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Seismic fragility assessment of low-rise stone masonry buildings

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 87-97页

作者： Ahmad Abo-El-Ezz Marie-josé Nollet Miroslav Nastev Department of Construction Engineering école de technologie supérieureUniversity of Québec MontréalQCH3C 1K3Canada Geological Survey of Canada Natural Resources Canada490Rue de la CouronneQuébecQCG1K 9A9Canada

Many historic buildings in old urban centers in Eastern Canada are made of stone masonry reputed to be highly vulnerable to seismic *** risk assessment of stone masonry buildings is therefore the first step in the risk mitigation process to provide adequate planning for retrofit and preservation of historical urban *** paper focuses on development of analytical displacement-based fragility curves reflecting the characteristics of existing stone masonry buildings in Eastern *** old historic center of Quebec City has been selected as a typical study *** standard fragility analysis combines the inelastic spectral displacement,a structure-dependent earthquake intensity measure,and the building damage state correlated to the induced building *** proposed procedure consists of a three-step development process：（1） mechanics-based capacity model,（2） displacement-based damage model and（3） seismic demand *** damage estimation for a uniform hazard scenario of 2% in 50 years probability of exceedance indicates that slight to moderate damage is the most probable damage experienced by these stone masonry *** is also made with fragility curves implicit in the seismic risk assessment tools Hazus and *** shows the highest probability of the occurrence of no to slight damage,whereas the highest probability of extensive and complete damage is predicted with *** comparison shows the importance of the development of fragility curves specific to the generic construction characteristics in the study area and emphasizes the need for critical use of regional risk assessment tools and generated results.

关键词： seismic risk assessment fragility analysis stone masonry

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

Gromov Hyperbolicity of Riemann Surfaces

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Acta Mathematica Sinica,English Series 2007年第2期23卷 209-228页

作者： josé M.RODRíGUEZ EVa TOURIS Departamento de Matemáticas Universidad Carlos Ⅲ de MadridAvenida de la Universidad 3028911 LeganésMadridSpain

We study the hyperbolicity in the Gromov sense of Riemann surfaces. We deduce the hyperbolicity of a surface from the hyperbolicity of its ＂building block components＂. We also prove the equivalence between the hyperbolicity of a Riemann surface and the hyperbolicity of some graph associated with it. These results clarify how the decomposition of a Riemann surface into Y-pieces and funnels affects the hyperbolicity of the surface. The results simplify the topology of the surface and allow us to obtain global results from local information.

关键词： Gromov hyperbolicity hyperbolic Riemann surface

A Complete Diophantine Characterization of the Rational Torsion of an Elliptic Curve

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Acta Mathematica Sinica,English Series 2012年第1期28卷 83-96页

作者： Irene GARCíA-SELFA jos M.TORNERO Departamento de Matemáticas Universidad de HuelvaFacultad de Ciencias ExperimentalesCampus de El CarmenAvenida de las Fuerzas Armadass/n21071 HuelvaSpain Departamento de ' Algebra Universidad de SevillaP.O.116041080 SevillaSpain

We give a complete characterization for the rational torsion of an elliptic curve in terms of the （non-）existence of integral solutions of a system of diophantine equations.

关键词： Elliptic curves diophantine equations

Hilar cholangiocarcinoma

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World Journal of Gastrointestinal Oncology 2013年第7期5卷 113-114页

作者： josé M Ramia Department of Surgery Hospital Universitario de Guadalajara19002 GuadalajaraSpain

Hilar cholangiocarcinoma(HC) is a rare *** accounts for 2/3 of the tumors of the biliary ***,prognosis is very *** is the only therapy that offers the possibility of cure but is technically very *** recent improvements in the therapeutic strategies applied by multidisciplinary teams,survival rates in the different series currently range from 25% to 45%.A group of experts devoted to HC(pathologists,gastroenterologists,radiologists,surgeons and oncologists) have reviewed and updated every open question in HC in a special issue.

关键词： Cholangiocarcinoma Hilar Perihilar Klatskin Surgery Cancer Review

Hölder,Sobolev,weak-type and BMO estimates in mixed-norm with weights for parabolic equations

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Science China Mathematics 2021年第1期64卷 129-154页

作者： Pablo Raúl Stinga josé L.Torrea Department of Mathematics Iowa State UniversityAmesIA50011USA Departamento de Matemáticas Universidad Autónoma de MadridMadrid28049Spain

We prove weighted mixed-norm Lqt(W2,px)and Lqt(C2,αx)estimates for 10,x∈Rn.x∈Rn,The coefficients a(t)=(aij(t))are just bounded,measurable,symmetric and uniformly ***,we show strong,weak type and BMO-Sobolev estimates with parabolic Muckenhoupt *** is quite remarkable that most of our results are new even for the classical heat equation∂tu−Δu+u=f.

关键词： Calderón-Zygmund parabolic singular integrals weak type and BMO estimates representation formulas parabolic equations mixed-norm Sobolev and Schauder estimates

Hepatocyte transplantation program:Lessons learned andfuture strategies

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World Journal of Gastroenterology 2016年第2期22卷 874-886页

作者： Eugenia Pareja Ibars Miriam Cortes Laia Tolosa Maria joséGómez-Lechón Slivia López joséVicente Castell joséMir Unidad de Terapia Celular Hepatica Instituto de Investigación Sanitaria La FeHospital Universitario y Politécnico La Fe de Valencia46026 ValenciaSpain Unidad de Cirugía Hepato-Bilio-Pancreática y Trasplante Hepático Hospital Universitario y Politécnico La Fe de Valencia46026 ValenciaSpain Liver transplantation Institute of Liver StudiesKing’s College HospitalInstitute of Liver StudiesSE5 9RS LondonUnited Kingdom Unidad de Hepatologıa Experimental Instituto de Investigación Sanitaria La FeHospital Universitario y Politécnico La Fe de Valencia46026 ValenciaSpain CIBERehd FIS08036 BarcelonaSpain

This review aims to share the lessons we learned over time during the setting of the hepatocyte transplantation(HT) program at the Hepatic Cell Therapy Unit at Hospital La Fe in Valencia. New sources of liver tissue for hepatocyte isolation have been explored. The hepatocyte isolation and cryopreservation procedures have been optimized and quality criteria for assessment of functionality of hepatocyte preparations and suitability for HT have been established. The results indicate that:(1) Only highly viable and functional hepatocytes allow to recover those functions lacking in the native liver;(2) Organs with steatosis(≥ 40%) and from elderly donors are declined since low hepatocyte yields, viability and cell survival after cryopreservation, are obtained;(3) Neonatal hepatocytes are cryopreserved without significant loss of viability or function representing high-quality cells to improve human HT;(4) Cryopreservation has the advantage of providing hepatocytes constantly available and of allowing the quality evaluation and suitability for transplantation; and(5) Our results from 5 adults with acute liver failure and 4 from children with inborn metabolic diseases, indicate that HT could be a veryuseful and safe cell therapy, as long as viable and metabolically functional human hepatocytes are used.

关键词： Hepatocyte transplantation Hepatocyteisolation Cell therapy Inborn errors of metabolism Neonatal hepatocytes Cryopreservation

Severity of ulcerative colitis is associated with a polymorphism at diamine oxidase gene but not at histamine N-methyltransferase gene

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World Journal of Gastroenterology 2006年第4期12卷 615-620页

作者： ElenaGarcía-Martín JuanLMendoza CarlosTaxonera joséMLadero ManuelDíaz-Rubio CarmenMartínez joséAGAgúndez ElenaUrcelay EmilioGdelaConcha Department of Biochemistry & Molecular Biology & Genetics University of ExtremaduraBadajozSpain Service of Gastroenterology Hospital Clinico San CarlosComplutense UniversityMadridSpain Department of Pharmacology University of ExtremaduraBadajozSpain Service of Immunology Hospital Clinico San CarlosComplutense UniversityMadridSpain

AIM： To analyse the role of two common polymorphisms in genes coding for histamine metabolising enzymes as it relates to the risk to develop ulcerative colitis （UC） and the clinical course of these patients. METHODS： A cohort of 229 unrelated patients with UC recruited from a single centre and 261 healthy volunteers were analysed for the presence of Thr105Ile and His645Asp amino acid substitutions at histamine N-methyltransferase （HNMT） and diamine oxidase （ABP1） enzymes, respectively, by amplification-restriction procedures. All patients were phenotyped and followed up for at least 2 years （mean time 11 years）. RESULTS： There were no significant differences in the distribution of ABP1 alleles between ulcerative colitis patients and healthy individuals [OR （95% CI） for variant alleles = 1.22 （0.91-1.61）]. However, mutated ABP1 alleles were present with higher frequency among the 58 patients that required immunosuppresive drugs [OR （95 % CI） for carriers of mutated alleles 2.41 （1.21-4.83; P=0.006）], with a significant gene-dose effect （P= 0.0038）. In agreement with the predominant role of ABP1 versus HNMT on local histamine metabolism in human bowel, the frequencies for carriers of HNMT genotypes or mutated alleles were similar among patients,regardless clinical evolution, and control individuals. CONCLUSION： The His645Asp polymorphism of the histamine metabolising enzyme ABP1 is related to severity of ulcerative colitis.

关键词： Ulcerative colitis Pharmacogenetics Histamine N-Methyltransferase Diamine Oxidase

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