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Solution of the Center Problem for a Class of Polynomial 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 Departament de Matemàtiques Universitat Autònoma de Barcelona08193BellaterraBarcelonaCataloniaSpain Departament d’Enginyeria Informàtica i Matemàtiques Universitat Rovira i VirgiliAvinguda dels Paiïsos Catalans 2643007TarragonaCataloniaSpain

Consider the polynomial 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 polynomial 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 prove the extension of this conjecture to any value ofνexcept for a finite set of values ofμ.

关键词： Center problem polynomial differential system

Understanding the Link:Emotional Attention in Italian Families and Children’s Social Development

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International Journal of Mental Health Promotion 2024年第9期26卷 709-718页

作者： Catalda Corvasce Juan Pedro Martínez-ramón Francisco Manuel Morales-Rodríguez Lidia Pellicer-García Inmaculada Méndez Cecilia Ruiz-esteban Liceo Statale“Carlo Cafiero” Barletta(BT)76121Italy Department of Developmental Psychology and Education University of MurciaMurcia30100Spain Department of Developmental Psychology and Education University of GranadaCampus of La CartujaGranadaCP 18071Spain Department of Spanish Language and General Linguistics University of MurciaCampus of La MercedMurciaCP 30001Spain

Background:Emotional attention refers to the capacity to recognize and properly respond to one’s and others’emotional *** another note,family is a primary source of socialization that influences the development of various social *** another line,adolescence is a complex stage that has been associated with emotional difficulties that could be related to competences such as prosociability and *** is inferred that through the family context and the attention that is processed,a series of competencies are transmitted to the youngsters,but this relationship is still *** this reason,the study’s purpose was to examine the relationship between the emotional attention of mothers and fathers and the social and prosocial competencies of their ***:To accomplish this,a cross-sectional study and ex post facto design were *** Trait-Meta Mood Scale(TMMS-24)-to assess emotional attention-,the Strengths and Difficulties Questionnaire(SDQ)-to determine the prosociality dimension-,and the Test on Passing Developmental Tasks in Adolescence(TCS-A)-to measure social inclusionwere *** participants were n=228 families composed of n=114 mothers/fathers(67.5%females)and n=114 daughters/sons(38.5%females)selected through non-probabilistic sampling using a convenience sample in the Bari region of Italy.A descriptive and inferential analysis-Student’s test and Pearson’s correlation-was performed with the statistic package SPSS version 28(significance level pndings showed that the families possessed an adequate background in emotional attention and that their daughters and sons were also generally well-adjusted in social inclusion and *** also found certain signs that the prosocial competence of the children could be related to the behavior of their mothers and ***:In conclusion,social inclusion is related to prosocial behavior,and maybe primarily cultivated within families where paren

关键词： Educational style coping strategies stress social inclusion emotional attention prosociality

A Generalized Array Factor for Time-Modulated Hexagonal Based Antenna Array Geometry With novel Trapezoidal Switching

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1967-1972页

作者： Gopi ram Department of Electronics and Communication Engineering National Institute of TechnologyWarangal 506004India

The concept of the time-modulated array has been emerging as an alternative to the complex phase shifters,which lowers the cost of the array feeding network due to the utilization of radio frequency(RF)*** various forms of hexagonal antenna array geometries can be used for applications like surveillance tracking in phased array radar and wireless communication *** work proposes the generalized array factor(AF)for the hexagonal antenna array geometry based on time *** time modulation in generalized hexagonal geometry can maintain the fixed static amplitude excitation,giving more flexibility over ***,a novel trapezoidal switching function is also proposed and applied to the generalized array factor to enable future researchers to use this array factor in the field of advancement to observe how switching schemes like trapezoidal and rectangular affect the array pattern's side lobe level(SLL).The generalized equation can be utilized for the analysis and synthesis of radiation characteristics of the time-modulated hexagonal array(TMHA),time-modulated concentric hexagonal array(TMCHA),time-modulated hexagonal cylindrical array(TMHCA),and time-modulated hexagonal concentric cylindrical array(TMHCCA).The numerical result illustrates the generation of AF of time-modulated hexagonal structures and also shows that the trapezoidal switching sequence outperforms the rectangular switch using the cat swarm optimization(CSO)approach.

关键词： Hexagonal array geometry radiation pattern time-modulation trapezoidal pulse

A Probabilistic Trust Model and Control Algorithm to Protect 6G networks against Malicious Data Injection Attacks in Edge Computing Environments

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 631-654页

作者： Borja Bordel Sánchez ramón Alcarria Tomás Robles Department of Computer Systems Universidad Politécnica de MadridMadrid28031Spain Department of Geospatial Engineering Universidad Politécnica de MadridMadrid28031Spain

Future 6G communications are envisioned to enable a large catalogue of pioneering *** will range from networked Cyber-Physical Systems to edge computing devices,establishing real-time feedback control loops critical for managing Industry 5.0 deployments,digital agriculture systems,and essential *** provision of extensive machine-type communications through 6G will render many of these innovative systems autonomous and *** full automation will enhance industrial efficiency significantly,it concurrently introduces new cyber risks and *** particular,unattended systems are highly susceptible to trust issues:malicious nodes and false information can be easily introduced into control ***,Denialof-Service attacks can be executed by inundating the network with valueless *** anomaly detection schemes require the entire transformation of the control software to integrate new steps and can only mitigate anomalies that conform to predefined mathematical *** based on an exhaustive data collection to detect anomalies are precise but extremely *** models,with their limited understanding of mobile networks,can achieve precision rates no higher than 75%.Therefore,more general and transversal protection mechanisms are needed to detect malicious behaviors *** paper introduces a probabilistic trust model and control algorithm designed to address this *** model determines the probability of any node to be *** channels are pruned for those nodes whose probability is below a given *** trust control algorithmcomprises three primary phases,which feed themodel with three different probabilities,which are weighted and ***,anomalous nodes are identified using Gaussian mixture models and clustering ***,traffic patterns are studied using digital Bessel functions and the functional scalar ***,the in

关键词： 6G networks noise injection attacks Gaussian mixture model Bessel function traffic filter Volterra filter

Photosynthetic Gas Exchange and nitrogen Assimilation in Green Bean Plants Supplied with Two Sources of Silicon

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 963-980页

作者： Julio C.Anchondo-Páez esteban Sánchez Carlos A.ramírez-Estrada Alondra Salcido-Martínez Erick H.Ochoa-Chaparro Department of Plant Physiology Centro de Investigación en Alimentación y DesarrolloCiudad Delicias33089México

Beans contain a wide range of vitamins,proteins,calcium,and zinc which make them an important food source for many *** meet the demand for bean production worldwide,large amounts of fertilizers and pesticides are ***,the cost of production and environmental impact *** produce 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 plants is *** plants *** were grown in pots for 60 days and the effect of foliar application of silicon nanoparticles and the silicon-based biostimulant Codasilat 4 concentrations(0,1,2,and 4 mM)on total biomass,yield,photosynthetic pigment concentration,photosynthetic activity,stomatal conductance,transpiration rate,chlorophyll fluorescence,and nitrogen assimilation were *** results obtained showed that the supply of silicon at a dose of 1 mM functioned as a biostimulant,favoring gas exchange and nitrogen assimilation within the plant,which stimulated growth and *** results of this research work allowed a better comprehension of the effects of silicon application through silicon nanoparticles and the biostimulant Codasilon the physiology of green bean plants.

关键词： nanoparticles silicon Phaseolus vulgaris L.

Assessment of compressive strength of jet grouting by machine learning

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 102-111页

作者： esteban Diaz Edgar Leonardo Salamanca-Medina Roberto Tomas Departamento de Ingeniería Civil Escuela Politécnica SuperiorUniversidad de AlicanteP.O.Box 99E-03080AlicanteSpain

Jet grouting is one of the most popular soil improvement techniques,but its design usually involves great uncertainties that can lead to economic cost overruns in construction *** high dispersion in the properties of the improved material leads to designers assuming a conservative,arbitrary and unjustified strength,which is even sometimes subjected to the results of the test *** present paper presents an approach for prediction of the uniaxial compressive strength(UCS)of jet grouting columns based on the analysis of several machine learning algorithms on a database of 854 results mainly collected from different research *** selected machine learning model(extremely randomized trees)relates the soil type and various parameters of the technique to the value of the compressive *** the complex mechanism that surrounds the jet grouting process,evidenced by the high dispersion and low correlation of the variables studied,the trained model allows to optimally predict the values of compressive strength with a significant improvement with respect to the existing ***,this work proposes for the first time a reliable and easily applicable approach for estimation of the compressive strength of jet grouting columns.

关键词： Jet grouting Ground improvement Compressive strength Machine learning

Wood anatomical acclimation in the endemic genus Polylepis in Peruvian Andean forests

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Journal of Mountain Science 2024年第9期21卷 2986-3000页

作者： Anthony GUERRA Fressia n.AMES-MARTÍnEZ Ernesto C.RODRÍGUEZ-ramÍREZ Postgraduate Programme in Agronomy/Plant Physiology Department of Biology-Institute of natural Sciences Federal University of LavrasLavras 37203-202Minas Gerais 30000-31999Brazil Laboratory of Biotechnology and Molecular Biology Continental UniversitySan Antonio UrbanizationHuancayo 12000Peru Ecology and Biodiversity Research Programme ANDINUS AssociationMiguel Grau Street 370Huancayo 12000Peru Dendrochronology Laboratory Continental UniversitySan Carlos Avenue 1980Huancayo 12000Peru

Polylepis(Queñua)is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism,which may be particularly threatened by climate *** anatomical traits are essential for understanding how plants adjust their ecophysiological requirements and maximize their resilience,resistance,and recovery to extreme *** the effects of extreme climatic conditions in high altitude ecosystems have been studied extensively,our knowledge is relatively limited to quantitative differences in the main xylem *** address this gap,we assessed the acclimation of wood anatomical traits in six Peruvian Andean Polylepis species with different water availability(semi-dry with high moisture and semiarid with dry winters).We selected hydraulic diameter,vessel density,vessel grouping index,solitary vessel index,vulnerability index,mesomorphy index,vessel element length,fiber length,fiber wall thickness,fiber lumen diameter,and total fiber diameter that can provide relevant eco-wood anatomical acclimation to hydric *** performed multivariate analysis to determine the leading dimensions of covariation among Polylepis species and climatic *** wood anatomical traits(vessel grouping index,vulnerability index,and fiber wall thickness)were dissimilar between xeric-and mesic-Polyelpis *** study demonstrates that wood anatomical traits in Peruvian Andean Polylepis species provides high-resolution and long-term eco-wood anatomical signals on how climate oscillations drive the acclimation processes of fiber and vessel *** findings underscore the significance of xylem hydraulic adjustment to various hydrological environments in Andean puna *** evaluating the effects of drought on wood anatomical characteristics and ecological function,we demonstrate the capacity of tree species to adapt and endure climate-related changes,thereby emphasizing their resilience and ada

关键词： Carlquist indices Climatic resilience Vessel traits Fiber Functional trait Hydric stress

Seedling potential of trees species along the elevational gradient in temperate hill forest of central nepal

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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 Department of Botany Tribhuvan UniversityKirtipur 44618Nepal

Regeneration status of tree species along elevation gradient in temperate hill forest was not understood *** research examined the tree diversity and its regeneration patterns along an elevation gradient in temperate hill forest,central *** were collected from 300 sample plots within vertical elevation bands of 10,ranging from 1365 to 2450 m asl.A random sampling method was used for data collection in three seasons,winter,pre-monsoon and post monsoon *** at breast height(DBH)was used to broadly categorize the plant individual into trees,saplings and *** tree species richness ranged from 12 to 25 with density of 350 to 1200 individuals per *** richness of tree and sapling showed statistically significant unimodal pattern,which peaked at *** showed a strong and positive linear correlation with the seedling density(Deviance=0.99,pnd a significant hump-shaped relationship with sapling density(Deviance=0.95,pns showed a statistically significant negative hump-shaped relationship with all trees,saplings 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 Simpson index were found at mid-elevation for all growth *** 92%of tree species were found at regenerating stage;49%in a good renewal regeneration status,32%in fair renewal regeneration,and 11%at a poor regenerating ***,4%of tree species were reported as non-regenerating stages and 4%were newly introduced ***,the regeneration status of the study area was considered fairly well since sapling(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 species.

关键词： Regeneration potential Chandragiri hill Altitudinal gradient Species diversity Tree species richness

Development of novel 5-FU modified siRnA against BCL-2 with enhanced efficacy and vehicle-free cellular uptake

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Genes & Diseases 2024年第1期11卷 23-25页

作者： Andrew Fesler Ga-ram Hwang Jingfang Ju Department of Pathology Renaissance School of MedicineStony Brook UniversityStony BrookNY 11794USA The northport Veteran's Administration Medical Center NorthportNY 11768USA Curamir Therapeutics Inc. WoburnMA 01801USA

One of the major obstacles for nucleic acid-based medicine is cellular uptake due to the concern of efficiencyand potential toxicity of the *** this work,we developed a novel approach to eliminate the need for a vehicle to allow for the cellular uptake of siRnA-based therapy with a unique modification strategy that also further enhances therapeutic *** discovery may be of great importance for the development of siRnA-based therapeutics as cellular uptake remains a critical *** this study,we have tested the potential of this modification strategy for siRnA using a siRnA that targets B-cell lymphoma-2(BCL-2).

关键词： eliminate uptake modified