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In this research, we investigate the reinforcement learning-based control strategy for second-order continuous-time multi-agent systems (MASs) subjected to actuator cyberattacks during affine formation maneuvers. In this case, a long-term performance index is created to track the MASs tracking faults using a leader-follower structure. In order to approximate the ideal solution, which is challenging to find for systems vulnerable to cyberattacks during time-varying maneuvers, a critical neural network is used. The distributed control protocol is obtained, and the long-term performance index is minimized, using an actor neural network strengthened with critic signals. The actor-critic neural networks calculate unknown dynamics and the severity of attacks on the MAS actuators. The Nussbaum functions are applied to address this issue since attacks can result in a loss of control direction. The stability of the closed-loop system has been emphasized with the use of a Lyapunov candidate function. The performance of the suggested strategy is then supported by a numerical simulation.

Asthma is the most common chronic medical condition affecting pregnancy. Optimizing asthma management in pregnancy is paramount for the well-being of both the mother and the baby. The primary objectives of this study were to assess patient's knowledge about asthma, the level of asthma care, and fetal and maternal outcomes among pregnant asthmatic women in this wealthy country with tremendous improvement in maternal and fetal health care. The secondary objective was to identify barriers to asthma control. This was a cross-sectional, face-to-face, prospective study of 80 pregnant women with physician-diagnosed asthma. About 56% of patients reported worsening of their asthma control during pregnancy, of which 52.3% felt this worsening in the third trimester. About 65% of patients had uncontrolled asthma during their pregnancy, and inhaler technique was incorrect in 64.4%. Only 38% of patients knew the difference between controller and reliever asthma medications, 12.7% of patients had received written asthma action plan, 17% had a spirometry done in the previous 5 years, and 3.8% had peak expiratory flow meter at home. The main reasons for uncontrolled asthma were lack of knowledge about right asthma medications in 30% and fear of side effects of inhaled corticosteroids in 19% of patients. No financial reason was reported. Significant associations between total number of pregnancies, poor perception of asthma medications, asthma exacerbation during delivery and poor asthma control were observed. Preeclampsia and congenital anomalies occurred at higher rates than previously reported among general population in this country. The tremendous improvements in maternal health care and socioeconomic status do not seem to be a barrier to the globally recognized poor asthma care in pregnancy. Important strategies are much needed. [ABSTRACT FROM AUTHOR]

Atrial myxomata are rare in childhood. A case is described in a boy aged 7 years. The presenting feature was a saddle embolus, requiring immediate surgical intervention. Further investigations showed that a large part of the myxoma remained in the atrium; this portion was successfully removed. This mode of presentation is unusual. The presence of calcification within the myxoma was detectable on intensifier screen examination. The biochemical abnormalities frequently associated with myxomata were not found. The importance of recognizing a myxoma as the cause of a saddle embolus in an otherwise healthy child is emphasized and a number of unusual features of the present case are described. [ABSTRACT FROM PUBLISHER]

The increasing adoption of electric vehicles (EVs) presents both opportunities and challenges for power networks. While EVs have the potential to reduce carbon emissions, accommodating their growing power demand requires careful planning to prevent overloading and mitigate environmental impacts. This paper introduces an integrated hosting capacity model to facilitate higher EV penetration while maintaining environmental standards. In addition to EV charging stations, the model incorporates transmission lines, reactive power compensators, energy storage systems, and thyristor-controlled series compensators to ensure a reliable power supply. The model aims to maximize EV charging station deployment, minimize greenhouse gas emissions, and optimize net present value through hosting capacity strategies. Three hosting capacity plans are proposed to analyze the impact of prioritizing one of these objectives over the others in network configurations. Accurate EV demand forecasting is critical for this model, and a swarm intelligence forecasting algorithm is proposed to explore various forecasting approaches. The model is complex and involves nonlinear multi-objective optimization. To solve it, a new hybrid optimization algorithm is introduced, combining the features of the Marine Predators Algorithm and the Honey Badger Algorithm. Three hybridization schemes-Series Hybrid Scheme, Population Division Scheme, and Switching Strategy Scheme-are developed to address the optimization challenges effectively. The results show that the first and second hybridization schemes are the most effective for solving the EV load forecasting models, with a robustness of at least 90%. In contrast, the robustness of the third scheme reaches only 30% in some models. Simulation studies on the IEEE 9-bus network and the IEEE 30-bus system validate the model's effectiveness in integrating EVs while achieving environmental sustainability objectives. The findings show the superiority of the proposed hybrid schemes in solving the hosting capacity model in terms of finding optimal solutions. However, the third scheme required less computing time than the others, with its convergence time being at least 33.3% shorter., (© 2024. The Author(s).)

Data on acute coronary syndrome (ACS) is lacking in Africa where cases of premature ACS seem to be on the rise. Africa would benefit from an epidemiological assessment of premature ACS to determine its risk factors and management in this demographic to inform guidelines and practice. The European Atherosclerosis Society recognised this urgency and formed a growing network across 11 African countries to create the Lipid Registry of Africa (EAS-LIPRA). This article is based on the EAS-LIPRA protocol and presents the aims, concept and methodological considerations, and the operations and collaborative governance structure of this project. EAS-LIPRA aims to report risk factors and outcomes of premature ACS in Africa to further understand its prevalence and management via collating and pooling multinational prospective data on premature ACS across multiple sites in Africa into a standardised registry. Data will be stratified into subgroups based on country-level income as defined by the World Bank, and within country residence of urban versus rural areas. Valid statistical procedures will be employed to compare and observe trends in the pooled data based on demographics, clinical and laboratory variables, and disparities in its management. Being the first multinational lipid registry in Africa, it is envisaged that the network will expand to other African countries and sites yet to participate, facilitate other epidemiological studies in preventive cardiology, and set a precedent for other developing countries and regions., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier B.V.)

Background/Objectives : Coronary artery bypass graft (CABG) is associated with inflammation and complications, potentially leading to prolonged ICU and hospital stays. Omega-3 PUFA has anti-inflammatory properties, thought to potentially reduce complications in CABG patients. This study aims to systematically review and meta-analyze the impact of perioperative omega-3 PUFA supplementation on total ICU and total hospital stays in CABG patients; Methods : Randomized controlled trials examining the effects of omega-3 PUFA supplementation (IV/oral) on ICU and hospital stays in CABG patients were included. Studies were searched for in PubMed, EMBASE, PsychINFO, CINAHL, and the Cochrane Central Register of Controlled Trial databases, along with hand searching of reference lists. The quality and risk of bias of the included studies were evaluated by two independent reviewers using the revised Cochrane risk-of-bias tool. Meta-analysis was performed using fixed or random effects models according to the level of heterogeneity by mean difference with their 95% confidence intervals; Results : Twelve studies were included in the qualitative analysis and seven in the meta-analysis. Omega-3 PUFA was associated with a significant reduction in days of hospital stay (-0.58 (95% CI -1.13, -0.04)). Subgroup analysis showed that only oral omega-3 PUFA supplementation resulted in a statistically significant reduction in length of hospitalization after subgroup analysis with MD -0.6 (95% CI -1.17, -0.04); Conclusions : This study suggests that perioperative omega-3 PUFA supplementation may reduce the length of hospitalization in CABG patients, especially when administered orally. However, the findings should be interpreted cautiously due to the high level of heterogeneity.

Superior mesenteric artery (SMA) syndrome, also known as Wilkie's syndrome, is a rare condition resulting from compression of the third portion of the duodenum between the aorta and the superior mesenteric artery. When symptomatic, this compression may result in nausea, vomiting, epigastric discomfort, and weight loss, requiring clinical attention and imaging to make the diagnosis. Typically, SMA syndrome presents in young females and is associated with an underlying condition such as anorexia nervosa, cachexia, postoperative development after scoliosis surgery, etc. In this report, we present the case of an atypical delayed presentation of SMA syndrome in an 84-year-old male who had epigastric pain, nausea, intermittent vomiting, and a 30-pound weight loss over two years. SMA syndrome was diagnosed on a computed tomography (CT) scan by a decreased angle between the superior mesenteric artery and abdominal aorta, and treatment with a robotic-assisted strong procedure was performed. The patient was followed postoperatively in the clinic and tolerated the procedure well., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, White et al.)

Phenomenon : The Coping Reservoir Model is a useful theoretical and analytical framework through which to examine student resilience and burnout. This model conceptualizes wellbeing as a reservoir which is filled or drained through students' adaptive and maladaptive coping mechanisms. This dynamic process has the capacity to foster resilience and reduce burnout or the inverse. This study aimed to explore health profession students' coping mechanisms and their experiences of resilience and burnout during the unprecedented COVID-19 pandemic. Approach : Employing the Coping Reservoir Model, qualitative focus groups involving health profession students enrolled at Qatar University were conducted, in October 2020, to solicit their lived experiences of stress and burnout during the pandemic. The Coping Reservoir Model was used to structure the topic guide for the focus group discussion and the Framework Analysis Approach was used in the data analysis. Findings : A total of 43 participants comprised eight focus groups. Health profession students encountered myriad personal, social, and academic challenges during the pandemic which adversely impacted their wellbeing and their capacity for coping. In particular, students reported high levels of stress, internal conflict, and heavy demands on their time and energy. The shift to online learning and uncertainty associated with adapting to online learning and new modes of assessment were exacerbating factors. Students sought to replenish their coping reservoir through engagement in a range of intellectual, social, and health-promoting activities and seeking psychosocial support in their efforts to mitigate these stressors. Insights : Students in this region have traditionally been left to their own devices to deal with stress and burnout during their academic training, wherein the institutions focus exclusively on the delivery of information. This study underscores student needs and potential avenues that health profession educators might implement to better support their students, for instance the development and inclusion of longitudinal wellbeing and mentorship curricula geared to build resilience and reduce burnout. The invaluable contributions of health professionals during the pandemic warrant emphasis, as does an examination of the stress associated with these roles to normalize and justify inclusion of wellbeing and resilience modules within the curriculum. Actively engaging health profession students in university-led volunteer activities during public health crises and campaigns would provide opportunities to replenish their coping reservoirs through social engagement, intellectual stimulation, and consolidating their future professional identities.

Objectives: Tobacco-free campus policies are needed to create environments conducive to prevention or quitting in the Eastern Mediterranean Region (EMR), where the use of various tobacco products is on the rise among university students. The objectives of this study were to assess overall support for a 100% tobacco-free campus policy and its predictors among different stakeholder groups at the largest national university in Qatar and to understand attitudes towards specific policy components., Study Design: A cross-sectional online survey of faculty and students., Methods: We measured sociodemographic variables, tobacco use, and support for components of a 100% tobacco-free campus policy. A total score for support was calculated, and associations with selected predictors were assessed using multivariable linear regression., Results: 413 respondents participated in the survey. A majority of faculty/staff and students (76.6% and 75.5%, respectively) supported the implementation of a 100% tobacco-free campus policy, with a majority supporting extension of the policy beyond cigarettes. Support for other components of the policy varied. Among students, overall support was lower among males and tobacco users and higher among the married. Among faculty and staff, support was lower among Qatari nationals and tobacco users., Conclusion: In the context of a growing tobacco crisis in the EMR, implementing and understanding the impact of tobacco-free campus policies is essential. This paper underscores the importance of addressing diverse stakeholder attitudes and providing empirical evidence to guide policy implementation and evaluation., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Objective: To investigate the association between time spent on screen-based sedentary behavior (SBSB) and depression symptom severity (DSS) among adults with type 2 diabetes., Methods: A cross-sectional study employing secondary data collected by Qatar Biobank (QBB) on 2386 adults with type 2 diabetes aged ≥ 18 years. Self-reported data on DSS measured using the Patient Health Quationnaire-9 and daily time spent on SBSB per week was used., Results: After adjusting for covariates, including physical activity and sleep duration, subjects who spent 2-4 h or > 4 h a day on SBSB watching TV or other devices other than computers during weekdays had increased odds of higher DSS than subjects who spent < 1 h by 44% (95% Confidence interval (CI) 13-83%) and 52% (95% CI 17-96%), respectively. Subjects who spent > 4 h a day on SBSB using computers during weekdays had increased odds of higher DSS by 115% (95% CI 56-196%) than subjects who spent < 1 h. Similar associations were observed between time spent on SBSB using the mentioned devices during weekends and DSS., Conclusion: Increase in time spent on SBSB is independently associated with increased DSS among adults with type 2 diabetes regardless of the equipment used or timing of the week., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.)

Background: Primary care-based studies examining the prevalence of anxiety symptoms severity and associated factors among older adults during the COVID-19 pandemic are scarce. The study aims to determine the prevalence of general anxiety symptoms severity and associated sociodemographic and physical health characteristics, including SARS-CoV-2 infection history, among older adults in primary care in Qatar during the COVID-19 pandemic., Methods: A cross-sectional study was conducted using a random sample of older adults aged 60 years and above (n = 337) from all primary health care centers (n = 28) of Qatar's Primary Health Care Corporation. Participants were interviewed via telephone by family physicians between June and August 2020. General anxiety symptoms severity was assessed using the Generalized Anxiety Disorder 7-item Scale (GAD-7). Descriptive statistics and ordinal regression were used to analyse the data., Results: The mean age of participants was 65 years (ranging from 60 to 89 years), standard deviation = 4.8. About 49.0% and 32.0% of participants were females and of Qatari nationality, respectively. The prevalence of minimal, mild, moderate, and severe general anxiety symptoms was 82.5%, 13.9%, 3.0%, and 0.6%, respectively. Around 33.5%, 63.5%, and 3.0% of participants had unknown, negative, or positive SARS-CoV-2 infection histories, respectively. Females had greater odds of higher levels of anxiety symptoms severity (odds ratio (OR) 2.34; 95% confidence interval (CI) 1.22, 4.50; p = 0.011). As compared to participants with unknown SARS-CoV-2 infection status, those with a negative and positive SARS-CoV-2 infection history had increased odds of higher levels of general anxiety symptoms severity by 2.48 (95% CI 1.17, 5.24; p = 0.017) and 7.21 (95% CI 1.67, 31.25; p = 0.008), respectively. Age, marital status, living arrangements, nationality, and the number of medical conditions had no statistically significant associations with general anxiety symptoms severity., Conclusions: Most older adults experience minimal to mild anxiety symptoms during the COVID-19 pandemic. Female gender and confirmed or suspected SARS-CoV-2 infection history are independent predictors of more severe anxiety symptoms among older adults., (© 2023 Syed, Ziyada, Athar, Khan, Shraim, licensee HBKU Press.)

This study aims to develop a robust control for the quadrotor slung-load system that efficiently follows a reference trajectory. A fractional-order robust sliding mode control has been chosen to control the quadrotor's altitude, position, and attitude. An anti-swing controller was also installed to limit the swing angle of the suspended load. It was created via delayed feedback, in which the quadrotor's position reference trajectory is changed by the difference of the load angles within a specific delayed value. Designing an adaptive FOSMC would control the system when the system uncertainties do not know the bounds. Moreover, the control parameters and the anti-swing controller for the FOSMC can be obtained using some optimization techniques to increase the controllers' accuracy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 ISA. Published by Elsevier Ltd. All rights reserved.)

Background: Coronavirus disease 2019 (COVID-19) is associated with increased risk of cardiovascular mortality. However, little is known about the combined effect of coronary artery disease (CAD) and COVID-19 on mortality. We aimed to investigate the incidence of cardiovascular and all-cause mortality in COVID-19 patients with CAD., Methods: This multicenter retrospective study identified 3,336 COVID-19 patients admitted between March and December 2020. Data points were manually reviewed in the patients' electronic health records. Multivariate logistic regression was used to assess whether CAD and its subtypes were associated with mortality., Results: This study shows that CAD was not an independent predictor of all-cause mortality (odds ratio (OR): 1.512, 95% confidence interval (CI): 0.1529 - 14.95, P = 0.723). However, there was a significant increase in cardiovascular mortality in patients with CAD compared to those without (OR: 6.89, 95% CI: 2.706 - 17.53, P < 0.001). There was no significant difference in all-cause mortality in patients with left main artery and left anterior descending artery disease (OR: 1.29, 95% CI: 0.80 - 2.08, P = 0.29). However, CAD patients with a history of interventions (e.g., coronary stenting or coronary artery bypass graft) showed increased mortality compared to those solely treated by medical management (OR: 1.93, 95% CI: 1.12 - 3.33, P = 0.017)., Conclusions: CAD is associated with a higher incidence of cardiovascular mortality but not all-cause mortality in COVID-19 patients. Overall, this study will help clinicians identify characteristics of COVID-19 patients with increased risk of mortality in the setting of CAD., Competing Interests: The authors report no conflict of interest regarding the content herein., (Copyright 2023, Soney et al.)

Background: The prevalence of burnout and anxiety is constantly increasing among health profession students worldwide. This study evaluates the prevalence of burnout and its relationship to anxiety and empathy during the COVID-19 pandemic among health profession students in the main governmental institution in Doha, Qatar using validated instruments., Methods: A cross-sectional survey of health profession students using validated instruments was employed. The Maslach Burnout Inventory-General Students Survey (MBI-GS(S)) to measure burnout; The Generalized Anxiety Disorder (GAD-7) to measure anxiety; and Interpersonal Reactivity Index (IRI) to measure empathy were utilized. Descriptive statistics and multivariable linear regression were used., Results: Of the 1268 eligible students, 272 (21.5%) completed the online survey. Burnout was found to be prevalent amongst the students. The mean scores for the MBI-GS(S) subscales of emotional exhaustion, cynicism, and professional efficacy were 4.07, 2.63, and 3.97, respectively. Anxiety was found to be a strong predictor for burnout and burnout was positively associated with empathy., Conclusions: Findings from this study demonstrated relationships between health profession students' burnout, anxiety, and empathy. These findings might have an impact on the development of curriculum interventions to enhance student well-being. More burnout awareness and management programs that cater to the specific needs of health profession students are needed. Furthermore, findings of this study may have implications for future educational interventions during times of crisis or how this can be used to improve student experiences in normal times., (© 2023. The Author(s).)

Acne vulgaris is a common neutrophil-driven inflammatory skin disorder in which Cutibacterium acnes (C. acnes) is known to play a key role. For decades, antibiotics have been widely employed to treat acne vulgaris, inevitably resulting in increased bacterial antibiotic resistance. Phage therapy is a promising strategy to combat the growing challenge of antibiotic-resistant bacteria, utilizing viruses that specifically lyse bacteria. Herein, we explore the feasibility of phage therapy against C. acnes. Eight novel phages, isolated in our laboratory, and commonly used antibiotics eradicate 100% of clinically isolated C. acnes strains. Topical phage therapy in a C. acnes-induced acne-like lesions mouse model affords significantly superior clinical and histological scores. Moreover, the decrease in inflammatory response was reflected by the reduced expression of chemokine CXCL2, neutrophil infiltration, and other inflammatory cytokines when compared with the infected-untreated group. Overall, these findings indicate the potential of phage therapy for acne vulgaris as an additional tool to conventional antibiotics., (© 2023. The Author(s).)

COVID-19 results in increased incidence of cardiac arrhythmias, including atrial fibrillation (AF). However, little is known about the combined effect of AF and COVID-19 on patient outcomes. This study aimed to determine if AF, specifically new-onset AF (NOAF), is associated with increased risk of mortality and major adverse cardiovascular events (MACEs) in hospitalized patients with COVID-19. This multicenter retrospective analysis identified 2,732 patients with COVID-19 admitted between March and December 2020. Data points were manually reviewed in the patients' electronic health records. Multivariate logistic regression was used to assess if AF was associated with death or MACE. Patients with AF (6.4%) had an increased risk of mortality (risk ratio 2.249, 95% confidence interval [CI] 1.766 to 2.864, p <0.001) and MACE (risk ratio 1.753, 95% CI 1.473 to 2.085, p <0.001) compared with those with sinus rhythm. Patients with NOAF had an increased risk of mortality compared with those with existing AF (odds ratio 19.30, 95% CI 5.39 to 69.30, p <0.001); the risk of MACE was comparable between NOAF and patients with existing AF (p = 1). AF during hospitalization with COVID-19 is associated with a higher risk of mortality and MACE. NOAF in patients with COVID-19 is associated with a higher risk of mortality but a similar risk of MACE compared with patients with existing AF., Competing Interests: Disclosures The authors have no conflicts of interest to declare., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: To assess the feasibility of using adaptive choice-based conjoint (ACBC) analysis to elicit patients' preferences for pharmacological treatment of osteoarthritis (OA), patients' satisfaction with completing the ACBC questionnaire, and factors associated with questionnaire completion time., Methods: Adult patients aged 18 years and older with a medical diagnosis of OA, experiencing joint pain in the past 12 months, and living in the Northeast of England participated in the study. The participants completed a web-based ACBC questionnaire about their preferences regarding pharmaceutical treatment for OA using a touchscreen laptop independently, and accordingly, the questionnaire completion time was measured. Moreover, the participants completed a pen-and-paper feedback form about their experience in completing the ACBC questionnaire., Results: Twenty participants aged 40 years and older, 65% females, 75% had knee OA, and suffering from OA for more than 5 years participated in the study. About 60% of participants reported completing a computerized questionnaire in the past. About 85% of participants believed that the ACBC task helped them in making decisions regarding their OA medications, and 95% agreed or strongly agreed that they would be happy to complete a similar ACBC questionnaire in the future. The average questionnaire completion time was 16 min (range 10-24 min). The main factors associated with longer questionnaire completion time were older age, never using a computer in the past, and no previous experience in completing a questionnaire., Conclusions: The ACBC analysis is a feasible and efficient method to elicit patients' preferences for pharmacological treatment of OA, which could be used in clinical settings to facilitate shared decision-making and patient-centered care. The ACBC questionnaire completion consumes a significantly longer time for elderly participants, who never used a computer, and never completed any questionnaire previously. Therefore, the contribution of patients and public involvement (PPI) group in the development of the ACBC questionnaire could facilitate participants' understanding and satisfaction with the task. Future research including patients with different chronic conditions may provide more useful information about the efficiency of ACBC analysis in eliciting patients' preferences for osteoarthritis treatment., Competing Interests: The authors declare no conflict of interest.

Objectives: This study aimed to assess the prevalence of ocular manifestations and associated factors in patients on haemodialysis., Methods: A cross-sectional study of patients on haemodialysis from a haemodialysis unit in Nablus, Palestine, was conducted. Medical examination for ocular manifestations (intraocular pressure, cataract, retinal changes and optic neuropathy) was performed using Tono-Pen, portable slit-lamp and indirect ophthalmoscope. Predictor variables were age, gender, smoking, medical comorbidities (diabetes, hypertension, ischaemic heart disease [IHD], peripheral arterial disease [PAD]) and use of antiplatelet or anti-coagulation medications., Results: A total of 191 patients were included in this study. The prevalence of any ocular manifestation in at least one eye was 68%. The most common ocular manifestations were retinal changes (58%) and cataract (41%). The prevalence of non-proliferative diabetic retinopathy (NPDR), proliferative diabetic retinopathy (PDR) and NPDR or PDR was 51%, 16% and 65%. Two patients had PDR in one eye and NPDR in the other, and therefore, they were counted only once making the total for this category 71 rather than 73 patients. An increase in age by one year increased the odds of having cataract by 1.10 (95% confidence interval [CI] = 1.06-1.14). Patients with diabetes had higher odds of having cataract (odds ratio [OR] = 7.43, 95% CI: 3.26-16.95) and any retinal changes (OR = 109.48, 95% CI: 33.85-354.05) than patients without diabetes. Patients with diabetes and IHD or PAD had higher odds of having NPDR than those with diabetes without IHD or PAD (OR = 7.62, 95% CI: 2.07-28.03)., Conclusion: Retinal changes and cataract are common ocular manifestations among patients on haemodialysis. The findings emphasise the importance of periodic screening for ocular problems in this vulnerable population, especially older patients and those with diabetes, to prevent visual impartment and associated disability., Competing Interests: CONFLICTS OF INTEREST The authors declare no conflicts of interest., (© Copyright 2023, Sultan Qaboos University Medical Journal, All Rights Reserved.)

Introduction: Few studies have reported hepatic and cardiac iron overload in patients with end-stage renal disease (ESRD), and the current evidence regarding the prevalence is still scarce., Aim: This review aims to estimate the prevalence of hepatic and/or cardiac iron overload quantified by magnetic resonance imaging (MRI) in patients with ESRD who receive hemodialysis (HD), peritoneal dialysis (PD), or have undergone a kidney transplant., Methods: A systematic review with meta-analysis was conducted and reported in line with PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines. MEDLINE and Embase bibliographic databases were searched using a comprehensive list of controlled vocabulary and keywords to identify relevant studies. All studies reporting the prevalence of hepatic and/or cardiac iron overload quantified by MRI in ESRD patients were considered. The Newcastle-Ottawa scale was used to assess the methodological quality of included studies. To investigate the heterogeneity between studies, random-effect meta-analyses for proportions were used., Results: The review comprised seven studies that included 339 patients. Using meta-analysis, the pooled prevalence of severe and mild to moderate hepatic iron overload quantified by MRI was 0.23 [95% CI: 0.08-0.43] and 0.52 [95% CI: 0.47-0.57], respectively. Only three studies included cardiac iron quantification, and none reported iron overload., Conclusions: This review has revealed a high prevalence of severe hepatic iron overload in patients with ESRD treated by HD. Further studies with a larger sample size are needed to determine the impact of iron overload on vital organs in patients with ESRD and guide future research in this understudied field. Proper use of iron chelation and continuous monitoring will help in the early detection of unsolicited complications; however, the low renal clearance of most iron chelators limits the options for treating iron excess in patients with ESRD., (© 2022 The Authors. Hemodialysis International published by Wiley Periodicals LLC on behalf of International Society for Hemodialysis.)

The use of a maximum power point (MPP) tracking (MPPT) controller is required for photovoltaic (PV) systems to extract maximum power from PV panels. However, under partial shading conditions, the PV cells/panels do not receive uniform insolation due to several power maxima appear on the PV array's P-V characteristic, a global MPP (GMPP) and two or more local MPPs (LMPPs). In this scenerio, conventional MPPT methods, including pertub and observe (P&O) and incremental conductance (INC), fail to differentiate between a GMPP and a LMPP, as they converge on the MPP that makes contact first, which in most cases is one of the LMPPs. This results in considerable energy loss. To address this issue, this paper introduces a new MPPT method based on the Seagull Optimization Algorithm (SOA) to operate PV systems at GMPP with high efficiency. The SOA is a new member of the bio-inspired algorithms. When compared to other evolutionary techniques, it uses fewer operators and modification parameters, which is advantageous when considering the rapid design process. In this paper, the SOA-based MPPT scheme is first proposed and then implemented for an 80 W PV system using the MATLAB/SIMULINK environment. The effectiveness of the SOA based MPPT method is verified by comparing its performance with P& O and PSO (particle swarm optimization) based MPPT methods under different shading scenarios. The results demonstrated that the SOA based MPPT method performs better in terms of tracking accuracy and efficiency., (© 2022. The Author(s).)