SACM - United States of America
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Item Restricted Bacterial Chondronecrosis with Osteomyelitis in Broilers: Etiology and Selected Mitigation Measures(Saudi Digital Library, 2025-07-13) Alharbi, Khawla; Alrubaye, AdnanBacterial chondronecrosis with osteomyelitis (BCO) is the predominant cause of lameness in broiler chickens. It mainly impacts broiler production and animal welfare, causing substantial financial losses accounting for 1- 2% due to bird condemnations at the marketing age. Remediating BCO lameness disease demands investigating its causes using appropriate models and evaluating preventive measures, such as enhancing epithelial tissue health and tight junction integrity in the digestive and respiratory tract, strengthening immune functions, and improving bone strength. Therefore, the objectives of this dissertation were to 1) study predisposing factors for BCO lameness by investigating the effects of deoxynivalenol (DON) and fumonisin (FUM) mycotoxins contamination on BCO lameness by exposing broilers reared on wire (W) and litter flooring (L) to diets contaminated with mycotoxins (MTX), 2) determine the efficacy of adding different combinations of 1,25-Dihydroxyvitamin D3-glycoside (G-1,25(OH)2D3) and phytogenic antioxidants on improving bone and gut health and the immune system 3) investigate the optimal timing for adding Availa® ZMC to broiler diets to mitigate BCO lameness, reduce feed additive costs, and effectively protect against BCO lameness. As a result, the findings in this dissertation include three main significant areas. First, increasing the incidence of BCO lameness using mycotoxins due to increasing intestinal permeability supports a correlation between intestinal barrier integrity and BCO lameness and suggests that DON and FUM mycotoxins are predisposing factors for increasing BCO. Second, no significant difference in protection against BCO when supplementing 1.0 µg G-1,25(OH)2D3 individually or in conjunction with polyherbal mixtures or Thyme oil. In addition, increasing the G-1,25(OH)2D3 dosage from 1.0 µg/kg to 10 µg/kg did not yield a lower lameness incidence beyond the low dosage. Finally, incorporating 0.15% Availa® ZMC supplementation into the broiler diet during the initial 28 days is considered ideal for the 0.15% Availa® ZMC dose compared to adding 0.15% Availa® ZMC for the entire production cycle. In conclusion, this collection of studies provides valuable insights into understanding the etiology of BCO lameness and finding possible ways to prevent and remediate its occurrences.18 0Item Restricted TELEMEDICINE IN POST-EMERGENCY DEPARTMENT FOLLOW-UP FOR UNCONTROLLED HYPERTENSION: PREVALENCE AND MODALITY CHOICE FACTORS(Saudi Digital Library, 2025-04-14) ALSHAIKH, ABDULAZIZ; YOUNGRAN, KIMHypertension remains a leading public health concern, contributing to a significant burden of emergency department (ED) visits, particularly when blood pressure is poorly controlled. Patients who visit the ED for uncontrolled hypertension often require timely follow-up care to prevent recurrent ED visits, hospitalizations, and long-term complications. However, gaps in continuity of care post-ED discharge persist, with a substantial proportion of patients failing to receive appropriate outpatient follow-up. The COVID-19 pandemic accelerated the adoption of telemedicine, offering an alternative modality for post-ED follow-up care. Despite the increased availability of virtual care, the extent to which telemedicine is utilized for follow-up after an ED visit for uncontrolled hypertension remains unclear. Moreover, there is limited research comparing the timing of telemedicine versus in-person follow-up or identifying the factors associated with the selection of follow-up modality. This research aims to address these gaps by examining the prevalence of telemedicine versus in-person follow-up visits after an ED visit for uncontrolled hypertension, assessing the time interval between ED discharge and follow-up care by modality, and determining the demographic and clinical characteristics influencing follow-up modality selection. By leveraging U.S. commercial insurance claims data from 2021–2022, this study provides real world insights into the use of telemedicine in hypertension management, informing future strategies to enhance continuity of care, and reduce healthcare differences. v3 0Item Restricted Estimating the Impact of Co-localized Risk Variables on Peri-implant Diseases(University of Michigan, 2025) Albaqawi, Hoda; Purnima, KumarThis study hypothesizes that peri-implant diseases, including peri-implant mucositis and peri- implantitis, result from the combined influence of site-level anatomical factors and patient-level behavioral or systemic characteristics. Specifically, features such as inadequate gingival attachment, shallow vestibular depth, and poor interproximal hygiene access significantly increase the risk of disease onset and progression. Peri-implant diseased states are associated with distinct shifts in the peri-implant microbiome, marked by a transition from health-associated commensals to pathogenic, dysbiotic microbial communities. The aim of this study is to quantify the contribution of site-level and patient-level variables to peri-implant disease risk using multivariate modeling and machine learning techniques. Materials & Methods: In this cross-sectional analysis, 240 participants with single, non-splinted implants in function for at least one year were enrolled. Clinical and radiographic assessments categorized implants as healthy (n = 72), peri-implant mucositis (n = 135), or peri-implantitis (n = 33). Site-level factors (gingival attachment, keratinized mucosa, vestibular depth, plaque and inflammation indices, implant position) and patient-level variables (age, hygiene behavior) were analyzed using multinomial logistic regression and Random Forest classification. Linear Discriminant Analysis (LDA) of Bray-Curtis distances was applied to examine clustering based on combined variables. Results: Of the 240 implants analyzed, 47.1% were healthy, 40.4% had mucositis, and 12.5% had peri- implantitis. Multinomial logistic regression identified gingival attachment (GA <1 mm) and vestibular depth (VD <11 mm) as the strongest predictors of disease, with odds ratios of 4.2 and 7.8. The covaiate risk of the Interaction effects between shallow VD and inadequate keratinized mucosa (KM) significantly elevated mucositis risk. Implant adjacency without tooth support, shorter implant length, and posterior positioning were associated with peri-implantitis. The Modified Plaque Index (mPI) consistently predicted both disease states, with its impact intensified in sites with reduced GA, shallow VD, or limited KM. Random Forest models further highlighted age, interproximal hygiene access, and anatomical constraints as key features, achieving over 95% accuracy in disease classification. Conclusions: In conclusion, this study reinforces the multifactorial and interdependent nature of peri-implant disease risk. By integrating site-level and patient-level variables into a unified framework, we provide novel insights into how co-localized factors synergize to influence disease onset and progression. These findings advocate for early identification of site-level disease predictors, and preventive approach in implant therapy, highlighting the importance of individualized treatment planning and maintenance strategies for optimal long-term outcomes.8 0Item Restricted Large-scale Measurements to Assess the Impact of Middleboxes on the Internet’s Reliability(Saudi Digital Library, 2025-07-13) Alaraj, Abdulrahman Abdullah S; Eric, WustrowThe fundamental design principle that shaped the architecture of the early Internet, namely the end-to-end argument, has been undermined by the expansion and the resulting complexity of more developed stages of the Internet. The middle fabric of today’s Internet underwent numerous stages of development which offered tangible improvements to the Internet’s usability and reliability despite violating the cherished design principle. In tandem with this development, researchers have extensively studied middleboxes—a core element to the middle fabric. Nevertheless, with the continuous growth and complexity of this part of the Internet, under-explored research avenues emerge. In this dissertation, I present a series of large-scale Internet measurements that reveal how middleboxes, while integral to the successful expansion of the Internet, can compromise its reliability. First, I examine the role that nation-state censorship middleboxes can play in launching unprecedented TCP reflected amplification attacks that can produce virtually inexhaustible amplification rendering Denial of Service (DoS) attacks more powerful than ever presumed. Second, I investigate how network misconfigurations can cause persistent routing loops that can be abused to launch DoS attacks, and show that contrary to the common belief, middleboxes, not exclusively routers or managed switches, can cause this faulty behavior. Third, I study the censorship of circumvention proxies that affects millions of Internet users in Iran, and present evidence that challenges an established notion of censorship monolithism in Iran. Indeed, this diversity of censorship deployments complicates the circumvention landscape, requiring ISP-specific circumvention strategies to individually combat heterogeneous censorship middleboxes. Finally, I present measurements that demonstrates how the performance of on-path censorship middleboxes can be degraded without impacting the underlying network, thereby highlighting the significant risks from degraded Internet connectivity had these middleboxes been deployed in-path. Through these large-scale measurements, this dissertation argues that the evolving complexity of middleboxes introduces both new challenges and opportunities for improving the Internet’s reliability.9 0Item Embargo AI-Enabled Bioresponsive Clinical Decision Support Systems for Chronic Pain: User-Centered Approach(Saudi Digital Library, 0025) Alrefaei, Doaa; Soussan, DjamasbiThe advancement of eye-tracking technologies has enabled the development of systems capable of detecting attention and cognitive states objectively and in real time. Biometric technologies that capture psychological measures, such as eye movements (EMs), have allowed user experience (UX) research to expand toward building smart bioresponsive tools. One area that may benefit from these advancements is chronic pain, where self-report methods are often limited in capturing the complex phenomenon of chronic pain experience in both research and practice. This has established a need for objective biomarkers that can support pain assessment. Pain literature suggests the use of EMs as potential biomarkers, as they reflect pain-related attentional patterns. This dissertation adopts a bioresponsive, UX research approach to explore the efficacy of using EMs to detect pain experience in individuals with and without chronic pain. A proof-of-concept AI tool was developed to detect chronic pain using only EMs from individuals with and without chronic pain, achieving an accuracy of 81%, thereby demonstrating the robustness of EMs as a potential biomarker for pain. To successfully evolve this proof of concept into a fully developed and effective Clinical Decision Support System (CDSS) for chronic pain treatment and management, it is essential to understand the needs of the healthcare professionals who will use the system. As a first step, traditional UX research methods were employed to conduct interviews with healthcare professionals involved in the treatment and management of chronic pain. Based on this research, six user personas, four representing doctors and two representing nurses, were developed to serve as a foundational guideline for the design of an initial CDSS prototype. The findings of this dissertation contribute to both UX research and pain science by presenting a comprehensive methodology for using eye movements (EMs) as input signals to an AI tool capable of detecting differences in attentional patterns toward pain-related stimuli. It also contributes to clinical practice by outlining design guidelines for developing an initial prototype of such an AI-based CDSS, grounded in the needs and workflows of healthcare professionals.12 0Item Restricted Smart Online Education Platform(Saudi Digital Library, 2025-05-16) Alhotan, Zyad; Christine, KeriganThis thesis presents FHM, an innovative online design education platform tailored for Saudi and Arab learners. Bridging a critical gap in the regional e-learning landscape, FHM integrates four core elements: Arabic-first bilingual instruction, structured mentorship and community engagement, project-based learning with feedback loops, and adaptive pathways aligned with industry needs. The project combines cultural relevance with modern technology to empower Arab creatives through personalized, skill-driven education. Research, branding, UX/UI, motion design, and print deliverables were strategically developed to create a cohesive educational ecosystem. FHM directly supports Saudi Arabia’s Vision 2030 by fostering local creative talent and enhancing access to world-class design learning rooted in cultural identity.15 0Item Restricted The Effect of Changing Medicaid Dental Benefits Type on Dental Services Utilization Among the Adult Population(Saudi Digital Library, 2025) Mogaddam, Meaad; Choi, Sung EunIntroduction: In 2021, Medicaid invested approximately $18 billion in dental care, yet studies show that access remains limited for many low-income adults. One key strategy that states can use to enhance dental care and reduce disparities among low-income adults is increasing the number of covered dental services. However, few studies have explored the impact of changing the Medicaid dental benefit type on dental services utilization among the low-income adult population at the state-level. Additionally, including the perspectives of Medicaid dental offices in each state would deepen our understanding of Medicaid dental benefits for adults. Objectives: 1) to understand the attitudes of state Medicaid dental offices toward the importance of different types of dental benefits on dental care use among Medicaid beneficiaries, and 2) to explore the impact of changing the Medicaid dental benefit type on adult dental service utilization within each state, considering the year of these changes. Hypothesis: upgrading Medicaid dental benefit type would improve dental services utilization. Approach: This cross-sectional study distributed a survey to all 50 states and the District of Colombia (DC) Medicaid dental offices. Also, we used nationally representative Behavioral Risk Factor Surveillance System (BRFSS) data from 2010 to 2020. Our study population included low-income (household income below 138% FPL) adults aged 18 to 64 years. Statistical analysis: Univariate and bivariate analysis using Fisher's exact test were conducted to analyze the survey data. While difference-in-differences (DID) and regression discontinuity (RD) designs were employed to evaluate the association between Medicaid dental benefit changes and dental care utilization, accounting for individual-level and state-level covariates. Results: The survey, with a 65% response rate, revealed strong agreement on the importance of offering more dental services for Medicaid adult beneficiaries, particularly preventive care, and on the importance of expanding Medicaid eligibility criteria. Moreover, all states expressed a positive attitude toward the importance of including various types of dental services, except for teledentistry, which was less prioritized. Regarding Medicaid dental office satisfaction with the provided dental services, a direct relationship was observed: where an increase in the level of dental benefits offered was associated with higher satisfaction levels reported by Medicaid dental offices. For the BRFSS data analysis, eight states were included based on the year and type of dental benefit change (Emergency to Limited: 1 state; Emergency to Extensive: 4 states; and Limited to Extensive: 3 states). The results of DID and RD analyses suggest that, in general, expanding dental benefit type for Medicaid adult beneficiaries would increase the probability of dental service utilization among low-income adults. However, the magnitude of this increase varied by state. Conclusion and future direction: expanding dental benefits for low-income adults seems to be effective. However, other strategies and state-specific factors should be carefully considered when designing interventions aimed at increasing and sustaining dental service utilization. We recommend gaining a deeper understanding of these state-specific factors, by integrating both quantitative and qualitative approaches, to develop a tailored plan for creating targeted and effective interventions.14 0Item Restricted CARDIOVASCULAR SAFETY AND ECONOMIC IMPACT OF ADVANCED THERAPIES IN INFLAMMATORY BOWEL DISEASE: A SYSTEMATIC REVIEW, AND REAL-WORLD EVIDENCE STUDY(Saudi Digital Library, 2025-08-10) Alnahdi, Amirah H; Tianze, JiaoPatients with chronic immune-mediated disorders (IMID), including Inflammatory Bowel Disease (IBD), face an elevated risk of cardiovascular disease and often require advanced therapies that may influence both cardiovascular safety and healthcare costs. This thesis addresses two interrelated aims to better understand these outcomes. The first aim is to conduct a systematic review and meta-analysis of the risk of major adverse cardiovascular events (MACE) associated with advanced therapies compared to conventional treatments in patients with IBD. The second aim involves a real-world, retrospective cohort study evaluating cardiovascular safety and healthcare utilization among biologic-naïve adult IBD patients treated with infliximab reference products versus biosimilars using MarketScan claims data. In the Aim 1, a comprehensive literature search and meta- analysis were conducted to synthesize existing evidence on cardiovascular risks. Indeed, the synthesized evidence from high-quality randomized controlled trials and observational studies did not demonstrate a clear protective effect of advanced therapies on MACE in IBD patients, in contrast to findings observed in other IMIDs. In the Aim 2, a rigorously designed cohort was built with advanced statistical methods applied to compare outcomes, including the incidence rate of MACE, healthcare utilization, and cost within the first year after initiated infliximab reference product or biosimilars. The real-world evidence did not support the anticipated cost savings associated with infliximab biosimilars and provided preliminary evidence suggesting a potential increased cardiovascular risk associated with infliximab biosimilars. In conclusion, these findings underscore the need for ongoing monitoring of cardiovascular risk for advanced therapies and reconsideration the cost difference between reference products and related biosimilars in optimizing IBD management.21 0Item Restricted MULTI-LEVELS OF INFLUENCE ON BULLYING BEHAVIOR AMONG HIGH SCHOOL STUDENTS IN SAUDI ARABIA(Saudi Digital Library, 2025-07-14) Mobarki, Amani; Gwon, JovanBackground: Exposure to bullying behavior can significantly impact the physiological and psychological well-being of affected adolescents. Despite this, there is a lack of literature in Saudi Arabia addressing the various factors influencing bullying behavior among high school students. This study aims to fill some of these gaps by employing modeling analysis to identify the predictive factors that influence the dynamics of bullying behavior. Purpose: To understand multi-levels of influences on bullying behavior among high school students in Saudi Arabia. Methods: The study utilized a quantitative, and cross-sectional descriptive correlation design, with a convenience sampling approach employed to recruit participants. The proposed population was male and female from grades 10, 11, and 12, aged 16 to 20. Participants completed a self-report survey measuring their (a) demographic background information, (b) bullying behaviors (BCS-A), (c) inventory of Parent and Peer Attachment (IPPA), (d) the School Environment Support, and (f) Difficulties in Emotional Regulation Scale (DERS). Descriptive statistics, frequencies, and multiple linear regression were used to analyze the data. Results: The study identified parental attachment, the school environment, and difficulties in emotional regulation as significant predictive factors affecting student outcomes. Additionally, mediation analysis indicated that difficulties in emotional regulation act as both a partial iii and full mediator for bullying behavior. Conclusions: The findings of this study underscore the importance of implementing targeted protective and preventive measures to address bullying within the context of parent-school relationships. There is a clear need for specific strategies to tackle bullying issues in schools. These results have significant implications for stakeholders involved in bullying prevention, including school nurses, mental health professionals, and school psychologists.21 0Item Restricted UNVEILING THE ANTI-VEGF LANDSCAPE: AN INTEGRATIVE STUDY OF COMPARATIVE EFFECTIVENESS, COST-UTILITY, AND PHARMACOVIGILANCE(Saudi Digital Library, 2025-04-04) Baljoon, Ahmead; Matthew DuttonBackground: Intravitreal anti-angiogenic medications have recently grabbed the attention of researchers to control the pathology of neovascular age-related macular degeneration (nAMD) and diabetic macular edema (DME). This thesis aims to assess the differences in efficacy and safety between faricimab and aflibercept in patients with nAMD and DME through a comparative effectiveness analysis, specifically utilizing a meta-analysis approach. Additionally, it seeks to compare the cost-effectiveness of faricimab and aflibercept in nAMD patients from the payer's perspective in the United States. Furthermore, a pharmacovigilance study conducted to assess the real-world safety profile of faricimab in comparison to other anti-VEGF agents. Methods: A systematic review and meta-analysis were conducted by searching four academic databases, focusing on two efficacy outcomes, changes in best-corrected visual acuity (BCVA) and central subfield thickness (CST), as well as three safety outcomes: conjunctival hemorrhage, serious adverse events (SAEs), and all-cause mortality. Standardized mean differences (SMDs) and relative risks were used to summarize the results, providing a comprehensive evaluation of faricimab and aflibercept in managing nAMD and DME. A Markov model was developed to compare faricimab (flexible dosing) and aflibercept over a five-year period, incorporating transition probabilities derived from x pooled estimates of data from two clinical trials and direct medical costs. Sensitivity analyses assessed the impact of key model parameters on cost-effectiveness. Additionally, a pharmacovigilance study evaluated the ocular safety profiles of faricimab, aflibercept, and ranibizumab using adverse event reports from the US FDA Adverse Event Reporting System (FAERS) from Q4/2003 to Q2/2024. The analysis, performed with OpenVigil 2.1, identified potential safety signals using MedDRA classification for AEs. Results: Four RCTs included 3220 patients. Faricimab had a significant lower mean change in CST than aflibercept (SMD = -0.24, 95%CI, -0.39 to -0.10, p = 0.001). BCVA did not differ. Conjunctival hemorrhage, SAEs, and all-cause mortality were similar across treatment arms. Base-case analysis demonstrated that faricimab is a cost-effective option, with a lower total cost ($51,913) and higher effectiveness (3.39 quality-adjusted life years (QALYs)) than aflibercept, which had higher costs ($61,210) and lower QALYs (3.29). Faricimab’s incremental cost-effectiveness ratio (ICER) dominated aflibercept ( $91,787.78 per QALY), reflecting better cost-effectiveness, mainly due to reduced injection frequency and related costs. The study also reports the AEs significantly linked to faricimab, aflibercept, and ranibizumab for the treatment of nAMD and DME. The findings include several novel AEs linked to faricimab, including Idiopathic orbital inflammation, hypopyon, and ocular vasculitis. xi Conclusion: Faricimab and aflibercept offer similar therapeutic benefits in treating retinal vascular diseases. However, further trials are necessary to confirm the significant reduction in central CST with faricimab in the treatment of in nAMD and DME. Faricimab offers superior economic value in treating nAMD in the USA, delivering comparable clinical benefits at lower costs than aflibercept. Its cost-effectiveness and reduced treatment burden support its potential as a preferred option for nAMD management from a payer’s perspective, suggesting benefits for healthcare systems by reducing costs and injection frequency. Faricimab-associated AEs are primarily linked to active inflammatory ocular disorders, while ranibizumab and aflibercept are more often associated with structural eye changes, lens disorders, ocular infections, or surgical effects. However, faricimab's safety profile remains incomplete due to limited post-marketing data.7 0