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Experimental and Numerical Assessments of Slab-Column Connections Strengthened Using Bonded Hemp Fiber Fabric Sheets
Get PDFThe replacement of synthetic fibers with natural fibers in concrete has been recently investigated to counter the growing environmental and sustainable issues. Hemp fibers are environmentally friendly and are used in the manufacturing of composite materials. This paper reports on the experimental assessment of using hemp fiber reinforced polymer (HFRP) fabric sheets as an alternative to carbon fiber reinforced polymer (CFRP) sheets to strengthen interior slab-column connections. Small-scale interior slab-column connections were loaded centrally through the column stub up to failure. The main test variables were slab thickness, HFRP sheet width, number of HFRP layers, type of strengthening material (HFRP or CFRP sheets), and HFRP sheet's location relative to the column’s face. Assessment of the strengthening material was based on a comparison of load capacity, mode of failure, load–displacement history, and cracking patterns. The experimental results demonstrated that HFRP strengthening sheets led to improvement in the structural behavior of the slab-column connections depending on the slab thickness, width and configuration for HFRP sheets. Although the HFRP sheets led to lower improvement as compared to the synthetic CFRP sheets, however, the same improvement could be reached by the HFRP sheets if they are applied in larger width or different configurations. A finite-element model was developed using ABAQUS software to predict the behavior of simulated specimens. The numerical findings showed that the models predicted the connection behavior in good agreement with the experimental test results. In addition, an analytical model was calibrated to simulate the behavior of the tested specimens. © 2022, The Author(s)
Cost Effective Analysis of Reducing SO2 Emissions from Power Plants
Get PDFThe aim of this work is to present and assess four alternatives for reducing sulfur dioxide emissions from thermal power plants. The 4 alternatives include using low-sulfur content fuels, installing flue gas desulfurization systems, switching to natural gas, and partially shifting to PV power.
An economic model was established to assess which of the alternatives is the most feasible. The model involves all costs and revenues associated with each of the alternatives. The model was also applied to the Zouk Lebanese power plant.
As there were plenty of uncertainties associated with various parameters, one-way and multiple sensitivity analysis were carried to assess which of the parameters had the biggest effect on the choice of technology to be used.
Results revealed that the natural gas alternative is the most economical for the Lebanese case in most scenarios. This alternative would be more appealing if this natural resource is found in Lebanese offshore territories, saving millions of dollars in purchasing and transporting
A homozygous missense variant in PTPN2 with early-onset Crohn’s disease, growth failure and dysmorphic features in an infant: a case report
No full textCrohn’s disease (CD) is a chronic idiopathic inflammatory bowel condition that can affect any part of the gastrointestinal tract. Several hundred candidate loci or genes including PTPN2 have been reportedly associated with CD. A whole-exome sequencing (WES) was conducted in a 9-year-old Lebanese girl with a CD onset at 13 months and in both her asymptomatic parents. The analysis detected an extremely rare homozygous variant in PTPN2: c.359C>T, p.(Ser120Leu) in the patient, while both her parents were heterozygous. This variant, located in the protein tyrosine phosphatase (PTP) domain within a highly conserved amino acid, is classified as VUS according to the American College of Medical Genetics (ACMG) criteria. To evaluate the hypothetical functional consequences of the identified variant, a quantitative expression analysis of PTPN2 was performed in blood tissues of the patient, her parents, and two healthy controls. PTPN2 expression was not noted in the patient compared to her parents and the normal controls, suggesting a functional PTPN2 impairment caused by c.359C>T. This variant c.359C>T, p.(Ser120Leu) in PTPN2 has never been previously described in the literature. Our report suggests an association of PTPN2: c.359C>T with early-onset CD. © 2023, Indian Academy of Sciences
Frequency and mutational spectrum of PIK3CA gene mutations in breast cancer patients: Largest and first report from Lebanon
Get PDFThe PIK3CA pathway is one of the most frequently altered pathways in human cancers, especially in breast cancer with approximately 40% of HR+/HER2– advanced breast cancer cases exhibiting mutations in the PIK3CA gene. While the mutations can occur across the entire gene, the most common are observed in exon 9 corresponding to the helical domain, and in exon 20 encompassing the kinase domain. This study constitutes the first attempt at determining the frequency and mutational spectrum in Lebanese breast cancer patients. For this purpose, DNA samples from 280 breast cancer patients from across Lebanon were screened for PIK3CA mutations using the Therascreen® PIK3CA RGQ Real-time PCR assay. In line with previous reports, 38.57% of cases were positive for at least one PIK3CA mutation, among which approximately 59% were in exon 9 and 37% in exon 20. However, PIK3CA mutations are breast cancer are heterogeneous whereby 20% of known PIK3CA mutants might not be detected by compact PCR based assays. Thus, the adoption of comprehensive Next Generation Sequencing based panels to decipher the complete clinical, molecular and immunohistochemical profile of breast cancer tumor requires further investigation. © 2023 Elsevier B.V
Non-overweight depressed patients who respond to antidepressant treatment have a higher risk of later metabolic syndrome: findings from the METADAP cohort
Get PDFBackground Major depressive disorder (MDD) is a complex disorder with a significant public health burden. Depression remission is often associated with weight gain, a major risk factor for metabolic syndrome (MetS). The primary objective of our study was to assess prospectively the impact of response to antidepressant treatment on developing MetS in a sample of MDD patients with a current major depressive episode (MDE) and who are newly initiating their treatment. Methods In the 6-month prospective METADAP cohort, non-overweight patients, body mass index <25 kg/m2, with MDD and a current MDE were assessed for treatment response after 3 months of treatment, and incidence of MetS after 3 and 6 months of treatment. Outcome variables were MetS, number of MetS criteria, and each MetS criterion (high waist circumference, high blood pressure, high triglyceridemia, low high-density lipoprotein-cholesterolemia, and high fasting plasma glucose). Results In total, 98/169 patients (58%) responded to treatment after 3 months. A total of 2.7% (1/38) developed MetS out of which 12.7% (10/79) (p value < 0.001) had responded to treatment after 3 months. The fixed-effect regression models showed that those who responded to treatment after 3 months of follow-up had an 8.6 times higher odds of developing MetS (odds ratio = 8.58, 95% confidence interval 3.89-18.93, p value < 0.001). Conclusion Compared to non-responders, non-overweight patients who responded to treatment after 3 months of antidepressant treatment had a significantly higher risk of developing MetS during the 6 months of treatment. Psychiatrists and nurses should closely monitor the metabolic profile of their patients, especially those who respond to treatment. © The Author(s), 2023
Experiences of stigma, mental health, and coping strategies in Lebanon among Lebanese and displaced Syrian men who have sex with men: A qualitative study
Get PDFBackground: In Lebanon, men who have sex with men (MSM) face high rates of stigma, discrimination, and violence. Minority stress, or the unique stressors related to anti-MSM stigma and discrimination, negatively impacts the mental health of MSM. These stressors are heightened for those with intersectional minority identities such as displaced Syrian MSM in Lebanon. Methods: In this qualitative study conducted in 2020–21, part of a larger study focused on the mental and sexual health risks among MSM, we collected qualitative data from Lebanese and displaced Syrian MSM living in Lebanon and analyzed reports of their experiences with stigma, mental health, and coping strategies. We conducted semi-structured, in-depth interviews with 12 displaced Syrian MSM and 13 Lebanese MSM. Results: Our findings highlight how MSM in Lebanon navigate stigma and the mental health risks that result. Common stressors among Lebanese and displaced Syrian MSM were related to finances, sexual orientation discrimination, and social isolation. Comparing the two groups, we found that stressors specific to displaced Syrian MSM were related to adverse childhood experiences, recent exposure to the Syrian war, displacement, and discrimination in Lebanon based on their intersectional identities as MSM and Syrians. For Lebanese participants, the most common stigma coping strategies were avoidance, drinking alcohol, using drugs, or having sex. As for displaced Syrian MSM, the most common stigma coping strategy was seeking the freely available mental health services offered to them through non-governmental organizations. Conclusion: Our findings suggest that increased targeted mental health and social support interventions, informed by the unique experiences of Lebanese and displaced Syrian MSM, are highly needed to improve the coping and mental health resources of all MSM in Lebanon. © 202
Sedation as an alternative anesthetic technique for frail patients in transurethral resection of the prostate
Get PDFBackground: Transurethral resection of the prostate (TURP) under Monitored Anesthesia Care MAC/Sedation (macTURP), as compared with TURP under general (genTURP) or spinal (spTURP) anesthesia, is a safer and infrequently used technique reserved for high-risk patients. Objectives: The aim of this study is to compare 30-day postoperative outcomes of TURP using the three types of anesthesia techniques. Design and methods: The American College of Surgeons National Surgical Quality Improvement Program database was queried for patients who underwent TURP between 2008 and 2019. Demographics, lab values, medical history, and 30-day outcomes were compared. Univariate and multivariate regression models for postoperative complications were constructed. A propensity score–matched analysis was then performed for genTURP and macTURP and for spTURP and macTURP as a sensitivity analysis. Results: A total of 53,182 patients underwent TURP. Older patients (>80) with diabetes requiring insulin (7.9%), leukocytosis (7.4%), history of chronic obstructive pulmonary disease (COPD) (7.8%), dyspnea (7.2%), and of ASA > 2 (58.8%) were more likely to undergo macTURP as compared with genTURP (p < 0.013). SpTURP showed lower rates of urinary tract infection (UTI) [odds ratio (OR) = 0.869] as compared with genTURP (p = 0.049), whereas macTURP showed higher rates of major adverse cardiovascular events (OR = 2.179) as compared with genTURP (p = 0.005). All other postoperative complications showed similar rates between the three procedures. The propensity-matched cohorts demonstrated that no differences in postoperative complication rates were noted between macTURP and genTURP and between macTURP and spTURP. Conclusion: MacTURP was found to be feasible with a good safety profile as compared with genTURP and spTURP. MacTURP could be used in elderly, frail, and co-morbid patients with a similar safety profile as compared with more invasive anesthetic techniques. © The Author(s), 2023
A new MILP model and fast heuristics for the variable-sized bin packing problem with time windows
Get PDFVariable-Sized Bin Packing Problem with Time Windows (VSBPPTW) is a variant of the classical bin packing problem in which several types of bins with different sizes and costs are available, and the total cost of bins used to pack all items is minimized. Additionally, a time window is defined for each item, and the set of items packed into each bin must be time-compatible, i.e., the items in a bin must have at least one common time point within their time windows. We propose a new mixed-integer linear programming (MILP) model for VSBPPTW that (i) ensures time-compatibility by filling each bin with items from one maximal time-compatible set only and (ii) uses a compressed network flow formulation to represent the packing of items into bins under each maximal time-compatible set. New fast heuristics for VSBPPTW are also proposed to warm-start the MILP solver. Computational experiments are carried out on two sets of benchmark problem instances from the literature. We show that the new fast heuristics obtain on average much better solutions than the previously proposed fast heuristic, and the new MILP model greatly outperforms the previously proposed MILP model. While the previously proposed MILP model solves to optimality only 13% of the problem instances in the first set and none in the second, the new MILP model solves to optimality over 70% problem instances in both sets. © 2022 Elsevier Lt
Enhancing Essential Grains Yield for Sustainable Food Security and Bio-Safe Agriculture through Latest Innovative Approaches
Get PDFA key concern in agriculture is how to feed the expanding population and safeguard the environment from the ill effects of climate change. To feed a growing global population, food production and security are significant problems, as food output may need to double by 2050. Thus, more innovative and effective approaches for increasing agricultural productivity (hence, food production) are required to meet the rising demand for food. The world’s most widely cultivated grains include corn, wheat, and rice, which serve as the foundation for basic foods. This review focuses on some of the key most up-to-date approaches that boost wheat, rice, corn, barley, and oat yields with insight into how molecular technology and genetics may raise the production and resource-efficient use of these important grains. Although red light management and genetic manipulation show maximal grain yield enhancement, other covered strategies including bacterial-nutrient management, solar brightening, facing abiotic stress through innovative agricultural systems, fertilizer management, harmful gas emissions reduction, photosynthesis enhancement, stress tolerance, disease resistance, and varietal improvement also enhance grain production and increase plant resistance to harmful environmental circumstances. This study also discusses the potential challenges of the addressed approaches and possible future perspectives. © 2023 by the authors
A suggested protocol for the endocrine postoperative management of patients undergoing pituitary surgery
Get PDFPurpose: Endocrine disorders are the most frequent postoperative complications in patients undergoing pituitary surgery. Given the absence of recent guidelines on the postoperative care following pituitary surgery, this article summarizes the available evidence on the topic. Method: We conducted a systematic search of PubMed up to 2021 and updated the search in December 2022. We retrieved 119 articles and included 53 full-text papers. Results: The early postoperative care consists of the assessment for cortisol deficiency and diabetes insipidus (DI). Experts suggest that all patients should receive a glucocorticoid (GC) stress dose followed by a rapid taper. The decision for GC replacement after discharge depends on the morning plasma cortisol level on day 3 after surgery. Experts suggest that patients with a morning plasma cortisol 18 mcg/dL, the patient can be discharged safely without GC, as suggested by observational studies. Postoperative care also includes a close monitoring of water balance. If DI develops, desmopressin is used only in case of uncomfortable polyuria or hypernatremia. The assessment of other hormones is indicated at 3 months postoperatively and beyond. Conclusion: The evaluation and treatment of patients following pituitary surgery are based on expert opinion and a few observational studies. Further research is needed to provide additional evidence on the most appropriate approach. © 2023 Elsevier Masson SA