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    Investigating Transcriptomic Changes Associated with Unilateral Condylar Hyperplasia
    Khoury, Rita Pamela; Ghafari, Joseph; Macari, Anthony; Shirinian , Margret; Kurban, Mazen; MS; Department of Dentofacial Medicine; Faculty of Medicine; American University of Beirut
    Background: Unilateral condylar hyperplasia (UCH) is a self-limiting condition predominantly affecting females between the ages of 11 and 30 years, characterized by non-neoplastic overgrowth of one mandibular condyle leading to progressive maxillofacial asymmetry and malocclusion. Numerous hypotheses have been proposed to explain the etiology of UCH; however, these theories remain inconclusive, and the underlying molecular mechanisms have not been fully investigated and remain poorly understood. While a limited number of studies have investigated UCH using approaches such as single-cell transcriptomics, the global transcriptomic profile of human UCH condylar tissue has not yet been comprehensively explored. Aims: 1 To investigate the transcriptomic signature of UCH through RNA sequencing. 2. To analyze changes in gene expression patterns in affected subjects. 3. To investigate the correlation between condylar length and the severity of mandibular asymmetry in UCH patients. Materials and methods: Seven patients diagnosed with active UCH scheduled for high condylectomy followed by orthognathic surgery were included in the study. Left over affected condylar tissues and unaffected mandibular tissues were obtained during surgery. For downstream transcriptomic analysis, four patients matched in age, sex, and surgical procedure were selected to minimize variability. Total RNA was extracted from the collected tissues and sequencing was performed on the NextSeq 500 platform (Illumina) using a mid-output flow cell configuration. Targeted gene expression analysis was performed to investigate transcriptomic changes associated with UCH, and radiographic measurements were used to evaluate the relationship between linear and angular mandibular measurements. Results: Seven patients with active UCH were included (mean age 22.07 ± 4.43 years), with a predominance of females (71.4%). Right-sided involvement was observed in four patients (57.1%). Due to sample quality constraints, downstream transcriptomic analysis was ultimately restricted to one matched patient. Targeted gene expression analysis revealed increased expression of genes associated with osteogenic differentiation (RUNX2, SP7, SOX9), extracellular matrix organization and collagen remodeling (COL1A1, COL1A2, COL2A1, COL5A2, COL10A1, ACAN, SPARC, POSTN, LOX, PLOD2, OGN), and growth factor signaling (TGFB2, IGF1), whereas VEGFA, implicated in angiogenic growth signaling, was downregulated. Genes involved in epigenetic regulation and chromatin remodeling demonstrated differential modulation, including increased expression of histone demethylases (JMJD1C) and reduced expression of key transcriptional repressors (DNMT1, HDAC4, PHC2). Within the matrix remodeling pathway, MMP13 was upregulated, whereas inflammatory-associated gene MMP3 was downregulated. In the estrogen signaling pathway, GPER1 was downregulated, while ESR1 and ESR2 showed comparable expression between tissues. Radiographic analysis demonstrated only a statistically significant difference in ramal height (Co–Go) between males and females on both the affected (p = 0.03) and unaffected sides (p = 0.01). Correlation analysis revealed strong bilateral associations among mandibular linear measurements, particularly between condylar length and ramal height on the affected and unaffected sides Conclusion: The findings suggest that UCH is primarily associated with enhanced osteochondral differentiation and extracellular matrix remodeling rather than inflammatory, angiogenic, or estrogen receptor transcription-driven processes. The observed gene expression profile indicates activation of pathways involved in bone formation and matrix organization within the affected condyle, occurring within a transcriptionally permissive epigenetic context. Radiographic evaluation further indicates that skeletal linear mandibular measurements, particularly condylar length and ramal height, are strongly interrelated, whereas incisor tipping likely represents compensatory dentoalveolar adaptations to skeletal asymmetry rather than a direct indicator of its severity. As the transcriptomic analysis was exploratory and limited by sample size, these observations require validation in larger cohorts. These results provide novel transcriptomic insight into the molecular mechanisms underlying condylar overgrowth and highlight potential targets for future investigation.
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    CFD-PBM Modeling of Gas-Liquid Flow Through Screen-Type Static Mixers
    Nicolas, Charbel; Azizi, Fouad; Zeaiter, Joseph; Saad, Walid; ME; Baha and Walid Bassatne Department of Chemical Engineering and Advanced Energy; Maroun Semaan Faculty of Engineering and Architecture; American University of Beirut
    Gas-liquid flows are central to many chemical and environmental processes, where phase interactions govern bubble-size distribution, interfacial area, mass transfer, and overall reactor performance. Their significance is amplified in process intensification, where compact equipment is used to enhance transport rates while reducing operating volume and energy consumption. Screen-type static mixers are particularly relevant in this context, since they have been successfully applied to intensify gas-liquid operations such as oxygenation, ozonation, and carbon capture. However, the woven structure of screen mixers, together with their micro-scale openings, make fully resolved numerical simulations computationally expensive. This limitation motivates the use of a reduced geometric representation of these mixers that preserve the dominant hydrodynamic effects while remaining computationally manageable. In this work, a coupled computational fluid dynamics and population balance model (CFD-PBM) framework is developed and evaluated to predict the hydrodynamics and bubble-size evolution of gas-liquid flows through a reactor equipped with screen-type static mixers. Simulations are performed using a finite volume solver (ANSYS Fluent) using an Eulerian-Eulerian multiphase model. The dispersed gas phase is modeled using a class-based population balance approach, with bubble breakup and coalescence described via modified kernels from the literature. Mesh reliability is assessed through a grid convergence index analysis, and the model is validated against experimental measurements of pressure drop and mean bubble diameter. The results indicate that screens act as localized turbulence generators, concentrating energy dissipation over a short downstream distance and promoting bubble breakup in these regions. Farther downstream, as turbulence dissipation subsides, coalescence becomes the dominant mechanism. The coupled CFD-PBM model successfully reproduces this behavior, accurately predicting the axial evolution of bubble size along the reactor as well as the effect of solution contaminants on the dispersed phase behavior. Overall, the model reproduces the key physical mechanisms governing gas-liquid flow through screen-type static mixers. This thesis demonstrates that coupled CFD-PBM modeling provides a robust and physically consistent framework for analyzing turbulent gas-liquid dispersions in intensified systems such as screen-type static mixers. Moreover, the reduced-geometry approach is shown to deliver reliable predictions at a significantly lower computational cost compared to fully resolved simulations.
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    Geographical And Temporal Patterns of Suicide in Lebanon (2021–2025) And Their Association with Baseline District-Level Socioeconomic Conditions and National Crises
    Tawil, Rewa; Al Hajj, Samar; Ghandour, Lilian; El Asmar, Khalil; Mowafi, Hani; MS; Department of Epidemiology and Biostatistics; Faculty of Health Sciences; American University of Beirut
    Background: Suicide is a preventable public health problem worldwide, with higher burden among young people and populations in low- and middle-income countries. Reported rates in the Middle East and North Africa region remain low, with strong evidence of underestimation due to stigma and weak surveillance systems. Lebanon has faced prolonged social, political, and economic crises since 2019, placing pressure on health systems and influencing suicide related outcomes. National research describes trends and psychosocial risk factors, while structural and geographic analyses remain limited. Objective: This study provides the first district level analysis of suicide deaths in Lebanon between 2021 and 2025. It examines associations with socioeconomic deprivation, geographic variation, and exposure to national crises using multilevel models. Methods: This secondary data analysis links Internal Security Forces suicide death records from 2021 to 2025 with district socioeconomic indicators and national crisis measures. Multilevel mixed effects Poisson regression models with district and year random effects estimate incidence rate ratios with population offsets. The analysis includes descriptive assessment of geographic and temporal patterns. Sensitivity analyses test alternative socioeconomic definitions, crisis definitions, model structures, underreporting scenarios, and influential districts. Results: Strong geographic differences in suicide deaths appear across districts. The absence of statistically significant association exists between district socioeconomic deprivation and suicide outcomes after adjustment. Crisis indicators show no consistent association with suicide deaths. No effect modification by socioeconomic status appears. Findings remain stable across all sensitivity analyses.
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    Focus Group Verbatim Notes, Athlete–Public Partnership (APP) Study, Lebanon, October 2023
    (2023-10-09) Rami Elhusseini; Elie-Jacques Fares
    The dataset contains verbatim notes from four focus groups conducted in Lebanon between 2 and 9 October 2023 as part of the Athlete–Public Partnership (APP) study (N = 50). The focus groups were convened to document participant-generated research priorities in sports nutrition and sports science, and to measure the distance between those priorities and a researcher-defined agenda using the Jaccard Similarity Index (JSI) as a co-design integrity metric. Participants across the four sessions included varsity athletes, gym instructors, coaches, and a sports medicine specialist. Session themes ranged from supplement validation, lipid profiles, and anabolic steroid use to injury prevention, sports psychology, female reproductive health, and muscle recovery timelines. JSI scores across sessions ranged from 0.00 to 0.43, indicating that between 57% and 100% of participant-generated priorities had no counterpart in the original researcher agenda. The study was approved by the Institutional Review Board of the American University of Beirut (IRB ID: SBS-2023-0140, approved 22 September 2023, Type: Initial, Exempt)
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    Incorporation of Marine Microplastics and Debris into Eco-Friendly Construction Materials – Application on Concrete Panels
    Al Akoum , Carine; Mabsout, Mounir; El-Khatib , Helmi; Salam, Darine; Yehya, Alissar; ME; Department of Civil and Environmental Engineering; Maroun Semaan Faculty of Engineering and Architecture; American University of Beirut
    Modern infrastructure, with its varied assets, relies on two basic pillar components: concrete and cement. However, the extensive need for these elements creates a big strain on the levels of the global economy and the environment. This is interpreted by the current rising prices of concrete, which result normally from the increasing cost of raw ingredients and the supply limitations with the diminution of natural sand and other aggregates, knowing that these are naturally categorized as non-renewable resources and that they are, unfortunately, extracted at unviable or unsustainable rates. It's beyond question that the unsustainable extraction of resources like sand and gravel at such an increasing rate would lead to diminishing natural resources and disrupted environmental rhythms with altered waterways- all moving parallel with the current increasing demand for these materials. On the other side of the picture, we can observe a parallel environmental issue, which is the uncontrollable accumulation of plastic waste in aquatic environments. The amount of plastic dumped into oceans is estimated in millions of tons each year, all at the sake of the marine ecosystems, the diversity of marine populations, and the related humans' means of subsistence. The rationale underpinning the solution for this issue lies in innovative measures of recovering and reusing these plastic wastes. Thus, this research aims to create a common approach that tackles both issues. It mainly addresses the substitution of aggregates- whether fine or coarse or both combined- with fine or coarse plastics wastes thrown in marine areas. The approach will reflect in less reliance on mined aggregates, lower production costs of concrete, and an eco-friendly handling of plastic wastes. Extensive experimentations will be carried on various blends and mixtures of these substitutes, to determine the best plastics replacement approach. Consequently, further investigations and different replacements ratios will be assessed for the selected plastics type in order to study their mechanical behavior. Finally, the findings of these experimentations will facilitate the use of the ideal mixes in the production of masonry blockworks and concrete panels. The envisioned outcome of this study is to find a cost- efficient and resource-conscious alternative for concrete and cement-based materials that serves the demand for quality constructive material, reduces environmental exhaustion of natural aggregates, and helps solve the hazards of plastic wastes. This research will incorporate waste recovery techniques and wise environmental planning to create a highly-demanded construction material at lower costs and high quality. This will reflect on mutual sustainability in both industry and environment.