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多道次等径通道挤压后TWIP钢的本构模型（英文）

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材料热处理学报 2017年第2期38卷 185-190页

研究了通过等径通道挤压技术加工后的诱导孪晶塑性变形钢(TWIP钢)的力学性能,并且通过Ludwik,Hollomon以及Swift三种本构模型对拉伸真实应力应变曲线进行了拟合。实验结果表明:随着挤压道次的增加,屈服强度以及极限抗拉强度不断升高,而... 详细信息

研究了通过等径通道挤压技术加工后的诱导孪晶塑性变形钢(TWIP钢)的力学性能,并且通过Ludwik,Hollomon以及Swift三种本构模型对拉伸真实应力应变曲线进行了拟合。实验结果表明:随着挤压道次的增加,屈服强度以及极限抗拉强度不断升高,而塑性,抗拉韧性不断下降。Ludwik,Hollomon以及Swift三种本构模型对于真实应力应变曲线的拟合程度较好,并且本文给出了各模型中的拟合参数。拟合参数中,本文着重讨论了应变硬化系数n随着挤压道次的升高而降低的原因。

关键词： TWIP钢等径通道挤压技术(ECAP) 力学性能本构模型

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晶粒细化对TWIP钢力学性能与织构的影响（英文）

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材料热处理学报 2016年第8期37卷 132-138页

作者：王雷 benito j a CALVO j CABRERA j M 加泰罗尼亚理工大学工业工程学院材料科学与冶金工程系Barcelona 08028Spain 西安石油大学材料科学与工程学院陕西西安710065 加泰罗尼亚理工大学工业工程学院材料科学与冶金工程系Barcelona 08036Spain 曼雷萨科技中心 Manresa 08242Spain

奥氏体高锰钢（15%-30%）呈现出孪晶诱导塑性变形机制,并在拉伸试验中表现出很好的强度-塑性性能,因此在汽车工业结构件应用中有很大潜力。最近几年,对于TWIP钢不同方面的研究受到了高度重视。之前一些综述文章关注于TWIP钢的基本知识,... 详细信息

奥氏体高锰钢（15%-30%）呈现出孪晶诱导塑性变形机制,并在拉伸试验中表现出很好的强度-塑性性能,因此在汽车工业结构件应用中有很大潜力。最近几年,对于TWIP钢不同方面的研究受到了高度重视。之前一些综述文章关注于TWIP钢的基本知识,而非晶粒细化方法的影响。本文主要综述了通过冷轧以及强塑性变形方法引起的力学性能改善以及织构变化。基于之前的研究,通过冷轧以及强塑性变形方法,平均晶粒尺度可以急剧地减小,同时屈服强度和极限抗拉强度将会大幅升高。这个现象可以归因于变形过程引起的孪晶演化。另一方面,在冷轧变形后,Goss和Brass织构会逐步形成。

关键词： TWIP钢冷轧 ECAP 力学性能织构

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Hurwitz定理的一个简单证明

数学译林 2007年第3期26卷 287-288页

作者： Manuel benito j. javier Escribano 王义东(译) 陆柱家(校)

我们利用Brocot序列给出著名的Hurwitz定理的一个简单证明．

关键词： Hurwitz 简单证明定理

Mineral dust resuspension under vibration: Onset conditions and the role of humidity

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Particuology 2020年第3期18卷 112-119页

作者： F.j.Balladore j.G.benito R.O.Unac A.M.Vidales Departamento de Mineria Facultad de Ciencias Fisico Matematicas y NaturalesUniversidad Nacional de San LuisChacabuco 917D5700HHWSan LuisArgentina INFAP CONICETDepartamento de FisicaFacultad de Ciencias Fisico Matematicas y NaturalesUniversidad Nacional de San LuisEjercito de los Andes 950D5700HHWSan LuisArgentina

The vibration of dusty surfaces inevitably causes re-entrainment of particles into the *** that movement of mineral dust particles deposited on a surface begins at a critical frequency (fc) and amplitude,an experimental laboratory study was conducted to determine the onset conditions for resuspension of a vibrated granular *** determined the resuspension state diagram as a function of frequency and amplitude of a sinusoidal vibration,the granulometry of the dust and the thickness of the soil *** mitigation effect of humidity was also *** frequencies ranged between 2.5 and 23 Hz when amplitudes were less than 12 *** results were independent of bed thickness and perturbation *** all particle sizes observed,fc decreased monotonically with A,contrasting with behavior observed for individual *** dry samples,fe for large size classes was markedly less when A was greater than 6 mm;while thefc for fine fractions only decreased once amplitudes reached 10 *** with wet granular soils demonstrated that wetting above an optimum humidity did not necessarily impede movement and caused *** study provides guidelines for managing resuspension of granular soils subjected to vibrations.

关键词： Resuspension Vibration Granular soil Mineral dust Critical frequency Humidity

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迟发的特发性震颤与痴呆相关

世界核心医学期刊文摘(神经病学分册) 2006年第11期 57-57页

作者： benito-Leóon j Louis E.D Bermejo-Pareja F 郭俊 Avda. C. 73 portal 3 7 Izquierda E-28820 Coslada Madrid Spain Dr.

OBjECTIVE: To determine whether essential tremor (ET) is associated with prevalent dementia. METHODS: The authors identified all persons with dementia and ET in a population-based study in central Spain (the Neurological Disorders in Central Spain [NEDICES] Study). Dementia was diagnosed using the Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria. RESULTS: Thirty-one (11.4%) of 273 ET cases had dementia vs 204 (6.0%) of 3,382 non-ET subjects (controls) (odds ratio [OR] = 2.00, 95%CI = 1.34 to 2.98, p = 0.001). In a model that adjusted for age, stroke, and educational level, OR = 1.35, 95%CI = 0.87 to 2.18, and p = 0.17. In an adjusted model, ET cases with tremor onset after age 65 were 70%more likely to be demented than were controls (OR = 1.70, 95%CI = 1.04 to 2.76, p = 0.03), whereas ET cases with tremor onset at age ≤65 and controls were equally likely to be demented (OR = 0.38, 95%CI = 0.09 to 1.73, p = 0.21). CONCLUSIONS: Older-onset essential tremor (ET) was associated with dementia. Prospective studies are required to elucidate the association between ET and dementia.

关键词：特发性震颤迟发 ET

Prey availability, prey selection, and trophic niche width in the lizard Psammodromus algirus along an elevational gradient

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Current Zoology 2018年第5期64卷 603-613页

作者： Gregorio MORENO-RUEDA Elena MELERO Senda REGUERA Francisco j, ZAMORA-CAMACHO Ines ALVAREZ-benito Departamento de Zoologla Facultad de Ciencias Universidad de Granada Granada E-18071 Spain Departamento de Biogeografia y Carnbio Global Museo Nacional de Ciencias Naturales-CSIC C/Jose Gutierrez Abascal 2 E-28006 Madrid Spain

Mountains imply enormous environmental variation, with alpine habitats entailing harsh environ- ments, especially for ectotherms such as lizards. This environmental variability also may imply variation in prey availability. However, little is known about how lizard trophic ecology varies with elevation. In this study, we analyze diet, prey availability, prey selection, and trophic niche width in the lacertid lizard Psammodromus algirus along a 2,200-m elevational gradient in the Sierra Nevada （SE Spain）. The analysis of fecal samples has shown that Orthoptera, Formicidae, Hemiptera, Coleoptera, and Araneae are the main prey, although, according to their abundance in pitfall traps, Formicidae and Coleoptera are rejected by the lizard whereas Orthoptera, Hemiptera, and Araneae are preferred. Prey abundance and diversity increase with elevation and diet subtly varies along with the elevational gradient. The consumption of Coleoptera increases with elevation probably as a consequence of the lizard foraging more in open areas while basking. The electivity for Araneae increases with elevation. Araneae are rejected in the lowlands--where they are rela- tively abundant--whereas, at high elevation, this lizard positively selects them, despite they being less abundant. The lizard trophic niche width expands with elevation due to concomitant greater prey diversity and hence this lizard feeds on more prey types in highlands. Although no sex difference in diet has been found, the trophic niche is broader in females than males. As a whole, alpine lizards show a trophic niche simitar to that found at lower elevat（ons, suggesting that P. algirus is well adapted to the harsh environment found in alpine areas.

关键词： alpine habitats arthropods mountain ecology niche variation hypothesis trophic ecology

Inconsistent interspecific and intraspecific differentiation of climate envelopes in a subtropical tree

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journal of Plant Ecology 2019年第1期12卷 176-185页

作者： Qiuchi Wan Zhuo Zheng Marta benito-Garzón Rémy j.Petit School of Earth Science and Geological Engineering Sun Yat-sen University135 Xingang RoadHaizhu DistrictGuangzhou 510275China Biogeco INRAUniversity of Bordeaux69 Arcachon Road33610 CestasFrance

Aims Comparisons of climate envelopes among species have shown that niche conservatism tends to break down over ***,we use the Asian tree genus Platycarya(juglandaceae)as a case study to test this tendency at relatively short timescales in a single ***,together with a reanalysis of the extant literature,should help evaluate prospects of using correlations between climate and spe-cies occurrence data to infer evolutionary *** We rely on species distribution models(SDMs)and multivari-ate analyses to compare current and past(Last Glacial Maximum~21ka)climatic envelopes between the two extant Platycarya spe-cies(Platycarya strobilacea and Platycarya longipes)and between mainland and Taiwan populations of ***,paying particu-lar attention to autocorrelation *** also review interpreta-tions provided in similar studies comparing climate envelopes between and within species,including in studies involving native and introduced populations of the same *** Findings We find intraspecific but not interspecific differentiation in climate envelopes of Platycarya,despite the prediction that niche differen-tiation should be stronger between older *** review also suggests that differentiation in climate envelopes need not imply rapid evolutionary *** SDMs can be used to raise evolutionary hypotheses to be validated with other data,we con-clude that it should not be used to directly infer short-term evolu-tionary processes.

关键词： climate envelope Last Glacial Maximum evolution Platycarya species distribution models

Role of chemokines and their receptors in viral persistence and liver damage during chronic hepatitis C virus infection

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World journal of Gastroenterology 2008年第47期14卷 7149-7159页

作者： juan R Larrubia Selma benito-Martínez Miryam Calvino Eduardo Sanz-de-Villalobos Trinidad Parra-Cid Department of Gastroenterology Guadalajara University HospitalUniversity of AlcaláDonante de Sangre st.19002 GuadalajaraSpain Guadalajara University Hospital University of AlcaláDonante de Sangre st.19002 GuadalajaraSpain

Chemokines produced in the liver during hepatitis C virus(HCV) infection induce migration of activated T cells from the periphery to infected *** milieu of chemokines secreted by infected hepatocytes is predominantly associated with the T-helper cell/Tc1 T cell(Th1/Tc1) *** chemokines consist of CCL3(macrophage inflammatory protein-1α;MIP-1α),CCL4(MIP-1β),CCL5(regulated on activation normal T cell expressed and secreted;RANTES),CXCL10(interferon-γ-inducible protein-10;IP-10),CXCL11(interferon-inducible T-cell α chemoattractant;I-TAC),and CXCL9(monokine induced by interferon γ;Mig) and they recruit T cells expressing either CCR5 or CXCR3 chemokine *** and peripheral blood levels of these chemokines are increased during chronic hepatitis *** interaction between chemokines and their receptors is essential in recruiting HCV-specific T cells to control the *** the adaptive immune response fails in this task,non-specific T cells without the capacity to control the infection are also recruited to the liver,and these are ultimately responsible for the persistent hepatic *** modulation of chemokine receptor expression and chemokine secretion could be a viral escape mechanism to avoid specific T cell migration to the liver during the early phase of infection,and to maintain liver viability during the chronic phase,by impairing non-specific T cell *** chemokines and their receptors correlate with liver damage,and CXCL10(IP-10) and CXCR3 levels have shown a clinical utility as predictors of treatment response *** regulation of chemokines and their receptors could be a future potential therapeutic target to decrease liver inflammation and to increase specific T cell migration to the infected liver.

关键词： Chemokines Chemokine receptors Hepatitis C virus Viral hepatitis pathogenesis Persistentinfection Viral escape mechanism

Costimulatory molecule programmed death-1 in the cytotoxic response during chronic hepatitis C

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World journal of Gastroenterology 2009年第41期15卷 5129-5140页

作者： juan Ramón Larrubia Selma benito-Martínez joaquín Miquel Miryam Calvino Eduardo Sanz-de-Villalobos Trinidad Parra-Cid Translational Hepatology Unit Guadalajara University Hospital University of Alcalá

Hepatitis C virus（HCV）-specific CD8^＋ T cells play an important role in the resolution of HCV infection. Nevertheless, during chronic hepatitis C these cells lack their effector functions and fail to control the virus. HCV has developed several mechanisms to escape immune control. One of these strategies is the upregulation of negative co-stimulatory molecules such us programmed death-1 （PD-1）. This molecule is upregulated on intrahepatic and peripheral HCV-specific cytotoxic T cells during acute and chronic phases of the disease, whereas PD-1 expression is low in resolved infection. PD-1 expressing HCV-specific CD8^＋ T cells are exhausted with impairment of several effector mechanisms, such as： type-1 cytokine production, expansion ability after antigen encounter and cytotoxic ability. However, PD-1 associated exhaustion can be restored by blocking the interaction between PD-1 and its ligand （PD-L1）. After this blockade, HCV-specific CD8^＋ T cells reacquire their functionality. Nevertheless, functional restoration depends on PD-1 expression level. High PD-l-expressing intrahepatic HCV-specific CD8^＋ T cells do not restore their effector abilities after PD-1/ PD-L1 blockade. The mechanisms by which HCV is able to induce PD-1 up-regulation to escape immune control are unknown. Persistent TCR stimulation by a high level of HCV antigens could favour early PD-1 induction, but the interaction between HCV core protein and gClq receptor could also participate in this process. The PD-1/PD-L1 pathway modulation could be a therapeutic strategy, in conjunction with the regulation of others co-stimulatory pathways, in order to restore immune response aclainst HCV to succeed in clearing the infection.

关键词： Chronic hepatitis Exhaustion Hepatitis C virus core Hepatitis C virus Programmed death-1 Programmed death-1 ligand