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Influence of train speed and its mitigation measures in the short-and long-term performance of a ballastless transition zone

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Railway Engineering Science 2023年第4期31卷 309-324页

作者： Ana Ramos Rui Calçada antónio gomes.correia Department of Civil Engineering Faculty of EngineeringUniversity of PortoCONSTRUCT-LESEPortoPortugal Department of Civil Engineering University of MinhoISISEGuimarãesPortugal

The ballastless track is nowadays the most popular railway system due to the required low number of maintenance opera-tions and costs,despite the high *** gradual change from ballasted to ballastless tracks has been occurring in Asia,but also in Europe,increasing the number of transition *** transition zones are a special area of the railway networks where there is an accelerated process of track degradation,which is a major concern of the railway infrastructure ***,the accurate prediction of the short-and long-term performance of ballastless tracks in transition zones is an important topic in the current paradigm of building/rehabilitating high-speed *** work purposes the development of an advanced 3D model to study the global performance of a ballastless track in an embankment-tunnel transition zone considering the influence of the train speed(220,360,500,and 600 km/h).Moreover,a mitigation measure is also adopted to reduce the stress and displacements levels of the track in the transition.A resilient mat placed in the tunnel and embank-ment aims to soften the *** behaviour of the track with the resilient mat is evaluated considering the influence of the train speed,with special attention regarding the critical *** used methodology is a novel and hybrid approach that allows including short-term and long-term performance,through the development of a powerful 3D model combined with the implementation of a calibrated empirical permanent deformation model.

关键词： Ballastless track Train speed Numerical modelling Transition zone Critical speed

A geomechanics classification for the rating of railroad subgrade performance

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Railway Engineering Science 2022年第3期30卷 323-359页

作者： antonio gomes.correia Ana Ramos Department of Civil Engineering ISISEUniversity of MinhoGuimara˜esPortugal

The type of subgrade of a railroad foundation is vital to the overall performance of the track *** the train speed and tonnage increase,as well as environmental changes,the evaluation and influence of subgrade are even more paramount in the railroad track structure performance.A geomechanics classification for subgrade is proposed coupling the stiffness(resilient modulus)and permanent deformation behaviour evaluated by means of repeated triaxial loading *** classification covers from fine-to coarse-grained soils,grouped by UIC and *** this achievement,we first summarize the main models for estimating resilient modulus and permanent deformation,including the evaluation of their robustness and their sensitivity to mechanical and environmental *** is followed by the procedure required to arrive at the geomechanical classification and rating,as well as a discussion of the influence of environmental *** work is the first attempt to obtain a new geomechanical classification that can be a useful tool in the evaluation and modelling of the foundation of railway structures.

关键词： Subgrade Resilient modulus Permanent deformation Geomechanical classification

Cell-based therapeutic strategies for treatment of spinocerebellar ataxias:an update

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Neural Regeneration Research 2023年第6期18卷 1203-1212页

作者： Joana Sofia correia Sara Duarte-Silva antónio JoséSalgado Patrícia Maciel Life and Health Sciences Research Institute(ICVS) School of MedicineUniversity of MinhoBragaPortugal ICVS/3B’s–PT Government Associate Laboratory BragaGuimarãesPortugal

Spinocerebellar ataxias are heritable neurodegenerative diseases caused by a cytosine-adenine-guanine expansion,which encodes a long glutamine tract(polyglutamine)in the respective wild-type protein causing misfolding and protein *** features of polyglutamine spinocerebellar ataxias include neuronal aggregation,mitochondrial dysfunction,decreased proteasomal activity,and autophagy *** polyglutamine protein aggregates accumulate within neurons and cause neural dysfunction and death in specific regions of the central nervous *** ataxias are mostly characterized by progressive ataxia,speech and swallowing problems,loss of coordination and gait *** the past decade,efforts have been made to ameliorate disease symptoms in patients,yet no cure is *** studies have been proposing the use of stem cells as promising tools for central nervous system tissue *** far,pre-clinical trials have shown improvement in various models of neurodegenerative diseases following stem cell transplantation,including animal models of spinocerebellar ataxia types 1,2,and ***,contrasting results can be found in the literature,depending on the animal model,cell type,and route of administration ***,clinical trials using cellular implants into degenerated brain regions have already been applied,with the expectation that these cells would be able to differentiate into the specific neuronal subtypes and re-populate these regions,reconstructing the affected neural ***,the question of how feasible it is to continue such treatments remains unanswered,with long-lasting effects being still *** establish the value of these advanced therapeutic tools,it is important to predict the actions of the transplanted cells as well as to understand which cell type can induce the best outcomes for each *** studies are needed to determine the best route of administration,without neglec

关键词： cell transplantation engraftment induced pluripotent stem cells mesenchymal stem cells neural progenitor cells neuroprotection polyglutamine spinocerebellar ataxias secretome spinocerebellar ataxia stem cell therapy

Numerical simulation and analysis of water flow over stepped spillways

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Science China(Technological Sciences) 2009年第7期52卷 1958-1965页

作者： AMADOR antónio Hydraulic and Environmental Department Technologic School of Barreiro Barreiro 2830-144 Portugal

Numerical simulation of water flow over the stepped spillway is conducted using Mixture multiphase flow model. Different turbulence models are chosen to enclose the controlling equations. The turbulence models investigated are realizable k-ε model, SST k-ω model, v2-f model and LES model. The computational results by the four turbulence models are compared with experimental ones in the following aspects: mean velocity, the spanwise vorticity and the growth of the turbulent boundary layer thickness in the streamwise direction. It is found from the comparison that the realizable k-ε model, in which the rotation tensor is included, shows good performance for simulation of flows involving rotation, boundary layer and recirculation. The realizable k-ε model is the most efficient in simulating flow over stepped spillways. Further, the characteristics of water flow on the stepped spillway are studied in terms of the mean velocity profile normal to the pseudo-bottom and the pressure field on the steps based on the simulation results using realizable k-ε model.

关键词： stepped spillway turbulence model numerical simulation boundary layer

Combinatorial therapies for spinal cord injury: strategies to induce regeneration

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Neural Regeneration Research 2019年第1期14卷 69-71页

作者： Eduardo D.gomes Nuno A.Silva antónio J. Salgado Life and Health Sciences Research Institute (ICVS) School of Medicine University of Minho Campus de Gualtar ICVS/3B’s–PT Government Associate Laboratory

Spinal cord injury(SCI)is a condition without treatment,mainly characterized by the loss of motor and sensory function below the level of *** is accompanied by several complications such as cardiac and respiratory compromise,and often patients present psychological ailments associated with the drastic alteration of their normal *** pathophysiology derives from a massive damage to the spinal cord tissue,which is propagated

关键词：损害绳索新生治疗感觉功能生活方式星形细胞并发症

Conflicts in passive building performance:Retrofit and regulation of informal neighbourhoods

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Frontiers of Architectural Research 2021年第3期10卷 625-638页

作者： Gonçalo Araújo Inês Pereira antónio Leitão Manuel correia Guedes INESC-ID/Instituto Superior Tećcnico University of LisbonLisbonPortugal Instituto Superior Tećcnico University of LisbonLisbonPortugal

Urbanization growth in developing countries raises concerns regarding these countries’ability to consider slums,underdeveloped communities,and neighbourhoods in economic,health,and climatic *** research proposes a methodology that integrates algorithmic design and analysis strategies to define,study,and measure key parameters that affect the rehabilitation of these *** scenarios and design dimensions are analysed to establish design and comfort thresholds,and alternatives are simulated and tested to identify possible *** methodology includes an optimisation step integrated in the workflow that maximizes thermal comfort,minimizes costs,and ensures fairness in the rehabilitation of large sets of *** step identifies improvements in thermal comfort for different construction scenarios from which a two-staged rehabilitation plan is *** first stage comprises a sensitivity analysis to identify building materials regarding their improvement and cost of application,and the second defines the most suitable construction scenarios considering the results from the optimisation process for each ***,we research and document guidelines regarding the parameters tested for building design,revealing the existing conflicts between performance objectives,and the architect’s role in their prioritization.

关键词： Urban regeneration Informal housing Algorithmic design Optimisation Simulation

Calculations of Optical Rotation from Density Functional Theory

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Chinese Physics Letters 2007年第5期24卷 1207-1209页

作者： antǒnio Canal Neto Francisco Elias Jorge Departamento de Fisica Universidade Federal do Espírito Santo 29060-900 Vitória ES Brazil

Density function theory calculations of frequency-dependent optical rotations [α]ω for three rigid chiral molecules are reported. Calculations have been carried out at the sodium D line frequency, using the ADZP basis set and a wide variety of functionals. Gauge-invariant atomic orbitals are used to guarantee origin-independent values of [ω]D. In addition, study of geometry dependence of [ω]D is reported. Using the geometries optimized at the B3LYP/ADZP level, the mean absolute deviation of B3LYP/ADZP and experimental laiD values yields 60.1°/（dm g/cm^3）. According to our knowledge, this value has not been achieved until now with any other model.

关键词： MOLECULAR WAVE-FUNCTIONS BASIS-SETS MP2 HF

MicroRNAs and cancer drug resistance: over two thousand characters in search of a role

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Cancer Drug Resistance 2019年第3期2卷 618-633页

作者： Bruno Costa gomes Jose Rueff antónio Sebastião Rodrigues Centre for Toxicogenomics and Human Health GeneticsOncology and Human ToxicologyNOVA Medical SchoolUniversidade Nova de LisboaLisboa 1150-008Portugal

MicroRNAs(miRNAs),a group of small regulatory noncoding RNAs,transformed our thinking on gene *** than two thousand human miRNAs have been identified thus *** bind imperfectly to the 3’-untranslated region of target mRNA and have been involved in several pathological conditions including *** fact,major hallmarks of cancer,such as the cell cycle,cell proliferation,survival and invasion are modulated by *** drug resistance(CDR)has also been described as being modulated by *** remains a burden for cancer therapy and patients’outcome,often resulting in more aggressive tumours that tend to metastasize to distant *** this review we discuss the role of miRNAs influencing drug metabolism and drug influx/efflux,two important mechanisms of CDR.

关键词： MicroRNAs gene regulation cancer drug resistance drug transporters drug metabolism

Generalized Hardy Spaces

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Acta Mathematica Sinica,English Series 2010年第9期26卷 1673-1692页

作者： Alexandre ALMEIDA antónio M.CAETANO Departamento de Matemática Universidade de Aveiro

Hardy spaces with generalized parameter are introduced following the maximal characterization approach. As particular cases, they include the classical Hp spaces and the Hardy-Lorentz spaces H^p,q. Real interpolation results with function parameter are obtained, Based on them, the behavior of some classical operators is studied in this generalized setting.

关键词： Generalized Hardy spaces maximal functions Poisson kernel interpolation with function parameter Riesz potentials singular integrals