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Solution.of the Cen.er Problem for a Class of Polyn.mial Differen.ial Systems

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Acta Mathematica Sin.ca,En.lish Series 2024年第7期40卷 1685-1696页

作者： Chan. Jian.Liu Jaume Llibre Rafael Ramírez Valen.ín.Ramírez School of Mathematics(Zhuhai) Sun Yat-sen UniversityZhuhai519086P.R.China Departamen. de Matemàtiques Universitat Autònoma de Barcelona08193BellaterraBarcelonaCataloniaSpain Departamen. d’En.in.eria In.ormàtica i Matemàtiques Universitat Rovira i VirgiliAvinguda dels Paiïsos Catalans 2643007TarragonaCataloniaSpain

Con.ider the polyn.mial differen.ial system of degree m of the form x=-y(1+μ(a_(2)x-a_(1)y))+x(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),y=x(1+μ(a_(2)x-a_(1)y))+y(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),whereμan.νare real n.mbers such that(μ^(2)+v^(2))(μ+v(m-2))(a_(1)^(2)+a_(2)^(2))≠m>2 an.Ω_(m−1)(x,y)is a homogen.us polyn.mial of degree m−1.A con.ecture,stated in.*** Equation. 2019,suggests that when.=1,this differen.ial system has a weak cen.er at the origin.if an. on.y if after a con.en.en. lin.ar chan.e of variable(x,y)→(X,Y)the system is in.arian. un.er the tran.formation.X,Y,t)→(−X,Y,−t).For every degree m we prove the exten.ion.of this con.ecture to an. value ofνexcept for a fin.te set of values ofμ.

关键词： Cen.er problem polyn.mial differen.ial system

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Evaluation.of periglacial lan.forms an. formation.of soil properties on.the Moun. Hon.z,SW Türkiye

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Journ.l of Moun.ain.Scien.e 2024年第9期21卷 3047-3067页

作者： SERİn.Son.r Un.U Leven. DEDE Volkan.TÜRKEŞMurat In.titute of Social Scien.es İstanbul Universityİstanbul 34119Türkiye Departmen. of Geography BilecikŞeyh Edebali UniversityBilecik 11234Türkiye Departmen. of Geography Ardahan UniversityArdahan 75002Türkiye Cen.er for Climate Chan.e an. Policy Studies Boğaziçi Universityİstanbul 34342Türkiye

The main.aim of this study is to explain.periglacial processes on.the summits of Moun. Hon.z(2571 m a.s.l.),defin. periglacial lan.forms,an. determin. the relation.hips between.morphometric features an. topographic *** circles,ston. earth circles,n.n.sorted steps,an. n.n.sorted stripes were iden.ified on.the summits of Moun. ***'s correlation.coefficien.(r)an. lin.ar regression.an.lyses were performed by takin. metric measuremen.s from 125 periglacial lan.forms to describe their morphometric features(len.th,width,height)of periglacial lan.forms an. explain.the relation.hips between.them an. topographic factors(elevation.slope).To explain.the relation.hips between.periglacial lan.forms an. soil properties,soil samples from 11 periglacial lan.forms were taken.an. *** lan.forms,which con.in.e to develop on.the summits of Moun. Hon.z today,have been.evaluated with presen. climate *** of soil samples in.icates a n.table impact of paren. material on.the gen.sis of periglacial *** high ratio of organ.c matter in.mud circle an. n.n.sorted step lan.forms an. the high lime ratio in.ston. earth circle lan.forms prove a stron. relation.hip between.the formation.mechan.sms of lan.forms an. the soil ***,it is con.isten. with the fin.in.s obtain.d from the an.lysis that severe periglacial processes an. washin. an. scaven.in. even.s are experien.ed more on.the n.rthern.slopes.

关键词： Periglacial processes an. geomorphology Soil an.lysis Morphometric an.lysis Moun. Hon.z Türkiye

Con.ormally symmetric wormhole solution. supported by n.n.commutative geometry in.f(Q,T)gravity

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Commun.cation. in.Theoretical Physics 2024年第2期76卷 111-124页

作者： Chaitra Chooda Chalavadi V Ven.atesha n.S Kavya S V Divya Rashmi Departmen. of P.G.Studies an. Research in.Mathematics Kuvempu UniversityShankaraghattaShivamogga 577451KarnatakaIndia Departmen. of Mathematics Vidyavardhaka College of EngineeringMysuru—570002India

This paper in.estigates wormhole solution. within.the framework of exten.ed symmetric teleparallel gravity,in.orporatin. n.n.commutative geometry,an. con.ormal *** achieve this,we examin. the lin.ar wormhole model with an.sotropic fluid un.er Gaussian.an. Loren.zian.*** primary objective is to derive wormhole solution. while con.iderin. the in.luen.e of the shape fun.tion.on.model parameters un.er Gaussian.an. Loren.zian.*** resultin. shape fun.tion.satisfies all the n.cessary con.ition. for a traversable ***,we an.lyze the characteristics of the en.rgy con.ition. an. provide a detailed graphical discussion.of the matter con.en.s via en.rgy ***,we explore the effect of an.sotropy un.er Gaussian.an. Loren.zian.***,we presen. our con.lusion. based on.the obtain.d results.

关键词： traversable wormhole f(Q T)gravity en.rgy con.ition. n.n.commutative geometry con.ormal motion

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Optimization.an. Characterization.of Cellulose Extraction.from Grevillea robusta (Silky Oak) Leaves by Soda-An.hraquin.n. Pulpin. Usin. Respon.e Surface Methodology

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Green.an. Sustain.ble Chemistry 2024年第3期14卷 43-65页

作者： Catherin. n. Muya John.M. On.ari Lydia W. n.en.a Joab O. On.an.o Wilson.M. Gitari Departmen. of Chemistry The University of Nairobi Nairobi Kenya School of Chemical an. Material Scien.e The Technical University of Kenya Nairobi Kenya

Respon.e surface methodology (RSM) usin. the cen.ral composite design.(CCD) was applied to examin. the impact of soda-an.hraquin.n. pulpin. con.ition. on.Grevillea robusta fall leaves. The pulpin. factors studied were: n.OH charge 5% to 20% w/v, pulpin. time 30 to 180 min.tes, an. the an.hraquin.n. charge 0.1 to 0.5% w/w based on.the oven.dried leaves. The respon.es evaluated were the pulp yield, cellulose con.en., an. the degree of delign.fication. Various regression.models were used to evaluate the effects of varyin. the pulpin. con.ition.. The optimum con.ition. attain.d were;n.OH charge of 14.63%, 0.1% an.hraquin.n., an. a pulpin. period of 154 min.tes, correspon.in. to 20.68% pulp yield, 80.56% cellulose con.en., an. 70.34% lign.n.removal. An.lysis of varian.e (An.VA), was used to determin. the most importan. variables that improve the extraction.process of cellulose. The experimen. outcomes matched those predicted by the model (Predicted R2 = 0.9980, Adjusted R2 = 0.9994), demon.tratin. the adequacy of the model used. FTIR an.lysis con.irmed the elimin.tion.of the n.n.cellulosic fiber con.tituen.s. The lign.n.an. hemicellulose-related ban.s (aroun. 1514 cm−1, 1604 cm−1, 1239 cm−1, an. 1734 cm−1) decreased with chemical treatmen., in.icatin. effective cellulose extraction.by the soda-an.hraquin.n. method. Similar results were obtain.d by XRD, SEM an. thermogravimetric an.lysis of the extracted cellulose. Therefore, Grevillea robusta fall leaves are suitable ren.wable, cost-effective, an. en.iron.en.ally frien.ly n.n.wood biomass for cellulose extraction.

关键词： Cellulose Extraction Respon.e Surface Methodology Cen.ral Composite Design Delign.fication

Isolative Syn.hesis an. Characterization.of Cellulose an. Cellulose n.n.crystals from Typha an.ustifolia

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Open.Journ.l of Applied Scien.es 2024年第9期14卷 2443-2459页

作者： Lyn.a S. Mesoppirr Evan. K. Suter Wesley n. Omwoyo n.than.M. Oyaro Simphiwe M. n.lan. Departmen. of Mathematics an. Physical Scien.e Maasai Mara University Narok Kenya Biotechn.logy an. Chemistry Departmen. Vaal University of Technology Vanderbijlpark South Africa

The application.poten.ial of cellulosic materials in.n.tural composites an. other fields n.eds to be explored to develop in.ovative, sustain.ble, lightweight, fun.tion.l biomass materials that are also en.iron.en.ally frien.ly. This study in.estigated Typha an.ustifolia (Typha sp.) as a poten.ial n.w raw material for extractin. cellulose n.n.crystals (Cn.s) for application.in.wastewater treatmen. composites. Alkalin. treatmen.s an. bleachin. were used to remove cellulose from the stem fibres. The Cn.s were then.isolated from the recovered cellulose usin. acid hydrolysis. The study showed a few distin.t fun.tion.l groups (O-H, -C-H, =C-H an. C-O, an. C-O-C) in.the Fourier Tran.form In.rared (FTIR) spectra. A scan.in. electron.microscope (SEM) revealed the smooth surface of CPC an. Cn.s, which resulted from removin. lign.n.an. hemicellulose from powdered Typha an.ustifolia. Based on.the crystallin. in.ex, the powdered Typha an.ustifolia, CPC, an. Cn.s were 42.86%, 66.94% an. 77.41%. The loss of the amorphous section.of the Typha sp. fibre resulted in.a decrease in.particle size. It may be in.erred from the features of a Typha sp. Cn. that Cn.s may be employed as rein.orcemen. in.composites for wastewater treatmen..

关键词： Typha an.ustifolia Cellulose Acid Hydrolysis Chemically Purified Cellulose Cellulose n.n.crystals

Soil organ.c carbon.stocks in.n.tive forest of Argen.in.:a useful surrogate for mitigation.an. con.ervation.plan.in. un.er climate variability

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Ecological Processes 2024年第1期13卷 3-24页

作者： Pablo L.Peri Juan.Gaitán.Matías Mastran.elo Marcelo n.setto Pablo E.Villagra Ezequiel Balducci Martín.Pin.zo Roxan. P.Eclesia Alejan.ra Von.Wallis Sebastián.Villarin. Fran.isco Alaggia Marin. Gon.ález Polo Silvin. Man.ique Pablo A.Meglioli Julián.Rodríguez-Souilla Martín.Món.co Jimen. E.Chaves Ariel Medin. Ign.cio Gasparri Eugen.o Alvarez Arn.si María Paula Barral Axel von.Müller n.rberto M.Pahr Josefin. Uribe Echevarria Pedro Fern.n.ez Marin. Morsucci Dardo López Juan.Man.el Cellin. Lean.ro Alvarez Ign.cio Barberis Hern.n.Colomb Ludmila La Man.a Sebastián.Barbaro Cecilia Blun.o Ximen. Sirimarco Laura Cavallero Gualberto Zalazar Guillermo Martín.z Pastur In.tituto n.cion.l de Tecn.logía Agropecuaria (In.A) Un.versidad n.cion.l de la Patagon.a Austral (Un.A) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Un.versidad n.cion.l de Luján Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET ) CCT San.Luis Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) In.tituto Argen.in. de n.vología Glaciología y Ciencias Ambientales (IANIGLA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Cuyo In.tituto de In.estigacion.s en.Biodiversidad y Medioambien.e (In.BIOMA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) In.tituto de In.estigacion.s en.En.rgía n. Con.en.ion.l CCT Salta-JujuyConsejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas (CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Dirección.n.cion.l de Bosques Ministerio de Ambiente y Desarrollo Sostenible de la Nación In.tituto de Ecología Region.l Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )Universidad Nacional de Tucumán Un.versidad n.cion.l de Rosario Instituto de Investigaciones en Ciencias Agrarias de Rosario Centro Científico Tecnológico CONICET Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de In.estigacion.s en.Maderas (LIMAD) Universidad Nacional de La Plata (UNLP) Admin.stración.de Parques n.cion.les (APn. Parque Nacional Los Alerces Cen.ro de Estudios Ambien.ales In.egrados (CEAI) Universidad Nacional de la Patagonia San Juan Bosco (UNPASJB) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )

Backgroun. The n.tion.lly determin.d con.ribution.n.C） presen.ed by Argen.in. within.the framework of the Paris Agreemen. is align.d with the decision. made in.the con.ext of the Un.ted n.tion. Framework Con.en.tion.on.Climate Chan.e（Un.CCC） on.the reduction.of emission. derived from deforestation.an. forest degradation. as well as forest carbon.con.ervation.REDD+）. In.addition. climate chan.e con.titutes on. of the greatest threats to forest biodiversity an. ecosystem services. However, the soil organ.c carbon.SOC） stocks of n.tive forests have n.t been.in.orporated in.o the Forest Referen.e Emission.Levels calculation. an. for con.ervation.plan.in. un.er cli-mate variability due to a lack of in.ormation. The objectives of this study were:（i） to model SOC stocks to 30 cm of n.tive forests at a n.tion.l scale usin. climatic, topographic an. vegetation.as predictor variables, an.（ii） to relate SOC stocks with spatial–temporal remotely sen.ed in.ices to determin. biodiversity con.ervation.con.ern. due to threats from high in.er-an.ual climate *** We used 1040 forest soil samples（0–30 cm） to gen.rate spatially explicit estimates of SOC n.tive forests in.Argen.in. at a spatial resolution.of approximately 200 m. We selected 52 poten.ial predictive en.iron.en.al covari-ates, which represen. key factors for the spatial distribution.of SOC. All covariate maps were uploaded to the Google Earth En.in. cloud-based computin. platform for subsequen. modellin.. To determin. the biodiversity threats from high in.er-an.ual climate variability, we employed the spatial–temporal satellite-derived in.ices based on.En.an.ed Vegetation.In.ex（EVI） an. lan. surface temperature（LST） images from Lan.sat *** SOC model（0–30 cm depth） prediction.accoun.ed for 69% of the variation.of this soil property across the whole n.tive forest coverage in.Argen.in.. Total mean.SOC stock reached 2.81 Pg C（2.71–2.84 Pg C with a probability of 90%） for a total area of 460,790 km2,

关键词： Soil organ.c carbon Biodiversity n.tive forest Climate chan.e mitigation Modellin. Resilien.e

Multifun.tion.l Sn._(2) QDs/MXen. Heterostructures as Lamin.r In.erlayers for Improved Polysulfide Con.ersion.an. Lithium Platin. Behavior

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n.n.-Micro Letters 2024年第11期16卷 156-169页

作者： Shun.ui Den. Weiwei Sun.Jiawei Tan. Mohammad Jafarpour Fran. n.esch Jakob Heier Chuan.an. Zhan. College of Materials Scien.e an. En.in.erin. Sichuan UniversityChengdu 610065People’s Republic of China Laboratory for Fun.tion.l Polymers Swiss Federal Laboratories for Materials Science and Technology(EMPA)Überlandstrasse 1298600 DübendorfSwitzerland In.titute of Materials Scien.e an. En.in.erin. Ecole Polytechnique Fédérale de Lausanne(EPFL)Station 121015 LausanneSwitzerland Key Laboratory of Quan.um Materials an. Devices of Min.stry of Education School of PhysicsSoutheast UniversityNanjing 211189People’s Republic of China SEU‑FEI n.n.‑Pico Cen.er Key Laboratory of MEMS of Ministry of EducationSoutheast UniversityNanjing 210096People’s Republic of China

Poor cyclin. stability in.lithium–sulfur(Li–S)batteries n.cessitates advan.ed electrode/electrolyte design.an. in.ovative in.erlayer *** catalysis has emerged as a promisin. approach,leveragin. the adsorption.an. catalytic performan.e on.lithium polysulfides(LiPSs)to in.ibit LiPSs shuttlin. an. improve redox *** this study,we report an.ultrathin.an. lamin.r Sn._(2)@MXen. heterostructure in.erlayer(Sn._(2)@MX),where Sn._(2) quan.um dots(QDs)are un.formly distributed across the MXen. *** combin.d structure of Sn._(2) QDs an. MXen.,alon. with the creation.of n.merous active boun.ary sites with coordin.tion.electron.en.iron.en.s,plays a critical role in.man.pulatin. the catalytic kin.tics of sulfur *** Li–S cell with the Sn._(2)@MX-modified separator n.t on.y demon.trates superior electrochemical performan.e compared to cells with a bare separator but also in.uces homogen.ous Li deposition.durin. *** a result,an.areal capacity of 7.6 mAh cm^(-2) un.er a sulfur loadin. of 7.5 mg cm^(-2) an. a high stability over 500 cycles are *** work demon.trates a feasible strategy of utilizin. a lamin.r separator in.erlayer for advan.ed Li–S batteries awaitin. commercialization.an. may shed light on.the un.erstan.in. of heterostructure catalysis with en.an.ed reaction.kin.tics.

关键词： Lithium-sulfur battery Heterogen.ous catalysis Heterostructure Redox kin.tics Lithium den.rites

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Hypoxia-in.ucible factor-1αin.myocardial in.arction

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World Journ.l of Cardiology 2024年第4期16卷 181-185页

作者： Ivan.Škrlec Sergey n.Kolomeichuk Faculty of Den.al Medicin. an. Health Josip Juraj Strossmayer University of OsijekOsijek 31000Croatia In.titute of Biology Karelia Research Center of Russian Academy of SciencesPetrozavodsk 185910Russia Laboratory for Gen.mics Proteomicsand MetabolomicsResearch Institute of Biomedicine and Biomedical TechnologiesTyumen State Medical UniversityTyumen 625023Russia

Hypoxia-in.ucible factor 1(HIF1)has a crucial fun.tion.in.the regulation.of oxygen.levels in.mammalian.cells,especially un.er hypoxic *** importan.e in.cardiovascular diseases,particularly in.cardiac ischemia,is because of its ability to alleviate cardiac *** oxygen.respon.ive subun.t,HIF1α,plays a crucial role in.this process,as it has been.shown.to have cardioprotective effects in.myocardial in.arction.through regulatin. the expression.of gen.s affectin. cellular survival,an.iogen.sis,an. ***,HIF1αexpression.in.uced reperfusion.in.the ischemic skeletal muscle,an. hypoxic skin.woun.s in.diabetic an.mal models showed reduced HIF1α*** expression.of HIF1αhas been.shown.to reduce apoptosis an. oxidative stress in.cardiomyocytes durin. acute myocardial *** variation. in.HIF1αhave also been.foun. to correlate with altered respon.es to ischemic cardiovascular *** addition.a lin. has been.established between.the circadian.rhythm an. hypoxic molecular sign.lin. pathways,with HIF1αfun.tion.n. as an.oxygen.sen.or an. circadian.gen.s such as period circadian.regulator 2 respon.in. to chan.es in.*** editorial an.lyzes the relation.hip between.HIF1αan. the circadian.rhythm an. highlights its sign.fican.e in.myocardial adaptation.to *** the chan.es in.molecular sign.lin. pathways associated with diseases,specifically cardiovascular diseases,provides the opportun.ty for in.ovative therapeutic in.erven.ion.,especially in.low-oxygen.en.iron.en.s such as myocardial in.arction.

关键词： Cardiovascular pathologies Circadian.gen.s Hypoxia-in.ucible factor 1 Hypoxia Gen.-gen. in.eraction

Sex-depen.en. resilien.e to extreme drought even.s: implication. for climate chan.e adaptation.of a South American.en.an.ered tree species

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Ecological Processes 2024年第02期13卷 48-60页

作者： Sergio Pirain. Martín.Ariel Hadad Yan.n. An.on.a Ribas-Fern.n.ez Fidel Alejan.ro Roig Laboratorio de Den.rocron.logía e Historia Ambien.al (IAn.GLA COn.CET ) Facultad de Cien.ias Agrarias Universidad Nacional de Cuyo Laboratorio de Den.rocron.logía de Zon.s áridas (CIGEOBIO COn.CET ) Gabinete de Geología Ambiental (INGEO UNSJ) Hémera Cen.ro de Observación.de la Tierra Facultad de Ciencias Universidad Mayor

Backgroun. Recen. chan.es in.climatic tren.s are resultin. in.an.in.reased frequen.y an. in.en.ity of extreme even.s, with un.n.wn.effect on.ecosystem dyn.mics in.the n.ar future. Extreme drought episodes are recogn.zed as disturban.e factors capable of modifyin. forest dyn.mics an. tree growth. Within.this con.ext, dioecious tree species may be impacted by climatic extremes, affectin. male/female proportion. an., con.equen.ly, reproductive processes an. species persisten.e. Therefore, there is an.urgen. n.ed for species-specific assessmen.s of growth toleran.e to extreme dry spells in.dioecious tree species, to establish effective con.ervation.strategies for these particular n.tural resources. Araucaria araucan.(araucaria), an.en.an.ered dioecious Patagon.an.tree species, has recen.ly un.ergon. decay an. mortality episodes in.respon.e to in.reasin. dry climatic con.ition.. While sex-depen.en. toleran.e to extreme drought episodes has been.assessed in.the species' humid distribution.ran.e, there is still a lack of in.ormation.on.the gen.er-based resilien.e of trees growin. in.the drier en.iron.en.s of the species' *** We recon.tructed, through den.rochron.logical methods, the sex-depen.en. respon.e of 105 araucaria in.ividuals(55 female an. 50 male trees) to five region.l extreme dry spells employin. a set of differen. in.ices. Resistan.e, recovery period, an. average growth reduction.of stan.ardized tree-rin. growth were examin.d, an.lysin. the effect of biotic(sex, pre-drought stem tree growth) an. abiotic(local climatic con.ition. before, durin., an. after extreme climatic episodes) factors on.tree *** Sex in.luen.es on.y the species resistan.e to climatic disturban.e, with male in.ividuals showin. lower toleran.e to extreme drought even.s. Pre-drought radial growth rates an. local meteorological con.ition. precedin., durin., an. followin. extreme dry spells stron.ly modulated araucaria radial growth resilien.e regardless of tree s

关键词： Araucaria Climate chan.e Den.rochron.logy Extreme drought even. Resilien.e