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A new technique for fault diagnosis in transformer insulating oil based on infrared spectroscopy measurements

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high Voltage 2024年第2期9卷 319-335页

作者： Mohamed M.f.Darwish Mohamed h.A.hassan Nagat M.K.Abdel-Gawad Matti Lehtonen Diaa-Eldin A.Mansour Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland Department of Electrical Power Engineering Egypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityEgypt Department of Electrical Power and Machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical *** gas analysis(DGA)is frequently used for this ***,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of ***,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault ***,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to ***,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGA method for fault diagnosis in insulating *** inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°Chat,two test cells were crafted especially for serving the simulation processes inside the laboratory for both types of inception ***,six samples of pure paraffinic mineral oil were taken to be degraded in the *** that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by fourier transform infrared(fTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault *** that,the fTIR analysis was initially verified utilising the DGA ***,for further affirmation,the dielectric dissipation factor(DDf)for all samples was *** the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.

关键词： fault diagnosis spectroscopy

MgO-attached graphene nanosheet(MgO@GNS)reinforced magnesium matrix nanocomposite with superior mechanical,corrosion and biological performance

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2062-2076页

作者： S.Abazari A.Shamsipur h.R.Bakhsheshi-Rad M.S.Soheilirad f.Khorashadizade S.S.Mirhosseini Department of Materials and Metallurgical Engineering Amirkabir University of TechnologyTehran ***Iran Iranian National Standards Organization of hormozgan HormozganIran Advanced Materials Research Center Department of Materials EngineeringNajafabad BranchIslamic Azad UniversityNajafabadIran Department of Materials and Metallurgical Engineering Iran University of Science and TechnologyTehranIran

Magnesium(Mg)alloys are gaining great consideration as body implant materials due to their high biodegradability and ***,they suffer from low corrosion resistance and antibacterial *** this research,semi-powder metallurgy followed by hot extrusion was utilized to produce the magnesium oxide@graphene nanosheets/magnesium(MgO@GNS/Mg)composite to improve mechanical,corrosion and cytocompatibility *** have revealed that the incorporation of MgO@GNS nanohybrids into Mg-based composite enhanced microhardness and compressive *** vitro,osteoblast cell culture tests show that using MgO@GNS nanohybrid fillers enhances osteoblast adhesion and apatite *** presence of MgO@GNS nanoparticles in the composites decreased the opening defects,micro-cracks and micro-pores of the composites thus preventing the penetration of the corrosive solution into the *** demonstrated that the MgO@GNS/Mg composite possesses excellent antibacterial properties because of the combination of the release of MgO and physical damage to bacterium membranes caused by the sharp edges of graphene nanosheets that can effectively damage the cell wall thereby facilitating penetration into the bacterial lipid ***,the MgO@GNS/Mg composite with high mechanical strength,antibacterial activity and corrosion resistance is considered to be a promising material for load-bearing implant applications.

关键词： metal matrix composites MgO@GNS nanohybrid strengthening mechanisms antibacterial activity biocompatibility

SARS-CoV-2 variants are associated with different clinical courses in children with MIS-C

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World Journal of Pediatrics 2024年第2期20卷 143-152页

作者： Andres f.Moreno Rojas Emelia Bainto helen harvey Adriana h.Tremoulet Jane C.Burns Kirsten B.Dummer Department of Pediatrics Division of Pediatric CardiologyUniversity of California San Diegoand Rady Children’s Hospital3020 Children’s Way MC 5004San DiegoCA 92123USA Kawasaki Disease Research Center La JollaCAUSA Department of Pediatrics Division of Pediatric Critical CareUniversity of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA Department of Pediatrics University of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA

Background Recent infection with SARS‑CoV-2 in children has been associated with multisystem inflammatory syndrome in children(MIS-C).SARS‑CoV-2 has undergone different *** publications exist about specific variants and their correlation with the severity of *** This was a single-center,retrospective study including all patients admitted with MIS-C at Rady Children’s hospital-San Diego between May 2020 and March *** epidemiologic data,including viral genomic information,were obtained from public ***,clinical presentation,laboratory values,and outcomes were obtained from electronic medical *** The analysis included 104 pediatric *** MIS-C waves were *** variants in San Diego during the first wave included clades 20A to *** the second wave,there were variants from clades 20A to C,20G,21C(Epsilon),20I(Alpha),and 20J(Gamma).The third wave had Delta strains(clades 21A,21I,and 21J),and the fourth had Omicron variants(clades 21K,21L,and 22C).MIS-C presented with similar symptoms and laboratory findings across all *** patients were admitted to the pediatric intensive care unit(PICU)(74%)and required inotropic support(63%)during the second *** of the patients required mechanical circulatory support,and only two required invasive ventilatory *** was no *** The various strains of SARS-CoV-2 triggered MIS-C with differing severities,with the second wave having a more severe clinical *** the differences in disease severity across variants were due to changes in the virus or other factors remains unknown.

关键词： Complications COVID-19 MIS-C SARS-CoV-2 variants

Novel Sustainable Cellulose Acetate Based Biosensor for Glucose Detection

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Journal of Renewable Materials 2024年第2期12卷 369-380页

作者： M.f.Elkady E.M.El-Sayed Mahmoud Samy Omneya A.Koriem h.Shokry hassan Chemical and Petrochemical Engineering Department Egypt-Japan University of Science and TechnologyNew Borg El-ArabAlexandriaEgypt fabrication Technology Research Department Advanced Technology and New Materials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-ArabAlexandria21934Egypt Department of Public Works Engineering Faculty of EngineeringMansoura UniversityMansoura35516Egypt Environmental Engineering Department Egypt-Japan University of Science and TechnologyNew Borg El-ArabAlexandriaEgypt Electronic Materials Research Department Advanced Technology and NewMaterials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-ArabAlexandria21934Egypt

In this study,green zinc oxide(ZnO)/polypyrrole(Ppy)/cellulose acetate(CA)film has been synthesized via solvent *** film was used as supporting material for glucose oxidase(GOx)to sensitize a glucose *** nanoparticles have been prepared via the green route using olive leaves extract as a ***/Ppy nanocomposite has been synthesized by a simple in-situ chemical oxidative polymerization of pyrrole(Py)monomer using ferric chloride(feCl3)as an oxidizing *** produced materials and the composite films were characterized using X-ray diffraction analysis(XRD),scanning electron microscope(SEM),fourier transform infrared(fTIR)and thermogravimetric analysis(TGA).Glucose oxidase was successfully immobilized on the surface of the prepared film and then ZnO/Ppy/CA/GOx composite was sputtered with platinum electrode for the current determination at different initial concentrations of *** measurements proved the suitability and the high sensitivity of the constructed biosensor for the detection of glucose levels in different *** performance of the prepared biosensor has been assessed by measuring and comparing glucose concentrations up to 800 *** results affirmed the reliability of the developed biosensor towards real samples which suggests the wide-scale application of the proposed biosensor.

关键词： Biosensors composite films glucose polypyrrole green ZnO cellulose acetate

Monogenic features of urolithiasis: A comprehensive review

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Asian Journal of Urology 2024年第2期11卷 169-179页

作者： Kyo Chul Koo Abdulghafour halawani Victor K.f.Wong Dirk Lange Ben h.Chew Department of Urology Yonsei University College of MedicineSeoulRepublic of Korea Department of Urology King Abdulaziz UniversityJeddahSaudi Arabia Department of Urological Sciences University of British ColumbiaStone Centre at Vancouver General HospitalVancouverBritish ColumbiaCanada

Objective: Urolithiasis formation has been attributed to environmental and dietary factors. however, evidence is accumulating that genetic background can contribute to urolithiasis formation. Advancements in the identification of monogenic causes using high-throughput sequencing technologies have shown that urolithiasis has a strong heritable ***: This review describes monogenic factors implicated in a genetic predisposition to urolithiasis. Peer-reviewed journals were evaluated by a PubMed search until July 2023 to summarize disorders associated with monogenic traits, and discuss clinical implications of identification of patients genetically susceptible to urolithiasis ***: Given that more than 80% of urolithiases cases are associated with calcium accumulation, studies have focused mainly on monogenetic contributors to hypercalciuric urolithiases, leading to the identification of receptors, channels, and transporters involved in the regulation of calcium renal tubular reabsorption. Nevertheless, available candidate genes and linkage methods have a low resolution for evaluation of the effects of genetic components versus those of environmental, dietary, and hormonal factors, and genotypes remain undetermined in the majority of urolithiasis ***: The pathophysiology underlying urolithiasis formation is complex and multifactorial, but evidence strongly suggests the existence of numerous monogenic causes of urolithiasis in humans.

关键词： Gene Genetic expression Inheritance pattern Urolithiasis

Modelling dynamic pantograph loads with combined numerical analysis

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Railway Engineering Science 2024年第1期32卷 81-94页

作者： f.f.Jackson R.Mishra J.M.Rebelo J.Santos P.Antunes J.Pombo h.Magalhaes L.Wills M.Askill School of Computing and Engineering University of HuddersfieldHuddersfieldUK School of Computing and Engineering Institute of Railway ResearchUniversity of HuddersfieldHuddersfieldUK IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal ISEL Instituto Politecnico de LisboaLisbonPortugal hitachi Rail Newton AycliffeUK Wabtec/Brecknell Willis ChardUK

Appropriate interaction between pantograph and catenary is imperative for smooth operation of electric *** heights of overhead lines to accommodate level crossings,overbridges,and tunnels pose significant challenges in maintaining consistent current collection performance as the pantograph aerodynamic profile,and thus aerodynamic load changes significantly with operational *** research aims to analyse the global flow characteristics and aerodynamic forces acting on individual components of an hSX pantograph operating in different configurations and orientations,such that the results can be combined with multibody simulations to obtain accurate dynamic insight into contact ***,computational fluid dynamics simulations are used to investigate the pantograph component loads in a representative setting,such as that of the recessed cavity on a Class 800 *** an aerodynamic perspective,this study indicates that the total drag force acting on non-fixed components of the pantograph is larger for the knuckle-leading orientation rather than the knuckle-trailing,although the difference between the two is found to reduce with increasing pantograph *** the aerodynamic loads acting on individual components with multibody tools allows for realistic dynamic insight into the pantograph *** results obtained show how considering aerodynamic forces enhance the realism of the models,leading to behaviour of the pantograph-catenary contact forces closely matching that seen in experimental tests.

关键词： Pantograph-catenary interaction Pantograph aerodynamics Computational fluid dynamics Pantograph loads Current collection performance

Oxide-supported metal catalysts for anaerobic NAD+regeneration with concurrent hydrogen production

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Chinese Chemical Letters 2024年第2期35卷 263-267页

作者： Jianwei Li Joseph W.h.Burnett Claudia Martinez Macias Russell f.howe Xiaodong Wang Chemical Engineering School of EngineeringLancaster UniversityLancaster LA1 4YWUnited Kingdom Chemistry Department University of AberdeenAberdeen AB24 3UEUnited Kingdom

We report SiO_(2)-supported monometallic Pt,Pd,Au,Ni,Cu and Co catalysts for proton-driven NAD+regeneration,co-producing h_(2).All metals are fully selective to NAD+where the order of turnover frequencies(Pt>Pd>Cu>Au,Ni and Co)coincides with those otherwise observed in electrochemical hydrogen evolution *** has revealed that NADh is capable of converting the metal sites into a“cathode”without an external potential and the NADh to NAD+reaction involves transferring electron and hydrogen atom ***-deficient Ptδ+(on CeO_(2))enhances TOf and the heterogeneous Pt/CeO_(2) catalyst is recyclable without losing any activity/selectivity.

关键词： NAD+regeneration heterogeneous catalyst hydrogenase mimic hydrogen binding energy hydrogen production

Effect of nutrition-related infodemics and social media on maternal experience: A nationwide survey in a low/middle income country

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World Journal of Clinical Pediatrics 2024年第1期13卷 93-106页

作者： Marwa M Zein Noha Arafa Mortada h f El-Shabrawi Nehal Mohammed El-Koofy Department of Public health and Community Medicine Cairo UniversityCairo 515211Egypt Department of Pediatric Endocrinology and Diabetes Children's HospitalKasralainy Medical SchoolCairo UniversityCairo 515211Egypt Department of Pediatrics Cairo UniversityCairo 12411Egypt Department of Pediatrics The Children's HospitalCairo UniversityCairo 12411Egypt

BACKGROUND Undernutrition is a crucial cause of morbidity and mortality among children in low-or middle-income countries(LMICs).A better understanding of maternal general healthy nutrition knowledge,as well as misbeliefs,is highly essential,especially in such *** the current era of infodemics,it is very strenuous for mothers to select not only the right source for maternal nutrition information but the correct information as *** To assess maternal healthy nutritional knowledge and nutrition-related misbeliefs and misinformation in an LMIC,and to determine the sources of such information and their assessment *** This cross-sectional analytical observational study enrolled 5148 randomly selected Egyptian mothers who had one or more children less than 15 years *** data were collected through online questionnaire forms:One was for the general nutrition knowledge assessment,and the other was for the nutritional myth *** of information and ways of evaluating internet sources using the Currency,Relevance,Authority,Accuracy,and Purpose test were additionally *** The mean general nutrition knowledge score was 29±9,with a percent score of 70.8%±12.1%(total score:41).The median myth score was 9(interquartile range:6,12;total score:18).The primary sources of nutrition knowledge for the enrolled mothers were social media platforms(55%).half of the mothers managed information for currency and authority,except for considering the author's contact *** than 60%regularly checked information for accuracy and *** mothers with significant nutrition knowledge checked periodically for the author's contact information(P=0.012).The nutrition myth score was significantly lower among mothers who periodically checked the evidence of the information(P=0.016).Mothers dependent on their healthcare providers as the primary source of their general nutritional knowledge were less likely to hold myths by 13%(P=0.044).however,usi

关键词： Nutrition Infodemics Maternal knowledge Myth Low/middle income country

Dysprosium oxide,alumina,and graphene oxide reinforced polycaprolactone thin films:Thermal stability,morphology,and cell viability

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Journal of Rare Earths 2024年第7期42卷 1337-1343,I0005页

作者： Mohamed Tharwat Elabbasy Mohamed R.Atteya Mai A.Samak Mousa Abdelrahman Tahani AlMahmoud M.A.El-Morsy A.A.Menazea M.f.h.Abd El-Kader Department of Public health College of Public Health and Health InformaticsUniversity of Ha'ilHa'il2440Saudi Arabia food Control Department Faculty of Veterinary MedicineZagazig UniversityZagazig44519Egypt Department of Physical Therapy College of Applied Medical SciencesUniversity of Ha'ilHa'ilSaudi Arabia Department of histology and Cell Biology Faculty of MedicineZagazig UniversityZagazig44519Egypt College of Nursing University of Ha'ilHa'ilSaudi Arabia College of Science and humanities in Al-Kharj Physics DepartmentPlasma Technology and Material Science UnitPrince Sattam Bin Abdulaziz UniversityAl-kharj11942Saudi Arabia Physics Department Faculty of ScienceUniversity of DamiettaNew Damietta34517Egypt Spectroscopy Department Physics Research InstituteNational Research CentreDokki12622GizaEgypt Biophysics Department Faculty of ScienceCairo UniversityGizaEgypt

Developing a biomaterial for wound healing applications is still a ***,dysprosium oxide(Dy_(2)O_(3)),aluminum oxide(Al_(2)O_(3)),and graphene oxide(GO)were embedded in cast films based on polycaprolactone(PCL)to be examined for wound dressing *** techniques were used to characterize the fabricated films including X-ray diffraction(XRD),fourier transform infrared spectroscopy(fTIR),Raman,and scanning electron microscopy(SEM),besides their biological *** thermogravimetric analysis(TGA)exhibits high thermal stability as the scaffold weight decreases slightly to 98.6%after raising the temperature from room temperature to 280℃.The cell viability was investigated and it is shown that the viable cells grow up to approximately 93%at 75μg/***,the cell attachment shows excellent behavior as the cells attach on most of the surface of the modified PCL which shows high biocompatibility.

关键词： Wound healing Polycaprolactone Dy_(2)O_(3) Al_(2)O_(3) Biocompatible Rare earths