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Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

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Applied Mathematics and Mechanics(english edition) 2024年第4期45卷 633-648页

作者： e.GHAVANLOO S.eL-BORGI School of Mechanical engineering Shiraz UniversityShiraz 71963-16548Iran Mechanical engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPM).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(MMS)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPM for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPM) method of multiple scales(MMS) dispersion phase velocity

Annual variation of adult survival of a south-temperate House Wren population in Argentina

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Avian Research 2024年第2期15卷 229-237页

作者： Gustavo J.Fernandez Mariana e.Carro Paulo e.Llambías Grupo de Investigacion en ecofisiología de Fauna Silvestre INIBIOMA-CONICETAsentamiento Universitario San Martín de los Andes(AUSMA)Universidad Nacional Del ComahuePasaje de la Paz 235(8370)San Martín de los AndesNeuquenArgentina Grupo de Investigacion de Biología de Aves IADIZA CCT-MendozaUniversidad Nacional de CuyoAvenida RuizLeal s/n Parque General San Martin5500MendozaArgentina

Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population *** numerous studies on this subject in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the ***,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival *** found that the probability of adult survival decreased as the abundance of breeding adults *** density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival.

关键词： Annual variation CJS Density-dependence Survival Troglodytes aedon bonariae

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 states. On another note, family is a primary source of socialization that influences the development of various social skills. In another line, adolescence is a complex stage that has been associated with emotional difficulties that could be related to competences such as prosociability and inclusion. It 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 unclear. For 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 children. Methods To accomplish this, a cross-sectional study and ex post facto design were conducted. The 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 inclusion-were administered. The 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 p esults The findings 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 prosociality. It also found certain signs that the prosocial competence of the children could be related to the behavior of their mothers and fathers. Conclusion In conclusion, social inclusion is related to prosocial behavior, and maybe primari

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

Converting TRex-RGB green-channel data to 557.7 nm auroral intensity:Methodology and initial results

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earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.M.Gillies e.Spanswick e.F.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region explorer(TRex)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TRex-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TRex mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TRex spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TRex-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TRex-RGB data *** methodology established in this study will also be applicable to the upcoming SMILe ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TRex RGB green-line aurora auroral transport model

effect of rhenium on the microstructure and mechanical behavior of Fe–2.25Cr–1.6W–0.25V-0.1C bainitic steels

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Journal of Materials Science & Technology 2017年第12期33卷 1487-1493页

作者： José Antonio jiménez Manuel Carsí Oscar Antonio Ruano Department of Physical Metallurgy Centro Nacional de lnvestigaciones MetalurgicasC.S.I.CAvda.Gregorio del Amo 828040 MadridSpain

A new ferritic creep resistant steel has been developed by eliminating Nb and adding 1.5 mass % Re to a ferritic steel grade T/P23 with the aim of enhancing its mechanical properties at high *** ingots of both steels, new grade and ASTM T/P 23, were hot rolled at 900℃ and then submitted to a thermal treatment consisting of solubilization at 1050℃ and tempering at 700℃. Tempered bainitic microstructures obtained contain second phases reinforcing carbide particles, mainly M_6C and M_（23）C_6 at the boundaries of both, prior austenite grains and bainitic ferrite laths, as well as MC within the grains. Mechanical properties at temperatures ranging from 540 to 600℃ were studied by strain-ratechange tests in compression at strain rates between 10^（-7） and 10^（-4）s^（-1）. These tests showed high stress exponents（n ≥ 20） and activation energies（Q ≈ 400 k J/mol） for both alloys, which were associated with a dislocation movement mechanism with a strong interaction between dislocations and precipitates. On the other hand, a creep exponent of 5 was derived for the stress dependence of minimum creep rate from conventional-type creep tests at 600℃. Although this stress exponent is usually related to a dislocation climb controlled creep mechanism, remarkable microstructural degradation observed with increasing creep time makes difficult to elucidate the true deformation mechanism controlling creep.

关键词： Creep resistant steel T/P23 Thermal treatment Tempered bainite High temperature mechanical properties Creep

eventual Leader election with Weak Assumptions on Initial Knowledge,Communication Reliability,and Synchrony

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Journal of Computer Science & Technology 2010年第6期25卷 1267-1281页

作者： Antonio Fernndez Anta ernesto jimnez Michel Raynal Institute IMDeA Networks Avenida del Mar Mediterraneo eUI Universidad Politcnica de Madrid IRISA Universit de Rennes

This paper considers the eventual leader election problem in asynchronous message-passing systems where an arbitrary number t of processes can crash（t〈n,where n is the total number of processes）.It considers weak assumptions both on the initial knowledge of the processes and on the network *** precisely,initially,a process knows only its identity and the fact that the process identities are different and totally ordered（it knows neither n nor t）.Two eventual leader election protocols and a lower bound are *** first protocol assumes that a process also knows a lower bound α on the number of processes that do not *** protocol requires the following behavioral properties from the underlying network：the graph made up of the correct processes and fair lossy links is strongly connected,and there is a correct process connected to（n〈f）-α other correct processes（where f is the actual number of crashes in the considered run） through eventually timely paths（paths made up of correct processes and eventually timely links）.This protocol is not communication-efficient in the sense that each correct process has to send messages *** second protocol is communication-efficient：after some time,only the final common leader has to send messages *** protocol does not require the processes to know α,but requires stronger properties from the underlying network：each pair of correct processes has to be connected by fair lossy links（one in each direction）,and there is a correct process whose n〈f-1 output links to the rest of correct processes have to be eventually timely.A matching lower bound result shows that any eventual leader election protocol must have runs with this number of eventually timely links,even if all processes know all the processes *** addition to being communication-efficient,the second protocol has another noteworthy efficiency property,namely,be the run finite or infinite,all the local variables and message fields have

关键词： eventually timely and fair lossy links eventual leader election failure detector omega leader oracle process initial knowledge

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二硫化碳作为谷物熏蒸剂的新观点

粮油食品科技 2024年第3期32卷 1-15页

作者： jim DeSMARCHeLIeR Yu XIAO Li GU Yong-lin ReN 李燕羽(译) 默多克大学环境和生命科学学院澳大利亚珀斯WA 6150 国家粮食和物资储备局科学研究院粮食储运研究所

虽然二硫化碳(CS_(2))是一种古老的熏蒸剂,但澳大利亚新数据以及中国和埃及已发表的研究数据使它可被人们重新关注。这些数据包括谷物质量、自然释放和加工食品中的残留,但目前并不广为人知。埃及研究数据显示,即使在400 mg/m^(3)高剂量... 详细信息

虽然二硫化碳(CS_(2))是一种古老的熏蒸剂,但澳大利亚新数据以及中国和埃及已发表的研究数据使它可被人们重新关注。这些数据包括谷物质量、自然释放和加工食品中的残留,但目前并不广为人知。埃及研究数据显示,即使在400 mg/m^(3)高剂量下,二硫化碳对水稻的发芽率和幼芽长度都没有影响。中国研究数据显示,200 mg/m^(3)高剂量对大麦、小麦、玉米、高粱、棉花、胡萝卜等大多数种子发芽率没有影响。本研究中150 mg/L剂量对澳大利亚小麦、大麦以及鹰嘴豆发芽率和幼芽长度的影响数据也证明了这一点。澳大利亚储藏谷物研究实验室(SGRL)的商业规模实验数据表明,二硫化碳在1000~1500 mg·h·L^(-1)的CT值(浓度×时间)范围内可杀死所有受试昆虫,并且对小麦最终产品质量没有影响。二硫化碳在谷物上的吸附力低于甲基溴,且主要是物理吸附。它会在谷物上有残留物,但这些残留物在储存和加工的过程中会被大量降解,而剩余的二硫化二苯醚残留物会在小麦制粉前的清理和润麦过程中减少。在制粉和烘烤的过程中,二硫化碳的残留量会逐渐减少。例如,将含有27 g/m^(3)二硫化碳的小麦在仓内密封放置6 d,然后通风24 h,清理会使制粉前的残留量从6.7 mg/kg降至4.6 mg/kg,润麦会使残留量从4.6 mg/kg降至2.2 mg/kg。在制粉的过程中,残留量会进一步减少,而在面条(甚至在烹饪前)、意大利面以及面包的制作过程中,残留量还会进一步减少。当前检测分析方法无法检测加工产品中的残留量(定量限值<0.005 mg/kg),且其残留水平与同一来源未经二硫化碳熏蒸的小麦制品相同。

关键词：熏蒸剂二硫化碳吸附性发芽率残留

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Advances in spinal cord injury:insights from non-human primates

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Neural Regeneration Research 2024年第11期19卷 2354-2364页

作者： Gaetan Poulen Florence e.Perrin University of Montpellier INSERMEPHEMontpellierFrance Department of Neurosurgery Gui de Chauliac HospitalMontpellier University Medical CenterMontpellierFrance Institut Universitaire de France(IUF) ParisFrance

Spinal cord injury results in significant sensorimotor deficits,currently,there is no curative treatment for the symptoms induced by spinal cord *** and pre-clinical research on spinal cord injury relies on the development and characterization of appropriate animal *** models should replicate the symptoms observed in human,allowing for the exploration of functional deficits and investigation into various aspects of physiopathology of spinal cord ***-human primates,due to their close phylogenetic association with humans,share more neuroanatomical,genetic,and physiological similarities with humans than ***,the responses to spinal cord injury in nonhuman primates most likely resemble the responses to traumatism in *** this review,we will discuss nonhuman primate models of spinal cord injury,focusing on in vivo assessments,including behavioral tests,magnetic resonance imaging,and electrical activity recordings,as well as ex vivo histological ***,we will present therapeutic strategies developed in non-human primates and discuss the unique specificities of non-human primate models of spinal cord injury.

关键词： behavior cellular analysis non-human primates spinal cord injury tissue analysis

Natural sediment at a dam and its inorganic materials as adsorbents of praseodymium(Pr(Ⅲ))

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International Journal of Sediment Research 2023年第4期38卷 566-575页

作者： Melania jiménez-Reyes Jaime jiménez-Becerril Marcos Solache-Ríos Perla Tatiana Almazán-Sánchez Departamento de Química Instituto Nacional de Investigaciones Nucleares Carretera México-Toluca S/N CONACy T-Instituto Nacional de Investigaciones Nucleares

The sediment deposited behind a dam(DS) and its inorganic materials(IM-DS) were characterized and used for the removal of praseodymium(Pr) from aqueous solutions. Quartz, albite, and kaolinite were found in the sediment by X-ray diffraction. Kinetic data fit well to a pseudo second-order model, the equilibrium time for DS and IM-DS was 2 h and 3 min, respectively, and the adsorption capacity was higher for Pr/DS(qe= 4.91 mg/g) than for Pr/IM-DS(qe= 3.01 mg/g) in these conditions. Pr/DS and Pr/IM-DS data isotherms were in agreement with the Langmuir-Freundlich model and the maximum adsorption capacities were 4.95 and 4.01 mg/g, respectively. Both processes are exothermic(enthalpy change, ΔH0=-22.8 and-21.8 k J/mol for DS and IM-DS, respectively), the increase of the randomness is small, and the feasibility and spontaneity are low. Praseodymium was desorbed by ethylenediaminetetraacetic acid disodium(eDTA-Na2), sodium chloride, nitric, citric, and humic acids solutions, and one hundred percent of praseodymium was desorbed by the eDTA-Na2solution. The Pr2(eDTA)3(praseodymium ethylenediaminetetraacetate) complex was completely desorbed from both materials(DS and IM-DS). Distribution coefficients(KD) depend upon praseodymium concentration,temperature, p H, and the kind of adsorbent. Chemical reactions of praseodymium with kaolinite and iron minerals could explain the adsorption.

关键词： Praseodymium Sediment Adsorption process parameters Desorption