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Publisher Copyright: © 2021, International Journal of Renewable Energy Research. All Rights Reserved. Copyright: Copyright 2021 Elsevier B.V., All rights reserved. Photovoltaic (PV) systems are taking a leading role as a solar-based renewable energy source (RES) because of their unique advantages. This trend is being increased in the field of Seawater desalination. This paper presents a study on the Seawater Desalination Plant (SWDP) located in Egypt feeding from the utility network. The main challenge in such a nonlinear system with a high level of variability is the optimum sizing of the SWDP with the proposed whole solar-powered while keeping good dynamic performance. In this article, a solid electrical load analysis is presented to assess the optimal design of SWDP fed by the PV system. Moreover, optimal maximum power point tracking controllers (MPPTCs) are developed to enhance the dynamic performance of SWDP fed by the PV system. To accomplish this study, a real grid connected seawater desalination plant located in Egypt is implemented. The selected SWDP is producing 700 m3/day. The real experimental data of the plant were extracted through daily readings of electricity consumption and water production meters. This experimental data is then introduced to the HOMER program to suggest the optimal components of the PV system based on the minimum net present cost. The developed power plant consists of a Photovoltaic (PV) array, DC/AC converter, load and grid. Also, to tackle the challenge of the low conversion efficiency of the PV system, three MPPTCs are investigated to improve the dynamic performance of the proposed SWDP fed by the PV system. Incremental Conductance in conjunction with three artificial intelligence (AI) optimization techniques (Particle Swarm Optimization, Grey Wolf Optimization (GWO) and Harris Hawks Optimization) is developed for the assessment of the dynamic performance of the presented SWDP fed by PV. The system was constructed, modeled and simulated through MATLAB/SIMULINK. The attained results of the three methods are promising in extracting the maximum power with minimum error from the PV system while improving the performance of SWDP. The obtained simulation, as well as experimental results, proves the efficacy of the suggested optimal design strategy.

Background/Aim: The absolute risk of death due to coronary artery disease (CAD) is two to five times higher in patients with diabetes than in those without diabetes regardless of the cholesterol concentration, and females with diabetes have the worst prognosis. The aim of the current study was to investigate the angiographic severity and extent of CAD in patients with Type 2 diabetes mellitus, compared with nondiabetic patients. Patients and Methods: A hospital-based retrospective cross-sectional study was performed on 340 patients who were diagnosed with CAD. The two groups were matched for age, gender, and other major risk factors. Data collected include demographic data, distribution, and extent of coronary artery involvement. Results: Three hundred and forty patients were included in the study, 175 of them (51.4%) were diabetics, and 165 (48.5%) were nondiabetics, comparing coronary angiographic results of both groups: One hundred and twenty-six patients (73%) of the diabetic patients have multivessel diseased (P = 0.003), 49 patients (27%) have a single-vessel diseased and none of them have a normal coronaries (0%). While for the nondiabetic patients 82 (50%) of them have a multivessel diseased, 63 patients (38%) have a single-vessel diseased, and 20 patients (12%) have normal coronaries. Conclusion: Multivessel disease with diffuse lesion is more prevalent among diabetic Libyan patients compared with nondiabetics. The affected vessels in diabetic patients are diffusely diseased more than nondiabetic.

Introduction: There are no data so far regarding the frequency and outcome of the different types of atrial fibrillation (AF) in the clinical setting for Libyan patients. Furthermore, it is unknown whether the actual clinical management and therapy of AF in Libya conform to the international guidelines. The aim of this study was to determine the frequency, demographic, and clinical characteristics of AF patients. Patients and Methods: Three hundred patients attending the outpatient clinic and cardiology department at Benghazi Medical Center and National Cardiac Center between May 2020 and October 2020 were included. Patients' data were obtained through medical records using the chart review. Patients were categorized into a clinical type of AF, based on the physician's perception of the AF at the time of presentation. Results: Three hundred patients with an established diagnosis of AF were enrolled, including 210 (70%) females and 90 (30%) males. The mean age at the time of diagnosis was 49.5 ± 21.5 years, with an age range of 29–79 years. Of them 139 (46.3%) were diagnosed as permanent AF, 132 (44%) paroxysmal AF, while new-onset AF was diagnosed in 29 (9.7%). The three clinical categories of AF were enrolled under the care of both cardiologists and internal medicine physicians, but permanent AF patients were more often enrolled under the care of a cardiologist. Patients with permanent AF were older compared with those with paroxysmal subtype (61.8 ± 9 and 50.1 ± 12, respectively), with significant female predominance (P = 0.03), and more often had coronary artery disease (CAD), valvular heart disease, and a previous stroke/TIA (P = 0.01, P = 0.124, and P = 0.002, respectively). Diabetes was the most prevalent associated medical condition, followed by hypertension and hyperlipidemia. CAD was diagnosed among 122 patients. Of permanent AF patients, 28 patients (20.1%) previously suffered from a stroke, mostly TIA, in contrast to 14 patients (10.6%) of the other AF patients. Conclusion: Our AF patients were characterized by an unfavorable cardiovascular risk profile. We recognize a lower rate of oral anticoagulation prescription, which needs further evaluation.

Down syndrome (DS) is the most common autosomal chromosome anomaly. DS is frequently associated with congenital heart disease (CHD). Patients with DS have 40–60% chance of having CHD. It means that CHD in DS is not only due to trisomy 21 and there are some other genetic factors underlying CHD in DS children. In this study, a total of 240 DNA samples from patients were analyzed including 100 patients with CHD only, 110 patients having CHD along with DS and 30 patients with isolated DS. A cardiovascular gene panel consisting of probes for 406 genes was used to screen DNA samples of all 240 patients for mutation identification. All variants were annotated and common variants were obtained. Briefly, 28 common variants (variants common in two or more than two individuals) were obtained in a group of samples containing DNA from DS patients having CHD as well, 63 variants were found to be unique to DS group of samples and 73 variants have been identified in patients with CHD only. In order to identify genomic variations determining the risk for CHD in DS, only those variants present in DS-CHD group and absent in isolated CHD and/or isolated DS group were considered for further analysis. Variants specific to DS-CHD group were further evaluated based on expression and function data and pathogenicity of the variant of interest. We have implicated mutations in GATA3, KCNH2, ENG, FLNA, and GUSB genes as an underlying risk factor for CHD in DS patients.