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Proton Exchange Membrane Fuel Cells (PEMFCs) offer a clean and sustainable alternative to traditional engines. PEMFCs play a vital role in progressing hydrogen-based energy solutions. Accurate modeling of PEMFC performance is essential for enhancing their efficiency. This paper introduces a novel reinforcement learning (RL) approach for estimating PEMFC parameters, addressing the challenges of the complex and nonlinear dynamics of the PEMFCs. The proposed RL method minimizes the sum of squared errors between measured and simulated voltages and provides an adaptive and self-improving RL-based Estimation that learns continuously from system feedback. The RL-based approach demonstrates superior accuracy and performance compared with traditional metaheuristic techniques. It has been validated through theoretical and experimental comparisons and tested on commercial PEMFCs, including the Temasek 1 kW, the 6 kW Nedstack PS6, and the Horizon H-12 12 W. The dataset used in this study comes from experimental data. This research contributes to the precise modeling of PEMFCs, improving their efficiency, and developing wider adoption of PEMFCs in sustainable energy solutions. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) contain a diverse array of microbes, underscoring the need for regular monitoring to ensure treatment efficacy and protect health. However, detailed studies on waste stabilization ponds (WSPs) are scarce. This study evaluates a full-scale WSP, located in Giza Governorate, Egypt, including anaerobic, facultative, and maturation ponds, examining an array of parameters such as enteric viruses, microeukaryotes (protozoa and algae), bacterial indicators, bacterial pathogens, and physicochemical characteristics. Utilizing multivariate statistical models, we identified significant distinctions in physicochemical parameters and microbial communities, primarily driven by treatment stages rather than temporal variations. In addition, seven viruses (human rotavirus, adenovirus, norovirus, astrovirus, hepatitis A virus, polyomavirus, and papillomavirus) were detected during the different stages (inlet, anaerobic, facultative, and outlet) of the WSP, except norovirus and papillomavirus were absent in the outlet stage. The viral log means reductions ranged from 1.24 to 5.94, depending on the stage and virus type. The removal efficiency of bacterial pathogens was more than 99%. High throughput 18S rRNA gene amplicon sequencing indicated the dominance of animal parasitic Apicomplexa species and Vermamoeba spp. in the WSP. Network analysis indicated significant roles for Ciliophora in virus reduction. Notably, the maturation pond's outlet was dominated by Spirulina maxima, whose mat-forming tendencies may inhibit pathogen removal by providing protective shelters. Although the WSP effectively reduced pathogen levels, the high initial loads resulted in considerable concentrations in the final effluent, posing ongoing public health concerns. This study highlights the imperative of including pathogen standards in national regulations for wastewater reuse. [ABSTRACT FROM AUTHOR]

Background: The normal course of the body's disintegration after death, starting at the cellular level, is known as postmortem changes. The changes that start right after death last for a long time to different organs at varying speeds. Many internal and external factors influence the start and severity of these changes. The rates are imprecise, vary across different geographic regions, and fluctuate seasonally within a single geographic location. One of the main goals of the forensic autopsy is to estimate the postmortem interval (PMI), or time since death, and understanding postmortem changes is crucial for this purpose. Aim: The current review provides a view of understanding postmortem changes, their classifications, their time of onset, their rate, and the factors influencing them. Conclusions: In summary, researchers have classified postmortem changes according to their order of appearance and they emphasize the value of understanding postmortem changes in the forensic field. [ABSTRACT FROM AUTHOR]

Offshore wind farms (OWFs) play a crucial role in producing renewable energy in modern electrical power systems. However, to ensure that these facilities operate smoothly, they require robust control systems. As a result, this paper employed the newly developed Walrus Optimization algorithm (WaOA) to optimize the design parameters of fractional-order proportional-integral-derivative (FOPID) controllers in the power electronic interface circuits of the studied wind energy conversion system (WECS). In contrast to conventional optimization techniques like GA and PSO, the suggested approach proves more effective. The paper validates the WaOA application in optimizing FOPID controllers within a WECS comprising two, onshore and offshore, VSC stations at the two ends of an HVDC transmission system connecting OWFs to the mainland. The study shows that the WaOA outperforms GA and PSO, improving system stability and enabling quick recovery after disturbances. The study carried out using MATLAB/Simulink highlights the significance of newly recently introduced optimization techniques to ensure efficient and reliable operation of offshore wind energy systems, thereby expediting the transition to sustainable energy sources. [ABSTRACT FROM AUTHOR]

Background: Neonatal hyperbilirubinemia (NH) affects over 80% of premature babies & 60% of fullterm babies in the first week of life. There are two forms of neonatal hyperbilirubinemia: conjugated & unconjugated. Unconjugated forms can cause bilirubin encephalopathy & kernicterus in extreme cases, while conjugated forms are thought to be a result of a systemic sickness. Babies born prematurely are at a higher risk of hyperbilirubinemia due to bilirubin-induced brain damage compared to their term counterparts. Aim and objectives: The study aims to assess the effect of phototherapy on liver enzymes, renal functions, in NH patients before and after phototherapy. Subjects and methods: This was an observational cross-sectional study that was performed at neonatal intensive care unit (NICU) Al-Hussein university hospital. It included 100 term infants of both sex that received phototherapy for management of neonatal indirect hyperbilirubinemia. When indicated according to Bhutani Nomogram curve. Result: There is no statistically significant difference was found between group I that treated by conventional phototherapy only and group II that treated by intensive then conventional phototherapy regarding maternal age, ABO blood groups and Rh status maternal comorbidities like gestational HTN or diabetes, gestational age, onset of jaundice. Also Both therapy groups reduced total and direct bilirubin significantly (Paired sample t test, P = 0.000). Group II had a greater total bilirubin reduction than group I (Independent sample t test, P = 0.001). Both therapy groups had significant ALT, AST, ALP, urea and creatinine reductions (Paired sample t test, P = 0.000). Conclusion: As regard the effect of Phototherapy on liver enzymes and kidney functions, our results showed a statistically significant reduction in ALT, AST, ALP, urea and creatinine in both treated groups. [ABSTRACT FROM AUTHOR]

Reactive power compensation (RPC) is a big problem during power system operation. Parenthetically, capacitor allocation and sizing may be the only convenient solution for RPC of power systems. The loss sensitivity factor (LSF) is applied here for finding the optimum capacitor position. This paper presents quasi-oppositional fast convergence evolutionary programming (QOFCEP), fast convergence evolutionary programming (FCEP), and evolutionary programming (EP) for the optimum location and sizing of shunt capacitors in the isolated microgrid (MG) for minimizing total real power loss throughout the day with and without the demand response program (DRP). The 33-node, 69-node, and 118- node isolated MGs have been studied to authenticate the efficacy of the suggested approach. Each MG includes small hydro power plants (SHPPs), solar PV plants (SPVPs), wind turbine generators (WTGs), diesel generators (DGs), and plug-in electric vehicles (PEVs). [ABSTRACT FROM AUTHOR]

For the first time in this study, silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) were green synthesized by the cost-effective and eco-friendly procedure using Cotton seed meal and Fodder yeast extracts. The biosynthesized NPs were characterized by UV–Vis spectroscopy, dynamic light scattering analysis (DLS), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and fourier-transform infrared (FTIR) spectroscopy. Furthermore, the biosynthesized NPs were tested in vitro against biofilm formation by some pathogenic negative bacteria (Escherichia coli, Proteus mirabilis, Klebsiella sp., Salmonella sp., and Pseudomonas aeruginosa) and negative bacteria (staphylococcus aureus) as well as against human denovirus serotype 5 (HAdV-5) and anticancer activity using HepG2 hepatocarcinoma cells. UV–Vis absorption spectra of reaction mixture of AgNPs and AuNPs exhibited maximum absorbance at 440 nm and 540 nm, respectively. This finding was confirmed by DLS measurements that the highest intensity of the AgNPs and AuNPs were 84 nm and 73.9 nm, respectively. FTIR measurements identified some functional groups detected in Cotton seed meal and Fodder yeast extracts that could be responsible for reduction of silver and gold ions to metallic silver and gold. The morphologies and particle size of AgNPs and AuNPs were confirmed by the TEM and SAED pattern analysis. Biosynthesized AgNPs and AuNPs showed good inhibitory effects against biofilms produced by Escherichia coli, Proteus mirabilis, Klebsiella sp., Salmonella sp., Pseudomonas aeruginosa, and Staphylococcus aureus. In addition, they showed anticancer activities against hepatocellular carcinoma (HepG-2) and antiviral activity against human adenovirus serotype 5 infection in vitro. Finally, the results of this study is expected to be extremely helpful to nano-biotechnology, pharmaceutical, and food packing applications through developing antimicrobial and/or an anticancer drugs from ecofriendly and inexpensive nanoparticles with multi-potentiality. [ABSTRACT FROM AUTHOR]

Bostonite rocks are widely spread in the Central Eastern Desert (CED) of Egypt, they are found in the form of sills or dykes injected in the Precambrian rocks. Postgeosynclinal (Hammamat) sediments were intruded by Postorogenic bostonites. The study of this area, using ground geophysical methods, aimed at tracking the radioactive mineralization under the surface, based on the possible association of this radioactive mineralization with some other mineralizations such as sulphides. The application of the self-potential survey shows that the highest negative anomalies are associated with the South El-Atshan bostonite sill and its contact zones. The depths to the centres of some selected anomalies range from 5.7 m to 24 m, half-widths oscillate from 6 to 32 m, with shallow dips towards the west and east directions. The horizontal-loop electromagnetic (HLEM) survey, which was conducted using four frequencies, revealed the presence of two conductive bodies. These conductive bodies possess narrow widths and depths, ranging from 25 m to 27 m, dipping towards the west direction with shallow angles of 25◦ and 40◦, respectively. In addition, the induced polarization (IP) profile shows high chargeability values reaching more than 7.9 mV/V at depths starting from about 10 m to about 35 m. This zone corresponds to a high-resistance zone that may reflect a subsurface disseminated mineralization. The integration of the results obtained using the three techniques makes it possible to determine the most appropriate zones for the development of exploration in the area of investigation. [ABSTRACT FROM AUTHOR]

Health care workers (HCWs) may be at a variable risk of SARS-CoV2 infection. Regardless of their involvement in providing direct clinical treatment, most of the prior research had included all HCWs. Understanding infection rates, risk factors and outcomes among different subgroups of HCWs is crucial. From February 28, 2020 to January 1, 2022, we conducted a retrospective analysis encompassing all full-time non-clinical staff (NCS) subcontracted with Hamad Medical Corporation (HMC) facilities. To determine current or previous SARS-CoV2 infection, all personnel underwent RT-PCR and/or serology testing. To identify the demographic factors linked to the risk of infection, we utilized Cox-Hazard regression analysis. Herein 3158/6231 (50.7%) subcontracted NCS tested positive for SARS-CoV-2 by RT-PCR or serology during the research period. The median age was 30 years (IQR 25,35), 69.8% of the population were males, 82.4% were from South Asia, 86.6% did not have any concomitant conditions. 6032 (96.8%) of the population lived in shared housing, while 4749 (76.2%) had low to median levels of education. While infection (PCR positive with or without seropositive results) was independently predicted by male gender, working in the catering, laundry, and security sectors and being intermediate (7-12 years of education), lower (0-6 years of education), higher (exposure to confirmed case), and having symptoms. Male gender, working in the security sectors and being intermediate (7-12 years of education) were independently associated with accidently detected cases (PCR negative and seropositive). 299 (4.8%) required hospitalization, of them 3 cases were severe pneumonia and one required ICU admission without mechanical ventilation, with no deaths reported. In conclusion Infection rates among NCS are high. The majority are asymptomatic and may contribute to ongoing illness spread in the public or in healthcare facilities. During a pandemic, routine screening of this population is crucial and may aid in containing the spread of infection., 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 Published by Elsevier Inc.)