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Diffusion dynamics and characterization of attogram masses in optically trapped single nanoparticles using laser-induced plasma imaging

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Nano Research 2023年第5期16卷 7470-7480页

作者： Pablo Purohit francisco j.Fortes j.vier Laserna UMALASERLAB Departamento de Química AnalíticaUniversidad de MálagaC/Jiménez Fraud 4Malaga 29010Spain Niels Bohr Institute University of CopenhagenBlegdamsvej 172100 CopenhagenDenmark

In the present work,a wavelength-selected plasma imaging analysis system is presented and used to track photons emitted from single-trapped nanoparticles in air at atmospheric *** isolated nanoentities were atomized and excited into plasma state using single nanosecond laser *** use of appropriate wavelength filters alongside time-optimized acquisition settings enabled the detection of molecular and atomic emissions in the *** photon detection efficiency of the imaging line resulted in a signal>400 times larger than the simultaneously-acquired dispersive spectroscopy *** increase in sensitivity outlined the evolution of diverse physicochemical processes at the single particle scale which included heat and momentum transfer from the plasma into the particle as wells as chemical *** imaging detection of excited fragments evidenced different diffusion kinetics and time frames for atoms and molecules and their influence upon both the spectroscopic emission readout and fabrication processes using the plasma as a ***,the origin of molecular species,whether naturally-occurring or derived from a chemical reaction in the plasma,could also be studied on the basis of compositional gradients found on the *** of detection for the inspected species ranged from tens to hundreds attograms,thus leading to an exceptional sensing principle for single nanoentities that may impact several areas of science and technology.

关键词： single nanoparticle inspection wavelength-selected laser-induced plasma imaging laser fabrication attogram characterization atomic/molecular diffusion

Real Renormings on Complex Banach Spaces

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Chinese Annals of Mathematics,Series B 2008年第3期29卷 239-246页

作者： francisco j GARC■A-PACHECO Alejandro MIRALLES Department of Mathematical Sciences Kent State University Departamento de Análisis Matemático Universidad de Valencia

The authors prove that every complex Banach space admits an equivalent real norm that is far away from being a complex norm. Furthermore, this real norm can be chosen to share many properties with complex norms, but i... 详细信息

关键词： Complex norms Real norms Hilbert space

A SHORT NOTE ABOUT EXPOSED POINTS IN REAL BANACH SPACES

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Acta Mathematica Scientia 2008年第4期28卷 797-800页

作者： Antonio Aizpuru francisco j Garcia-Pacheco Departamento de Matemá ticas Universidad de Cá diz Department of Mathematical Sciences Kent State University

We express the set of exposed points in terms of rotund points and non-smooth *** long as we have Banach spaces each time＂bigger＂,we consider sets of non-smooth points each time＂smaller＂.

关键词： Exposed point exposed face rotund point smooth point

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

Fully integrated and broadband Si-rich silicon nitride wavelength converter based on Bragg scattering intermodal four-wave mixing

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Photonics Research 2024年第3期12卷 I0001-I0010页

作者： VALERIO VITALI THALÍA DOMÍNGUEZ BUCIO HAO LIU jOSÉMANUEL LUQUE GONZÁLEZ francisco jURADO-ROMERO ALEjANDRO ORTEGA-MOÑUX GLENN CHURCHILL jAMES C.GATES jAMES HILLIER NIKOLAOS KALFAGIANNIS DANIELE MELATI jENS H.SCHMID ILARIA CRISTIANI PAVEL CHEBEN j.GONZALO WANGÜEMERT-PÉREZ ÑIGO MOLINA-FERNÁNDEZ FREDERIC GARDES COSIMO LACAVA PERIKLIS PETROPOULOS Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK Electrical Computer and Biomedical Engineering DepartmentUniversity of PaviaPavia 27100Italy Telecommunication Research Institute(TELMA) Universidad de MálagaCEI Andalucı´a TECHE.T.S.I.Telecomunicación29010 MálagaSpain School of Science and Technology Nottingham Trent UniversityNottingham NG118NSUK Department of Electrical Engineering Eindhoven University of TechnologyEindhoven 5600 MBThe Netherlands Department of Materials Science and Engineering University of IoanninaIoannina 45110Greece Centre de Nanosciences et de Nanotechnologies UniversitéParis-SaclayCNRS91120 PalaiseauFrance Advanced Electronics and Photonics Research Center National Research Council CanadaOttawaOntario K1A 0R6Canada

Intermodal four-wave mixing(FWM)processes have recently attracted significant interest for all-optical signal processing applications thanks to the possibility to control the propagation properties of waves exciting distinct spatial modes of the same *** allows,in principle,to place signals in different spectral regions and satisfy the phase matching condition over considerably larger bandwidths compared to intramodal ***,the demonstrations reported so far have shown a limited bandwidth and suffered from the lack of on-chip components designed for broadband manipulation of different *** demonstrate here a silicon-rich silicon nitride wavelength converter based on Bragg scattering intermodal FWM,which integrates mode conversion,multiplexing and de-multiplexing functionalities *** system enables wavelength conversion between pump waves and a signal located in different telecommunication bands(separated by 60 nm)with a 3 dB bandwidth exceeding 70 nm,which represents,to our knowledge,the widest bandwidth ever achieved in an intermodal FWM-based system.

关键词： scattering pump modal

Dopaminergic-cholinergic imbalance in movement disorders: a role for the novel striatal dopamine D2-muscarinic acetylcholine M1 receptor heteromer

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Neural Regeneration Research 2021年第7期16卷 1406-1408页

作者： RenéA.j.Crans francisco Ciruela Laboratory of Toxicology Department of BioanalysisGhent UniversityGhentBelgium Unitat de Farmacologia Departament Patologia i Terapèutica ExperimentalFacultat de Medicina i Ciències de la SalutIDIBELLUniversitat de BarcelonaL’Hospitalet de LlobregatBarcelonaSpain Institut de Neurociències Universitat de BarcelonaBarcelonaSpain

The striatum is the primary input structure of the basal ganglia, which participates in motivational and goaldirected behaviors(Pisani et al., 2007).In physiological conditions, local cholinergic interneurons(ChIs) an... 详细信息

关键词： al. Dopamine dopamine

GraphFlow+:Exploiting Conversation Flow in Conversational Machine Comprehension with Graph Neural Networks

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Machine Intelligence Research 2024年第2期21卷 272-282页

作者： jing Hu Lingfei Wu Yu Chen Po Hu Mohammed j.Zaki School of Computer Science Central China Normal UniversityWuhan 430079China Pinterest San Francisco 94016USA Meta Mountain View 94039USA Rensselaer Polytechnic Institute Troy 12180USA

The conversation machine comprehension(MC)task aims to answer questions in the multi-turn conversation for a single ***,recent approaches don’t exploit information from historical conversations effectively,which results in some references and ellipsis in the current question cannot be *** addition,these methods do not consider the rich semantic relationships between words when reasoning about the passage *** this paper,we propose a novel model GraphFlow+,which constructs a context graph for each conversation turn and uses a unique recurrent graph neural network(GNN)to model the temporal dependencies between the context graphs of each ***,we exploit three different ways to construct text graphs,including the dynamic graph,static graph,and hybrid graph that combines the *** experiments on CoQA,QuAC and DoQA show that the GraphFlow+model can outperform the state-of-the-art approaches.

关键词： Conversational machine comprehension(MC) reading comprehension question answering graph neural networks(GNNs) natural language processing(NLP)

Bone Remodeling and Energy Metabolism:New Perspectives

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Bone Research 2013年第1期1卷 72-84页

作者： francisco j.A.de Paula Clifford j.Rosen Department of Internal Medicine School of Medicine of Ribeiro PretoUniversity of So PauloBrazil Center for Clinical and Translational Research Maine Medical Center Research InstituteUSA

Bone mineral, adipose tissue and energy metabolism are interconnected by a complex and multilevel series of networks. Calcium and phosphorus are utilized for insulin secretion and synthesis of high energy compounds. Adipose tissue store lipids and cholecalciferol, which, in turn, can influence calcium balance and energy expenditure. Hormones long-thought to solely modulate energy and mineral homeostasis may influence adipocytic function. Osteoblasts are a target of insulin action in bone. Moreover, endocrine mediators, such as osteocalcin, are synthesized in the skeleton but regulate carbohydrate disposal and insulin secretion. Finally, osteoblasts and adipocytes originate from the same mesenchymal progenitor. The mutual crosstalk between osteoblasts and adipocytes within the bone marrow microenvironment plays a crucial role in bone remodeling. In the present review we provide an overview of the reciprocal control between bone and energy metabolism and its clinical implications.

关键词： bone adipose tissue mineral metabolism energy metabolism leptin osteocalcin

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