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Creating and moving nanoantenna cold spots anywhere

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Light(Science & Applications) 2022年第10期11卷 2335-2344页

作者： Alex j.Vernon francisco j.Rodriguez-Fortuno Department of Physics King's College LondonStrandLondon WC2R 2LSUnited Kingdom

Cold spots are sub-wavelength regions which might emerge near a nanoantenna,should one or more components of some far-field illumination cancel out with scattered *** show that by changing only the polarisation,amplitude,and phase of two plane waves,a unique,zero-magnitude and highly sub-wavelength cold spot can be created and moved anywhere in the space around a nanoantenna of any arbitrary *** can be achieved using ultra-fast modulated pulses,or a time-harmonic *** disturbed by a change in the nanoantenna's material or position,a manufactured cold spot is fragile and could be used in nanoscale *** technique exploits the linearity of Maxwell's equations and could be adapted to manipulate any phenomena governed by the linear wave equation,including acoustic *** is a means for potentially ultra-fast sub-wavelength electric field manipulation.

关键词： illumination scattered arbitrary

Nanoscale interactions between the nicotinic acetylcholine receptor and cholesterol

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BIOCELL 2021年第6期45卷 1479-1484页

作者： francisco j.BARRANTES Laboratory of Molecular Neurobiology Institute of Biomedical Research(BIOMED)UCA-CONICETFaculty of Medical SciencesBuenos AiresArgentina

Cholesterol is a maj.r lipid in biological *** not only plays a structural role but also modulates a wide range of functional properties of neurotransmitter and hormone receptors and ion *** membraneembedded segments of the paradigm neurotransmitter receptor for acetylcholine(nAChR)contain linear sequences of amino acids with the capacity to recognize *** cholesterol consensus domains have been designated as“CARC”and its mirror sequence“CRAC”.CARC preferentially occurs in the exoplasmic-facing membrane leaflet,and CRAC,in the cytoplasmic-facing *** motifs are highly conserved among ion-channel and neurotransmitter receptor proteins in vertebrate nervous systems,where they recognize cholesterol,and in prokaryotic homologues in bacteria,where they recognize *** phylogenetically conserved trait is an indication that the hopanoids in some bacteria and cholesterol in eukaryotes subserve analogous functions,probably contributing to the stability of membrane-embedded protein *** studies from our laboratory using superresolution optical microscopy(“nanoscopy”)have disclosed other interrelated functional and structural properties exerted by cholesterol on the *** neutral lipid content at the cell surface influences both the macromolecular organization of the receptor and its translational mobility(diffusion)in the plane of the membrane.

关键词： Cholesterol Pentameric ligand-gated ion channel Nicotinic acetylcholine receptor Membrane proteins Evolution Nanoscopy Cholesterol-recognition domains

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

Simulating FAS-induced apoptosis by using P systems

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Progress in Natural Science:Materials International 2007年第4期17卷 424-431页

作者： Smitha Cheruku Andrei Pǎun francisco j. Romero-Campero Mario j. Pérez-j.ménez Oscar H. Ibarra Department of Computer Science/IfM Louisiana Tech UniversityP.O. Box 10348RustonLA 71272USA Department of Computer Science and Artificial Intelligence University of SevilleAvda. Reina Mercedes s/n 41012SevillaSpain Department of Computer Science University of California-Santa BarbaraSanta BarbaraCA 93106USA

In contrast to differential equations, P systems are an unconventional model of computation which takes into consideration the discrete character of the quantity of components and the inherent randomness that exists in biological phenomena. The key feature of P systems is their compartmentalised structure which represents the heterogeneity of the structural organisation of the cells, and where one can take into account the role played by membranes in the functioning of the system, for example signalling at the cell surface, selective uptake of substances from the media, diffusion across different compartments, etc. We show here that P systems can be a reliable tool for Systems Biology and could even outperform in some cases the current simulation techniques based on differential equations. We will also use a strategy based on the well known Gillespie algorithm but running on more than one compartment called Multi-compartmental Gillespie Algorithm.

关键词： FAS-induced apoptosis P systems deterministic waiting times algorithm multi-compartmental Gillespie algorithm.

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 Alej.ndro 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

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How to express tumours using membrane systems

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Progress in Natural Science:Materials International 2007年第4期17卷 449-457页

作者： Miguel A. Gutiérrez-Naranj. Mario j. Pérez-j.ménez Agustín Riscos-Núez francisco j. Romero-Campero Department of Computer Science and Artificial Intelligence University of Seville Avda. Reina Mercedes s/n41012SevillaSpain

In this paper we discuss the potential usefulness of membrane systems as tools for modelling tumours. The approach is followed both from a macroscopic and a microscopic point of view. In the first case, one considers the tumour as a growing mass of cells, focusing on its external shape. In the second case, one descends to the microscopic level, studying molecular signalling pathways that are crucial to determine if a cell is cancerous or not. In each of these approaches we work with appropriate variants of membrane systems.

关键词： tumour membrane system modeling.

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

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Redox Regulation of Glycogen Biosynthesis in the Cyanobacterium Synechocystis sp. PCC 6803： Analysis of the AGP and Glycogen Synthases

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Molecular Plant 2014年第1期7卷 87-100页

作者： Sandra Diaz-Troya Luis Lopez-Maury Ana Maria Sanchez-Riego Miguel Roldan francisco j. Florencio Instituto de Bioquimica Vegetal y Fotosintesis Universidad de Sevilla-CSIC Americo Vespucio 49 E-41092 Sevilla Spain

Glycogen constitutes the maj.r carbon storage source in cyanobacteria, as starch in algae and higher plants. Glycogen and starch synthesis is linked to active photosynthesis and both of them are degraded to glucose in the dark to maintain cell metabolism. Control of glycogen biosynthesis in cyanobacteria could be mediated by the regulation of the enzymes involved in this process, ADP-glucose pyrophosphorylase （AGP） and glycogen synthase, which were identified as putative thioredoxin targets. We have analyzed whether both enzymes were subj.cted to redox modification using purified recombinant enzymes or cell extracts in the model cyanobacterium Synechocystis sp. PCC 6803. Our results indicate that both AGP and glycogen synthases are sensitive to copper oxidation. However, only AGP exhibits a decrease in its enzymatic activity, which is recovered after reduction by DTT or reduced thioredoxin （TrxA）, suggesting a redox control of AGP. In order to elucidate the role in redox control of the cysteine residues present on the AGP sequence （C45, C185, C320, and C337）, they were replaced with serine. All AGP mutant proteins remained active when expressed in Synechocystis, although they showed different electrophoretic mobility profiles after copper oxidation, reflecting a complex pattern of cysteines interaction.

关键词： cyanobacteria glycogen Synechocystis thioredoxin redox regulation.

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： j.an 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 subj.cted 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