissues (gums, ligaments, and bone). It is a multifactorial disease that is impacted by behavioral, genetic, environmental, and immunological factors. However, the main etiology is poor oral hygiene, which causes the accumulation of dental plaque. There are limited studies on the association between a combination of lifestyle factors and periodontal disease, nor is there a comprehensive risk assessment score that can be used clinically. The aim of the study is to investigate the association of socio-demographic variables and lifestyle factors with periodontitis, and to create a Lifestyle Risk Assessment Score for Periodontal Disease (LRASPD) to be used as a screener in the dental clinic. In addition, the association of LRASPD with periodontitis was examined. A secondary analysis was performed to assess if diabetes status alters the association of LRASPD with periodontitis. Methods: A cross-sectional study using secondary data from the National Health and Nutrition Examination Survey (NHANES) from the 2009-2010, 2011-2012, and 2013-2014 cycles was conducted. Adults aged 30 years and above with complete data on 2 periodontitis, lifestyle, and demographic factors were selected. Bivariate and multiple logistic regression were used to analyze the data. Also, LRASPD was created by converting coefficients from the logistic regression to a score based on the following demographic (age, gender, race/ethnicity, education level, and poverty income ratio) and lifestyle (smoking, alcohol consumption) variables. Results: The final logistic regression with only significant variables showed that current and past smokers had 2.41 and 1.31 higher odds of moderate/severe periodontitis than non-smokers; while heavy and moderate drinkers had 1.60 and 1.04 higher odds, respectively, than no/light drinkers. Individuals aged 45-64 had 3.48 times higher odds, and those aged 65 and older have 4.08 times higher odds compared to those aged 30-44. Males had 2.21 times more moderate/severe periodontitis than females. Other races had 1.74 higher odds, non-Hispanic Blacks 1.40, and Hispanics 1.34 higher odds than non-Hispanic White individuals. Those with less than a high school education had 1.45 times higher odds compared to those with higher education. Individuals below the poverty level had 1.26 times higher odds compared to those at or above the poverty level. Individuals with a high-risk score of the LRASPD had 15.13 increased odds of having moderate/severe periodontitis compared to those with no/low-risk scores. After adjusting for diabetes, individuals with a high-risk score of the LRASPD had 14.78 increased odds of having moderate/severe periodontitis compared to individuals with a no/low-risk score. Individuals with diabetes had 1.23 increased odds of having moderate/severe periodontitis. 3 Conclusion: Individuals with a high-risk score of LRASPD, followed by individuals with moderate-risk, had higher odds of having moderate/severe periodontitis compared to individuals with a low-risk score, which indicates a potential dose-dependent relationship. Also, diabetes has lower odds of having moderate or severe periodontitis compared to the LRASPD groups, which suggests that LRASPD plays a more significant role than diabetes. The LRASPD may serve to evaluate lifestyle risks of periodontal disease in dental clinic settings. Also, it can help to understand the combined impact of lifestyle factors on the development and progression of periodontal disease.18 0Item Restricted Cross Dataset Fairness Evaluation of Transformer Based Sentiment Models(Saudi Digital Library, 2025-05-10) Zuiran, Sara; Bhattacharyya, SiddharthaWith the growing exploration of Natural Language Processing (NLP) systems in decision-making environments, it is essential to evaluate technical and ethical aspects of the dataset and the NLP model to improve fairness. To assess fairness, the thesis examines demographic imbalances in sentiment classification models by evaluating transformer-based models fine-tuned on the Stanford Sentiment Treebank version 2 dataset (SST-2) against the demographically annotated Comprehensive Assessment of Language Model dataset (CALM). This work identifies performance disparities in sentiment prediction across demographic groups by examining sensitive attributes such as gender and race. The study evaluates both the RoBERTa and MentalBERT transformer models using a complete set of fairness metrics consisting of Statistical Parity Difference (SPD), Equal Opportunity Difference (EOD), False Positive Rates (FPR), False Negative Rates (FNR), Jensen-Shannon Divergence (JSD), and Wasserstein Distance (WD). The analysis examines both group-vs-rest and pairwise subgroup comparisons, including gender and ethnicity. Results show that applying adversarial mitigation reduced fairness disparities across demographic subgroups, with the most notable improvements observed for non-binary and Asian users. The observed disparities emphasize the challenge of reducing performance gaps across demographic subgroups in sentiment classification tasks. The thesis introduces a practical framework for evaluating demographic dis- disparities, extends fairness analysis, and assesses the impact of mitigation techniques in cross-dataset sentiment classification. This research proposes a framework that demonstrates a path toward creating inclusive NLP systems and establishes the groundwork for upcoming ethical Artificial Intelligence (AI) studies.13 0Item Restricted The Impact of Augmented Reality-Based-Affordances Instruction on Learners’ Motivation in K-16 Classrooms: An Integrative Review(Saudi Digital Library, 2025-05-13) Aljohani, Amal Hamdan; Peter DoolittleAugmented Reality (AR) is a rapidly growing technology used in education to improve traditional learning by adding digital content to the real world. This literature review explains what AR is and how it differs from similar technologies like Virtual Reality (VR), Mixed Reality (MR), and Diminished Reality (DR). Using instructional design frameworks, it highlights AR's special features, such as interactivity, visual learning, and immediate feedback that encourage active learning and match motivational theories, especially self-determination theory. The review gathers findings from various educational fields, including primary schools, medical training, and engineering, showing that AR positively affects student learning and motivation. It also looks at how AR is used in online and distance learning, emphasizing its ability to provide realistic, hands-on experiences remotely. The review stresses the importance of rigorous research methods and reliable sources, offering a clear foundation for understanding AR’s potential in education and suggesting areas for future research and practice.19 0Item Restricted PERSON-CENTERED KIDNEY CARE AND TRANSITION TO DIALYSIS: AN INVESTIGATION FROM SAUDI ARABIA(Saudi Digital Library, 2027-01-01) Alfahad, Abdulrahman Abdulmuslih S; Toles, Mark P; Almutary, Hayfa; Crandell, Jami; Ya-Ke “Grace” Wu; LeBlanc, MathewThis dissertation examines Person-Centered Care (PCC) in patients with Advanced chronic kidney disease (CKD) on dialysis in Saudi Arabia. It aims to advance PCC research and inform practical applications through five main objectives: (a) characterize Patient-Reported Outcomes (PROs) in CKD; (b) describe patient engagement among adult non-dialysis CKD patients; (c) identify population characteristics, including emotional and informational support, associated with patient engagement; (d) examine the relationship between patient engagement and health-related outcomes; and (e) characterize patient experiences during the transition to dialysis and identify factors that facilitate unplanned dialysis initiation. Chapter 2 findings of a scoping review of studies conducted in Saudi Arabia, which identified literature gaps, particularly in the standardized measurement of PROs, non-individual or environmental factors relate to patient-reported outcomes, and the underrepresentation of non-dialysis CKD patients in research. Chapter 3 reports the findings of a cross-sectional study of 128 patients which found that most participants scored the lowest engagement level. Key predictors of low engagement were low education level, low emotional and informational support. Chapter 4 reports findings from a qualitative study exploring the reasons that patients often initiate dialysis under emergency or unplanned circumstances. Through in-depth interviews with 18 patients who experienced unplanned dialysis initiation, findings characterize a range of individual, social, and healthcare system factors that contributed to unplanned dialysis initiation. The findings from this dissertation identifies actionable strategies to enhance person-centered and value-based care. The studies collectively highlight the urgent need for improved pre-dialysis care, including earlier nephrology care, integration of multidisciplinary teams, and proactive engagement of patients. Future research should prioritize designing and evaluating structured pre-dialysis programs that promote timely planning and smooth transitions to dialysis, incorporating elements such as patient education, self-management support, and activation strategies. At the policy and practice level, embedding routine PRO measurement, strengthening patient-provider communication, and tailoring care to patients’ social and emotional needs are essential to optimizing CKD care and aligning it with Saudi Arabia’s Vision 2030 healthcare transformation.7 0Item Restricted Temporal Splitting Schemes for Multiscale Problems(Saudi Digital Library, 2027-08-09) Alshahrani, Mohsen Ghanem Abdullah; Efendiev, YalchinMany real-life problems have a multiscale nature and high contrast coefficients. High contrast is known to pose significant challenges in numerical simulation, especially for time-dependent problems. Implicit methods are commonly used for time discretization; although they are unconditionally stable, they require expensive computations at each time step. In contrast, explicit methods are computationally efficient per time step but require very small time steps to maintain stability, due to the mesh size and contrast. We propose temporal splitting algorithms for multiscale problems in mixed form that balance the efficiency of explicit methods with the stability of implicit methods. This approach is applied to flow, wave, and quasi-gas-dynamic (QGD) problems. We decompose the pressure space into two components: a coarse-grid part and a correction part. Each is paired with a corresponding velocity space, namely a coarse-grid velocity space and a correction velocity space. The coarse-grid subspaces are designed to capture fast-scale features influenced by high-contrast variations, while the correction subspaces account for slow-scale features that are independent of contrast and not resolved by the coarse-grid approximation. Using this decomposition, we develop temporal splitting schemes that treat fast components implicitly and slow components explicitly. The stability of the proposed algorithms is ensured through a careful design of multiscale spaces. We also show that time stepping in the correction spaces is independent of contrast. Additionally, we find that the allowable time step scales with the coarse mesh size, which can lead to significant computational savings. We further propose multicontinuum splitting schemes for the wave equation and the quasi-gas-dynamic problem with high-contrast coefficients. To separate fast and slow dynamics in the system, we decompose the solution space into two components. This is achieved by introducing physically meaningful macroscopic variables and employing the expansion in multicontinuum homogenization. Based on this decomposition, we formulate partially explicit time discretization schemes in which the fast (contrast-dependent) component is treated implicitly to ensure stability, while the slow (contrast-independent) component is treated explicitly to enhance computational efficiency. We introduce the concept of discrete energy and derive corresponding stability conditions, which remain independent of contrast when the continua are properly chosen. In addition, we discuss strategies for optimizing the space decomposition. Numerical examples are presented to validate the accuracy and stability of the proposed schemes.51 0Item Open Access UNDERSTANDING REPEAT USE AND WORD-OF-MOUTH IN RESTAURANT RESERVATION APPS: AN INTEGRATED UTAUT2 AND USES & GRATIFICATIONS APPROACH(Saudi Digital Library, 2025-07-16) Alhaidar, Maher; Joung, DavidThis study explores the technological and psychological factors influencing users’ repeat use and word-of-mouth (WOM) behavior regarding restaurant reservation apps in Saudi Arabia. By integrating the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2) with the Uses and Gratifications (U&G) Theory, the research develops a comprehensive framework to assess how constructs such as performance expectancy, effort expectancy, hedonic motivation, price-saving orientation, societal pressure, and various gratification types shape e-satisfaction and usage intention. A cross-sectional survey of 485 Saudi app users was conducted, and the data were analyzed using confirmatory factor analysis (CFA) and structural equation modeling (SEM). The findings indicate that both technological and gratification-driven constructs significantly impact e-satisfaction and usage intention, which, in turn, positively influence repeat use intention and WOM behavior. This study advances hospitality and technology adoption literature by offering a context-specific model that bridges functional, emotional, and social motivations. Practically, it offers valuable insights for app developers, marketers, and hospitality professionals aiming to enhance user experience, drive retention, and foster digital engagement.23 0