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Out of Africa: Miocene Dispersal, Vicariance, and Extinction within Hyacinthaceae Subfamily Urgineoideae

Journal of Integrative Plant biology 2013年第10期55卷 950-964页

作者： Syed Shujait Ali Martin Pfosser Wolfgang Wetschnig Mario Martínez Azorín manuel b.crespo Yan Yu Institute of Plant Sciences Karl Franzens University Graz biocenter Linz Institute of biotechnology and Microbiology University of Swat CIbIO (Instituto Universitario de la biodiversidad) Universidad de Alicante Key Laboratory of bio Resources and Eco Environment of Ministry of Education College of Life Sciences Sichuan University

Disjunct distribution patterns in plant lineages are usually explained according to three hypotheses： vicariance, geodispersal, and long-distance dispersal. The role of these hypotheses is tested in Urgineoideae （Hyacinthaceae）, a subfamily disjunctly distributed in Africa, Madagascar, India, and the Mediterranean region. The potential ancestral range, dispersal routes, and factors responsible for the current distribution in Urgineoideae are investigated using divergence time estimations. Urgineoideae originated in Southern Africa approximately 48.9 Mya. Two independent dispersal events in the Western Mediterranean region possibly occurred during Early Oligocene and Miocene （29.9-8.5 Mya） via Eastern and Northwestern Africa. A dispersal from Northwestern Africa to India could have occurred between 16.3 and 7.6 Mya. Vicariance and extinction events occurred approximately 21.6 Mya. Colonization of Madagascar occurred between 30.6 and 16.6 Mya, after a single transoceanic dispersal event from Southern Africa. The current disjunct distributions of Urgineoideae are not satisfactorily explained by Gondwana fragmentation or dispersal via boreotropical forests, due to the younger divergence time estimates. The flattened winged seeds of Urgineoideae could have played an important role in long- distance dispersal by strong winds and big storms, whereas geodispersal could have also occurred from Southern Africa to Asia and the Mediterranean region via the so-called arid and high-altitude corridors.

关键词： bayesian binary method bayesian divergence estimates biogeography disjunct distribution time-event curve Urgineoideae.

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Clinical significance of"anti-Hbc alone"in human immunodeficiency virus-positive patients

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World Journal of Gastroenterology 2009年第10期15卷 1237-1241页

作者： M~aTeresa Pérez-Rodríguez bernardo Sopea manuel crespo Alberto Rivera Teresa González del blanco Antonio Ocampo César Martínez-Vázquez Infectious Diseases Unit Internal Medicine DepartmentXeral-Cíes University Hospital36204 VigoSpain Faculty of Medicine University of Santiago de Compostela15705 Santiago de CompostelaA CoruaSpain Infectious Diseases Department Vall d' Hebron Hospital08035 BarcelonaSpain Microbiology Department Xeral-Cíes University Hospital36204 VigoSpain

AIM： TO determine the prevalence and clinical relevance of isolated antibodies to hepatitis b core antigen as the only marker of infection （“anti-Hbc alone”） among human immunodeficiency virus （HIV） type-1 infected patients. Occult hepatitis b infection frequency was also evaluated. METHODS： Three hundred and forty eight histories from 2388 HIV-positive patients were randomly reviewed. Patients with serological markers of hepatitis b virus （HbV） infection were classified into three groups： past hepatitis, ＂anti-Hbc alone＂ and chronic hepatitis. Determination of DNA from HbV, and RNA and genotype from hepatitis C virus （HCV） were performed on ＂anti-Hbc alone＂ patients. RESULTS： One hundred and eighty seven （53.7%） HIV-positive patients had markers of HbV infection： 118 past infection （63.1%）, 14 chronic hepatitis （7.5%） and 55 ＂anti-Hbc alone＂（29.4%）. Younger age [2.3-fold higher per every 10 years younger; 95% confidence intervals （Cl） 1.33-4.00] and antibodies to HCV infection [odds ratio （OR） 2.87; 95% CI 1.10-7.48] were factors independently associated with the ＂anti-Hbc alone＂ pattern. No differences in liver disease frequency were detected between both groups. Serum levels of anti-Hbs were not associated with HCV infection （nor viral replication or HCV genotype）, or with HIV replication or CD4 level. No ＂anti-Hbc alone＂ patient tested positive for HbV DNA. CONCLUSION：＂Anti-Hbc alone＂ prevalence in HIM- positive patients was similar to previously reported data and was associated with a younger age and with antibodies to HCV infection. In clinical practice, HbV DNA determination should be performed only in those patients with clinical or analytical signs of liver injury,

关键词： Human immunodeficiency virus "Anti-Hbcalone" Occult hepatitis Hepatitis b virus DNA Liverdisease

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Thermo-electro-mechanical microstructural interdependences in conductive thermoplastics

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npj Computational Materials 2023年第1期9卷 955-965页

作者： Javier crespo-Miguel Sergio Lucarini Angel Arias Daniel Garcia-Gonzalez Department of Continuum Mechanics and Structural Analysis Universidad Carlos III de MadridAvda.de la Universidad 3028911 LeganésMadridSpain Department of Civil and Environmental Engineering Imperial College of LondonSouth Kensington CampusLondon SW72AZUK

Additive manufacturing has enabled the design of thermoplastic components that provide structural support,electrical conductivity and heat generation modulated by mechanical *** mechanisms and interplays that govern the material response at the microstructural level remain,however,***,we develop an experimental method to characterise conductive filaments from a combined mechanical,electrical and thermal *** approach is used to unravel exciting material interplays of conductive polylactic *** overcome experimental limitations that prevent a complete microstructural analysis of the problem,we develop a full-field homogenisation framework and implement it for finite *** framework accounts for viscoplasticity,electrical and thermal conduction,convection and heat generation via Joule effect,as well as for the interdependences between *** experimental validation,the framework is applied to virtually optimise fabrication requirements to obtain desired properties in final products,i.e.,stiffer products,filaments with higher conductivities or with better sensing capabilities.

关键词： conductive electrical overcome

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Slowβrelaxation in La-based metallic glasses based on mechanical spectroscopy measurements

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Journal of Iron and Steel Research International 2017年第4期24卷 397-401页

作者： Ji-chao Qiao Jean-marc Pelletier Ning Li Daniel crespo Yao Yao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072ShaanxiChina Universite de Lyon MATEISUMR-CNRS5510Bat.B.PascalINSA LyonF-69621 Villeurbanne cedexFrance Department of Materials Science and Engineering State Key Laboratory for Materials Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074HubeiChina Departament de Fisica EETACUniversitat Politecnica de CatalunyaCastelldfels 08860BarcelonaSpain

Dynamic mechanical relaxations of La-based metallic glasses were investigated by mechanical *** the framework of the mixing enthalpy of constituent atoms,it was found thatβrelaxation was less evident by the addition of Cu to replace Ni in the LaCuNiAl glassy *** introducing Cu into the LaNiAl metallic glass,the mixing enthalpy was less negative,which led to weakerβrelaxation of the metallic ***αrelaxation of the La-based metallic glasses could be described by a Kohlrausch-Williams-Watts（KWW）function with a Kohlrausch exponentβKWW around *** should be noted that physical aging above the glass transition temperature Tginduced a decrease ofβrelaxation intensity in the La-based metallic glass.

关键词： Metallic glass Mechanical relaxation βrelaxation Mixing enthalpy

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Empowered Stakeholders: Female University Students’ Leadership During the COVID-19-Triggered On-campus Evictions in Canada and the United States

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International Journal of Disaster Risk Science 2021年第4期12卷 581-592页

作者： Haorui Wu Marla Perez-Lugo Cecilio Ortiz Garcia Frances Gonzalez crespo Adriana Castillo Canada Research Chair in Resilience School of Social WorkDalhousie UniversityHalifaxNSB3H 4R2Canada Natural Hazards Center University of Colorado BoulderBoulderCO80309USA Department of Social Sciences University of Puerto Rico MayagüezMayagüezPR00682USA The RISE Network MayagüezPR00680USA

The study of disaster-specific leadership of female university students has been largely neglected,especially during on-campus emergency eviction and *** on the COVID-19-triggered,on-campus evictions across Canada and the United States,this cross-national partnership examined the out-of-province/state and international female university students’leadership during the entire eviction *** in-depth interviews,this study revealed the female university students’leadership behaviors during three stages:(1)pre-eviction:their self-preparedness formed an emotional foundation to support others;(2)peri-eviction:their attitude and leadership behavior enabled them to facilitate(psychologically and physically)their peers’eviction process;and(3)post-eviction:they continued to support their peers virtually and raised the general public’s awareness regarding the plight of vulnerable and marginalized *** article argues that the female university students’leadership that emerged during the eviction process became complementary to and even augmented the universities’official efforts and *** leadership represents empirical evidence that contributes to the existing literature on gender and leadership by demonstrating female youth as empowered stakeholders rather than as merely passive *** studies could develop detailed stratification of gender and age dimensions in order to portray a more comprehensive picture of the younger generation’s leadership in hazards and disaster research and practice.

关键词： Canada COVID-19 Female leadership Gender and disaster On-campus evictions United States University students

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Secondary relaxation and dynamic heterogeneity in metallic glasses：A brief review

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Chinese Physics b 2017年第1期26卷 32-41页

作者： J C Qiao[[ Q Wang D crespo Y Yang J M Pelletier School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi＇an 710072 China Centre for Advanced Structural Materials Department of Mechanical and Biomedical Engineering City University of Hong Kong Kowloon Tong Kowloon Hong Kong China Universite de Lyon MATEIS UMR CNRS5510 Bat. B. Pascal INSA-Lyon F-69621 Villeurhanne cedex France Key Laboratory for Structures Institute of Materials Science Shanghai University Shanghai 200444 China Departament de Fisica EETAC Universitat Politecnica de Catalunya 08860-Castelldfels Barcelona Spain

Understanding mechanical relaxation, such as primary（α） and secondary（β） relaxation, is key to unravel the intertwined relation between the atomic dynamics and non-equilibrium thermodynamics in metallic glasses. At a fundamental level, relaxation, plastic deformation, glass transition, and crystallization of metallic glasses are intimately linked to each other, which can be related to atomic packing, inter-atomic diffusion, and cooperative atom movement. Conceptually, βrelaxation is usually associated with structural heterogeneities intrinsic to metallic glasses. However, the details of such structural heterogeneities, being masked by the meta-stable disordered long-range structure, are yet to be understood. In this paper, we briefly review the recent experimental and simulation results that were attempted to elucidate structural heterogeneities in metallic glasses within the framework of β relaxation. In particular, we will discuss the correlation amongβ relaxation, structural heterogeneity, and mechanical properties of metallic glasses.

关键词： metallic glass structural heterogeneity mechanical property secondary relaxation

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Morphometrics confirms the conspecific between blaptica dubia(Serville) and b. interior Hebard(blattodea:blaberidae)

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Zoological Systematics 2019年第2期44卷 111-122页

作者： María Marta González Alejandra del Carmen Valverde Mónica Sandra Iglesias Francisco Antonio crespo Laboratorio de Artrópodos Departamento de Biodiversidad y Biología Experimental Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires Pabellón Ⅱ Ciudad Universitaria Centro de diagnóstico e investigación en endemo-epidemias. Administración nacional de laboratorios e institutos de salud "Dr. Carlos G. Malbrán"

blaptica dubia(Serville, 1838) and b. interior Hebard, 1921 were considered to be cryptic species. The characteristics originally proposed for their identification are not *** the relationship between the two species should be re-considered. As a comparative approach and to analyze intraspecific variability, morphological and morphometric methods were performed. Traditional and new characters such as wing shape and pronotum contour were utilized. We found significant differences between both species(p but there was an overlap of values. We did not find differences in the body measurements or in the shape and size of the pronotum between the species. The variability gradient does not allow an accurate identification of species neither with the male genitalia or the pronotal *** on the obtained results, b. interior Hebard 1921 is considered to be a junior synonym of b. dubia(Serville, 1838).

关键词： Cockroaches pronotum genitalia geometric morphometric analysis synonymy

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Analysis of the hydrological safety of dams combining two numerical tools:Iber and DualSPHysics

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Journal of Hydrodynamics 2018年第1期30卷 87-94页

作者： J.González-Cao O.García-Feal J.M.Domínguez A.J.C.crespo M.Gómez-Gesteira Environmental Physics Laboratory (EPHYSLAb) Universidade de Vigo Campus AsLagoas

The upgrade of the hydrological safety of dams is a critical issue to avoid failures that can dramatically affect people and assets. This paper shows a numerical methodology to analyse the safety of the belesar dam（NW, Spain） based on two different numerical codes. First, a mesh-based code named Iber, suited to deal with large 2-D domains, is used to simulate the impoundment. The initial conditions and the inlet provided to Iber correspond to the maximum water elevation and the maximum expected inflow to the impoundment defined in the technical specifications of the dam, which are associated to the more hazardous operation conditions of the dam. Iber provides information about the time needed for water to attain the crest of the dam when floodgates are closed. In addition, it also provides the velocity of discharge when gates are opened. Then, a mesh-free code named DualSPHysics, which is especially suited to deal with complex and violent 3-D flows, is used to reproduce the behaviour of one of the spillways of the dam starting from the results obtained with Iber, which are used as inlet conditions for DualSPHysics. The combined results of both model show that the left spillway can discharge the surplus of water associated to the maximum inflow to the reservoir if the gates of the spillways are opened before the overtopping of the dam was observed. In addition, water depth measured on the spillway is considerably lower than the lateral walls, preventing overtopping. Finally, velocities at different points of the spillway showed to be in good agreement with theoretical values.

关键词： Hydrological safety dam numerical simulation Iber DualSPHysics

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Analysis of the anelastic deformation of high-entropy Pd_(20)Pt_(20)Cu_(20)Ni_(20)P_(20) metallic glass under stress relaxation and recovery

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Journal of Materials Science & Technology 2022年第12期107卷 82-91页

作者： Y.J.Duan L.T.Zhang T.Wada H.Kato E.Pineda D.crespo J.M.Pelletier J.C.Qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China Department of Physics Institute of Energy TechnologiesUniversitat Politècnica de CatalunyaBarcelona 08019Spain Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Universitéde Lyon MATEISUMR CNRS5510Bat.B.PascalINSA-LyonF-69621 Villeurbanne CedexFrance

The anelastic deformation behavior of Pd_(20)Pt_(20)Cu_(20)Ni_(20)P_(20) high-entropy metallic glass was probed by monitoring the stress relaxation and recovery processes. The stress relaxation under consecutive strain steps can be described by the Kohlrausch-Williams-Watts(KWW) function. In addition, considering a hierarchy of relaxation processes related to the structural heterogeneity, a constitutive model is proposed in order to describe the whole process of stress relaxation and determine the contribution of different time scales. Moreover, a crossover from stochastic activation to percolation of flow defects with the ultimate strain can be observed during stress relaxation process. The anelastic recovery process after a strain step is studied as a function of the initial strain level and characterized by means of a direct spectrum analysis. The peaks in the recovery time-spectra revealed the evolution of flow defects in Pd_(20)Pt_(20)Cu_(20)Ni_(20)P_(20) high-entropy metallic glass. The understanding of the atomic free-volume zones effect and the anelastic deformation provides important insight into how atomic structural features affect the deformation behavior of high-entropy metallic glasses, and may provide a new avenue into the improvement of their mechanical properties.

关键词： High-entropy metallic glass Stress relaxation Anelastic deformation Flow defects Free-volume zones

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Dynamic mechanical relaxation behavior of Zr_(35)Hf_(17.5)Ti_(5.5)Al_(12.5)Co_(7.5)Ni_(12)Cu_(10)high entropy bulk metallic glass

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Journal of Materials Science & Technology 2021年第24期83卷 248-255页

作者： L.T.Zhang Y.J.Duan T.Wada H.Kato J.M.Pelletier D.crespo E.Pineda J.C.Qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China Institute for Materials Research Tohoku UniversitySendai980-8577Japan Universitéde Lyon MATEISUMR CNRS5510Bat.B.PascalINSA-LyonF-69621Villeurbanne CedexFrance Department of Physics Barcelona Research Center in Multiscale Science and TechnologyInstitute of Energy TechnologiesUniversitat Politècnica de Catalunya08019BarcelonaSpain

Non-equiatomic high entropy bulk metallic glasses were reported recently and show unique mechanical and physical *** mechanical relaxation behavior of Zr_(35)Hf_(17.5)Ti_(5.5)Al_(12.5)Co_(7.5)Ni_(12)Cu_(10)high entropy bulk metallic glass was investigated by dynamic mechanical analysis(DMA)and the mechanical spectra could be well described by the quasi-point defects(QPD)*** to typical metallic glasses,the intensity of theβrelaxation of Zr_(35)Hf_(17.5)Ti_(5.5)Al_(12.5)Co_(7.5)Ni_(12)Cu_(10)high entropy bulk metallic glass is lower due to the sluggish *** the same time,the correlation factor is higher than that of conventional metallic glasses and this is ascribed to the high configuration *** parallel,physical aging below the glass transition temperature leads to a decrease of atomic mobility,caused by a decrease of the concentration of defects.

关键词： High entropy bulk metallic glass Mechanical relaxation Quasi-point defects Physical aging

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