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Converting TREx-RGB green-channel data to 557.7 nm auroral intensity:methodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.m.Gillies E.Spanswick E.f.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and airglow.Because the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TREx-RGB camera is usually dominated by the 557.7 nm emission.Under this rationale,the TREx mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm aurora.In this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB data.We illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TREx spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-Earth-orbit satellites,with the aid of an auroral transport model.We demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake stations.The RGB response is found to be nonlinear.Empirical conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TREx-RGB data users.The methodology established in this study will also be applicable to the upcoming SmILE ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TREx RGB green-line aurora auroral transport model

Sex differences in the risk of retinopathy of prematurity:a systematic review,frequentist and Bayesian meta‑analysis,and meta‑regression

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World Journal of Pediatrics 2024年第4期20卷 340-352页

作者： Tamara m.Hundscheid Silvia Gulden mohamad f.Almutairi františek Bartoš Giacomo Cavallaro Eduardo Villamor Division of Neonatology Department of PediatricsMosaKids Children’s HospitalMaastricht University Medical Center(MUMC+)School for Oncology and Reproduction(GROW)Maastricht UniversityP.Debyelaan 25.P.O.Box 58006202 AZ MaastrichtThe Netherlands Neonatal Intensive Care Unit Sant’Anna HospitalComoItaly Department of Psychology University of Amsterdam1001 NK AmsterdamThe Netherlands Neonatal Intensive Care Unit Fondazione IRCCS Ca’Granda Ospedale Maggiore PoliclinicoMilanItaly

Background Retinopathy of prematurity(ROP)is generally considered to be more frequent in males than in females.However,it is not known whether sex differences in ROP affect all degrees of the condition,are global and have changed as neonatology has developed.We aimed to conduct a systematic review and meta-analysis of studies addressing sex differences in the risk of developing ROP.methods Pubmed/mEDLINE and Embase databases were searched.The frequentist,random-effects risk ratio(RR)and 95%confidence interval(CI)were calculated.Bayesian model averaged(BmA)meta-analysis was used to calculate the Bayes factors(Bfs).The Bf10 is the ratio of the probability of the data under the alternative hypothesis(H1)over the probability of the data under the null hypothesis(H0).Results We included 205 studies(867,252 infants).frequentist meta-analysis showed a positive association between male sex and severe ROP(113 studies,RR=1.14,95%CI=1.07–1.22)but no association with any ROP(144 studies,RR=1.00,95%CI=0.96–1.03).BmA showed extreme evidence in favor of H1 for severe ROP(Bf10=71,174)and strong evidence in favor of H0 for any ROP(Bf10=0.05).The association between male sex and severe ROP remained stable over time and was present only in cohorts from countries with a high or high-middle sociodemographic index.Conclusions Our study confirms the presence of a male disadvantage in severe ROP but not in less severe forms of the disease.There are variations in the sex differences in ROP,depending on geographical location and sociodemographic level of the countries.

关键词： Oxidative stress Retinopathy of prematurity Sex characteristics

Carbon monoxide as C1 Building Block in fine Chemical Synthesis

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Chinese Journal of Chemistry 2024年第2期42卷 199-221页

作者： Rui m.B.Carrilho mario J.f.Calvete Gabor mikle Laszlo Kollar mariette m.Pereira University of Coimbra Coimbra Chemistry CentreDepartment of ChemistryRua Larga3004-535 CoimbraPortugal Department of General and Inorganic Chemistry and ELKH-PTE Research Groupfor Selective Chemical Syntheses University of PecsIfjusag utja 6H-7624 PecsHungary

Carbon monoxide(CO)has become one of the most relevant and versatile renewable C1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its activation.In this review,we present a comprehensive critical analysis of the last 10 years literature on the use of CO as a renewable feedstock for fine chemicals production.The review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and C-H carbonylation.Notable examples of the synthesis of relevant building blocks and/or known pharmaceuticals are highlighted.Emphasis is placed on examples of utilizing CO as the C1 building block in one or more catalytic steps.The catalyst used and the reaction conditions are consistently presented throughout all of the examples.

关键词： Carbon monoxide fine chemicals Carbonylation Hydroformylation C-H functionalization

Threshold-Based Software-Defined Networking(SDN)Solution for Healthcare Systems against Intrusion Attacks

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Computer modeling in Engineering & Sciences 2024年第2期138卷 1469-1483页

作者： Laila m.Halman mohammed J.f.Alenazi Department of Computer Engineering College of Computer ScienceKing Saud UniversityRiyadh11451Saudi Arabia

The healthcare sector holds valuable and sensitive data.The amount of this data and the need to handle,exchange,and protect it,has been increasing at a fast pace.Due to their nature,software-defined networks(SDNs)are widely used in healthcare systems,as they ensure effective resource utilization,safety,great network management,and monitoring.In this sector,due to the value of thedata,SDNs faceamajor challengeposed byawide range of attacks,such as distributed denial of service(DDoS)and probe attacks.These attacks reduce network performance,causing the degradation of different key performance indicators(KPIs)or,in the worst cases,a network failure which can threaten human lives.This can be significant,especially with the current expansion of portable healthcare that supports mobile and wireless devices for what is called mobile health,or m-health.In this study,we examine the effectiveness of using SDNs for defense against DDoS,as well as their effects on different network KPIs under various scenarios.We propose a threshold-based DDoS classifier(TBDC)technique to classify DDoS attacks in healthcare SDNs,aiming to block traffic considered a hazard in the form of a DDoS attack.We then evaluate the accuracy and performance of the proposed TBDC approach.Our technique shows outstanding performance,increasing the mean throughput by 190.3%,reducing the mean delay by 95%,and reducing packet loss by 99.7%relative to normal,with DDoS attack traffic.

关键词： Network resilience network management attack prediction software defined networking(SDN) distributed denial of service(DDoS) healthcare

Classical taxonomy,molecular phylogeny and genetic analysis of the genus Exitianus Ball,1929(Hemiptera:Cicadellidae:Deltocephalinae)from Egypt

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Zoological Systematics 2024年第2期49卷 143-157页

作者： Rabab m.El-Hady Ahmed f.El-Sayed Survey&Taxonomy Department Plant Protection Research InstituteAgriculture Research CentreGizaEgypt microbial Genetics Department Biotechnology Research InstituteNational Research CentreGizaEgypt Egypt Center for Research and Regenerative medicine(ECRRm) CairoEgypt

Egyptian species of the leafhopper genus Exitianus Ball,1929,E.capicola(St?l,1855),E.nanus(Distant,1908),and E.pondus Ross,1968 are reviewed.Illustrations,morphological descriptions,and a key for their identification are provided.In this study,we used molecular techniques to confirm morphological identification and detect phylogeny among the three Exitianus species.The partial nucleotide sequences of the amplified products obtained were determined by macrogen Korea.The nucleotide sequences of 28S rDNA and COX genes of the EGY-ARC-9,EGY-ARC-4,and EGY-ARC-5 were determined by macrogen Korea,blasted into BLAST at the National Center for Biotechnology Information website(NCBI)and compared with those deposited in the GenBank DNA database.The results represented the homology percentage between the partial sequences of the 28S rRNA and COX genes from each species and related species obtained from GenBank DNA database.The morphological identifications of the three Exitianus species were confirmed by molecular characterization and sequencing of 28S rDNA and COX genes and identified as E.capicola,E.nanus,and E.pondus.Also,their sequences of 28srDNA and COX genes were deposited in GenBank with an accession number(LC670610,LC670607,and OQ196105)for 28srDNA gene and(LC775357,LC775358,and LC775359)for the COX gene.

关键词： Auchenorrhyncha Chaismini taxonomic 28S rDNA phylogenetic

Effect of solidification cooling rate on microstructure and tribology characteristics of Zn-4Si alloy

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International Journal of minerals,metallurgy and materials 2024年第2期31卷 362-373页

作者： f.Akbari m.Golkaram S.Beyrami G.Shirazi K.mantashloo R.Taghiabadi m.Saghafi Yazdi I.Ansarian Department of metallurgy and material Science Imam Khomeini International University(IKIU)Qazvin ***Iran

The main objective of this work was to modify the microstructure and enhance the tribological properties of a new Zn-4Si al-loy through a high solidification cooling rate(SCR).According to the results,by increasing the SCR from 2.0 to 59.5℃/s the average size of primary Si particles and that of the grains reduced from 76.1 and 3780μm to less than about 14.6 and 460μm,respectively.Augment-ing the SCR also enhanced the microstructural homogeneity,decreased the porosity content(by 50%),and increased the matrix hardness(by 36%).These microstructural changes enhanced the tribological behavior.for instance,under the applied pressure of 0.5 mPa,an in-crease in the SCR from 2.0 to 59.5℃/s decreased the wear rate and the average friction coefficient of the alloy by 57%and 23%,respect-ively.The wear mechanism was also changed from the severe delamination,adhesion,and abrasion in the slowly-cooled alloy to the mild tribolayer delamination/abrasion in the high-cooling-rate-solidified sample.

关键词： zinc-silicon alloy primary silicon solidification cooling rate tribology sliding wear

An unexpected cellular fountain of youth:platelets provide factors rejuvenating brain functions

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Signal Transduction and Targeted Therapy 2024年第1期9卷 16-18页

作者： Harald f.Langer Department of Cardiology AngiologyHaemostaseology and Medical Intensive CareUniversity Medical Centre MannheimMedical Faculty MannheimHeidelberg UniversityMannheimGermany German Centre for Cardiovascular Research(DZHK) Partner Site Heidelberg/MannheimMannheimGermany European Center for Angioscience Medical Faculty MannheimHeidelberg UniversityMannheimGermany Cardiovascular systems biology Medical Clinic IUniversity Heart Center LübeckLübeckGermany

In a recent manuscript published in Nature,Schroer et al.discovered that platelets and in particular platelet derived Pf-4(CXCL4)are a novel factor,which can rejuvenate the mammalian neuronal system.1 These findings have the potential to trigger an entire new field of research opening new platelet-derived candidate effector molecules for supporting regeneration.

关键词： supporting platelets finding

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 utilities.Dissolved gas analysis(DGA)is frequently used for this purpose.However,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of degradation.Also,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault identification.Additionally,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to resources.Therefore,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 oil.The inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°Cmperaturefted especially for serving the simulation processes inside the laboratory for both types of inception faults.Subsequently,six samples of pure paraffinic mineral oil were taken to be degraded in the laboratory.following 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 case.After that,the fTIR analysis was initially verified utilising the DGA method.Then,for further affirmation,the dielectric dissipation factor(DDf)for all samples was measured.In 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

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 casting.This film was used as supporting material for glucose oxidase(GOx)to sensitize a glucose biosensor.ZnO nanoparticles have been prepared via the green route using olive leaves extract as a reductant.ZnO/Ppy nanocomposite has been synthesized by a simple in-situ chemical oxidative polymerization of pyrrole(Py)monomer using ferric chloride(feCl3)as an oxidizing agent.The 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 glucose.Current measurements proved the suitability and the high sensitivity of the constructed biosensor for the detection of glucose levels in different samples.The performance of the prepared biosensor has been assessed by measuring and comparing glucose concentrations up to 800 ppm.The 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