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Research in Astronomy and Astrophysics 2024年第9期24卷 7-27页

作者： Hakim Luthfi Malasan Bakuh Danang Setyo Budi department of Astronomy Faculty of Mathematics and Natural SciencesInstitut Teknologi BandungBandung 40132Indonesia Bosscha Observatory Institut Teknologi BandungLembang 40391Indonesia Master Program in Astronomy Faculty of Mathematics and Natural SciencesInstitut Teknologi BandungJl.Ganesha No.10Bandung 40132Indonesia

We present optical spectra of 10 Galactic Wolf-Rayet(WR)stars that consist of five WN and five WC *** optical observation was conducted using a low-resolution spectrograph NEO-R1000(λ/Δλ~1000)at GAO-ITB RTS(27.94 cm,F/10.0),Bosscha Observatory,*** implemented stellar atmosphere Postdam Wolf-Rayet(PoWR)grid modeling to derive stellar *** normalized optical spectrum can be used to find the best model from the available PoWR grid,then we could derive stellar temperature and transformation *** derive luminosity,stellar radius and color excess,we conducted a Spectral Energy Distribution(SED)analysis with additional data on the near-ultraviolet spectrum from the International Ultraviolet Explorer(IUE)database,and UBV and 2MASS JHK broadband filter *** analysis to derive asymptotic terminal wind velocity was conducted from the P-Cygni profile analysis of the high-resolution IUE ultraviolet *** previously derived parameters,we could determine the mass loss rate of the WR ***,we compared our results with previous work that used PoWR code and the differences are not more than 20%.We conclude that the PoWR spectral grid is sufficient to derive WR stellar parameters quickly and could provide more accurate initial parameter input to the PoWR program code.

关键词： stars:massive stars:mass-loss stars:Wolf-Rayet stars:atmospheres stars:winds outflows

Stability analysis of a fractional-order monkeypox epidemic model with quarantine and hospitalization

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Journal of Biosafety and Biosecurity 2024年第1期6卷 34-50页

作者： Raqqasyi R.Musafir Agus Suryanto Isnani Darti Trisilowati department of Mathematics Faculty of Mathematics and Natural SciencesUniversity of BrawijayaJl.VeteranMalang 65145Indonesia

The monkeypox epidemic has become a global health issue due to its rapid transmission involving nonhuman-to-human transmission in nonendemic *** actions,such as quarantine,vaccination,and hospitalization,have been implemented by worldwide *** the relatively high cost and strict implementation of vaccination,our focus lies on quarantine and *** this paper,we study the monkeypox epidemic involving quarantine and hospitalization through fractionalorder mathematical *** proposed model considers six classes of human populations(susceptible,exposed,infected,quarantined,hospitalized,and recovered)and three classes of nonhuman populations(susceptible,exposed,and infected).The basic properties of the model have been investigated,and its equilibrium points have been obtained,namely monkeypox-free,nonhuman-free endemic,and *** have derived the basic reproduction numbers for human-to-human and nonhuman-tononhuman transmissions,denoted as R0h and R0n *** existence and stability(both locally and globally)of each equilibrium point depend on R0h and R0n relative to *** performed calibration and forecasting of the model on the weekly monkeypox case data of the human population in the United States of America from June 1 to September 23,*** findings indicate that the fractional-order model shows better calibration and forecasting compared to the corresponding firstorder model based on the root mean square ***,the best-fitting model calibration indicates R0=maxfR0h;R0ng>1,suggesting the potential for endemic conditions in ***,the best forecasting shows R0<1,possibly due to various policies such as *** the relative cost and stringency of vaccination implementation for monkeypox control,we perform numerical simulations and sensitivity analyses on the basic reproduction number,particularly focusing on the impact of quarantine and hospitalization *** and

关键词： Fractional-order model Monkeypox Stability analysis Quarantine Hospitalization

Characterization of the infectivity of an Indonesian Zika virus strain in mammalian cell lines

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Asian Pacific Journal of Tropical Biomedicine 2024年第5期14卷 215-224页

作者： Justus Thomas Obiajulu Sievers Anom Bowolaksono R.Tedjo Sasmono Graduate School of Biology Department of BiologyFaculty of Mathematics and Natural SciencesUniversitas IndonesiaDepok 16424Indonesia Eijkman Research Center for Molecular Biology National Research and Innovation AgencyCibinong 16911Indonesia Cellular and Molecular Mechanisms in Biological System Research Group Department of BiologyFaculty of Mathematics and Natural SciencesUniversitas IndonesiaDepok 16424Indonesia

Objective:To characterize the infection patterns and growth characteristics of the Zika virus(ZIKV)strain JMB-185 from Indonesia in various mammalian cell ***:ZIKV was grown in human(A549,HEK293,HepG2,Huh7,Jurkat,and THP-1)and non-human mammalian(RAW264.7,Vero,and Vero76)cell *** replication kinetics were measured using plaque assay,while intra-and extracellular viral RNA concentrations were assessed using *** cytometry was used to quantify the infected cells and cell viability was measured using an MTT *** ability of ZIKV to infect cell lines was visualized using a fluorescence immunostaining ***:This ZIKV strain preferentially infected the lung,kidney,and liver cell lines A549,HEK293,Huh7,Vero,and Vero76,but not the immune cells Jurkat,RAW264.7,and *** contrast,the ZIKV showed no sign of infection in HepG2 cells,while maintaining viral titer over 3 days post-infection,with no infection recorded in immunostaining,no increase in viral RNA,and no indication of cell ***:The Indonesian ZIKV strain has a similar infection profile as other strains,except for its poor infectivity on HepG2 *** on the growth characteristics of Indonesia ZIKV will help expand our understanding of the biology of ZIKV which will be useful for various applications including antiviral discovery.

关键词： Zika virus Infectivity Replication Cell lines In vitro

Regulating interfacial stability of SiO_(x) anode with fluoride-abundant solid–electrolyte interphase by fluorine-functionalized additive

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Rare Metals 2024年第2期43卷 671-681页

作者： Subin Lee Taeeun Yim Advanced Batteries Laboratory Department of ChemistryIncheon National UniversityIncheon22012Republic of Korea Research Institute of Basic sciences College of Natural ScienceIncheon National UniversityIncheon22012Republic of Korea

Silicon oxide(SiO_(x))has received remarkable attention as a next-generation battery material;however,the sudden decrease in the cycling retention constitutes a significant challenge in facilitating its ***(2,2,2-trifluoroethyl)phosphite(TTFP),which can control parasitic reactions such as the pulverization of SiO_(x)anode materials and electrolyte decomposition,has been proposed to improve the lifespan of the *** electrochemical reduction of TTFP results in solid-electrolyte interphase(SEI)layers that are mainly composed of LiF,which occur at a higher potential than the working potential of the SiO_(x)anode and carbonate-based *** electrolyte with TTFP exhibited a substantial improvement in cycling retention after 100 cycles,whereas the standard electrolyte showed acutely decreased *** thickness of the SiO_(x)anode with TTFP also changed only slightly without any considerable delamination spots,whereas the SiO_(x)anode without TTFP was prominently deformed by an enormous volume expansion with several internal *** cycled SiO_(x)anode with TTFP exhibited less increase in resistance after cycling than that in the absence of TTFP,in addition to fewer decomposition adducts in corresponding X-ray photoelectron spectroscopy(XPS)analyses between the cycled SiO_(x)*** results demonstrate that TTFP formed SEI layers at the SiO_(x)interface,which substantially reduced the pulverization of the SiO_(x)anode materials;in addition,electrolyte decomposition at the interface decreased,which led to improved cycling retention.

关键词： Lithium-ion batteries(LIBs) Silicon oxide anode Electrolyte Additive Solid-electrolyte interphases(SEI) Tris(2,2,2-trifluoroethyl)phosphite

Optimizing Household Wastes (Rice, Vegetables, and Fruit) as an Environmentally Friendly Electricity Generator

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Journal of Renewable Materials 2024年第2期12卷 275-284页

作者： Deni Ainur Rokhim Isma Yanti Vitarisma Sumari Sumari Yudhi Utomo Muhammad Roy Asrori department of Chemistry Faculty of Mathematics and Natural SciencesUniversitas Negeri MalangMalang65145Indonesia Chemistry and PKWU SMAN 3 SidoarjoSidoarjo61215Indonesia

The high consumption of electricity and issues related to fossil energy have triggered an increase in energy prices and the scarcity of fossil ***,many researchers are seeking alternative energy *** potential technology,the Microbial Fuel Cell(MFC)based on rice,vegetable,and fruit wastes,can convert chemical energy into electrical *** study aims to determine the potency of rice,vegetable,and fruit waste assisted by Cu/Mg electrodes as a generator of *** method used was a laboratory experiment,including the following steps:electrode preparation,waste sample preparation,incubation of the waste samples,construction of a reactor using rice,vegetable,and fruit waste as a source of electricity,and *** tests included measuring electrical conductivity,electric current,voltage,current density,and power *** on the test results,the maximum current and voltage values for the fruit waste samples were 5.53 V and 11.5 mA,respectively,with a current density of 2.300 mA/cm^(2) and a power density of 12.719 mW/cm^(2).The results indicate the potential for a future *** next step in development involves determining the optimum conditions for utilizing of rice,vegetable,and fruit *** results of the electrical conductivity test on rice,vegetable,and fruit waste samples were 1.51,2.88,and 3.98 mS,respectively,with the highest electrical conductivity value found in the fruit waste sample.

关键词： Electrical energy fruit waste rice waste vegetable waste

Spirooxindoles:Recent report of green synthesis approach

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Green Synthesis and Catalysis 2024年第1期5卷 1-13页

作者： Agus Rimus Liandi Antonius Herry Cahyana Diva Naufal Alfariza Rahma Nuraini Renita Wulan Sari Tio Putra Wendari department of Chemistry Faculty of Science and TechnologyUniversitas Islam Negeri Syarif Hidayatullah JakartaTangerang Selatan 15412Indonesia department of Chemistry Faculty of Mathematics and Natural SciencesUniversitas IndonesiaDepok 16424Indonesia department of Chemistry Faculty of Mathematics and Natural SciencesUniversitas AndalasPadang 25163Indonesia

Spirooxindole is a compound with a unique framework and broad bioactivities in *** this study,we have reviewed various approaches or methods in synthesizing spirooxindole derivatives focused on green *** of spirooxindoles is mainly carried out through multicomponent reactions combined with various green approaches such as the use of heterogeneous catalysts(nano-sized,magnetic,metal-complex,and metal-organic framework catalysts),deep eutectic solvent,solvent-free reactions,catalyst-free reactions,as well as the use of ultrasonic and microwaves *** green method is carried out in addition to obtaining high yields,it also offers reductions in the use of hazardous chemicals,energy use,purification processes,and waste *** a result,green synthesis methods in the synthesis of spirooxindole derivatives are more environmentally friendly.

关键词： Spirooxindoles Green synthesis Catalysis Nanoparticle Ultrasonic irradiation

A stable implicit nodal integration-based particle finite element method(N-PFEM)for modelling saturated soil dynamics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2172-2183页

作者： Liang Wang Xue Zhang Jingjing Meng Qinghua Lei department of Earth sciences ETH ZürichZürich8092Switzerland department of Civil Engineering and Industrial Design University of LiverpoolLiverpoolL693BXUK department of Civil Environmental and Natural Resources EngineeringLuleåUniversity of TechnologyLuleå97187Sweden department of Earth sciences Uppsala UniversityUppsala75105Sweden

In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated *** approach incorporates the nodal integration technique into a generalised Hellinger-Reissner(HR)variational principle,creating an implicit PFEM *** mitigate the volumetric locking issue in low-order elements,we employ a node-based strain smoothing *** discretising field variables at the centre of smoothing cells,we achieve nodal integration over cells,eliminating the need for sophisticated mapping operations after re-meshing in the *** express the discretised governing equations as a min-max optimisation problem,which is further reformulated as a standard second-order cone programming(SOCP)***,pore water pressure,and displacements are simultaneously determined using the advanced primal-dual interior point ***,our numerical model offers improved accuracy for stresses and pore water pressure compared to the displacement-based PFEM *** experiments demonstrate that the N-PFEM efficiently captures both transient and long-term hydro-mechanical behaviour of saturated soils with high accuracy,obviating the need for stabilisation or regularisation techniques commonly employed in other nodal integration-based PFEM *** work holds significant implications for the development of robust and accurate numerical tools for studying saturated soil dynamics.

关键词： Particle finite element method Nodal integration Dynamic saturated media Second-order cone programming(SOCP)

Facile semisynthesis of histone H3 enables nucleosome probes for investigation of histone H_(3)K79 modifications

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Chinese Chemical Letters 2024年第10期35卷 321-324页

作者： Kun Zou Yihang Xiao jinyu Yang Mingxuan Wu department of Chemistry Zhejiang UniversityHangzhou 310027China department of Chemistry School of ScienceWestlake UniversityHangzhou 310030China Institute of natural sciences Westlake Institute for Advanced StudyHangzhou 310024China

Histone H3K79 modifications are essential to regulate chromatin structure and gene transcription,but understanding of the molecular mechanisms is *** H3K79 is at globular domain,short histone peptide cannot mimic H3K79 in ***,reconstituted nucleosome-based chemical tools are ideally used to investigate H3K79 *** consequence,H3K79-modified histone H3 with additional chemical handles are required,but such synthesis is challenging and *** we report a facile semisynthesis method that enables multifunctional histone H3 readily available.H3K79-containing fragment is short for straight peptide synthesis that was later ligated to recombinant expressed H3 fragments for full-length product in large *** a result,nucleosomes with H3K79 modifications as well as photo-reactive group and affinity tag were obtained to investigate potential binding *** believe this method that enhances synthetic accessibility of nucleosome probes will accelerate understanding of the underexplored H3K79 modifications.

关键词： Histone H3K79 modifications Methylation Succinylation Semisynthesis Nucleosome probes

An eikonal equation-based earthquake location method by inversion of multiple phase arrivals

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Science China Earth sciences 2024年第6期67卷 1802-1817页

作者： Gaoyue LAO Dinghui YANG Shaolin LIU Guiju DONG Wenshuai WANG Kui LIU National Institute of natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China School of Earth sciences Yunnan UniversityKunming 650091China department of Mathematical sciences Tsinghua UniversityBeijing 100084China School of Mathematics and Statistics Ningxia UniversityYinchuan 750021China

The precise determination of earthquake location is the fundamental basis in seismological community,and is crucial for analyzing seismic activity and performing seismic *** arrivals are generally used to practically determine earthquake ***,first-arrival traveltimes are not sensitive to focal ***,they cannot accurately constrain focal *** improve the accuracy,researchers have analyzed the depth phases of earthquake *** traveltimes of depth phases are sensitive to focal depths,and the joint inversion of depth phases and direct phases can be implemented to potentially obtain accurate earthquake ***,researchers can determine earthquake locations in layered *** layered models can only represent the first-order feature of subsurface structures,the advantages of joint inversion are not fully explored if layered models are *** resolve the issue of current joint inversions,we use the traveltimes of three seismic phases to determine earthquake locations in heterogeneous *** three seismic phases used in this study are the first P-,sPg-and *** calculate the traveltimes of the three seismic phases by solving an eikonal equation with an upwind difference scheme and use the traveltimes to determine earthquake *** verify the accuracy of the earthquake location method by the inversion of three seismic phases,we take the 2021 M_(S)6.4 Yangbi,Yunnan earthquake as an example and locate this earthquake using synthetic and real seismic *** tests demonstrate that the eikonal equation-based earthquake location method,which involves the inversion of multiple phase arrivals,can effectively improve earthquake location accuracy.

关键词： Earthquake location Eikonal equation Fast marching method Heterogeneous model

Pulsed laser interference patterning of transition-metal carbides for stable alkaline water electrolysis kinetics

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Carbon Energy 2024年第5期6卷 65-80页

作者： Yewon Oh Jayaraman Theerthagiri Ahreum Min Cheol Joo Moon Yiseul Yu Myong Yong Choi department of Chemistry(BK21 FOUR) Research Institute of Natural SciencesGyeongsang National UniversityJinjuRepublic of Korea Core−Facility Center for Photochemistry and Nanomaterials Gyeongsang National UniversityJinjuRepublic of Korea

We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed laser ablation of Co,Fe,Ti,and Mo metals in *** interaction between carbon s-p-orbitals and metal d-orbitals causes a redistribution of valence structure through charge transfer,leading to the formation of surface defects as observed by X-ray photoelectron *** defects influence the evolved TMCs,making them effective for hydrogen and oxygen evolution reactions(HER and OER)in an alkaline ***_(3)C with more oxygen affinity promoted CoO(OH)intermediates,and the electrochemical surface oxidation to Co_(3)O_(4)was captured via in situ/operando electrochemical Raman probes,increasing the number of active sites for OER *** with more d-vacancies exhibits strong hydrogen binding,promoting HER kinetics,whereas Fe_(3)C and TiC with more defect states to trap charge carriers may hinder both OER and HER *** results show that the assembled membrane-less electrolyzer with Co_(3)C∥Co_(3)C and MoC∥MoC electrodes requires~2.01 and 1.99 V,respectively,to deliver a 10 mA cm−2 with excellent electrochemical and structural *** addition,the ascertained pulsed laser synthesis mechanism and unit-cell packing relations will open up sustainable pathways for obtaining highly stable electrocatalysts for electrolyzers.

关键词： acetone H_(2)and O_(2)evolution reactions pulsed laser ablation surface defects transition-metal carbides water electrolyzer