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Diagnostic Yield of Office-Based Laryngeal Biopsy in Patients With Leukoplakia; A Case Study With Review of the Literature
Get PDFObjective: To review the authors experience in un-sedated office-based biopsies of patients with vocal fold leukoplakia and to review the literature. Material and Method: A retrospective review of 29 patients was conducted. Results: A total of 41 office-based procedures were performed (eight patients had bilateral vocal fold lesions and four patients had the procedure performed twice). In 26 out of the 41 biopsies, the pathology revealed benign lesion. In eight cases, the pathology showed dysplasia (four high-grade and four low-grade). Seven biopsies revealed squamous cell carcinoma. Five patients underwent suspension micro-laryngoscopy for definitive diagnosis. Four of whom had a change in their diagnosis. Conclusion: Un-sedated office-based biopsy of vocal fold leukoplakia is an alternative to suspension microlaryngoscopy in case of carcinoma or nonmalignant lesions. © 202
Extreme energy poverty: The aftermath of Lebanon's economic collapse
Get PDFWe collect primary data by conducting a survey on 931 Lebanese households who work in seven pre-specified sectors across all Lebanese governorates. The survey was supplemented by five groups of Key Informant Interviews that helped in formulating the survey questionnaire and in validating and interpreting the data from the survey. This paper aims to provide an assessment of the extent of energy poverty in Lebanon against comparators. Energy poverty is gauged using three indicators: (i) percentage of households able to keep their household warm, (ii) percentage of income spent on energy and, (iii) the low-income high-cost approach. Our findings uncover that Lebanese households suffer from the highest prevalence of energy poverty amongst comparators and, in absolute (rather than comparative) terms, a very high incidence of energy poverty. The findings underscore the dire need for measures that aim to mitigate the energy poverty of Lebanese households. We prescribe and discuss policy actions to alleviate the drastic situation which is further exacerbated by the ongoing crises. Our actionable policy recommendations are tailored to Lebanon's specificities and cover the different relevant energy sectors; electricity, transportation, cooking, and heating. © 2023 Elsevier Lt
Palatal Rugae in 3D Superimposition Technique
No full textBackground: Superimposition of three-dimensional (3D) digital models on reportedly stable palatal rugae (PR) facilitates the assessment of tooth movement during growth and orthodontic treatment. Available techniques using manual annotation of features on dental casts and photographs are time-consuming and prone to errors.
Objectives: Develop a consistent stable reference frame using the PR and validate their stability and the consistency of an associated reference frame.
Methods: 3D textured intraoral scans of orthodontic patients were manually segmented (using MeshMixer software) to label individual teeth and PR. The segmented scans were colored and separated using MeshLab software. The rugae of same patients were superimposed to verify their stability over-time. Each single ruga, pair of rugae, and the whole PR surface were superimposed to identify the most stable region in different malocclusions and treatment modalities. Superimposition on the most stable area was performed before and after orthodontic treatment to evaluate amount and direction of tooth movement.
Results: Segmentation of the rugae proved efficient as a basis to compare the stability of the rugal components. Superimposition on individual rugae, the mesial part of the 3rd rugae, and 2nd rugae were the most stable references, respectively.
Conclusion: The results indicate the validity of the method. A new contribution is that a single ruga is sufficient as a reference. The findings on the 3rd rugae corroborate previous reports. The method will allow the use of the rugae superimposition to quantify tooth movement and perform more frequently needed evaluations and will minimize reliance on x-rays
Difficulties in Emotion Regulation Among Syrian Refugee Girls: Risk and Protective Factors
Get PDFExposure to war and forced migration have been widely linked to child subsequent adaptation. What remains sparse is research spanningmultiple risk and protective factors and examining their unique, and relative implications to difficulties on emotion dysregulation in refugee girls. This study investigated themechanisms through which emotion dysregulation in Syrian refugee girls is impacted by exposure to war traumas, comorbidities, and other risk and protective factors such as coping styles, family relationships, and school environment. The sample consisted of 539 Syrian refugee girls who ranged in age from 7 to 18 years attending public schools in various governorates in Lebanon and Jordan. Two school counselors carried out the interviews with children at school. Results indicated that war trauma and the combination of comorbidities associated with negative coping styles could lead to an overall state of emotion dysregulation in refugee girls. Enhanced understanding of the mechanistic role of risk and protective factors in contributing to emotion dysregulation in refugee girls may contribute to the development of effective interventions to target the psychological effects of the refugee experience © 2023 Global Alliance for Behavioral Health and Social Justic
Blood pressure, hypertension and the risk of atrial fibrillation: a systematic review and meta-analysis of cohort studies
Get PDFElevated blood pressure and hypertension have been associated with increased risk of atrial fibrillation in a number of epidemiological studies, however, the strength of the association has differed between studies. We conducted a systematic review and meta-analysis of the association between blood pressure and hypertension and atrial fibrillation. PubMed and Embase databases were searched for studies of hypertension and blood pressure and atrial fibrillation up to June 6th 2022. Cohort studies reporting adjusted relative risk (RR) estimates and 95% confidence intervals (CIs) of atrial fibrillation associated with hypertension or blood pressure were included. A random effects model was used to estimate summary RRs. Sixty eight cohort studies were included in the meta-analysis. The summary RR was 1.50 (95% CI: 1.42–1.58, I2 = 98.1%, n = 56 studies) for people with hypertension compared to those without hypertension (1,080,611 cases, 30,539,230 participants), 1.18 (95% CI: 1.16–1.21, I2 = 65.9%, n = 37 studies) per 20 mmHg increase in systolic blood pressure (346,471 cases, 14,569,396 participants), and 1.07 (95% CI: 1.03–1.11, I2 = 91.5%, n = 22 studies) per 10 mmHg increase in diastolic blood pressure (332,867 cases, 14,354,980 participants). There was evidence of a nonlinear association between diastolic blood pressure and atrial fibrillation with a steeper increase in risk at lower levels of diastolic blood pressure, but for systolic blood pressure the association appeared to be linear. For both systolic and diastolic blood pressure, the risk increased even within the normal range of blood pressure and persons at the high end of systolic and diastolic blood pressure around 180/110 mmHg had a 1.8–2.3 fold higher risk of atrial fibrillation compared to those with a blood pressure of 90/60 mmHg. These results suggest that elevated blood pressure and hypertension increases the risk of atrial fibrillation and there is some increase in risk even within the normal range of systolic and diastolic blood pressure. © 2023, The Author(s)
Model-Free Optimal Control of Inverter for Dynamic Voltage Support
Get PDFInverter-based resources (IBRs) are required to provide dynamic voltage support (DVS) during voltage dips to enhance the low-voltage ride-through capability. In this article, a model-free control method is developed to achieve the optimal DVS (ODVS) without relying on the knowledge of grid parameters. Delving into the optimum trajectory of the ODVS problem, it is found that the current constraint and the maximum active power constraint of IBRs are both binding, or one of them is binding. This inspires us to search for the optimum in a closed-loop way by a perturb-and-observe (P&O)-based optimum seeking (OS) controller with either the power factor angle or the reactive current being the manipulated (perturbed) variable. The system is guaranteed to converge asymptotically to the optimum provided the stepsize sequence is diminishing and non-summable. The proposed model-free optimal control is finally implemented within a single-stage photovoltaic (PV) system, where dynamic simulations demonstrate the optimal and fast DVS performance. Moreover, the implementation strategy for other types of IBRs that are not self-protected by nature is also discussed. © 2022 IEEE
Influenza Vaccine Uptake, Hesitancy and their Determinants among Lebanese Public Transportation Drivers during COVID-19
No full textPublic transportation drivers are at a high risk of contracting and are potential super-spreaders of influenza. Protecting them through vaccination needs to be a primary health care (PHC) objective. A scoping review of articles published between 2016 and 2022 indicated that influenza vaccine uptake and hesitancy were not examined among this high-risk population within the Middle East North African (MENA) region.
This cross-sectional study measured the proportion of influenza vaccine uptake among a representative non-probability sample of Lebanese public transportation drivers during the COVID-19 pandemic and examined the determinants of vaccine uptake. The conceptual model of this study was inspired by the Theory of Reasoned Action/ Theory of Planned Behavior (TRA/TPB).
An interviewer-administered survey was conducted between January and March, 2023. A quota sample of 509 public transportation drivers were recruited using convenience sampling from 24 Lebanese districts regardless of their ethnicity, age or gender. A PhD student targeted these drivers at their resting stations, companies, syndicates, and the airport, and invited them to participate in the study. Those who provided verbal consents were included. Independent and predictors variables captured the main constructs of the TRA/TPB (External individual factors, attitude, norms and perceived behavioral control) and the 5Cs hesitancy scales (confidence, complacency, collective responsibility, constraints, and risk calculation). The main outcome was uptake of influenza vaccine and secondary outcome was intention to uptake in upcoming influenza season. Descriptive and bivariate statistical analyses, followed by hierarchical, ordinal, and linear regression analyses were performed. Mediation and cluster analysis were performed. Statistical significance was set at P<0.025 (two sided).
The proportion of drivers who received influenza and COVID-19 vaccine uptake was 28.9% and 71.7%, respectively. Moreover, 56.2% drivers intended to take the influenza vaccine in the upcoming influenza season if it will be offered for free, at a discounted price, or through a mobile vaccine clinic.
Statistically significant determinants of influenza vaccine intent were: residing in Beirut or Mount Lebanon (adj.OR=1.28 [1.03-1.59]), being exposed to advice on influenza vaccine uptake (adj.OR=1.48 [1.21-1.83]), those who reported average financial status (adj.OR=0.71 [0.57-0.89]). Drivers who were not confident in influenza vaccines were (adj.OR=0.64 [0.51-0.81]) times less likely to take the vaccine in the future. Drivers who believed that influenza vaccines are advertised for commercial profiteering and those who preferred natural immunity over vaccines, were both less likely to get influenza vaccination in the future.
Statistically significant determinants of influenza vaccine uptake were: knowing a family, friend, or colleague who took the influenza vaccine (descriptive norm) (adj.OR=4.55[2.55-7.98]), advice by a family, friend, or colleague on taking the influenza vaccines (subjective norm) (adj.OR=2.16[1.15-4.07]), previous influenza infection (adj.OR=1.71[1.17-2.49]), COVID-19 vaccine uptake (adj.OR=11.39[4.84-26.83]), lack of confidence (adj.OR=0.81[0.66-0.99]), risk calculation (weighing the risks versus benefits of vaccines) (0.78[0.64-0.95]), and an interaction between the hesitancy dimension related to constraints and behavioral control 0.81[0.69-0.91].
Hierarchical cluster analysis showed two subgroups within the sample. Those drivers who were more likely to get the influenza vaccine had more work experience, were financially more comfortable, visited a physician annually, had better knowledge, had better perceptions of vaccine benefits, and had higher perceived severity of influenza. This subgroup reported higher influenza vaccine uptake compared to the other counter groups who had lower vaccine uptake.
Findings in this study are of particular interest to the Lebanese Ministry of Public Health, Directorate General of Land Transportation and Drivers' syndicates. Public transportation drivers can benefit from tailored interventions such as awareness campaigns to enhance their knowledge of influenza and its vaccines, alleviate their hesitancy, guide them to vaccine providers and support them to overcome any barrier such as vaccine cost and accessibility. At a global level, more research is needed targeting public transportation sector to assess their intention and uptake of influenza vaccine as well as to design interventional studies that can promote influenza vaccine uptake among drivers and subsequently public safety from influenza outbreaks
Methodology and Application of Ductile Damage Modeling on Double Tee and Extended Endplate Connections
Get PDFThe postyield ductile damage of steel structures is gaining the interest of researchers and designers alike. The ability to model and quantify the damage of structural steel is the focus of this research and a novel approach that relies on micromechanical theories is presented to develop the finite element (FE) model for the ductile damage of double Tee and extended endplate connections. First, a methodology is presented to guide researchers and designers on how to model the FE fracture of steel material subjected to combined tensile and shear loadings using two built-in ductile damage models in ABAQUS [the Stress Modified Critical Strain (SMCS) and the Hooputra models]. Second, several steel base materials (A992, A572-50, and A36) and bolt materials (A325 and A490) are calibrated for use in both ductile damage models (SMCS and Hooputra). Third, FE fracture models are developed and validated against experimental results, available in the literature, of double Tee and extended endplate connections subjected to monotonic and cyclic loadings. The results show that the proposed FE fracture model predicts the failure mode and load-displacement response of double Tees and extended endplates with at most 9.5% deviation for the displacement at fracture and 7.8% deviation for the ultimate load. The FE fracture model predicts the postultimate strength and ductility required for seismic applications. Also, the FE fracture model predicts crack initiation in base or bolt material due to tensile and/or shear loadings. In a broader perspective, this research enables design engineers to accurately predict the postultimate behavior of steel connections with ease. The research also aims at including the fracture characteristics of steel material in the current design guidelines of steel connections. © 2022 American Society of Civil Engineers
LEBANON’S LANGUAGE TRILOGY: THE USE OF FRENCH, ENGLISH, AND ARABIC IN THE LINGUISTIC LANDSCAPE OF NEIGHBORHOODS IN RAS BEIRUT, ASHRAFIEH, AND GHAZIEH
No full textLebanon's multifaceted history has paved the way for an ever-transforming landscape and identity. Using a linguistic landscape (LL) approach, this study examines the use of English, French, and Arabic in the signs of privately-owned shops in three neighborhoods in Lebanon. These include Ras Beirut, which is home to the American University of Beirut (AUB), Ashrafieh, which is home to Saint Joseph University (USJ), as well as the southern town of Ghazieh, located 4.9 kilometers south of the city of Saida. Ghazieh has had no influence from Western missionaries throughout its history and has no universities present in its locality, making it of interest to the study for the purpose of comparing the use of foreign languages on shop signs in Lebanon. The study aims to provide insight into the role of globalization and the spread of the English language and its impact on commercial considerations in shaping the linguistic landscape of Lebanon
Comparisons between young adult waterpipe smokers and nonsmokers’ reactions to pictorial health warning labels in Lebanon: a randomized crossover experimental study
Get PDFThis study compares the impact of pictorial health warning labels (HWLs) and their placements pton waterpipe parts (device, tobacco and charcoal packages) on health communication outcomes between waterpipe smokers and nonsmokers in Lebanon. An online randomized crossover experimental study was conducted among young adults (n = 403, August 2021) who observed three conditions of HWLs: pictorial HWLs on the tobacco package, pictorial HWLs on all waterpipe’s parts and text-only HWL on the tobacco package in random order. Participants completed post-exposure assessments of health communication outcomes after each image. Using linear mixed models, we examined the differences in the effect of HWL conditions on several outcomes (i.e. warning reactions) between waterpipe smokers and nonsmokers, controlling for confounders (i.e. age, sex). Nonsmokers reported greater attention (β = 0.54 [95% confidence interval: 0.25–0.82]), cognitive elaboration (0.31 [0.05–0.58]) and social interaction (0.41 [0.18–0.65]) for pictorial HWLs on the tobacco packages than text-only compared with smokers. Pictorial HWLs on three parts versus one part elicited higher cognitive reactions and perceived message effectiveness in nonsmokers compared with waterpipe smokers. These findings provide valuable information for policymakers about the potential of implementing HWLs specific to waterpipes to prevent their use among young adults and limit tobacco-related morbidity and mortality in Lebanon. © The Author(s) 2023. Published by Oxford University Press. All rights reserved