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Journal of Modern Transportation 2015年第3期23卷 189-201页

作者： Julia Irene Real Clara Zamorano josé luis velarte Antonio Enrique Blanco University Institute for Multidisciplinary Mathematics Polytechnic University of Valencia Foundation for the Research and Engineering in Railways

Imperfections in the wheel-rail contact are one of the main sources of generation of railway vibrations. Consequently, it is essential to take expensive corrective maintenance measures, the results of which may be unknown. In order to assess the effectiveness of these measures, this paper develops a vehicle-track interaction model in the time domain of a curved track with presence of rail corrugation on the inner rail. To characterize the behavior of the track, a numerical finite element model is developed using ANSYS software, while the behavior of the vehicle is characterized by a unidirectional model of two masses developed with VAMPIRE PRO software. The overloads obtained with the dynamic model are applied to the numerical model and then, the vibrational response of the track is obtained. Results are validated with real data and used to assess the effectiveness of rail grinding in the reduction of wheel-rail forces and the vibration generation phenomenon.

关键词： Corrugation · Dynamic overloads · Finiteelement method · Vibrations

世界水土保持学会副主席,水土保持专家joséluis Rubio先生论森林火灾后土壤的保护与修复:生物工程的作用

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水土保持通报 2019年第1期39卷 310-316页

作者： josé luis Rubio 西班牙巴伦西亚大学沙漠化研究中心

[目的]讨论火灾地区土壤保护的基本方法,旨在从生物多样性和美学价值方面,阐述新兴生物工程领域在修复与固结土壤,保护土壤免遭不同类型侵蚀,维持景观质量等方面中的应用。[方法]通过综述和评价现行生物工程技术在西班牙森林火灾后土壤... 详细信息

[目的]讨论火灾地区土壤保护的基本方法,旨在从生物多样性和美学价值方面,阐述新兴生物工程领域在修复与固结土壤,保护土壤免遭不同类型侵蚀,维持景观质量等方面中的应用。[方法]通过综述和评价现行生物工程技术在西班牙森林火灾后土壤保持和土壤修复中的应用,阐述了有关基本原理,并介绍了一些生物工程技术在受火灾影响的不同地区的成功应用案例。[结果]生物工程技术用于森林火灾后土壤保护和修复的重要基础知识部分仍基于土壤保持的一些传统原理,尤其在与具体干预的立地和简单技术应用的生态一致性方面。同时也不应低估新近土木工程的作用。这些土木工程技术(包括金属笼的使用)为生物要素(主要是植物物质)发挥更大作用提供了条件,而这些生物要素是在特定干预区气候或生物物理条件下发挥固结土壤作用的重要因素。与活体材料一起使用的还有各种生物物质,例如植物残留物,砍下的灌木,木质化元素,以及多种土工织物。这些技术可以归结分为4组主要形式:(1)土壤保护技术,(2)地面稳定技术,(3)重建技术组合,(4)其他稳定技术。[结论]用于土壤保护的生物工程技术提供了一种更为环保和具有长期有效性的方法。它同时具有耗资低,适应性强和提供多功能景观效益等优势。然而,生物技术也存在一些缺陷,例如人力资源需求,缺乏有关知识和合适的植物物质,特别是在一些干旱气候地区。尽管如此,生物工程方法在满足森林火灾影响后土壤保护的紧急干预措施这类新需求过程中表现出其正在崛起,有应用前途和快速发展的态势。

关键词：森林火灾生物工程土壤保持与修复环境一致性

Glyphosate Dissipation in Different Soils Under No-Till and Conventional Tillage

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Pedosphere 2019年第6期29卷 773-783页

作者： Elena OKADA joséluis COSTA Francisco BEDMAR Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Balcarce 7620(Argentina Estación Experimental Agropecuaria Balcarce Instituto Nacional de Tecnología Agropecuaria(INTA)Balcarce 7620(Argentina Facultad de Ciencias Agrarias Universidad Nacional de Mar del PlataBalcarce 7620(Argentina

Glyphosate is the most used herbicide in Argentina, accounting for 62% of the commercialized pesticides on the market. It is used as a weed controller in no-till systems, and it is also applied to various genetically modified crops ( e.g., soybean, corn, and cotton). Although it has a high solubility in water, it tends to adsorb and accumulate in agricultural soils. The main objectives of this work were to compare the dissipation of glyphosate and the accumulation of its metabolite aminomethylphosphonic acid (AMPA) over time in three soils from agricultural areas of Argentina under long-term management with no-till (NT) and conventional tillage (CT) practices. There were no differences in dissipation between NT and CT, indicating that the glyphosate-degrading microflora was not modified by the different tillage managements. Moreover, tillage practices did not alter the general soil properties;therefore, glyphosate bioavailability was not affected by NT or CT practice. Forty percent of the applied glyphosate was degraded within the first three days in all soils, indicating a fast initial dissipation rate. However, the dissipation rate considerably decreased over time, and the degradation kinetics followed a bi-exponential (or two-compartment) kinetic model. No differences were found between tillage practices. Dissipation was not related to the microbial activity measured as soil respiration. The fast decrease in the concentration of glyphosate at the beginning of the dissipation study was not reflected in an increase in the concentration of AMPA. The estimated half-lives for glyphosate ranged between 9 and 38 d. However, glyphosate bioavailability decreases over time, as it is strongly adsorbed to the soil matrix. This increases its residence time, which may lead to its accumulation in agricultural soils.

关键词： Aminomethylphosphonic acid Bioavailability Biodegradation Herbicide Metabolite Pesticide Two-compartment kinetic model

Sintering study of Ti6Al4V powders with different particle sizes and their mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1389-1401页

作者： joséluis Cabezas-Villa joséLemus-Ruiz Didier Bouvard Omar Jiménez Héctor Javier Vergara-Hernández luis Olmos University Michoacana of San Nicolás of Hidalgo IIMMMorelia 58060México University Grenoble Alpes CNRSSIMaPGrenoble 38000France University of Guadalajara Departamento de Ingeniería de ProyectosZapopan 45100México National Technological Institute of Mexico I.T.MoreliaMorelia 58120México University Michoacana of San Nicolás of Hidalgo INICITMorelia 58060México

Ti6Al4V powders with three different particle size distributions(0–20, 20–45, and 45–75 μm) were used to evaluate the effect of the particle size distribution on the solid-state sintering and their mechanical properties. The sintering kinetics was determined by dilatometry at temperatures from 900 to 1260°C. The mechanical properties of the sintered samples were evaluated by microhardness and compression tests. The sintering kinetics indicated that the predominant mechanism depends on the relative density irrespective of the particle size used. The mechanical properties of the sintered samples are adversely affected by increasing pore volume fraction. The elastic Young's modulus and yield stress follow a power law function of the relative density. The fracture behavior after compression is linked to the neck size developed during sintering, exhibiting two different mechanisms of failure: interparticle neck breaking and intergranular cracking in samples with relative densities below and above of 90%, respectively. The main conclusion is that relative density is responsible for the kinetics, mechanical properties, and failure behavior of Ti6 Al4 V powders.

关键词： Ti6Al4V powders dilatometry microhardness sintering kinetics compression failure behavior

Approximating home ranges of humpback and fin whales in Drake Passage and Antarctica

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Advances in Polar Science 2020年第4期31卷 248-257页

作者： joséluis ORGEIRA Facundo ALVAREZ Departamento Biología de los Predadores Tope Instituto Antártico Argentino.Buenos AiresArgentina Programa de pós-graduação em Ecologia e Conservação.Campus de Nova Xavantina.Universidade do Estado de Mato Grosso Brasil

Identifying home ranges—those areas traversed by individuals in their normal foraging,mating,and parenting activities—is an important aspect of cetacean *** these ranges facilitates identification of resource use and *** and humpback whales occur in Antarctica during the austral summer,but information regarding their home ranges is *** opportunistically collected whale sighting data from eight consecutive summer seasons spanning 2010–2017,we approximate the home ranges of humpback and fin whales around Drake Passage(DRA),West of Antarctic Peninsula(WAP),South Shetland Islands(SSI),an area northwest of the Weddell Sea(WED),and around the South Orkney Islands(SOI).Approximate home ranges are identified using Kernel Density Estimation(KDE).Most fin whales occurred north and northwest of the SOI,which suggests that waters near these islands support concentrations of this *** humpback whales were observed around the SSI,but unlike fin whales,their distributions were highly variable in other *** suggests spatial segregation in areas where both species exist such as SOI,SSI,and *** redundancy analysis(pRDA)suggests that the distributions of these species are more affected by spatial variables(latitude,longitude)than by local scale variables such as sea surface temperature and *** study presents a visual approximation of the home ranges of fin and humpback whales,and identifies variation in the effects of space and environmental variables on the distributions of these whales at different spatial scales.

关键词： humpback whale fin whale home range Antarctica Drake Passasge

Effect of Exogenous Melatonin on Seed Germination and Seedling Growth in Melon(Cucumis melo L.) Under Salt Stress

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Horticultural Plant Journal 2019年第2期5卷 79-87页

作者： josé luis Casta?ares Carlos Alberto Bouzo Plant Physiology Laboratory Department of Basic Sciences Universidad Nacional de Luján Laboratory of Research in Physiology and Plant Molecular Biology Facultad de Ciencias Agrarias Universidad Nacional del Litoral

An investigation was carried out to evaluate the effect of different application forms and concentrations of melatonin on germination and initial growth of melon plants in several different salinity conditions. We evaluated germination percentage and growth of seedlings and measured total chlorophyll content, relative electrolyte leakage, peroxidase activity, root viability, proline concentration, relative water content,Na^+/K^+ratio in green parts and K^+leakage from roots. Seed germination percentage under salt stress increased with treatments of 10 and50 μmol·L^(-1) melatonin. Seed treatment and plant watering with melatonin at 50 μmol·L^(-1) improved growth parameters and plants showed higher chlorophyll content as well as better biochemical parameters than non-treated plants. Results suggest that melatonin can alleviate the effect of salt stress during seed germination and first stages of plant development.

关键词： melon melatonin salt stress germination antioxidation

A NEW APPROACH TO SOLVE SYSTEMS OF LINEAR EQUATIONS

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Journal of Computational Mathematics 2001年第4期19卷 445-448页

作者： V á squez, luis V á squez-Poletti, jos é L. Universidad Complutense 西班牙 E-28040 Universidad Pontificia Comillas 西班牙 E-28015

Presents a study which proposed an iterative approach to solve systems of linear equations. Definition of two families of convergent iterative methods; Features of the iterative method; Application of the method to a ... 详细信息

关键词： Iterative method Linear systems Classical dynamics.

A methodology for assessing the urban supply of on-street delivery bays

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Green Energy and Intelligent Transportation 2022年第3期1卷 63-72页

作者： Antonio Comi joséluis Moura Sara Ezquerro University of Rome Tor Vergata RomeItaly University of Cantabria SantanderSpain

The loading and unloading operations carried out by transport and logistics operators have a strong impact on city mobility if they are not performed *** loading/unloading bays,i.e.,delivery bays(DB),are not available for freight vehicle operations,operators may opt to double park or park on the sidewalk where there is no strong enforcement of these laws,with significant impact on *** paper proposes a methodology for verifying and designing the number of delivery bays needed for freight vehicles for not interfere with cars or *** methodology consists of two stages:in the first stage,an initial estimation is made using queueing ***,in the second stage,using such tentative scenario,in order to take into account the system stochasticity involving different entities,a discrete event simulation is performed to more realistically verify and upgrade(if necessary)the number of delivery bays to obtain the expected *** methodology was applied in the inner area of Santander(Spain).The study area was subdivided into 29 zones where the methodology was applied *** results indicated that none of these zones currently have an optimal number of delivery bays to satisfy *** some zones,there is an excess of delivery bays,although in most of them,there is a deficit which can cause significant impacts on *** method proposed can be an effective tool to be used by city planners for improving freight operations in urban areas limiting the negative impacts produced in terms of internal and external costs.

关键词： Urban freight transportation On-street delivery bays Discrete event simulation City logistics Urban goods movements

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer M.Colón-Mercado Aranza I.Torrado-Tapias Iris K.Salgado jose M.Santiago Samuel E.Ocasio Rivera Dina P.Bracho-Rincon luis H.Pagan Rivera Jorge D.Miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Breeding effects on the genotype×environment interaction for yield of durum wheat grown after the Green Revolution:The case of Spain

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The Crop Journal 2020年第4期8卷 623-634页

作者： Fadia Chairi Nieves Aparicio Maria Dolores Serret josé luis Araus Section of Plant Physiology University of BarcelonaBarcelonaSpain AGROTECNIO(Center of Research in Agrotechnology) LleidaSpain Instituto de Tecnología Agraria de Castilla y León(ITACyL) ValladolidSpain

This study evaluates the changes caused by breeding in the genotype by environment(G×E)interaction of the durum wheat varieties most widely cultivated in Spain after the Green Revolution.A set of 12 cultivars was tested in 27 environments,which are understood as the combination of different sites,years,and treatments(water regime and planting dates),representative of the durum wheat growing conditions in Spain with average grain yields(GY)ranging between 2.8 and 9.1 Mg ha^-*** most important environmental factors affecting the G×E interaction for yield were themaximum and the mean temperature during the entire crop *** improvement in genetic yield was observed in warm environments and under optimal water conditions that resemble those where the germplasm originated(essentially as advanced lines)before its release in ***,the adaptation of semi-dwarf durum in Spain has shown a tendency to specific adaptation rather than large-scale *** different patterns of selection have been reported due the G×E interaction and changes in the ranking of genotypes:in the high yielding environments(GY>5 Mg ha^-1),plants favor increased water uptake,with higher levels of transpiration and more open stomata(more negative values of carbon isotope composition,δ^13 C,and higher canopy temperature depression,CTD),whereas,in low yielding environments(GY<5 Mg ha^-1)plants close their stomata and favor greater water use efficiency(less negativeδ^13 C values and lower CTD values).

关键词： breeding cultivar dwarf