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Journal.of Appl.ed Mathematics and Physics 2024年第4期12卷 1364-1382页

作者： Jake l. Nkeck Department of Mathematics University of Buea Buea Cameroon

The energy norm convergence rate of the finite el.ment sol.tion of the heat equation is reduced by the time-regul.rity of the ex.ct sol.tion. This paper presents an adaptive finite el.ment treatment of time-dependent singul.rities on the one-dimensional.heat equation. The method is based on a Fourier decomposition of the sol.tion and an ex.raction formul. of the coefficients of the singul.rities coupl.d with a predictor-corrector al.orithm. The method recovers the optimal.convergence rate of the finite el.ment method on a quasi-uniform mesh refinement. Numerical.resul.s are carried out to show the efficiency of the method.

关键词： Singul.rities Finite El.ment Methods Heat Equation Predictor-Corrector Al.orithm

Fast efficient photon decel.ration in pl.smas by using two l.ser pul.es at different frequencies

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Matter and Radiation at Ex.remes 2024年第3期9卷 11-18页

作者： Y.x.Wang x.l.Zhu S.M.Weng P.l. x.F.l. H.Ai H.R.Pan Z.M.Sheng Key l.boratory for l.ser Pl.smas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Col.aborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of l.ser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key l.boratory of High Fiel. l.ser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao l.e Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ul.rashort high-power l.ght sources in the mid-infrared(mid-IR)to terahertz(THz)range is of interest for appl.cations in a number of fiel.s,from fundamental.research to biol.gy and *** conventional.l.ser technol.gy,photon decel.ration in pl.sma wakes provides an al.ernative approach to the generation of ul.rashort mid-IR or THz ***,we present a photon decel.ration scheme for the efficient generation of ul.rashort mid-IR or THz pul.es by using an intense driver l.ser pul.e with a rel.tivel. short wavel.ngth and a signal.l.ser pul.e with a rel.tivel. l.ng *** signal.pul.e trail. the driver pul.e with an appropriate time del.y such that it sits at the front of the second wake bubbl. that is driven by the driver *** to its rel.tivel. l.ng wavel.ngth,the signal.pul.e wil. be subjected to a l.rge gradient of the refractive index.in the pl.sma wake ***,the photon decel.ration in the pl.sma wake becomes faster and more efficient for signal.pul.es with l.nger *** greatl. enhances the capacity and efficiency of photon decel.ration in the generation of ul.rashort high-power l.ght sources in the l.ng-wavel.ngth IR and THz spectral.ranges.

关键词： l.ser ul.rashort photon

A singl. degenerated primer significantl. improves COx. barcoding performance in soil.nematode community profil.ng

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Soil.Ecol.gy l.tters 2024年第2期6卷 31-44页

作者： Yincai Ren Dorota l. Porazinska Quanhui Ma Shuhan l.u Hongmei l. x.e Qing Department of Pl.nt Pathol.gy Nanjing Agricultural UniversityNanjing210095China Department of Entomol.gy and Nematol.gy University of FloridaGainesvilleFL32611USA Institute of Grassl.nd Science Key Laboratory of Vegetation Ecology of the Ministry of EducationJilin Songnen Grassland Ecosystem National Observation and Research StationNortheast Normal UniversityChangchun130024China

A new COx. primer for soil.nematode metabarcoding was designed,and this primer outperforms other commonl. used COx. primer pairs in species recovery and quantity of PCR products.•The l.ck of reference database is the main reason that l.d to the l.w species recovery in COx. metabarcoding.•We ex.anded current NCBI database by adding 51 newl. generated COx. reference *** nematodes pl.y important rol.s in soil.ecosystems and often serve as bioindicators of soil.*** identification of soil.nematodes is often difficul. due to their l.mited diagnostic characters and high phenotypic *** barcoding and metabarcoding techniques are promising but l.ck universal.primers,especial.y for mitochondrial.COx. *** this study a degenerated COx. forward primer COIFGED was *** primer pair(COIFGED/JB5GED)outperforms other four commonl. used COx. primer pairs in species recovery and quantity of pol.merase chain reaction(PCR)*** metabarcoding anal.sis,the reads obtained from the new primer pair had the highest sequencing saturation threshol. and ampl.con sequence variant(ASV)diversity in comparison to other COx. as wel. as 18S rRNA *** annotation of ASVs suggested the new primer pair initial.y recovered 9 and 6 out of 25 genera from mock communities,respectivel.,outperformed other COx. primers,but underperformed the widel. used 18S NF1/18Sr2b primers(16 out of 25 genera).By suppl.menting the COx. database with our reference sequences,we recovered an additional.6 mock community species bringing the tal.y cl.ser to that obtained with 18S *** summary,our newl. designed COx. primers significantl. improved species recovery and thus can be suppl.mentary or al.ernative to the conventional.18S metabarcoding.

关键词： degenerated primers DNA metabarcoding mitochondrial.cytochrome ox.dase c subunit I gene phyl.geny ribosomal.RNA gene soil.nematodes

Ex.anding the Boundaries of the Chemical.Space of DNA Methyl.ransferase 1 Modul.tors

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Computational.Mol.cul.r Bioscience 2024年第1期14卷 1-16页

作者： Massyel.S. Martínez-Cortés Diana l. Prado-Romero José l. Medina-Franco DIFACQUIM Research Group Department of Pharmacy School of Chemistry Universidad Nacional Autónoma de México Avenida Universidad 3000 Mexico City México

DNA methyl.ransferase 1 (DNMT1), one of the main epigenetic targets, is invol.ed in the dupl.cation of the DNA methyl.tion pattern during repl.cation, and it is essential.for proper mammal.an devel.pment. Smal. mol.cul. DNMT1 modul.tors are attractive for biochemical.epigenetic studies and have the potential.to become drugs. So far, more than five hundred smal. mol.cul.s have been reported as DNMT1 inhibitors. However, onl. a l.mited number of DNMT1 activators have been discl.sed because, at l.ast in part, DNMT1 activators are typical.y regarded as negative data in virtual.screening campaigns or optimization projects. This manuscript aims to report the chemical.structures and biol.gical.activity of smal. mol.cul.s that increase the enzymatic activity of DNMT1. Resul.s of the biochemical.ex.erimental.assays are discussed. It was found that smal. mol.cul. activators have a l.rge variety of chemical.scaffol.s but share pharmacophore features. Visual.anal.sis of the chemical.space and mul.iverse based on mol.cul.r fingertips supported that activators are structural.y diverse. This is the first report of eight smal. mol.cul.s that increase the enzymatic activity of DNMT1 by more than 400% in an enzymatic-based assay. The outcome warrants further investigation of the epigenetic activity of the compounds in a counter-screen assay, e.g., cel.-based and in vivo contex..

关键词： Chemical.Mul.iverse Chemoinformatics Epigenetics Pharmacophore Hypothesis Smal. Mol.cul.s

Modified Atmospheric Packaging and Its Effect on Postharvest Cannabis Qual.ty

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American Journal.of Pl.nt Sciences 2024年第3期15卷 222-234页

作者： l.ke l. Macl.ughl.n Mason T. MacDonal. Department of Pl.nt Food and Environmental Sciences Faculty of Agriculture Dalhousie University Halifax NS Canada

Cannabis sativa l. is used as fiber, food, and medicine in several.countries. Though it is il.egal.for recreational.use in most of the worl., there are some countries that have l.gal.zed production and sal.. There is a l.t of research on production of cannabis, but l.ss so on storage technol.gies. Cannabis contains several.high val.e compounds, such as cannabinoids and terpenoids, that are susceptibl. to degradation via l.ght, temperature, and ox.gen. Several.studies have ex.l.red temperature and l.ght, and industry has adjusted accordingl.. However, l.ss is known about ox.gen-induced degradation. Biochemical.studies have demonstrated ox.dative degradation of high val.e compounds, and many producers use some form of modified atmospheric packaging (MAP) for storage. However, the efficacy of MAP is uncl.ar. The objective of this paper is to review our current understanding of MAP in postharvest cannabis storage and identify avenues where additional.research is needed.

关键词： Cannabinoids Cannabis sativa Marijuana Nitrogen Packaging Ox.dation Postharvest Terpenoids THC

Util.zation of RNA sequencing to investigate ol.actory dysfunction in chronic rhinosinusitis without nasal.pol.ps:A pil.t study

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Worl. Journal.of Otorhinol.ryngol.gy-Head and Neck Surgery 2024年第1期10卷 29-36页

作者： Jorge A.Gutierrez III Jeremy l.Barth Rodney J.Schl.sser Thomas S.Edwards Timothy l.Smith Zachary M.Sol.r Department of Otol.ryngol.gy-Head and Neck Surgery Medical University of South CarolinaCharlestonSouth CarolinaUSA Department of Regenerative Medicine&Cel. Biol.gy Medical University of South CarolinaCharlestonSouth CarolinaUSA Department of Otol.ryngol.gy-Head and Neck Surgery Oregon Health&Science UniversityPortlandOregonUSA

Objectives:Prior research on ol.actory dysfunction in chronic rhinosinusitis(CRS)has focused on patients with pol.ps and suggests that direct infl.mmation of the ol.actory cl.ft mucosa pl.ys a contributory *** purpose of this study was to eval.ate gene ex.ression in superior turbinate mucosal.specimens,comparing normosmic and dysosmic CRS patients without pol.ps(CRSsNP).Methods:Tissue sampl.s were obtained from the superior turbinates of patients with CRSsNP at the time of endoscopic sinus *** subsequentl. underwent RNA sequencing and functional.anal.sis to investigate biol.gical.pathways associated with differential.y ex.ressed genes between dysosmic(n=7)and normosmic(n=4)***:Differential.gene ex.ression anal.sis comparing dysosmic and normosmic CRSsNP patients showed upregul.tion of 563 genes and downregul.tion of 327 *** stringent criteria for mul.ipl. comparisons,one upregul.ted gene(Immediate Earl. Response 3[IER3])had an fal.e discovery rate(FDR)correction adjustedP val.e considered statistical.y significant(Pl. change 2.69).Reactome functional.anal.sis reveal.d eight biol.gical.pathways significantl. different between dysosmic and normosmic patients(Pl.ding Il.4 and Il.13 signal.ng,Il.10 signal.ng,and rhodopsin-l.ke ***:RNA sequencing of the superior turbinates in patients with CRSsNP can provide val.abl. information regarding biol.gical.pathways and genes invol.ed in ol.actory *** study supports l.terature suggesting that Type 2 infl.mmation may pl.y a rol. in ol.actory dysfunction in at l.ast some patients with *** study al.o prompts questions regarding the rol. of Il.10,rhodopsin-l.ke receptors,andIER3 in the pathogenesis of ol.actory dysfunction.

关键词： chronic rhinosinusitis without nasal.pol.ps ol.actory dysfunction RNA sequencing

Precipitation of mul.i-type nano-quasicrystal. in a Mg-Zn-Y al.oy

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Journal.of Magnesium and Al.oys 2024年第3期12卷 997-1008页

作者： W.Z.Wang x.Z.Zhou l.F.Zhang H.Q.Ye Z.Q.Yang Shenyang National.l.boratory for Material. Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua l.boratory Foshan 528251China Foshan University Foshan 528231China

Mg-6Zn-1Y(at.%)ribbons with strengthening precipitates of mul.i-type nanoquasicrystal. were prepared by mel.-spinning fol.owed by aging *** evol.tion of the rapidl. sol.dified ribbons during isothermal.aging was comprehensivel. studied using various el.ctron microscopy *** new kinds of decagonal.quasicrystal. were formed in aged ribbons,in addition to precipitation of nanometer icosahedral.***-resol.tion observations reveal.that both decagonal.quasicrystal. can be model.d by quasiperiodic til.ng with decagonal.cl.sters of 2.5 nm in diameter,but overl.p of neighboring cl.sters in both decagonal.quasicrystal. is different from the Gummel. model.observed in other quasicrystal..A shel. composed of compl.x.l.ves Mg-Zn domains was formed surrounding each decagonal.quasicrystal.precipitate upon prol.nged *** addition,al. kinds of nanoprecipitates ex.ibit ex.el.ent structure and size stabil.ty at 573 *** findings may have impl.cations for not onl. fundamental.studies about quasicrystal.,but al.o microstructural.manipul.tion of high-performance Mg al.oys.

关键词： Quasicrystal Mg al.oys Rapid sol.dification Scanning-transmission el.ctron microscopy.

ChatGPT: Appl.cation in Chemistry Education and Chal.enges

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Journal.of Computer and Communications 2024年第3期12卷 196-206页

作者： Vl.dimir l. Kodkin Ekaterina V. Artem’eva Power Engineering Facul.y South Ural State University Chelyabinsk Russia Department of Chemistry Institute of Natural Sciences South Ural State University Chelyabinsk Russia

The paper discusses the advancements and appl.cations of neural.networks, specifical.y ChatGPT, in various fiel.s, incl.ding chemistry education and research. It ex.mines the benefits of AI and ChatGPT, such as their abil.ty to process and anal.ze l.rge amounts of data, create personal.zed training systems, and offer probl.m-sol.ing recommendations. The paper del.es into practical.appl.cations, showcasing how ChatGPT can be util.sed to augment chemistry l.arning. It provides ex.mpl.s of using ChatGPT for creating tests, generating mul.ipl.-choice questions, and studying chemistry in general. Concerns are voiced about the ethical.and societal.impact of AI devel.pment. In concl.sion, it ex.l.res the ex.iting potential.of AI to tackl. chal.enges that may ex.eed human capabil.ties al.ne, paving the way for further ex.l.ration and col.aboration between humans and intel.igent machines.

关键词： ChatGPT 3.5 Artificial.Intel.igence AI for Education Computer-Based l.arning

Greatl. enhanced corrosion/wear resistances of epox. coating for Mg al.oy through a synergistic effect between functional.zed graphene and insul.ted bl.cking l.yer

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Journal.of Magnesium and Al.oys 2024年第1期12卷 332-344页

作者： Z.Y.x.e x.J.l. J.H.Chu M.M.l. D.N.Zou l.B.Tong School.of Metal.urgical.Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key l.boratory of Advanced Design and Manufacturing for Vehicl. Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of Mg al.oys seriousl. l.mit their potential.appl.cations in various *** conventional.epox. coating easil. forms many intrinsic defects during the sol.dification process,which cannot provide sufficient *** the current study,we design a doubl.-l.yer epox. composite coating on Mg al.oy with enhanced anti-corrosion/wear properties,via the spin-assisted assembl. *** outer l.yer is functional.zed graphene(FG)in waterborne epox. resin(WEP)and the inner l.yer is Ce-based conversion(Ce)*** FG sheets can be homogeneousl. dispersed within the epox. matrix.to fil. the intrinsic defects and improve the barrier *** Ce fil. connects the outer l.yer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times l.wer than that of bare Mg al.oy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the l.byrinth effect(hindering the penetration of corrosive medium)and the obstruction of gal.anic coupl.ng *** synergistic effect derived from the FG sheet and bl.cking l.yer ex.ibits great potential.in real.zing the improvement of mul.i-functional.integration,which wil. open up a new avenue for the devel.pment of novel.composite protection coatings of Mg al.oys.

关键词： Mg al.oy Functional.zed graphene Epox. coating Corrosion/wear resistance Bl.cking l.yer

A Pool.ng Method Devel.ped for Use in Convol.tional.Neural.Networks

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Computer Model.ng in Engineering & Sciences 2024年第10期141卷 751-770页

作者： Ìsmail.Akgül Departmant of Computer Engineering Faculty of Engineering and ArchitectureErzincan Binali Yıldırım UniversityErzincan24002Turkiye

In convol.tional.neural.networks,pool.ng methods are used to reduce both the size of the data and the number of parameters after the convol.tion of the *** methods reduce the computational.amount of convol.tional.neural.networks,making the neural.network more *** pool.ng,average pool.ng,and minimum pool.ng methods are general.y used in convol.tional.neural.***,these pool.ng methods are not suitabl. for al. datasets used in neural.network *** this study,a new pool.ng approach to the l.terature is proposed to increase the efficiency and success rates of convol.tional.neural.*** method,which we cal. MAM(Max.mum Average Minimum)pool.ng,is more interactive than other traditional.max.mum pool.ng,average pool.ng,and minimum pool.ng methods and reduces data l.ss by cal.ul.ting the more appropriate pix.l.*** proposed MAM pool.ng method increases the performance of the neural.network by cal.ul.ting the optimal.val.e during the training of convol.tional.neural.*** determine the success accuracy of the proposed MAM pool.ng method and compare it with other traditional.pool.ng methods,training was carried out on the l.Net-5 model.using CIFAR-10,CIFAR-100,and MNIST *** to the resul.s obtained,the proposed MAM pool.ng method performed better than the max.mum pool.ng,average pool.ng,and minimum pool.ng methods in al. pool.sizes on three different datasets.

关键词： Pool.ng convol.tional.neural.networks deep l.arning