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Retrieval of Elastic Green’s Tensor near a Cylindrical Inhomogeneity from Vector Correlations

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Communications in Computational Physics 2008年第1期3卷 250-270页

作者： Juan AP´erez-Ruiz francisco Luzon francisco J.Sanchez-Sesma Grupo de Geof´ısica Aplicada Departamento de F´ısica AplicadaUniversidad de Almer´ıaCa˜nada de San Urbano s/n04120-Almer´ıaSpain Departamento de Sismolog´ıa Instituto de IngenieriaUniversidad Nacional Aut´onoma de M´exicoCd.UniversitariaCircuito Escolar s/nCoyoac´an 04510M´exico D.F.Mexico.

Multiple scattering of elastic waves in realistic media makes that averagefield intensities or energy densities follow diffusive processes. In such regime the successiveP to S energy conversions by distributed random inhomogeneities give rise toequipartition which means that in the phase space the available elastic energy is distributedin averagewith equal amounts among the possible states of P and S waves. Insuch diffusive regime the P to S energy ratio equilibrates in an universal way independentof the particular details of the scattering. It has been demonstrated that averagingthe cross correlations at any two points of an elastic medium subjected to diffuse elasticwavefields leads to the emergence of the Green function, which is the wave fieldthat would be observed at one position if an impulsive load is applied at the other. Inthis work we study the problem of the retrieval of the 2D tensor elastodynamic Greenfunction in an infinite elastic space containing a circular cylinder inclusion. We illuminateisotropically the elastic spacewith plane waves. We assume the spectra for both Pand S waves uniform but such that the energy ratio ES/EP=(a/b)2, which is the onepredicted by equipartition theory in two-dimensions. We then show that the Fouriertransform of azimuthal average of the cross-correlation of motion between two pointswithin an elastic medium is proportional to the imaginary part of the exact Green tensorfunction between these points. The numerical results presented here point out thepossibility of detection and imaging of diffractors and resonant diffractors by crosscorrelation even in presence of attenuation exists.

关键词： Multiple scattering elastic waves elastic Green’s tensor

Endoscopic submucosal dissection for early gastric cancer:A major challenge for the west

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 1965-1968页

作者： francisco Schlottmann Department of Surgery University of Illinois at ChicagoChicagoIL 60612United States Department of Surgery Hospital Alemán of Buenos AiresBuenos Aires 1640-C1118AATArgentina

Gastric cancer(GC)is the 5th most common cancer and the 3rd most common cause of cancer mortality *** main endoscopic resective techniques exist for early GC(EGC):Endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD).ESD has been widely embraced in the last decade because it allows radical en bloc resections and is associated with better outcomes,as compared to ***,the lack of training opportunities and flat learning curve due to low volume of EGC cases represent major obstacles to obtain proficiency on ESD in the *** this procedure is highly efficient for the treatment of EGC,dedicated training programs with a stepwise approach and updated guidelines for ESD embracement are needed in Western countries.

关键词： Gastric cancer Early gastric cancer Endoscopy West Training

Clues from a missense mutation of the adenosine A1 receptor gene associated with early-onset Parkinson’s disease

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Neural Regeneration Research 2023年第10期18卷 2204-2205页

作者： Sergi Ferré Leonardo Pardo francisco Ciruela Integrative Neurobiology Section National Institute on Drug AbuseIntramural Research ProgramNational Institutes of HealthBaltimoreMDUSA Laboratory of Computational Medicine Biostatistics UnitFaculty of MedicineUniversitat Autònoma BarcelonaBellaterraBarcelonaSpain Pharmacology Unit Department of Pathology and Experimental TherapeuticsSchool of Medicine and Health SciencesInstitute of NeurosciencesUniversity of Barcelona.Neuropharmacology&Pain GroupNeuroscience ProgramBellvitge Institute for Biomedical ResearchL’Hospitalet de LlobregatSpain

Parkinson’s disease (P D) is a com plex neu rodegenerative disorder for which ra re and common genetic variants contribute to disease risk,onset,and *** genetic contribution to PD can be classified mainly in,first,rare DNA variants that are highly penetrant and therefore causal,which are typically associated with monogenic PD;and second,more common risk polymorphic variants,which individually exert a small increase in the risk of the disease,which are usually identified in the most prevalent and apparently sporadic PD (Blauwendraat et al.,2020).

关键词： typically degenerative

A beta regression analysis of COVID-19 mortality in Brazil

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Infectious Disease Modelling 2023年第2期8卷 309-317页

作者： francisco Cribari-Neto Department of Statistics Federal University of PernambucoRecifePE50670-901Brazil

Brazil was one of the countries most impacted by the COVID-19 pandemic,with a cumulative total of nearly 700,000 deaths by early *** country's federative units were unevenly affected by the pandemic and adopted mitigation measures of different scopes and *** was intense conflict between the federal government and state governments over the relevance and extent of such *** build a simple regression model with good predictive power on state COVID-19 mortality rates in *** results reveal that the federative units'urbanization rate and per capita income are important for determining their mean mortality rate and that the number of physicians per 100,000 inhabitants is important for modeling the mortality rate *** on the fitted model,we obtain approximations for the levels of administrative efficiency of local governments in dealing with the pandemic.

关键词： Beta regression Coronavirus COVID-19 Pandemic Regression analysis

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

Influence of the Iron Anisothermal Sintering on the Characteristic of the Hollow Cathode Discharge

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材料热处理学报 2004年第5期25卷 83-87页

作者： BRUNATTO Silvio francisco MUZART Joel Louis Rene Department of Mechanical Engineering UFPR 81531-990 Curitiba-PR BrazilDepartment of Mechanical Engineering UFSC 88040-900 Florianopolis-SC Brazil

This work studies the influence of anisothermal iron sintering process on hollow cathode discharge characteristics. Two independent cathodes form an annular discharge. The pressed cylindrical iron powder sample, acting as central cathode, was placed concentrically in the interior of an external cathode. The external cathode, machined from an AISI 310 steel bar, besides acting to confine the geometry of the plasma, can also acts as a source of alloying elements. The sample heating is a function of the ion bombardment energy and, so, of the discharge electrical parameters: current (or current density) and the effective potential applied to the cathode. Successive anisothermal sintering is performed in a same sample until the reproducibility of the electrical parameters being obtained. The heating experiments up to 1250 °C, in a gas mixture of 80% Ar + 20% H2, at pressure of 133 Pa, at flow of 2xlO"6 mV, with an inter-cathode radial space of 5.8 mm, were carried out. It was verified the metallurgical evolution of the iron sample sintering process influences the current-?0n (time switched-on of the pulse) characteristics of the discharge.

关键词：空心阴极放电等离子体焊结烧结铁溅射非等温焙烧

Hybrid flexural components： Testing pre-stressed steel and GIFRP bars together as reinforcement for flexural members

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Frontiers of Structural and Civil Engineering 2018年第3期12卷 352-360页

作者： Mohammed FARUQI Oved I. MATA francisco AGUINIGA Department of Civil and Architectural Engineering Texas A&M University Kingsville TX 77843 USA

Concrete members historically have used either pre-stressed steel or steel bars. In recent years there has been an increased interest in the use of fiber reinforced polymer （FRP） materials. However, the flexure behavior of a hybrid system reinforced by the combination of pre-stressed steel and glass fiber reinforced （GFRP） is still relatively unknown. The purpose of this work is to study this. Two slabs of 100 and 150-millimeter thickness, with a span of 2.1 m reinforced with both pre-stressing steel and GFRP were constructed and tested to failure using ACI 318-11 and ACI 440.1 R-15. The concrete had strength of 31 MPa and the slabs were respectively reinforced with 5#4 bars and 3#5 bars. Each slab had 37.41 mm2 prestressing wire with a failure stress of 1722.5 MPa. The experimental flexural strength and deflection of slabs were compared with their respective sizes theoretical slabs. The theoretical slabs were either reinforced with pre-stressed steel or GFRP rebars, or a hybrid system. It was found that the hybrid system produces better results.

关键词： Partial pre-stressing composite structures GFRP bars

Generating native user interfaces for multiple devices by means of model transformation

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Frontiers of Information Technology & Electronic Engineering 2015年第12期16卷 995-1017页

作者： Ignacio MARIN francisco ORTIN German PEDROSA Javier RODRIGUEZ Department of Research and Development CTIC Foundation Department of Computer Science University of Oviedo

In the last years, the types of devices used to access information systems have notably increased using different operating systems, screen sizes, interaction mechanisms, and software features. This device fragmentation is an important issue to tackle when developing native mobile service front-end applications. To address this issue,we propose the generation of native user interfaces(UIs) by means of model transformations, following the modelbased user interface(MBUI) paradigm. The resulting MBUI framework, called LIZARD, generates applications for multiple target platforms. LIZARD allows the definition of applications at a high level of abstraction, and applies model transformations to generate the target native UI considering the specific features of target platforms. The generated applications follow the UI design guidelines and the architectural and design patterns specified by the corresponding operating system manufacturer. The objective is not to generate generic applications following the lowest-common-denominator approach, but to follow the particular guidelines specified for each target device. We present an example application modeled in LIZARD, generating different UIs for Windows Phone and two types of Android devices(smartphones and tablets).

关键词： Model-to-model transformation Native user interfaces Model-based user interfaces Model-driven engineering

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