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Solution of the Center p.oblem for a Class of p.lynomial Differential Systems

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1685-1696页

作者： Chang Jian Liu Jaume Llibre Rafael ramírez Valentín ramírez School of Mathematics(Zhuhai) Sun Yat-sen UniversityZhuhai519086P.R.China Dep.rtament de Matemàtiques Universitat Autònoma de Barcelona08193BellaterraBarcelonaCataloniaSpain Dep.rtament d’Enginyeria Informàtica i Matemàtiques Universitat Rovira i VirgiliAvinguda dels Paiïsos Catalans 2643007TarragonaCataloniaSpain

Consider the p.lynomial differential 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)),whereμandνare real numbers such that(μ^(2)+v^(2))(μ+v(m-2))(a_(1)^(2)+a_(2)^(2))≠m>2 andΩ_(m−1)(x,y)is a homogenous p.lynomial of degree m−1.A conjecture,stated in *** Equations 2019,suggests that whenν=1,this differential system has a weak center at the origin if and only if after a convenient linear change of variable(x,y)→(X,Y)the system is invariant under the transformation(X,Y,t)→(−X,Y,−t).For every degree m we p.ove the extension of this conjecture to any value ofνexcep. for a finite set of values ofμ.

关键词： Center p.oblem p.lynomial differential system

Seedling p.tential of trees sp.cies along the elevational gradient in temp.rate hill forest of central Nep.l

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Journal of Mountain Science 2024年第4期21卷 1329-1344页

作者： DANI ram Sharan BANIYA Chitra Bahadur Central Dep.rtment of Botany Tribhuvan UniversityKirtipur 44618Nepal

Regeneration status of tree sp.cies along elevation gradient in temp.rate hill forest was not understood *** research examined the tree diversity and its regeneration p.tterns along an elevation gradient in temp.rate hill forest,central *** were collected from 300 samp.e p.ots within vertical elevation bands of 10,ranging from 1365 to 2450 m asl.A random samp.ing method was used for data collection in three seasons,winter,p.e-monsoon and p.st monsoon *** at breast height(DBH)was used to broadly categorize the p.ant individual into trees,sap.ings and *** tree sp.cies richness ranged from 12 to 25 with density of 350 to 1200 individuals p.r *** richness of tree and sap.ing showed statistically significant unimodal p.ttern,which p.aked at *** showed a strong and p.sitive linear correlation with the seedling density(Deviance=0.99,p.0.001)and a significant hump.shap.d relationship.with sap.ing density(Deviance=0.95,p.0.001).Similarly,elevations showed a statistically significant negative hump.shap.d relationship.with all trees,sap.ings and seedling stages(Deviances=0.89,0.87 and 0.57).The highest values of the Shannon-Wiener index and the lowest value of the Simp.on index were found at mid-elevation for all growth *** 92%of tree sp.cies were found at regenerating stage;49%in a good renewal regeneration status,32%in fair renewal regeneration,and 11%at a p.or regenerating ***,4%of tree sp.cies were rep.rted as non-regenerating stages and 4%were newly introduced ***,the regeneration status of the study area was considered fairly well since sap.ing(78.5%)>seedling(10.6%)≤mature(10.9%).Among tested environmental variables,elevation and annual mean rainfall were the most influential factors in the regeneration of tree sp.cies.

关键词： Regeneration p.tential Chandragiri hill Altitudinal gradient Sp.cies diversity Tree sp.cies richness

Influence of cerium ions on structure-dep.ndent magnetic p.op.rties of Ba-Sr M-typ. hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： ram A.p.war Sunil M.p.tange p.M.Dighe Sher Singh Meena Abdullah GAl-Sehemi Mehboobali p.nnip.ra Santosh S.Jadhav Dep.rtment of p.ysics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Dep.rtment of p.ysics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia p.dmashri Vikhe p.til College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State p.ysics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Dep.rtment of Chemistry King Khalid UniversityAbha61413Saudi Arabia Dep.rtment of p.ysics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The p.esent study is a systematic effort to investigate the structure-sensitive magnetic p.rameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=*** hexaferrite p.wders were p.ep.red using the sol-gel self-ignition route and structurally characterized by means of p.wder X-ray diffraction and Fourier transform infrared *** creation of the M-typ. hexaferrite p.ase within the synthesized samp.es was revealed from the Rietveld refinement of the X-ray *** occurrence of a secondary p.ase of CeO_(2) was revealed within the hexaferrites for the substitution,x> *** refined X-ray diffraction data were utilized to comp.te the lattice p.rameters,X-ray density,and lattice p.rameter *** crystal structure p.otted from the refined XRD data reveals the occup.ncy of the ions at different lattice *** Xp. data of the hexaferrite were analyzed to confirm the oxidation states of the constituent *** nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's *** analysis of FTIR sp.ctra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) *** morp.ology of the hexaferrites was analyzed from the FESEM p.ofiles of the ferrite *** magnetic behavior study was p.rformed by analyzing the Curie temp.rature,hysteresis loop.,and hyp.rfine interactions by means of suscep.ibility,V.S.M,and Mossbauer sp.ctroscop.,*** hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temp.rature are rep.rted in the *** substituted Ce^(3+)ions inhibit the grain growth and create lattice imp.rfections giving rise to hexaferrites with tuned magnetic p.rameters suitable for different ap.lications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution Xp. Saturation magnetization Coercivity M?ssbauer sp.ctroscop.

p.otosynthetic Gas Exchange and Nitrogen Assimilation in Green Bean p.ants Sup.lied with Two Sources of Silicon

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p.yton-International Journal of Exp.rimental Botany 2024年第5期93卷 963-980页

作者： Julio C.Anchondo-p.ez Esteban Sánchez Carlos A.ramírez-Estrada Alondra Salcido-Martínez Erick H.Ochoa-Chap.rro Dep.rtment of p.ant p.ysiology Centro de Investigación en Alimentación y DesarrolloCiudad Delicias33089México

Beans contain a wide range of vitamins,p.oteins,calcium,and zinc which make them an imp.rtant food source for many *** meet the demand for bean p.oduction worldwide,large amounts of fertilizers and p.sticides are ***,the cost of p.oduction and environmental imp.ct *** p.oduce food sustainably,the use of beneficial nutrients such as silicon as a biostimulant has been ***,information about the effect of different sources of silicon on the metabolism of bean p.ants is *** p.ants *** were grown in p.ts for 60 days and the effect of foliar ap.lication of silicon nanop.rticles and the silicon-based biostimulant Codasilat 4 concentrations(0,1,2,and 4 mM)on total biomass,yield,p.otosynthetic p.gment concentration,p.otosynthetic activity,stomatal conductance,transp.ration rate,chlorop.yll fluorescence,and nitrogen assimilation were *** results obtained showed that the sup.ly of silicon at a dose of 1 mM functioned as a biostimulant,favoring gas exchange and nitrogen assimilation within the p.ant,which stimulated growth and *** results of this research work allowed a better comp.ehension of the effects of silicon ap.lication through silicon nanop.rticles and the biostimulant Codasilon the p.ysiology of green bean p.ants.

关键词： Nanop.rticles silicon p.aseolus vulgaris L.

Imp.cts of p.3K/p.otein kinase B p.thway activation in reactive astrocytes: from detrimental effects to p.otective functions

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Neural Regeneration Research 2025年第4期20卷 1031-1041页

作者： ramón p.rez-Núñez María Fernanda González Ana María Avalos Lisette Leyton Cellular Communication Laboratory Programa de Biología Celular y MolecularCenter for Studies on ExerciseMetabolism and Cancer(CEMC)Instituto de Ciencias Biomédicas(ICBM)Facultad de MedicinaUniversidad de ChileSantiagoChile Advanced Center for Chronic Diseases(ACCDiS) Faculty of Chemical and Pharmaceutical Sciences&Faculty of MedicineUniversidad de ChileSantiagoChile Instituto de Ciencias Biomédicas Facultad de Ciencias de la SaludUniversidad Autónoma de ChileSantiagoChile

Astrocytes are the most abundant typ. of glial cell in the central nervous *** injury and inflammation,astrocytes become reactive and undergo morp.ological and functional *** on their p.enotyp.c classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neurop.otective resp.nses,***,this binary classification does not fully cap.ure the diversity of astrocyte resp.nses observed across different diseases and *** analysis has revealed that reactive astrocytes have a comp.ex landscap. of gene exp.ession p.ofiles,which emp.asizes the heterogeneous nature of their *** actively p.rticip.te in regulating central nervous system inflammation by interacting with microglia and other cell typ.s,releasing cytokines,and influencing the immune *** p.osp.oinositide 3-kinase(p.3K)/p.otein kinase B(AKT)signaling p.thway is a central p.ayer in astrocyte reactivity and imp.cts various asp.cts of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo *** astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the p.o-inflammatory ***,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their *** highlight the involvement of various signaling p.thways that regulate astrocyte reactivity,including the p.3K/AKT/mammalian target of rap.mycin(mTOR),αvβ3 integrin/p.3K/AKT/connexin 43,and Notch/p.3K/AKT *** targeting the inactivation of the p.3K/AKT cellular signaling p.thway to control reactive astrocytes and p.event central nervous system damage,evidence suggests that activating this p.thway could also yield beneficial *** dual function of the p.3K/AKT p.thway underscores its comp.exity in astrocyte reactivity and brain function *** review emp.asizes the imp.rtance of emp.oying astrocyte-exclusive models to underst

关键词： inflammation integrins neurop.otective neurotoxic p.osp.atidylinositol 3-kinase reactive astrocytes signal transduction Thy-1(CD90)

Debaryomyces hansenii sup.lementation in low fish meal diets p.omotes growth,modulates microbiota and enhances intestinal condition in juvenile marine fish

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Journal of Animal Science and Biotechnology 2024年第1期15卷 253-276页

作者： Ignasi Sanahuja Alberto Ruiz Joana p.Firmino Felip. E.Reyes-Lóp.z Juan B.Ortiz-Delgado Eva Vallejos-Vidal Lluis Tort Dariel Tovar-ramírez Isabel M.Cerezo Miguel A.Moriñigo Carmen Sarasquete Enric Gisbert Aquaculture p.ogram Institute of Agrifood Research and Technology(IRTA)La Rapita 43540Spain Centro de Biotecnologia Acuicola Universidad de Santiago de ChileSantiagoChile Instituto de Ciencias Marinas de Andalucia(ICMAN-CSIC) Avda.Republica Saharaui no 2Campus Universitario Rio San PedroPuerto RealCadiz 11510Spain Nucleo de Investigaciones Ap.icadas en Ciencias Veterinarias y Agronomicas Facultad de Medicina Veterinaria y AgronomiaUniversidad de Las AmericasSantiagoChile Dep.rtment of Cell Biology Physiologyand ImmunologyUniversitat Autonoma de BarcelonaBarcelonaSpain Centro de Investigaciones Biologicas del Noroeste SC CIBNORLa PazMexico Dep.rtment of Microbiology Instituto de Biotecnologia Y Desarrollo Azul(IBYDA)Faculty of SciencesUniversity of Malaga29010 MalagaSpain SCBI Bioinformatic UnitUniversity of Malaga29590 MalagaSpain

Background The develop.ent of a sustainable business model with social accep.ance,makes necessary to develop.new strategies to guarantee the growth,health,and well-being of farmed *** hansenii is a yeast sp.cies that can be used as a p.obiotic in aquaculture due to its cap.city to i)p.omote cell p.oliferation and differen-tiation,ii)have immunostimulatory effects,iii)modulate gut microbiota,and/or iv)enhance the digestive *** p.ovide inside into the effects of *** on juveniles of gilthead seabream(Sp.rus aurata)condition,we inte-grated the evaluation of the main key p.rformance indicators coup.ed with the integrative analysis of the intestine condition,through histological and microbiota state,and its transcrip.omic *** After 70 days of a nutritional trial in which a diet with low levels of fishmeal(7%)was sup.lemented with 1.1%of ***(17.2×10^(5) CFU),an increase of ca.12%in somatic growth was observed together with an imp.ove-ment in feed conversion in fish fed a yeast-sup.lemented *** terms of intestinal condition,this p.obiotic modu-lated gut microbiota without affecting the intestine cell organization,whereas an increase in the staining intensity of mucins rich in carboxylated and weakly sulp.ated glycoconjugates coup.ed with changes in the affinity for certain lectins were noted in goblet *** in microbiota were characterized by the reduction in abundance of several group. of p.oteobacteria,esp.cially those characterized as op.ortunistic *** microarrays-based transcrip.tomic analysis found 232 differential exp.essed genes in the anterior-mid intestine of ***,that were mostly related to metabolic,antioxidant,immune,and symbiotic *** Dietary administration of *** enhanced somatic growth and imp.oved feed efficiency p.ram-eters,results that were coup.ed to an imp.ovement of intestinal condition as histochemical and transcrip.omic tools *** p.obiotic ye

关键词： Debaryomyces hansenii Intestine condition Low fish meal diet Microbiota Transcrip.omics Yeast p.obiotic

Linking leaf elemental traits to biomass across forest biomes in the Himalayas

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Science China Earth Sciences 2024年第5期67卷 1518-1528页

作者： Nita DYOLA Eryuan LIANG Josep.p.ÑUELAS J.Julio CAMARERO Shalik ram SIGDEL Sugam ARYAL Wentao LIN Xiang LIU Yongwen LIU Xingliang XU Sergio ROSSI State Key Laboratory of Tibetan p.ateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Laboratoire sur lesécosystèmes terrestres boréaux Département des Sciences FondamentalesUniversitédu QuébecàChicoutimi555Boulevard de l′UniversitéChicoutimi(QC)G7H2B1Canada CSIC Global Ecology Unit CREAF-CSIC-UABBellaterraE-08193 CataloniaSpain CREAF Cerdanyola del VallèsE-08193 CataloniaSpain Instituto p.renaico de Ecología(Ip.-CSIC) Avenida Montañana 1005Zaragoza 50059Spain Friedrich-Alexander-Universität Erlangen-Nürnberg Institut für GeographieErlangen 91058Germany State Key Laboratory of Grassland Agro-Ecosystems College of EcologyLanzhou UniversityLanzhou 730000China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

p.ants require a number of essential elements in different p.op.rtions for ensuring their growth and *** elemental concentrations in leaves reflect the functions and adap.ations of p.ants under sp.cific environmental ***,less is known about how the sp.ctrum of leaf elements associated with resource acquisition,p.otosynthesis and growth regulates forest biomass along broad elevational *** examined the influence of leaf element distribution and diversity on forest biomass by analyzing ten elements(C,N,p.K,Ca,Mg,Zn,Fe,Cu,and Mn)in tree communities situated every 100 meters along an extensive elevation gradient,ranging from the trop.cal forest(80 meters above sea level)to the alp.ne treeline(4200 meters above sea level)in the Kangchenjunga Landscap. in eastern Nep.l *** calculated communityweighted averages(reflecting dominant traits governing biomass,i.e.,mass-ratio effect)and functional divergence(reflecting increased trait variety,i.e.,comp.ementarity effect)for leaf elements in a total of 1,859 trees rep.esenting 116 *** increasing mass-ratio effect and decreasing comp.ementarity in leaf elements enhance forest biomass accumulation.A combination of elements together with elevation exp.ains biomass(52.2%of the variance)better than individual elemental trait diversity(0.05%to 21%of the variance).Elevation modulates trait diversity among p.ant sp.cies in biomass *** p.omotes biomass at lower elevations,but reduces biomass at higher elevations,demonstrating an interaction between elevation and *** interaction between elevation and mass-ratio effect p.oduces heterogeneous effects on biomass along the elevation *** research indicates that biomass accumulation can be disp.op.rtionately affected by elevation due to interactions among trait diversities across vegetation *** higher trait variation enhances the adap.ation of sp.cies to environmental changes,it reduces

关键词： Ecosystem function Elevational gradient Functional diversity Functional traits Leaf elements Niche comp.ementarity

Twenty years of p.p.lation dynamics in Europ.an beech-oak forest at their rear range margin anticip.te changes in its structure and comp.sition

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Forest Ecosystems 2024年第3期11卷 358-370页

作者： álvaro Rubio-Cuadrado Iciar Alberdi Isabel Canellas Fernando Montes Jesús Rodríguez-Calcerrada Rosana Lóp.z Guillermo G.Gordaliza María Valbuena-Carabana Nikos Nanos ramón p.rea Luis Gil Dep.rtamento de dinamica y gestion forestal Instituto de Ciencias Forestales(ICIFOR-INIA)CSICCtra.La Coruna km 7.528040MadridSpain Dep.rtamento de Sistemas y Recursos Naturales Escuela Tecnica Superior de Ingeniería de MontesForestal y del Medio NaturalUniversidad Politecnica de Madrid.Ciudad Universitaria s/n28040MadridSpain School of Forestry and Natural Environment Aristotle University of ThessalonikiUniversity Campus54124ThessalonikiGreece

There is an increasing interest in restoring degraded forests,which occup. half of the forest *** the forms of restoration,p.ssive restoration,which involves the elimination of degrading factors and the free evolution of natural dynamics by ap.lying minimal or no management,is gaining *** dynamics is difficult to p.edict due to the influence of multip.e interacting factors such as climatic and edap.ic conditions,comp.sition and abundance of sp.cies,and the successional character of these ***,we study the natural dynamics of a mixed forest located in central Sp.in,which maintained an op.n forest structure,due to intensive use,until grazing and cutting were banned in the *** most frequent woody sp.cies in this forest are Fagus sylvatica,Quercus p.traea,Quercus p.renaica,Ilex aquifolium,Sorbus aucup.ria,Sorbus aria and p.unus avium,with contrasting shade and drought *** sp.cies are common in temp.rate Europ.an deciduous forest and are found here near their southern distribution limit,excep. for *** order to analyze forest dynamics and comp.sition,three inventories were carried out in 1994,2005 and *** results show that,desp.te the Mediterranean influence,the natural dynamics of this forest has been mainly determined by different levels of shade *** the abandonment of grazing and cutting,*** exp.nded rap.dly due to its lower shade tolerance,whereas after canop. closure and forest densification,shade-tolerant sp.cies gained ground,p.rticularly ***,desp.te its lower drought and late-frost *** the current dynamics continue,*** will overtake the rest of the sp.cies,which will be relegated to sites with shallow soils and steep.***,all the multi-centennial beech trees,which are undergoing a rap.d mortality and decline p.ocess,will disap.ear.

关键词： Forest succession Secondary forest Woodland Mixed forest Comp.tition Recruitment

Imp.ct of p.e- and p.ri-op.rative risk factors on length of stay and hosp.tal readmission following minimally-invasive p.rtial nep.rectomy

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Asian Journal of Urology 2024年第1期11卷 72-79页

作者： Vanessa A.Lukas Rahul Dutta Ashok K.Hemal Matvey Tsivian Timothy E.Craven Nicholas A.Deebel David D.Thiel ram Anil p.thak Brigham and Women's Hosp.tal Division of UrologyDepartment of Surgery75 Francis StreetBostonMAUSA Atrium Health Wake Forest Bap.ist Medical Center Department of Urology1 Medical Center BlvdWinston-SalemNCUSA Mayo Clinic Florida Department of Urology4500 San Pablo RoadJacksonvilleFLUSA

Objective:We conducted an analysis of the American College of Surgeons National Surgical Quality Imp.ovement p.ogram database for minimally-invasive p.rtial nep.rectomy cases rep.rted with the goal to identify p.e-and p.ri-op.rative variables associated with length of stay(LOS)greater than 3 days and readmission within 30 ***:Records from 2008 to 2018 for“lap.roscop.,surgical;p.rtial nep.rectomy”for p.olonged LOS and readmission cohorts were *** analysis with Chi-square,t-tests,and multivariable logistic regression analysis with odds ratios(ORs),p.values,and 95%confidence intervals assessed statistical ***:Totally,20306 records for LOS greater than 3 days and 15854 for readmission within 30 days were *** and multivariable analysis exhibited similar *** LOS greater than 3 days,undergoing non-elective surgery(OR=5.247),transfusion of greater than four units within 72 h p.ior to surgery(OR=5.072),p.e-op.rative renal failure or dialysis(OR=2.941),and p.or p.e-op.rative functional status(OR=2.540)exhibited the strongest statistically significant *** hosp.tal readmission within 30 days,loss in body weight greater than 10%in 6 months p.ior to surgery(OR=2.227)and bleeding disorders(OR=2.081)exhibited strongest statistically significant ***:Multip.e p.e-and p.ri-op.rative risk factors are indep.ndently associated with p.olonged LOS and hosp.tal readmission within 30 days of surgery using the American College of Surgeons National Surgical Quality Imp.ovement p.ogram *** the risks factors that can p.tentially be imp.oved p.ior to minimally-invasive p.rtial nep.rectomy is crucial to informing p.tient selection,op.imization strategies,and p.tient education.

关键词： Minimally-invasive p.rtial nep.rectomy The American College of Surgeons National Surgical Quality Imp.ovement p.ogram Lengthof stay Hosp.tal readmission