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In the present study, numerical simulation for a two-dimensional NACA0005 is performed for angles of attack ${\alpha } = {0^{\circ }-15^{\circ }}$ . The Reynolds numbers 1000, 2000 and 5000 are considered. Simulations show that the flow fields can be classified due to characteristics of vortex shedding based on Reynolds number and angle of attack. Furthermore, this study reveals that in the case of thinner airfoils, several modes (Mode I, Mode II, Mode III) are present at the same angle of attack for varying Reynolds number. Maximum lift to drag ratio is found at Reynolds number 5000 and angle of attack 6° as well as gradual stall is observed. Onset of oscillations to determine critical angles of attack is reported for NACA0005 with the dominant frequencies. A subcategory of mode III termed as mode IIIa/c, and recently reported mode 4i is also observed in present study. A new mode termed as k-mode is discovered for higher angles of attack at Re = 5000. In addition, numerical simulations of two-dimensional periodic flows around NACA0005 profile at Reynolds number Re = 5000 demonstrate that unsteady periodic flows reach different saturation states at angles of attack of $10^{\circ }-15^{\circ }$ . The coexisting periodic states and period-doubling (with higher and lower intensities) in this range indicate that the wake undergoes substantial changes from the Von-Kármán vortex street.

This paper investigates the formation control of multiple heterogeneous quadrotor unmanned aerial vehicles (UAVs). The research focuses on developing a distributed robust formation control strategy to effectively manage the translational and attitude motions of the UAVs utilizing an active virtual leader. The communication of each agent in a connected environment is represented by a directed graph. To align with real applications, only a minimum of one agent is required to connect with the leader. The challenge associated with controlling systems is more complicated by the inherent heterogeneity of UAVs, characterized by variations in their model parameters and the presence of external disturbances in the system dynamics. A robust term is proposed to handle time-varying disturbances added to the closed-loop systems. A comprehensive mathematical proof and numerical illustrations are provided to validate the efficacy of the proposed formation control strategy.

BACKGROUND: Tetralogy of Fallot represents 7–10% of all cases of congenital heart disease, as it occurs in approximately 0.5 per 1,000 live births and is the second most common form of complex congenital heart disease. Advances in diagnosis, surgical techniques, and postoperative treatment have led to an increasing number of patients reaching adulthood, with a dramatic increase in the survival rate to almost 90% at 30 years, thereby creating a need for long-term monitoring of certain anatomic parameters to identify complications in a timely manner. This study aimed to investigate the frequency of computed tomography detected complications after radical correction of Tetralogy of Fallot in pediatric patients. AIM: to identify markers between the most frequency computed tomography detected complications after repair of Tetralogy of Fallot in pediatric patients. MATERIALS AND METHODS: A retrospective analysis was conducted on 613 patients with Tetralogy of Fallot from October 2011 to June 2020. The study included a total of 116 patients (69 men and 47 women) who experienced complications after a repair of Tetralogy of Fallot, as identified by computed tomography. At the time of repair of Tetralogy of Fallot, the patient’s average age ranged from 10 to 36 months (mean: 12 months), average body weight was 21 kg, average height was 105.4 cm, and average body surface area was 0.74 m2. The patients’ median age at the time of the computed tomography examination was 17.5 years (age range: 7–36 years). RESULTS: Among the 116 patients who exhibited complications after an repair of Tetralogy of Fallot, 49 had a pulmonary artery stenosis, 92 had a pulmonary artery branch stenosis (56 of them of the left main pulmonary artery branch, and 36 of them of the right main pulmonary artery branch), 8 had a right ventricular outflow tract stenosis, 32 had a ventricular septal defect, 1 had a shunt thrombosis, 12 had a postoperative deformation of the pulmonary artery, 10 exhibited a marked right ventricular dilatation, 2 had an right ventricular outflow tract aneurysm, and 6 suffered from conduit calcification and stenosis. Moreover, patients with left main pulmonary artery branch stenosis had a 6.5 times greater chance of developing an right main pulmonary artery branch stenosis in (p 0.001). CONCLUSION: The most frequently computed tomography detected complications after a repair of Tetralogy of Fallot were pulmonary artery stenosis and pulmonary artery branch stenosis. Patients with pulmonary artery stenosis and pulmonary artery branch stenosis exhibit no significant differences in terms of age, anthropometric parameters (height, weight, and body surface area), and gender distribution in the presence or absence of different stenosis types (pulmonary artery, right main pulmonary artery branch, or left main pulmonary artery branch). However, an right main pulmonary artery branch stenosis increases the chances of developing an left main pulmonary artery branch stenosis.

Abstract Stainless steel (SS) is widely employed in industrial applications that demand superior corrosion resistance. Modeling its corrosion behavior in common structural and various operational scenarios is beneficial to provide wall-thickness (WT) information, thus leading to a predictive asset integrity regime. In this spirit, an approach to model the corrosion behavior of SS 316L using artificial neural networks (ANNs) is developed, whereby saline water at different concentrations is flown through an elbow structure at different flow rates and salt concentrations. Voltage, current, and temperature data are recorded hourly using electric field mapping (EFM) pins installed on the elbow surface, which serve as training data for the ANNs. The performance of corrosion modeling is verified by comparing the predicted WT with actual measurements obtained from experimental tests. The results show the exceptional performance of the proposed single ANN model to predict WT. The error is calculated by comparing the estimated WT and actual measurement recorded, where the maximum error for each setting is range from 0.5363 to $$0.7535\%$$ 0.7535 % . RMSE and MAE values of each pin in every setting are also computed such that the maximum values of RMSE and MAE are 0.0271 and 0.0266, respectively. Moreover, a concise account of the observed scale formation is also reported. This comprehensive study contributes to a better understanding of SS 316L corrosion and offers valuable insights for developing efficient strategies to prevent corrosion in industrial environments. By accurately predicting WT loss using ANNs, this approach enables proactive maintenance planning, minimizing the risk of structural failures and ensuring the extended sustainability of industrial assets.

The usage of multicopter unmanned aerial vehicles (UAVs) has increased for various military and civilian purposes. The choice of propulsion system of such a vehicle is crucial to fulfill the intended mission requirements. The present study focuses on evaluating the efficiency of propulsion system by experimenting with different motor, propeller and battery combinations. The connection between the electronic speed controller (ESC) signal, current, power, thrust and torque in relation to propeller size is determined. It is observed that regardless of battery capacity or motor type, the thrust and torque produced for a given motor speed (RPM) for a specified propeller are similar. The higher capacity battery with 6000 mAh, denoted as B2 battery, consumes less current and can attain higher motor speed to produce the required thrust force than a lower capacity battery with 3300 mAh, denoted as B1 battery. The most efficient propeller, 12 inches in diameter (P4 propeller), is observed to achieve efficiency levels of 12.9 % for the B1 battery and 11.4 % for the B2 battery. Similarly, the most efficient motor, 700 KV motor (M1), is determined to exhibit efficiency of 64.29 % when coupled with the B1 battery and 62.01 % when coupled with the B2 battery. It is identified that using the B2 battery results in an increased payload capacity of 5.82 N, compared to 2.02 N with the B1 battery. Furthermore, when considering both scenarios with and without payload, greater endurance is observed when B2 battery is used as opposed to the B1 battery.

The discrete control problem of vertical take-off and landing unmanned aerial vehicle (VTOL UAV) in the presence of time-varying uncertain disturbances is developed in this paper. The complexity of control problem is managed by dividing the dynamical model into two subsystems i.e. translational dynamics and rotational dynamics, where each subsystem is composed of three states. A discrete-time quasi-sliding mode control (DTQSMC) is extended to maintain the trajectory tracking control by proposing a new-reaching law for VTOL UAV. A robust controller is designed to handle unknown time-varying disturbances acting upon the translational and rotational dynamics. Moreover, the proposed controller is designed to reduce the chattering issue that commonly appears in conventional sliding mode control (SMC). Rigorous mathematical proof is presented to analyze the stability of the entire closed-loop system. The performance of this design is demonstrated with numerous numerical analyses and simulations.

This study examined the performance of random forest (RF), support vector machine (SVM) and adaptive boosting (AB) machine learning models used to estimate daily potato crop evapotranspiration adjusted (ETc-adj) under full irrigation (I100), 50% of full irrigation supply (I50) and rainfed cultivation (I0). Five scenarios of weather, crop and soil data availability were considered: (S1) reference evapotranspiration and precipitation, (S2) S1 and crop coefficient, (S3) S2, the fraction of total available water and root depth, (S4) S2 and total soil available water, and (S5) S3 and total soil available water. The performance of machine learning models was compared with the standard FAO56 calculation procedure. The most accurate ETc-adj estimates were observed with AB4 for I100, RF3 for I50 and AB5 for I0 with coefficients of determination (R2) of 0.992, 0.816 and 0.922, slopes of 1.004, 0.999 and 0.972, modelling efficiencies (EF) of 0.992, 0.815 and 0.917, mean absolute errors (MAE) of 0.125, 0.405 and 0.241 mm day−1, root mean square errors (RMSE) of 0.171, 0.579 and 0.359 mm day−1 and mean squared errors (MSE) of 0.029, 0.335 and 0.129 mm day−1, respectively. The AB model is suggested for ETc-adj prediction under I100 and I0 conditions, while the RF model is recommended under the I50 condition.

The scale at which the SARS-CoV-2/COVID-19 pandemic has spread remains enormous. Provided the genetic makeup of the virus and humans is readily available, the quest for knowing the mechanism and epidemiology continues to prevail across the entire scientific community. Several aspects, including immunology, molecular biology, and host-pathogen interaction, are continuously being dug into for preparing the human race for future pandemics. The exact reasons for vast differences in symptoms, pathophysiological implications of COVID-infections, and mortality differences remain elusive. Hence, researchers are also looking beyond traditional genomics, proteomics, and transcriptomics approach, especially entrusting the environmental regulation of the genetic landscape of COVID–human interactions. In line with these questions lies a critical process called epigenetics. The epigenetic perturbations in both host and parasites are a matter of great interest to unravel the disparities in COVID-19 mortalities and pathology. This review provides a deeper insight into current research on the epigenetic landscape of SARS-CoV-2 infection in humans and potential targets for augmenting the ongoing investigation. It also explores the potential targets, pathways, and networks associated with the epigenetic regulation of processes involved in SARS-CoV-2 pathology.

Due to water scarcity and harsh climate, Saudi Arabia and its neighboring countries rely heavily on fresh food imports from distant lands and have higher per capita expenditures on vegetable imports compared with USA and China. Aquaponics can supply fresh food throughout the year and may complement conventional agriculture in Saudi Arabia to help the objectives and policies defined by the government for food and water security. In this spirit, an Aquaponics farm is being constructed in the desert-coast climate to study the feasibility. A detailed SWOT analysis is performed for a commercial farm which reveals that the advantages of Aquaponics in the Saudi market outweigh the weaknesses. Preliminary experiences show that such ventures require high capital costs and synergistic collaboration of engineering, agriculture, business, and geology.

Insulators are considered one of the most significant parts of power systems which can affect the overall performance of high-voltage (HV) transmission lines and substations. High-voltage (HV) insulators are critical for the successful operation of HV overhead transmission lines, and a failure in any insulator due to contamination can lead to flashover voltage, which will cause a power outage. However, the electrical performance of HV insulators is highly environment sensitive. The main cause of these flashovers in the industrial, agricultural, desert, and coastal areas, is the insulator contamination caused by unfavorable climatic conditions such as dew, fog, or rain. Therefore, the purpose of this work is to review the different methods adopted to identify the contamination level on high-voltage insulators. Several methods have been developed to observe and measure the contamination level on HV insulators, such as leakage current, partial disgorgement, and images with the help of different techniques. Various techniques have been discussed alongside their advantages and disadvantages on the basis of the published research work in the last decade. The major high-voltage insulator contamination level classification techniques discussed include machine learning, fuzzy logic, neuro–fuzzy interface, detrended fluctuation analysis (DFA), and other methods. The contamination level data will aid the scheduling of the extensive and costly substation insulator, and live line washing performed using high-pressured water. As a result, considerable benefits in terms of improved power system reliability and maintenance cost savings will be realized. This paper provides an overview of the different signal processing and machine-learning methods adopted to identify the contamination level on high-voltage insulators. Various methods are studied, and the advantages and disadvantages of each method are discussed. The comprehensive review of the islanding methods will provide power utilities and researchers with a reference and guideline to select the best method to be used for contamination level identification based on their effectiveness and economic feasibility.

Purpose: To assess the antioxidant and antineoplastic effects of Hibiscus sabdariffa Linn. on oral squamous cell carcinoma cells. Materials and Methods: Human squamous cell carcinoma HSCC cells were tested for cytotoxicity by a methanol extract of Hibiscus sabdariffa (MEHSP). After 24, 48, and 72 h, the MTT assay and Trypan blue exclusion test were used to determine cell survival and death. 2, 2-diphenyl-1-picrylhydrazyl (DPPH), DNA Protection Assay (DPA), and ferric reducing antioxidant power assay (FRAPA) measured the antioxidant activity of MEHSP. Results: The antioxidant activity (%) ranged from 47.92-82.24 in the DPPH test, 11.61-73.65 in the DPA, and 4.97-52.09 in the FRAPA. The HSCC in-vitro cytotoxicity assay showed dose- and time-dependent cell viability. MEHSP at 5 μg/ml inhibited viable cells, while increasing MEHSP doses decreased cell viability. The Trypan blue exclusion test showed that MEHSP significantly reduced cell viability at 24, 48, and 72 h. Conclusion:Hibiscus sabdariffa contains antioxidant and HSCC-cytotoxic properties. [ABSTRACT FROM AUTHOR]

The current research was conducted to investigate the impact of injecting hatching eggs with varying levels of plasma of local chickens. In this investigation, 180 fertile eggs were divided into three groups. The first group (P0) is the control, while the eggs in both the second(P1) and third groups (P2) were injected with 50 or 100 μl of local chicken blood plasma, respectively. The eggs were injected at the first day of incubation (0 day). After 21 days, the fertility, hatching characteristics, immunological, and physiological properties of the hatched chicks were evaluated. The results revealed no significant variations in the hatching percentage, weight of the hatched chicks, and their relative weight. the physiological blood traits revealed that the third treatment showed a significant rise in red blood cells, hematocrit value, and hemoglobin with a significant decrease in white blood cells. The third treatment showed a considerable rise in the total protein concentration due to the higher globulin protein level, which is vital for immunity, and improved antioxidant glutathione levels. The treatments had no significant effect on the relative weights of the heart, liver, and residual yolk in the intestine at one day of life. Overall, it can be concluded that injecting local chicken blood plasma did not affect hatchability. This was accompanied by an improvement in the immune status of the hatched chicks, as evidenced by a decline in the white blood cell count and a rise in globulins. [ABSTRACT FROM AUTHOR]

This study is focused on investigating parental involvement in students' mathematical activities. It presents a comprehensive bibliometric analysis that examines new areas of research to discover current trends and future research opportunities related to parental involvement in their children's mathematics activities. This study intends to provide a meaningful contribution toward enhancing educational interventions in the future. The metadata of the publications included in this analysis was extracted from the Scopus and ERIC databases using the search criteria "(parent OR parent) AND (involvement OR support) AND (math or math) AND student." After the screening step, a comprehensive analysis was conducted on a total of 944 articles using the tools Harzing's Publish or Perish 8, Biblioshiny, and VOSviewer 1.6.20. The findings indicated that studies on this topic covered 42 years and accumulated a total of 17,392 citations. The most prolific year in terms of publications was 2023, with a peak of 80 studies published. The leading contributors to this body of research were Jianzhong Xu and James Reed Campbell, each authoring six papers. The keyword mapping results revealed several interesting research avenues for future investigation, such as the incorporation of psychological interventions, longitudinal studies, multidisciplinary approaches, and the utilization of technology. [ABSTRACT FROM AUTHOR]

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Detoxification is one of the most important liver functions. Therefore, liver is the front line of defense when the biosystem faces drug overdose, toxins, and anything that may cause harm. Some famous antibiotics are known for their side effects on liver; one of them is amoxicillin, AM. This work has investigated the toxic effect of amoxicillin on rat's liver with overdose (90 mg/kg) and has studied the ameliorative role of protective and therapeutic Ashwagandha seeds extract (ASE) at doses (100, 200, and 300 mg/kg) against this toxicity. To achieve this work, the authors used two modalities; the first is liver histopathology to figure out the amoxicillin and ASE effects and to detect the sensitivity of another modality; the electric modulus, and its related thermodynamic parameters of liver tissue. Histopathological examination showed that the role of therapeutic ASE in reducing amoxicillin (AM) toxicity was more effective than the protective one. Also, most dielectric and thermodynamic results achieved the same result. Histopathology confirmed the liver injury by amoxicillin and the partial repair by the biosystem using ASE. Moreover, electric modulus, related dielectric parameters, and their thermodynamic state functions showed different changes in their values under the effect of amoxicillin. Using ASE helped the biosystem to restore these changes near their control values. [ABSTRACT FROM AUTHOR]