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This paper discusses the control problem for a class of wind energy conversion systems (WECS). It first develops a detailed model and then compares among four control algorithms based on conventional and intelligent control theories. A simple PI conventional controller for the exciter loop is carded out by using a first order model. When the system operating points change, the PI controller fails to provide sufficient damping or acceptable performance. Therefore both a fuzzy voltage and a fuzzy power regulators are introduced. Also a conventional adaptive pitch controller is proposed to adjust the pitch angle of the rotor blades in order to maximize the energy capture and reduce the mechanical loads. As an alternative to this controller, a neural network controller is also designed. Using the existing nonlinear wind model and the different control algorithms, the dynamic behavior of the controlled (WECS) is simulated. By selecting convenient wind data, the system characteristics such as its tracking performance, its robustness, and its ability to recover from large disturbances are studied and discussed. Keywords: wind energy, mathematical modeling, PI control, neuro-fuzzy control.

Objectives: Coronavirus disease 2019 (COVID-19) has profoundly impacted residency and fellowship training and education. However, how and to what extent the COVID-19 pandemic in Lebanon compromised the daily involvement of trainees on the clinical and ethical levels is currently unknown, which this study will shed light on., Methods: We conducted a cross-sectional survey (30 questions) targeting medical residents delivering healthcare services in Lebanon. Residents from different specialties were included in the study to assess the effect of the pandemic on their education and the ethical obstacles they faced when dealing with patients., Results: A total of 221 postgraduate medical students participated in our study. Results showed that about half of the residents (52.1%) were only able to do a basic physical examination rather than a full examination as a mandatory requirement in the residency curriculum. The majority (60%) agreed that the doctor-patient relationship is contravened. In addition, almost all residents suffered from fear and emotional distress that affected their education (83.7%)., Conclusion: The findings of this study identify the effect of COVID-19 on residents' training, which affects treatment outcomes and greatly impacts the mental well-being of both healthcare workers and patients., Competing Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Background: Little is known about the acceptance of specific populations of decision makers in Lebanon regarding surrogacy. This study aimed to explore the acceptance and attitude of Lebanese Lawyers and Medical Students regarding surrogacy., Methods: In total 248 medical students and 204 lawyers completed a questionnaire to assess socio-demographic data, attitude toward surrogacy, and three different clinical scenarios to assess patterns of thinking. Finally, we validated a scale to assess the acceptance of surrogacy in these two populations., Results: Concerning medical students, 54.8% reported they were supportive of surrogacy, 35.1% were neutral and 10.1% were against. For lawyers, 52.9% were supportive, 25% were neutral and 22.1% were against. Lawyers were more likely to be against surrogacy (p = 0.001). After conducting a multivariate analysis on the whole studied population to find predictors of acceptance of surrogacy, the best predictors were being single (OR 0.415; 95% CI 0.228, 0.753; p < 0.01), a supportive reported attitude regarding surrogacy (OR 5.464; 95% CI 3.65, 8.13; p < 0.001) and believing that surrogacy is a solution worth discussing in Lebanon (OR 4.186; 95% CI 1.709, 10.256; p < 0.01). Concerning the clinical scenarios, they showed that lawyers were more likely to oppose abortion regardless of the reason (p < 0.01). Also, in a case of gestational surrogacy, lawyers were more likely to give the right to the gestational carrier to keep the baby compared to medical students (p < 0.001)., Conclusion: In conclusion, this study shows that only a minority of medical students and lawyers in Lebanon oppose surrogate pregnancy which warrants exploration of the perspective of other populations of decision makers in Lebanon to better guide legislations., (© 2023. The Author(s).)

While the fighting in the Syrian civil war has mostly stopped, an estimated 5.6 million Syrians remain living in neighboring countries. Of these, an estimated 1.5 million are sheltering in Lebanon. Ongoing efforts by organizations such as UNHCR to support the refugee population are often ineffective in reaching those most in need. According to UNHCR's 2019 Vulnerability Assessment of Syrian Refugees Report (VASyR), only 44% of the Syrian refugee families eligible for multipurpose cash assistance were provided with help, as the others were not captured in the data. In this project, we are investigating the use of non-traditional data, derived from Facebook advertising data, for population level vulnerability assessment. In a nutshell, Facebook provides advertisers with an estimate of how many of its users match certain targeting criteria, e.g., how many Facebook users currently living in Beirut are "living abroad," aged 18-34, speak Arabic, and primarily use an iOS device. We evaluate the use of such audience estimates to describe the spatial variation in the socioeconomic situation of Syrian refugees across Lebanon. Using data from VASyR as ground truth, we find that iOS device usage explains 90% of the out-of-sample variance in poverty across the Lebanese governorates. However, evaluating predictions at a smaller spatial resolution also indicate limits related to sparsity, as Facebook, for privacy reasons, does not provide audience estimates for fewer than 1,000 users. Furthermore, comparing the population distribution by age and gender of Facebook users with that of the Syrian refugees from VASyR suggests an under-representation of Syrian women on the social media platform. This work adds to growing body of literature demonstrating the value of anonymous and aggregate Facebook advertising data for analysing large-scale humanitarian crises and migration events., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Fatehkia, del Villar, Koebe, Letouzé, Lozano, Al Feel, Mrad and Weber.)

Background: Little is known about the attitudes and practices of intensivists working in Lebanon regarding withholding and withdrawing life-sustaining treatments (LSTs). The objectives of the study were to assess the points of view and practices of intensivists in Lebanon along with the opinions of medical, legal and religious leaders regarding withholding withdrawal of life-sustaining treatments in Lebanese intensive care units (ICU)., Methods: A web-based survey was conducted among intensivists working in Lebanese adult ICUs. Interviews were also done with Lebanese medical, legal and religious leaders., Results: Of the 229 survey recipients, 83 intensivists completed it, i.e. a response rate of (36.3%). Most respondents were between 30 and 49 years old (72%), Catholic Christians (60%), anesthesiologists (63%), working in Beirut (47%). Ninety-two percent of them were familiar with the withholding and withdrawal concepts and 80% applied them. Poor prognosis of the acute and chronic disease and futile therapy were the main reasons to consider withholding and withdrawal of treatments. Ninety-five percent of intensivists agreed with the "Principle of Double Effect" (i.e. adding analgesia and or sedation to patients after the withholding/withdrawal decisions in order to prevent their suffering and allow their comfort, even though it might hasten the dying process). The main withheld therapies were vasopressors, respiratory assistance and CPR. Most of the respondents reported the decision was often to always multidisciplinary (92%), involving the family (68%), and the patient (65%), or his advance directives (77%) or his surrogate (81%) and the nurses (78%). The interviewees agreed there was a law governing withholding and withdrawal decisions/practices in Lebanon. Christians and Muslim Sunni leaders declared accepting those practices (withholding or withdrawing LSTs from patients when appropriate)., Conclusion: Withholding and withdrawal of LSTs in the ICU are known concepts among intensivists working in Lebanon and are being practiced. Our results could be used to inform and optimize therapeutic limitation in ICUs in the country.

Phosphogypsum (PG) is an acidic by-product from the phosphate fertilizer industry and it is characterized by a low nutrient availability and the presence of radionuclides and heavy metals which pose a serious problem in its management. Here, we have applied Illumina MiSeq sequencing technology and five bioinformatics pipelines to explore the phylogenetic communities in Tunisian PG. Taking One Codex as a reference method, we present the results of 16S-rDNA-gene-based metataxonomics abundances with four other alternative bioinformatics pipelines (MetaGenome Rapid Annotation using Subsystem Technology (MG-RAST), mothur, MICrobial Community Analysis (MICCA) and Quantitative Insights into Microbial Ecology (QIIME)), when analyzing the Tunisian PG. Importantly, based on 16S rDNA datasets, the functional capabilities of microbial communities of PG were deciphered. They suggested the presence of PG autochthonous bacteria valorizable into (1) removal of radioactive elements and toxic heavy metals, (2) promotion of plant growth, (3) oxidation and (4) reduction of sulfate. These bacteria can be explored further for applications in the bioremediation of by-products, like PG, by different processes., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Surrogate decision making is advocated to protect the vulnerable patient. Family members of patients in intensive care units (ICUs) are prone to develop depressive symptoms which may undermine their decisional capacity. Lebanon is a multicultural country where paternalism still dominates the physician-patient relationship and ethics are far from being the subject of research and studies. This multicenter observational study in the Greater Beirut area attempts to estimate the prevalence of depressive symptoms among surrogates deciding on behalf of ICU patients and to correlate their severity with sociodemographic factors. During the period March-May 2011, direct interviews were conducted and the Patient Health Questionnaire-9 (PHQ-9) was administered to 56 family members who had given consent, regarding therapeutic options, on behalf of ICU patients in seven university hospitals. We looked for relationships, in these surrogates, between severity of depression and age, sex, marital status, level of education, religion and status as the patient's spouse. The prevalence of major depression among surrogates was 61% using a cutoff of 10 on the PHQ-9 scale. Among the surrogates with depression, 15% had untreated moderate-to-severe depression. Severity of depression and suicidal ideation were not related to any of the studied factors. Depressive symptoms are prevalent among family members deciding on behalf of ICU patients, rendering them vulnerable. Appropriate measures should be taken to identify and treat them.