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A coupled fluid FEm-DEm technique for predicting blasting operations in tunnels

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Underground Space 2018年第4期3卷 310-316页

作者： francisco Zarate Jose m.gonzalez Juan miquel Rainald Lohner Eugenio Onate Centre Internacional de metodes Numerics en Enginyeria(CImNE) Spain Universitat Politecnica de Catalunya(UPC) Gran Capitan s/nCampus Nord08034 BarcelonaSpain George mason University USA1

We present recent developments in the coupling of the finite element method(FEm)and the discrete element method(DEm)for the analysis of rock blasting operations in *** coupled FEm-DEm technique has been proven to be an efficient procedure for pre-dicting the multiple fractures of rock induced by the loads generated in *** coupled FEm-DEm procedure is applied in tunnel construction,as well as to gas pressure blasting pyrotechnics to break rocks for the excavation of the tunnel *** the latter case,the effect of gas explosion is modeled by solving the equations of gas dynamics in the analysis domain using *** effect of gas forces in the underlying rock mass is modeled via an embedded fluid-structure interaction *** efficiency of the coupled FEm-DEm tech-nique is demonstrated in several examples of fracture tests and rock blasting problems related to tunnel *** examples pre-sented indicate that the combination of the DEm with simple three-node linear triangular elements(for two-dimensional problems)captures the onset of fractures and their evolution accurately,accounting for the penetration of gas in the failure domain(Zarate&Onate,2015;Zarate,Cornejo,&Onate,2018).

关键词： Discrete elements Finite elements Fracture mechanics FEm-DEm Gas dynamics

Amyloid-beta pathology-induced nanoscale synaptic disruption:the case of the GABA_B-GIRK assembly

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Neural Regeneration Research 2025年第5期20卷 1409-1410页

作者： Rafael Lujan Alejandro martín-Belmonte Sergi Ferré francisco Ciruela Synaptic Structure Laboratory Instituto de Biomedicina de la UCLM(IB-UCLM)Departamento de Ciencias MédicasInstituto de Investigación en Salud de Castilla-La Mancha(IDISCAM)Facultad de MedicinaUniversidad Castilla-La ManchaCampus BiosanitarioC/AlmansaAlbaceteSpain Integrative Neurobiology Section National Institute on Drug AbuseIntramural Research ProgramNational Institutes of HealthBaltimoreMDUSA Pharmacology Unit Department of Pathology and Experimental TherapeuticsSchool of Medicine and Health SciencesInstitute of NeurosciencesUniversity of BarcelonaNeuropharmacology&Pain GroupNeuroscience ProgramBellvitge Institute for Biomedical ResearchL’Hospitalet de LlobregatSpain

Alzheimer's disease (AD) is characterized by an imbalance between excitatory and inhibitory brain networks,leading to aberrant homeostatic synaptic *** has progressively been recognized as syna ptopathy and syna ptic dysfunction has been identified as a key component of its pathogenesis (Schirinzi et al.,2020).Syna ptic dysfunction is believed to precede synapse loss,a primary biological correlate of cognitive decline in AD,inevita bly associated with neuronal death.

关键词： Alzheimer pathology

SPLITTING SCHEmES FOR A NAVIER-STOKES-CAHN-HILLIARD mODEL FOR TWO FLUIDS WITH DIFFERENT DENSITIES

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Journal of Computational mathematics 2014年第6期32卷 643-664页

作者： francisco Guillen-gonzalez Giordano Tierra Departamento de Ecuaciones Diferenciales y Andlisis Numgrico and ImUS Universidad de Sevilla 41012 Seville Spain Department of Applied and Computational mathematics and Statistics University of Notre Dame Notre Dame IN 46556 USA

In this work, we focus on designing efficient numerical schemes to approximate a ther- modynamically consistent Navier-Stokes/Cahn-Hilliard problem given in [3] modeling the mixture of two incompressible fluids with different densities. The model is based on a diffuse-interface phase-field approach that is able to describe topological transitions like droplet coalescense or droplet break-up in a natural way. We present a splitting scheme, decoupling computations of the Navier-Stokes part from the Cahn-Hilliard one, which is unconditionally energy-stable up to the choice of the potential approximation. Some nu- merical experiments are carried out to validate the correctness and the accuracy of the scheme, and to study the sensitivity of the scheme with respect to different physical pa- rameters.

关键词： Two-phase flow Diffuse-interface phase-field Cahn-Hilliard Navier-Stokes,Energy stability Variable density mixed finite element Splitting scheme.

Indirect determination of shear wave velocity in slow formations using full-wave sonic logging technique

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Journal of Rock mechanics and Geotechnical Engineering 2020年第6期12卷 1226-1233页

作者： francisco Beltran Alvaro Yañez-gonzalez maría J.Crespo Belgar Engineering Consultants Gabriel García Márquez 9Collado-Villalba28400Spain ESTEYCO Menéndez Pidal 17Madrid28036Spain Principia Engineering Consuxltants Velázquez 94Madrid28006Spain

This article presents a case study concerning a seismic characterization ***-wave sonic logging was used to characterize the shallow compressional wave and shear wave velocity profiles in the *** values of the Poisson’s ratio derived from the velocity profiles suggested that the boreholes might have traversed slow formations(*** shear wave velocity smaller than the borehole fluid compressional wave velocity or“mud-wave speed”)and that conventional processing of the sonic logs might have misinterpreted the direct arrivals of fluid acoustic waves as arrivals caused by shear wave propagation in the ***,the shear wave velocity profiles provided by the contractor were considered to be unreliable by the project *** address these problems,a non-conventional determination of the shear wave velocity was implemented,based on the relationship between the Poisson’s ratio of the rock formation and the shape of the first train of sonic waves which arrived to the receivers in the sonic *** relationship was determined based on several hundreds of finite element simulations of the acoustic wave propagation in boreholes with the same diameter as used in the *** present article describes how this non-conventional approach was developed and implemented to obtain the shear wave velocity profiles from the raw sonic *** approach allows an extension of the range of applicability of full-wave sonic logging to determination of shear wave velocity profiles in formations with low compressional wave *** method could be used to obtain shear wave velocity profiles where compressional wave velocity is as low as slightly larger than the mud-wave speed.A sample sonic log in Log ASCII Standard(LAS)format is provided as supplementary material to this paper via mendeley Data,together with the FORTRAN source code used to process the log following the approach described in this study.

关键词： Sonic logging Slow formation Shear wave velocity Poisson’s ratio P-wave packet

multi-objective optimization design of bridge piers with hybrid heuristic algorithms

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第6期13卷 420-432页

作者： francisco J. mARTINEZ-mARTIN Fernando gonzalez-VIDOSA Antonio HOSPITALER Víctor YEPES Department of Geotechnical Engineering Universitat Politècnica de València 46022 Valencia Spain Department of Construction Engineering ICITECH Universitat Politècnica de València 46022 Valencia Spain

This paper describes one approach to the design of reinforced concrete (RC) bridge piers, using a three-hybrid multi- objective simulated annealing (SA) algorithm with a neighborhood move based on the mutation operator from the genetic algorithms (GAs), namely mOSAmO1, mOSAmO2 and mOSAmO3. The procedure is applied to three objective functions: the economic cost, the reinforcing steel congestion and the embedded CO 2 emissions. Additional results for a random walk and a descent local search multi-objective algorithm are presented. The evaluation of solutions follows the Spanish Code for structural concrete. The methodology was applied to a typical bridge pier of 23.97 m in height. This example involved 110 design variables. Results indicate that algorithm mOSAmO2 outperforms other algorithms regarding the definition of Pareto fronts. Further, the proposed procedure will help structural engineers to enhance their bridge pier designs.

关键词： Bridge piers Concrete structures multi-objective optimization Simulated annealing (SA) Structural design

Hydrogen sulfide:A novel component in Arabidopsis peroxisomes which triggers catalase inhibition

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Journal of Integrative Plant Biology 2019年第7期61卷 871-883页

作者： francisco J.Corpas Juan B.Barroso Salvador gonzalez-Gordo maria A.munoz-Vargas Jose m.Palma Group of Antioxidants Free Radicals and Nitric Oxide in BiotechnologyFood and AgricultureDepartment of BiochemistryCell and Molecular Biology of PlantsEstacion Experimental del ZaidfnCSICC/Profesor Albareda 1E-18008 GranadaSpain Group of Biochemistry and Cell Signaling in Nitric oxide Department of Biochemistry and Molecular BiologyCampus"Las Lagunillas"E-23071University of JaenJaenSpain

Plant peroxisomes have the capacity to gen erate different reactive oxygen and nitrogen species(ROS and RNS),such as H2O2,superoxide radical(O2^·-),nitric oxide and peroxynitrite(ONOO^-).These organelles have an active nitrooxidative metabolism which can be exacerbated by adverse stress *** sulfide(H2S)is a new signaling gasotransmitter which can mediate the posttranslational modification(PTm)*** used Arabidopsis thaliana transgenic seedlings expressing cyan fluorescent protein(CFP)fused to a canonical peroxisome targeting signal 1(PTS1)to visualize peroxisomes in living cells,as well as a specific fluorescent probe which showed that peroxisomes contain H2S.H2S was also detected in chloroplasts under glyphosate-induced oxidative stress *** enzyme activities,including catalase,photorespiratory H2O2-generating glycolate oxidase(GOX)and hydroxypyruvate reductase(HPR),were assayed in vitro with a H2S *** line with the persulfidation of this enzyme,catalase activity declined significantly in the presence of the H2S *** corroborate the inhibitory effect of H2S on catalase activity,we also assayed pure catalase from bovine liver and pepper fruit-enriched samples,in which catalase activity was *** together,these data provide evidenee of the presence of H2S in plant peroxisomes which appears to regulate catalase activity and,consequently,the peroxisomal H2O2 metabolism.

关键词： Hydrogen sulfide triggers catalase inhibition

Shear velocity criterion for incipient motion of sediment

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Water Science and Engineering 2014年第2期7卷 183-193页

作者： francisco J.m.SImOES U.S. Geological Survey Geomorphology and Sediment Transport LaboratoryGolden CO 80403 USA

The prediction of incipient motion has had great importance to the theory of sediment transport. The most commonly used methods are based on the concept of critical shear stress and employ an approach similar, or identical, to the Shields diagram. An alternative method that uses the movability number, defined as the ratio of the shear velocity to the particle＇s settling velocity, was employed in this study. A large amount of experimental data were used to develop an empirical incipient motion criterion based on the movability number. It is shown that this approach can provide a simple and accurate method of computing the threshold condition for sediment motion.

关键词： incipient motion sediment transport Shields diagram critical shear stress criticalshear velocity movability number

Dipole (hyper)polarizabilities of neutral silver clusters

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Chinese Physics B 2016年第12期25卷 217-222页

作者： francisco E Jorge Luiz G m de macedo Departarnento de Fisica Universidade Fedoral do Espirito Santo 29060-900 Vitoria Brazil Unidade Academica de Fisica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Faculdade de Biotecnologia ICB Universidade Federal do Para 66075-110 Belem Brazil

At the Douglas-Kroll-Hess （DKI4） level, the B3PW91 functional along with the all-eleclron relativistic basis sets of valence triple and quadruple zeta qualities are used to determine the structure, stability, and electronic properties of the small silver clusters （Agn, n ≤ 7）. The results presented in this study are in good agreement with the experimental data and theoretical values obtained at a higher level of theory from the literature. Static polarizability and hyperpolarizability are also reported. It is verified that the mean dipole polarizability per atom exhibits an odd-even oscillation and that the polarizability anisotropy is directly related to the cluster shape. In this article, the first study of hyperpolarizabilities of small silver clusters is presented. Except for the monomer, the second hyperpolarizabilities of the silver clusters are significantly larger than those of the copper clusters.

关键词： B3PW91 functional all-electron basis sets non-relativistic and DKH2 calculations silver clusters,dipole (hyper)polarizabilities

Stability analysis of slopes with planar failure using variational calculus and numerical methods

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Frontiers of Structural and Civil Engineering 2020年第5期14卷 1262-1273页

作者： Norly BELANDRIA RobertoÚCAR francisco m.LEON Ferri HASSANI Geological Engineering School University of Los AndesMérida 5101Venezuela mechanical Engineering School University of Los AndesMérida 5101Venezuela Department of mining and material Engineering McGill UniversityMontrealQC H3A 0E9Canada

This study investigates the technique of variational calculus applied to estimate the slope stability considering the mechanism of planar *** critical plane failure surface should be determined because it theoretically indicates the most unfavorable plane to be considered when stabilizing a slope to rectify the instability generated by several statistically possible *** generates integrals that can be solved by numerical methods,such as the Newton Cotes and the finite differences ***,a system of nonlinear equations is obtained and *** surface of the critical planar failure is determined by applying the condition of transversality in mobile boundaries,for which various examples are *** number of slices is varied in one of the examples,while the surface of the critical planar failure is determined in the *** are compared using analytical methods through axis *** the results obtained by considering normal stress,safety factors,and critical planar failure are nearly the same;however,in this research,a study is carried out for“n”number of slices using programming ***-routines are important because they can be applied in slopes with different geometry,surcharge,interstitial pressure,and pseudo-static load.

关键词： slopes stability planar failure variational calculus numerical methods