SACM - United States of America
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Item Restricted Towards Legal Reform of the Enforcement of Directors' Duties in the Context of Shareholders' Rights Protection.(Saudi Digital Library, 2025-05-16) Alotaibi, Ayman; STEVEN D ROSEN, ESQUIRECorporate Governance, Directors' Duties, and Shareholders' Rights Protection Legal Landscape of Directors’ Duties in Saudi Arabia Legal Landscape of Directors’ Duties in the USA5 0Item Restricted Exploring Al Balad(Saudi Digital Library, 2025-05-23) alqunfuzi, danah; Mitchell, JacobAl Balad is a well-known destination for Jeddah’s visitors. With its inclusion in UNESCO World Heritage, the site has been transforming to fit the standards and become a more tourist destination. The reason the site is included in UNESCO is due to its diversity and unique architecture and sense of place. Preservation of this type is problematic because it threatens to suppress the dynamics that gave rise to Al Balad, freezing it in time. This thesis asks: How can landscape representation capture agents of change, the present moment, and the past so that the forces that breathe life in historically preserved areas are identified and these sites don’t lose their sense of place?3 0Item Restricted Evaluation of Resveratrol and BioDendrimer-Resveratrol in Models of Dental Pulp Inflammation – In-vitro(Saudi Digital Library, 2025-05-30) Alzahrani, Lina; Gibbs, JenniferVital pulp therapy (VPT) aims to preserve dental pulp tissues and maintain tooth function, while alleviating dental pain. However, persistent pain may necessitate more invasive treatments like root canal therapy (RCT). Current clinical VPT protocols lack options for treatments that might enhance tissue healing and improve post-operative pain outcomes. Resveratrol (RESV), a naturally occurring bioactive compounds, that exists in 72 plant species such as grapevines, blueberries, and others. RESV is known for its anti-inflammatory, antimicrobial, and neuroprotective effects, and it holds promise for VPT. Our aim is to determine the effects of two formulations of resveratrol (resveratrol (RESV) and biodendrimer- resveratrol (BD- RESV) on cytokine expression, mineralization and migration of dental pulp stem cells (DPSCs) challenged with LPS as an in-vitro model of pulpitis. Commercially available (Lansa) DPSCs from healthy adult teeth were grown using a-Minimum Essential Medium (Sigma-Aldrich, St Louis, MO) supplemented with other agents. Cells were maintained at 37 °C / 5% CO2 and plated for experiments at passage 2 or 3. Cells were treated for 2 to 7 days with varying doses of RESV (0.001-100μM), BD-RESV (0.001-100μM) and challenged with LPS or vehicle control (0.001-100μg/ml). Cell viability was assessed using the MTT assay on day 7, cell migration and cytokine expression (qRT-PCR) were evaluated on day 2 and mineralization was evaluated with alizarin red staining on day 28. We found that BD-RESV decreased LPS -induced DPSC cytotoxicity with statistically significant effect on LPS dose of 1μg/ml (p< 0.05), while RESV had no effect. However, both RESV and BD-RESV significantly prevented LPS induced upregulation of IL1-β, IL-6, IL-8 mRNA (p< 0.05). RESV and BD-RESV also induced the formation of calcium nodules (alizarin Staining) with the most significant effect observed at RESV 5μM and BD-10 μM (p< 0.05) and significantly increased DPSC migration (p< 0.05). Resv and Biodendrimer demonstrated a similar ability to mitigate LPS-induced cytokine upregulation and induce mineralization and DPSC migration suggesting its properties are particularly relevant to improve tissue healing in dental pulpas an inflammatory response modulator. However, further in-vivo research that incorporates RESV and BD-RESV as a direct pulp capping material in pulp exposure model of pulpitis is necessary to confirm that RESV's would be useful as a VPT supplementary component.9 0Item Restricted The Influence of Climate Concerns, Fintech, and Policy Uncertainty on Green and Carbon-Based Investments in Islamic and Conventional Finance(Saudi Digital Library, 2025-05-14) Altamimi, Hissah; Hassan, Mohammad KAbstract Integrating green finance, monetary and fiscal policy, and environmental, social, and governance (ESG) is an important yet unexplored area of research in the risk management strategies of banks in emerging economies. This study ventures into an exploratory examination of this association, situated in the socio-cultural milieu of Asian countries. In this region, the lower implementation of technology and governance quality leads to a bias towards short-term perspectives. Drawing on the role of agency and stakeholder theory, the study aims to investigate the moderating role of the Fintech Technology Index in green finance, fiscal and monetary policy on ESG performance. The sample includes 296 banks (52 Islamic, 244 conventional) with 2970 observations from 22 Asian countries during 2013–2022. The study further explores the role of green finance and monetary policy towards ESG, which are very positive, illustrating the more substantial effect of the FinTech technology index across Islamic and conventional banks. Notably, the study found that the impact of technology indicators on ESG performance is more influenced in Islamic banks, where the role of fiscal policy is more aligned with the conventional banks of Asian economies. Policymakers and leaders should, therefore, establish regulations that encourage technology-based initiatives and governance that promote sustainable activities, minimizing ESG issues, as suggested by additional analysis of ESG performance along with individual pillars. JEL Classifications: G14, G34, H26 Keywords: Green Finance: Fiscal and Monetary Policy: ESG performance: FinTech Technology: Stakeholder theory.20 0Item Restricted Cluster Modified Nanopore for Protein Post-Translational Modification Detection(Saudi Digital Library, 2025-05) Almahyawi, Mohammed Hussain A; Reiner, JosephThe precise and sensitive detection of protein post-translational modifications (PTMs), particularly phosphorylation, is critical for advancing our understanding of cellular signaling and disease pathology. In this thesis, we present a nanopore-based biosensing platform enhanced by cluster modifications, offering novel capabilities for the single-molecule analysis of phosphorylated peptides. Nanopore-based biosensors have emerged as a powerful single molecule platform due to their label-free detection, high temporal resolution, and ability to directly probe the physical properties of biomolecules. The introductory chapter outlines the principles of nanopore sensing and its relevance as a next generation biosensing technology. The second chapter explores the use of nanoparticle-assisted nanopores for detecting ovarian cancer peptide biomarkers, demonstrating the method’s capability to discriminate between cysteine-containing peptide variants from clinically important proteins such as LRG-1. Building on this, the third chapter presents a detailed study on the discrimination of isomeric phosphorylated peptides derived from the human insulin receptor. A cluster-modified nanopore platform enabled accurate identification of phosphorylation states at the single-molecule level. To enhance the classification of nanopore signals, a Gaussian Mixture Model (GMM)-based machine learning pipeline was developed and optimized specifically for the complex signal profiles produced by the cluster-modified nanopore. The fourth chapter is dedicated to the design and optimization of the GMM algorithm, tailored to capture the multi-modal characteristics of the nanopore signal distributions. The final chapter examines the interaction of titanium dioxide (TiO₂) nanoparticles with phosphonate ligands in the nanopore environment, offering insight into the chemical challenges and opportunities in designing phosphonate-specific sensing platforms. Altogether, this work establishes an integrated strategy for high precision phosphoproteomic sensing using modified nanopores and machine learning, demonstrating the potential of this technology for both research and clinical diagnostics.16 0Item Restricted Exploring Evolutionary History and Climate Adaptation in a Freeze-tolerant VertebrateSkelly, David(Saudi Digital Library, 2025-05) Alshwairikh, Yara; Skelly, DavidAs we consider the future of species in a changing climate, it is critical that evolutionary perspectives become part of the grounding for conservation planning. Responses to changing climate will undoubtedly vary among species, and for ectotherms, temperature plays a crucial part in many aspects of their biology such as reproduction, growth, and overwintering. Adaptation may be critical for species surviving the effects of climate change, and understanding the evolutionary history for species is an essential baseline for uncovering their adaptive potential and predicting their evolutionary trajectory. My research focuses on the wood frog (Rana sylvatica=Lithobates sylvaticus) – a cold adapted, freeze-tolerant amphibian that is simultaneously the most widely distributed amphibian in North America, and highly vulnerable to human modifications to its environment. In this dissertation, I disentangle how lineage diversification within wood frogs proceeded following the Last Glacial Maximum (LGM). I investigate how wood frog genomes adapted to environmental conditions experienced over a 32-year period and identify regions of the genome as candidates for environmental adaptation. Lastly, I perform a freeze-thaw experiment to uncover the gene-expression profile of the complex and quick freeze-thaw process, and identify candidate genes for their role in freeze- tolerance adaptation.10 0Item Restricted CO₂ RESPONSIVE NANOPARTICLES FOR ENVIRONMENTAL AND INDUSTRIAL APPLICATIONS(Saudi Digital Library, 2025-05) Khdary, Duaa; Giannelis, EmmanuelThis thesis investigates the interfacial behavior, colloidal stability, foam stabilization capacity, and CO₂ uptake of CO₂-responsive silica nanoparticles, synthesized via surface functionalization with single and dual silane chemistries. The surface modification was carried out using N1-(3-trimethoxysilylpropyl) diethylenetriamine and N,N-diethylaminopropyl trimethoxysilane to impart CO₂-responsiveness and tunable surface properties. Comprehensive characterization techniques were employed to assess their physicochemical properties. Colloidal stability was analyzed using analytical centrifugation, while foamability and foam stability were evaluated under CO₂ and N₂ environments using a Dynamic Foam Analyzer (DFA 100). The results demonstrate that surface chemistry, pH, and gas environment are critical parameters influencing interfacial rheology and particle-mediated stabilization mechanisms. Notably, the engineered nanoparticles exhibited colloidal stability and foam stabilization without the use of conventional surfactants under acidic conditions. This study offers valuable insights into the design of stimuli-responsive nanomaterials for applications in enhanced oil recovery (EOR) and CO₂ capture, and contrasts their performance with traditional surfactant-based systems.19 0Item Restricted Design of a Capacity Planning Model for Rural Healthcare.(Saudi Digital Library, 2025) Mira, Mohammed Talal; Kay, Michael GProper healthcare accessibility is a result of a well capacity planning and resource allocations. Reducing waiting times is crucial for all businesses in general, and a mandatory for health services. Prolonged waiting periods can lead to lost sales, dissatisfied customers, and a tarnished reputation. Effective staff requirement planning plays a vital role in minimizing average queue times. In Chapter 2of this study, we introduced a delay penalty that uses opportunity costs and the Value of a Statistical Life (VSL) to quantify the monetary value of patients waiting time. Then we present a comprehensive capacity planning model that takes into account the monetary value of patients’ waiting time. By considering this value, the model identifies the optimal capacity level aimed at enhancing overall effectiveness and outcomes within healthcare organizations, going beyond a sole focus on maximizing profits. The proposed model strikes a balance between capacity costs and customers’ waiting costs by integrating the delay penalty. We employed a MATLAB simulation code to estimate cycle times for transient conditions for most service systems, emphasizing its role in providing accurate estimations, while the closed-form formulas of Queuing Theory were exclusively used for steady-state conditions. This distinction ensures a comprehensive evaluation of waiting times and their associated costs. To evaluate the model’s effectiveness, we applied it to two inferred models from the healthcare industry and compared the current settings with the optimal ones derived from our approach. The results revealed that the optimal settings significantly reduced waiting times and increased profits. Consequently, our proposed model holds immense potential for aiding service organizations in achieving optimal staff planning and resource allocation. In Chapter 3, we developed a Non-Linear Optimization (NLO) model that considers the spatial factor of healthcare accessibility to improve accessibility in rural areas. Although the U.S. spending on healthcare per capita is double that in other developed countries, the accessibility and quality of care are not as good as in most countries. The increased number of rural hospital closures in the United States has severely affected rural communities, which represent 20% of the U.S. population. Private companies, taking over many of the healthcare systems in the United States, decided to stop their operations in rural areas to improve their efficiency and cut costs. This decision made their costs better. However, it increases the overall costs for patients, not necessarily out-of-pocket costs, but in addition, the opportunity costs that include the lost opportunity for taking time out-of-work as people need to travel longer and, more importantly, health deterioration and lives lost as some people are dying just because they are not getting treatment as early as possible. To mitigate the impact of hospital closure, this research proposes a novel approach that incorporates a non-linear exponential distance decay function in a facility location-allocation optimization model to optimally locate telemedicine clinics that can duplicate most of the services offered in the traditional hospital by taking advantage of the enhanced technology. To demonstrate this, we used the model to propose optimal telemedicine urology clinic locations in Texas. This can allow a larger percentage of rural populations access to the service, compared to the current 42%. This model can be applied to the remaining states, which can eventually lead to mitigating the negative impact of hospital closure on people living in underserved areas. Finally, in Chapter 4, we introduced an accessibility metric that integrates spatial and nonspatial factors. The floating catchment area (FCA) and the gravity models are often used to measure spatial accessibility to healthcare services. These models successfully considered the spatial factor to ensure proximity to services. However, proximity to the service without accounting for access time does not accurately describe accessibility. Although some improved versions of the FCA, such as the two-step floating catchment area (2SFCA) and the enhanced (2SFCA), have included the Huff Model to account for the size of the service, this does not provide a precise measure of accessibility. It is proven that waiting time can be a barrier to receiving healthcare services. In this work, we integrate waiting time instead of the capacity size, through a time decay function that utilizes the time to treatment initiation curve (TTI), to measure accessibility. A Non-linear Facility Location, Demand & Resource Allocations Model (NL-FLAM) with an embedded simulation model is then introduced to maximize healthcare accessibility based on the newly introduced definition. This macro-level capacity planning model simultaneously determines the optimal facility locations and the optimal number of providers to serve each proposed location. The distance-decay function estimates the potential demand that is then used by the embedded transient state simulation model to estimate the expected waiting time at each proposed location. Estimated waiting time is then used to estimate survival probability using the TTI curve. To demonstrate its applicability and usefulness, we used the proposed model to propose the optimal locations of urology’s clinics and the number of providers needed to increase the accessibility of Vermont rural patients to this service. This model can be used by public health authorities to help making decisions that utilize telemedicine to mitigate the impact of the rural hospital closure phenomena in the United States.11 0Item Restricted Exploration of Predisposing and Enabling Factors Associated with Non-Adherence to Postpartum Visits among Arab Immigrant Women in New Jersey(Saudi Digital Library, 2025-05-18) Mobarki, Abeer; Hawkins, Charlotte ThomasABSTRACT OF THE DISSERTATION Factors Associated with Non-Adherence to Postpartum Visits among Arab Immigrant Women in New Jersey by ABEER M. MOBARKI Dissertation Directors: Dr. Charlotte Thomas-Hawkins The underutilization of postpartum care is a global problem that limits the early detection of physical and mental health complications during the postpartum period. Yet, there are few investigations of the underlying issues and even fewer investigations about immigrant women in the U.S. and their adherence to scheduled postpartum visits and factors that contribute to their non-adherence. Purpose: This study examined the interrelationships among acculturation oriented to Arabic culture, diminished social support, negative postpartum care beliefs, insurance status, and postpartum visit non-adherence among Arab immigrant women in New Jersey (NJ). Hypotheses: Five hypotheses were tested: 1) Acculturation oriented to Arabic culture is significantly associated with non-adherence to postpartum visits; 2) Diminished social support is significantly associated with non-adherence to postpartum visits; 3) Negative postpartum care beliefs are significantly associated with non-adherence to postpartum visits; 4) Public health insurance status or having no health insurance is significantly associated with non-adherence to postpartum visits; and 5) Acculturation oriented to Arabic culture, diminished social support, negative postpartum care beliefs, Public or no health insurance status are independent predictors of non-adherence to postpartum visits. Methods: This study employed a cross-sectional, correlational design. Foreign-born immigrant women who self-identified as Arab, delivered a child within the past two years, and spoke Arabic or English fluently were recruited from mosques and community centers in northern New Jersey and invited to complete the study survey. A single-item measure of postpartum visit non-adherence was used. The Arabic and English Versions of the Acculturation Rating Scale (ARSMA-II) for Arab immigrants were used to assess acculturation orientation level. The Arabic version of the Multidimensional Scale of Perceived Social Support (MSPSS) was used to examine perceived social support. The Postpartum Beliefs Questionnaire was used to examine beliefs about the postpartum. Results: One hundred thirty-eight Arab immigrant women comprised the study sample. Sixty-eight percent of participants reported non-adherence to postpartum visits. Acculturation oriented to Arabic culture, diminished social support, negative postpartum care beliefs, and insurance status had significant individual effects on the odds of postpartum visits non-adherence. Diminished social support and low perceived susceptibility to postpartum problems had significant independent direct effects on the odds of postpartum visits non-adherence. Conclusion: The findings from this study can inform tailored interventions to 1) address factors that impede postpartum care and 2) increase the utilization of postpartum care services among immigrant Arab women.8 0Item Restricted INTEGRATING LEARNER-CENTERED TEACHING PRACTICES WITH SAUDI ARABIA’S NATIONAL CURRICULUM IN EARLY CHILDHOOD EDUCATION: A MIXED METHODS STUDY(Saudi Digital Library, 2025-06-26) Alibrahim, Alae; GRACE JEPKEMBOI, COMMITTEE CHAIR JULIE PAUL FLANNERY, COMMITTEE CO-CHAIR JENIFFER PONDER KELLY HILL MARIAH WEBERThis study explores how early childhood educators in Northern Saudi Arabia implement learner-centered teaching (LCT) within the framework of the National Curriculum. Employing an explanatory sequential mixed-methods design, the research first collected quantitative data via a survey of 260 teachers, followed by qualitative data through interviews with eight participants. The integrated findings offer a comprehensive understanding of how LCT is practiced in early childhood education. The findings reveal that educators generally recognize the benefits of LCT, particularly in fostering independent learning, critical thinking, and active student participation. Teachers reported using strategies such as open-ended questioning, collaborative learning, and activity-based instruction to support diverse learning needs. However, several barriers hindered full implementation, including large class sizes, limited resources, insufficient professional development, and inconsistent administrative support. Qualitative insights highlighted teachers’ efforts to adapt the National Curriculum in ways that align with student interests and inquiry-based approaches. Many educators view the curriculum as flexible and capable of accommodating child-centered methods. Despite the availability of training opportunities, professional development was often voluntary, leaving gaps in teachers’ preparedness for effective LCT integration. Support mechanisms such as peer collaboration, both online and in-person training, and administrative facilitation of experiential learning activities were also noted. Nevertheless, the inconsistency in access to these supports points to the need for more structured and mandatory professional development programs. Overall, the study underscores both the promise and challenges of implementing learner-centered teaching in early childhood education in the region. While teachers are conceptually aligned with LCT principles, practical constraints and limited institutional backing hinder their ability to apply these methods consistently. These findings suggest a need for policy enhancements that prioritize resource allocation, compulsory teacher training, and structural support to promote meaningful adoption of LCT across early childhood settings.16 0