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Kawasaki disease (KD) is an acute systemic vasculitis that mostly affects children less than 5years. Occasionally, it may presents with renal involvement of varying severity. In Nigeria and most of Africa, only a few cases of KD have been reported and these were among children within the typical age group. We report an unusual case of Kawasaki disease with renal manifestation in a 14 year old adolescent. Apart from the principal features of KD comprising of high grade fever, non purulent conjunctivitis, polymorphous rash, right sided cervical lymphadenitis and symmetrical desquamative lesions of the digits of the hands and feet; our patient also had renal involvement. The renal manifestations included mild periorbital edema, oliguria, hypertension (140/90mmHg), hematuria(++), proteinuria(++) and elevated serum urea and creatinine (8.3mmol/L and 1.9mg/dl respectively). He was managed with high dose aspirin at 80mg/kg/day. The dose was reduced (5mg/Kg/day) and subsequently stopped after serial echocardiography showed normal coronary arteries. Intravenous immune globuline (IVIG) could not be started due to non availability. Nevertheless, clinical signs resolved, renal function normalised after 6 weeks and echocardiographic picture did not deteriorate. Patient is currently on follow up at the paediatric cardiology clinic of UDUTH, Sokoto, Nigeria.. Conclusion: Kawasaki disease can occur even in older children and renal manifestation may be self limiting. This report highlights the need for high index of suspicion in all cases.

Background: Under nutrition and overweight in children co-exist in developing countries and may persist into adulthood. Interpretation of body mass index (BMI), a useful measure of nutritional status in children requires age related reference standards, many of which were developed from different international sources. It is necessary to determine which of these reference standards is most suitable for use in the assessment of BMI distribution among adolescents in Nigeria. Objective: To determine the prevalence of thinness, overweight and obesity using the World Health Organization (WHO), International Obesity Task Force (IOTF), and Centre for Disease Control (CDC) reference standards and assess their level of agreement amongst adolescents in Sokoto metropolis. Methods: 800 students were selected through multi-stage sampling technique from secondary schools. BMI was classified according to three reference standards (WHO, CDC, IOTF). Data was analysed with SPSS version 22. The level of agreement between the reference standards in diagnosing nutritional status was assessed using Kappa statistics. Level of significance was put at p< 0.05. Results: The prevalence rate of thinness was highest with the IOTF at 22.6% compared to 19.4%, and 19.6% by the WHO and CDC respectively. The prevalence rates of overweight and obesity were highest with the WHO reference standards at 7.0% and 1.3% followed by the IOTF (6.1%and 0.6%) and lowest with the CDC (5.8% and 0.3%). Substantial agreement was observed between WHO and IOTF (Kappa = 0.77), while the level of agreement was 0.68 for IOTF/CDC and 0.64 for WHO/CDC. All agreement statistics were significant (p < 0.001). Conclusion: The WHO and IOTF reference charts may be more suitable for our population.

Context: Pneumonia is the world’s leading infectious killer of children, particularly under- fives. Practical, achievable and affordable key interventions have been identified to reduce morbidity and mortality from Pneumonia. Despite these measures, it still remains a disease that has significant impact on child’s survival. Objectives: To determine the sociodemographic and clinical features of Pneumonia in hospitalized children at Usmanu Danfodiyo University Teaching Hospital (UDUTH), Sokoto, Nigeria. Materials and methods: A retrospective review of records of children admitted for Pneumonia over a 30-month period and relevant information eg. age, gender, symptoms and signs were documented. Results: Of the189 children reviewed, 114(60.3%) were below 1 year of age, males were 108(57.1%) with a M:F ratio of 1.3:1. One hundred and twenty three (65.0%) belonged to the low socio-economic class (SEC) and only 95(50.3%) were fully immunized. Cough and fever were the commonest presenting symptoms while crepitations, chest in drawing and tachypnoea were the commonest signs. Majority 178(94.2%) had Bronchopneumonia while 11(5.8%) had Lobar Pneumonia. 151(79.9%) were discharged, 1(0.5%) absconded and 37(19.6%) died. Cough and fever were seen in more children that died, however it was not significant. Similarly, more children that had crepitations, tachypnoea, chest indrawing and hypoxaemia died, only chest in drawing was significantly associated with mortality (p=0.020). Conclusion: Pneumonia is still a common cause of mortality, socio-demographic and clinical features remain similar to other reports. Despite the availability of preventive measures and treatment guidelines, mortality remains high. We recommend and advocate for equitable access to quality primary health care in order to prevent, diagnose and treat pneumonia.

In this paper, an optimal integrated production - maintenance strategy for a solar power plant, is presented. An optimal maintenance cost model applied to solar power plant with the aim of simultaneously maximizing a plant reliability and minimizing a maintenance cost was developed. The maintenance strategy is a combined priority imperfect/selective maintenance strategy, which selects the priority components for maintenance in order to reduce maintenance downtime. The goal of the paper is to simultaneously determine the optimal energy production and maintenance plan, characterized by the quantity of energy stored and the losses incurred when the energy demand is unmet. The strategy is to minimize the expected total cost of energy production (generation, storage, and shortage) as well as maintenance over a limited time horizon. Thus, determining the energy production economic plan, and the optimal number of maintenances to be performed that yields maximum reliability associated with the cost. A numerical example was presented to validate the developed model using Sokoto solar power plant in Nigeria as the case study.

The major aim of this paper is to explain the data poisoning attacks using label-flipping during the training stage of the electroencephalogram (EEG) signal-based human emotion evaluation systems deploying Machine Learning models from the attackers’ perspective. Human emotion evaluation using EEG signals has consistently attracted a lot of research attention. The identification of human emotional states based on EEG signals is effective to detect potential internal threats caused by insider individuals. Nevertheless, EEG signal-based human emotion evaluation systems have shown several vulnerabilities to data poison attacks. Besides, due to the instability and complexity of the EEG signals, it is challenging to explain and analyze how data poison attacks influence the decision process of EEG signal-based human emotion evaluation systems. In this paper, from the attackers’ side, data poison attacks occurring in the training phases of six different Machine Learning models including Random Forest, Adaptive Boosting (AdaBoost), Extra Trees, XGBoost, Multilayer Perceptron (MLP), and K-Nearest Neighbors (KNN) intrude on the EEG signal-based human emotion evaluation systems using these Machine Learning models. This seeks to reduce the performance of the aforementioned Machine Learning models with regard to the classification task of 4 different human emotions using EEG signals. The findings of the experiments demonstrate that the suggested data poison assaults are model-independently successful, although various models exhibit varying levels of resilience to the attacks. In addition, the data poison attacks on the EEG signal-based human emotion evaluation systems are explained with several Explainable Artificial Intelligence (XAI) methods including Shapley Additive Explanation (SHAP) values, Local Interpretable Model-agnostic Explanations (LIME), and Generated Decision Trees. And the codes of this paper are publicly available on GitHub.

Fractional frequency reuse (FFR) has recently emerged as an efficient inter-cell interference coordination technique for orthogonal frequency division multiple access (OFDMA) based multi-tier cellular networks due to its low complexity, minimal signaling over-head, and coverage improvement. In this work, an intermediary region (IR) at the border of the center region (CR) and edge region (ER) is defined, which prevents severe cross-tier interference and is usually ignored by other schemes. Furthermore, a strategic resource allocation scheme is proposed, which allows macro users in this new region to be served more resources due to their good channel conditions close to the serving base station (BS), while femto users are assigned resource blocks from sub-bands that receive the least net interference from a set of usable sub-bands in any region. We find by analysis and simulation the optimal threshold for IR, which minimizes the cross-tier interference, and show that the femto throughput is also maximized for this threshold. Numerical results show the proposed scheme outperforms other notable schemes in terms of throughput and outage performances.

Cyber-security of modern power systems has captured a significant interest. The vulnerabilities in the cyber infrastructure of the power systems provide an avenue for adversaries to launch cyber attacks. An example of such cyber attacks is False Data Injection Attacks (FDIA). The main contribution of this paper is to analyze the impact of FDIA on the cost of power generation and the physical component of the power systems. Furthermore, We introduce a new FDIA strategy that intends to maximize the cost of power generation. The viability of the attack is shown using simulations on the standard IEEE bus systems using the MATPOWER MATLAB package. We used the genetic algorithm (GA), simulated annealing (SA) algorithm, tabu search (TS), and particle swarm optimization (PSO) to find the suitable attack targets and execute FDIA in the power systems. The proposed FDIA increases the generation cost by up to 15.6%, 45.1%, 60.12%, and 74.02% on the 6-bus, 9-bus, 30-bus, and 118-bus systems, respectively. Finally, a rule-based FDIA detection and prevention mechanism is proposed to mitigate such attacks on power systems.

Background: Rheumatic heart disease (RHD) is the only preventable cardiovascular disease that still causes significant morbidity and mortality in low- and middle-income countries like Nigeria where it is classified as a neglected disease. The inciting agent causes pharyngitis often not properly treated., Aim and Objectives: To study the knowledge and preventive practices of RHD amongst primary healthcare workers who are in contact with larger ratio of populace in order to recommend appropriate interventions., Methodology: A cross-sectional study conducted among health workers in primary health centres in Sokoto metropolis. Multi-stage sampling technique was used to recruit the study participants. A structured questionnaire and focus group discussion guide was used to collect the information. Data was analysed using IBM SPSS version 25., Results: Majority (109/182; 59.8%) had RHD inadequate knowledge of causes, risk factors and treatment of pharyngitis which predisposes to RHD. Only 49 (26.9%) of the respondents knew the name of the causative agent. The knowledge gap was related to length of training and attendance at a training (ꭓ2 = 8.38; P=0.015 & ꭓ2 = 7.92; P=0.004). Majority of the respondents with 168 out of 182 (92.3%) had positive attitude. Practice grading was adequate in only less than half of the respondents (88/182; 48.4%). Male gender and negative attitude were predictors of adequacy of preventive practices (aOR= 0.49; 95% C.I =0.267-0.929; P=0.03 & aOR= 3.87; 95% C.I =1.027-14.586; P=0.046)., Conclusion: The health workers had inadequate knowledge and poor practice on prevention of rheumatic heart disease. It is necessary to upscale information available to them by medical specialists and upgrade their curriculum., Competing Interests: None

Introduction: Ecthyma gangrenosum (EG) is a cutaneous lesion commonly caused by Pseudomonas aeruginosa that involves mainly the lower limbs and gluteal region, seen more in immunosuppressed patients with neutropenia. Cancrum oris (Noma) is a gangrenous necrosis of the face that begins as a gingival ulcer and progresses rapidly to destroy contiguous tissues in malnourished children., Case Presentation: This article reports a case of facial EG which was similar to Noma in a malnourished child: a 16-month old girl with fever, cough, weight loss, watery stool and swelling on right cheek. She was febrile, pale, wasted with bilateral pitting pedal oedema. She had a solitary circumscribed round necrotic lesion, with surrounding hyperaemia on the right malar area which extended to destroy the right ala nasi. No intra-oral rashes but she had left ear discharge. She received blood transfusion, antibiotics, antiseptic wound care and nutritional rehabilitation., Management and Outcome: Swabs of the lesion and ear discharge both revealed Gram-negative bacilli and culture yielded P. aeruginosa . Retroviral, Mantoux and Gene Xpert tests were negative. She had moderate anaemia, normal white blood cell count, and neutropaenia. Parenteral ceftriazone was changed to ciprofloxacin based on sensitivity results and lack of clinical response. The wound healed with residual scarring and partial destruction of right ala nasi., Discussion: Although this patient had facial necrosis to suggest Noma, she did not have initial oral involvement, and clinical features such as Pseudomonas sepsis and neutropaenia suggested EG. Facial necrosis in malnourished children may be due to EG., Competing Interests: The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article.

Background: Congenital heart defects (CHDs) are common birth defects with significant impact on morbidity and mortality. We aimed to compare regional patterns of CHDs in Nigeria using a registry-based approach., Methods: Children with echocardiography-confirmed CHDs at 17 medical centers across the country were enrolled in a pilot National Pediatric Cardiac Registry from January to December 2014., Results: A total of 1,296 children (52.9% male; median age 0.9 years) with CHDs were enrolled. Patients enrolled in Northern Nigeria constituted 34.6% of the study population and were older compared to those enrolled from Southern Nigeria (2.9 ± 3.6 vs 2.4 ± 3.5 years; P = .02). Ventricular septal defects were significantly more prevalent in the North (37.4%) compared with the South (18.5%; P < .0001), while severe CHDs were more prevalent in the South ( P = .004). Of the 208 (16.0%) children who received corrective cardiac intervention, only 43 (20.7%) of them had the intervention done in country. More patients in the South received intervention compared to the North (19.02% vs 10.5%; P < .0001)., Conclusion: This is the first prospective, registry-based, multicenter study of CHDs in Nigerian children. We demonstrate important differences between the Northern and the Southern geographical regions of the country in terms of age at diagnosis, type, and severity of lesion as well as access to cardiac surgery. The findings demonstrate the utility of a national CHDs registry for understanding clinical epidemiology of CHDs in low- and middle-income countries and its potential to serve as a basis for research and planning.