Search results for "JUNCTION"

showing 10 items of 862 documents

Low Levels of Acetylcholine Receptor Delta-Subunit Message and Protein in Human Thymus Suggests the Occurrence of ‘Triplet Receptors’ in Thymic Myoid…

2000

Myasthenia gravis (MG) is an autoimmune disease caused by autoantibodies against the acetylcholine receptor (AChR) at the neuromuscular junction [1]. The muscular AChR has been extensively characterized [2], but whether the muscular AChR plays a role during the initiation of MG is unknown [3]. The muscular AChR is a pentameric ion channel composed of 4 different subunits [2, 4]. The fetal AChR expressed during intrauterine life and after denervation of adult muscle exhibits an α2βδγ composition, while the adult AChR expressed after birth in innervated muscle exhibits an α2βδγ composition [4]. The α-subunit contains the main epitopes recognized by MG autoantibodies [2]. The human muscle AChR…

DenervationGene isoformmedicine.medical_specialtyanimal structuresThymomaBiologymusculoskeletal systemmedicine.diseaseMolecular biologyEpitopeMyasthenia gravisNeuromuscular junctionEndocrinologymedicine.anatomical_structureInternal medicinemedicineReceptortissuesAcetylcholine receptor
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Evolution of a Non-Hermitian Quantum Single-Molecule Junction at Constant Temperature

2021

This work concerns the theoretical description of the quantum dynamics of molecular junctions with thermal fluctuations and probability losses. To this end, we propose a theory for describing non-Hermitian quantum systems embedded in constant-temperature environments. Along the lines discussed in [A. Sergi et al., Symmetry 10 518 (2018)], we adopt the operator-valued Wigner formulation of quantum mechanics (wherein the density matrix depends on the points of the Wigner phase space associated to the system) and derive a non-linear equation of motion. Moreover, we introduce a model for a non-Hermitian quantum single-molecule junction (nHQSMJ). In this model the leads are mapped to a tunneling…

Density matrixQuantum dynamicsmolecular junction; non-Hermitian quantum mechanics; open quantum system dynamics; quantum thermodynamics; Quantum Physics; Quantum Physics; 80M99 81-08 81-10 81P99General Physics and AstronomyFOS: Physical scienceslcsh:Astrophysics02 engineering and technology01 natural sciencesArticle81-1003.67.PpQuantum stateQuantum mechanicslcsh:QB460-4660103 physical sciences80M9931.15.xglcsh:Science010306 general physicsQuantum thermodynamicsQuantumnon-Hermitian quantum mechanicsQuantum tunnelling05.30.-dPhysicsQuantum PhysicsOperator (physics)80M99 81-08 81-10 81P9981-08021001 nanoscience & nanotechnologyopen quantum system dynamicslcsh:QC1-99981P99Phase space05.60.Ggquantum thermodynamicslcsh:Q0210 nano-technologyQuantum Physics (quant-ph)molecular junctionlcsh:Physics02.60.Cb
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Enhanced chemosensing of ammonia based on the novel molecular semiconductor-doped insulator (MSDI) heterojunctions

2011

Abstract A series of new molecular semiconductor-doped insulator (MSDI) heterojunctions as conductimetric transducers to NH3 sensing were fabricated based on a novel semiconducting molecular material, an amphiphilic tris(phthalocyaninato) rare earth triple-decker complex, Eu2[Pc(15C5)4]2[Pc(OC10H21)8], quasi-Langmuir–Shafer (QLS) film, as a top-layer, and vacuum-deposited and cast film of CuPc as well as copper tetra-tert-butyl phthalocyanine (CuTTBPc) QLS film as a sub-layer, named as MSDIs 1, 2 and 3, respectively. MSDIs 1–3 and respective sub-layers prepared from three different methods were characterized by X-ray diffraction, electronic absorption spectra and current–voltage (I–V) measu…

DiffractionMaterials scienceAbsorption spectroscopyDopingMetals and AlloysAnalytical chemistrychemistry.chemical_elementHeterojunctionCondensed Matter PhysicsCopperSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialschemistry.chemical_compoundchemistryMaterials ChemistryPhthalocyanineCrystalliteElectrical and Electronic EngineeringScience technology and societyInstrumentationSensors and Actuators B: Chemical
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A comparative study of heterostructured CuO/CuWO4 nanowires and thin films

2017

Authors are grateful to Reinis Ignatans for XRD measurements.

DiffractionMaterials scienceAnnealing (metallurgy)NanowireNanotechnology02 engineering and technology010402 general chemistry01 natural sciences7. Clean energyInorganic ChemistryA1. Nanostructures:NATURAL SCIENCES:Physics [Research Subject Categories]Materials ChemistryThin filmSpectroscopyA1. Crystal morphologyB1. OxidesB1. TungstatesHeterojunctionA1. CharacterizationSputter deposition021001 nanoscience & nanotechnologyCondensed Matter Physics0104 chemical sciencesAmorphous solidChemical engineering0210 nano-technologyJournal of Crystal Growth
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Diffraction-managed superlensing using metallodielectric heterostructures

2012

We show that subwavelength diffracted wave fields may be managed inside multilayered plasmonic devices to achieve ultra-resolving lensing. For that purpose we first transform both homogeneous waves and a broad band of evanescent waves into propagating Bloch modes by means of a metal/dielectric (MD) superlattice. Beam spreading is subsequently compensated by means of negative refraction in a plasmon-induced anisotropic effective-medium that is cemented behind. A precise design of the superlens doublet may lead to nearly aberration-free images with subwavelength resolution in spite of using optical paths longer than a wavelength. This research was funded by the Spanish Ministry of Economy and…

DiffractionPhysicsSuperlensbusiness.industrySuperlatticePhysics::OpticsHeterojunctionDielectricImagingWavelengthPlasmonic devicesOpticsNegative refractionSuper-resolutionOptoelectronicsbusinessPlasmonÓptica
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Sol-gel synthesis and photocatalytic activity of ZnO-SnO2 nanocomposites

2014

Abstract ZnO–SnO 2 nanocomposites were synthesized by a facile sol–gel synthesis route and characterized through X-ray diffraction, BET specific surface area analysis, UV–vis diffuse reflectance spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy. The photocatalytic activity of the samples was tested using the degradation of 4-nitrophenol under UV light as model reaction. The ZnO/SnO 2 molar ratio was varied in order to study its influence on the photoefficiency of the samples. The ZnO–SnO 2 nanocomposites showed higher photoactivity than the pure oxides and in particular the sample with ZnO/SnO 2 mol…

Diffuse reflectance infrared fourier transformChemistryScanning electron microscopeProcess Chemistry and TechnologyAnalytical chemistryHeterojunctionCatalysisZnO-SnO2 nanocompositePhotocatalysiX-ray photoelectron spectroscopyHeterojunction effectSpecific surface areaPhotocatalysisPhotocatalysis; ZnO-SnO2 nanocomposites; Sol-gel method; Heterojunction effectSettore CHIM/07 - Fondamenti Chimici Delle TecnologiePhysical and Theoretical ChemistrySpectroscopySol-gel methodSol-gel
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Optimization of impurity profile for p-n junction in heterostructures

2005

We analyze the dopant diffusion in p-n-junction in heterostructure, by solving the diffusion equation with space-varying diffusion coefficient. For a step-wise spatial distribution we find the optimum annealing time to decrease the p-n-junction thickness and to increase the homogeneity of impurity concentration in p or n regions.

Diffusion equationMaterials scienceDopantCondensed matter physicsEpitaxial layerAnnealing (metallurgy)radiation defectsHeterojunctionCondensed Matter::Mesoscopic Systems and Quantum Hall EffectCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsCondensed Matter::Materials ScienceImpurityCondensed Matter::SuperconductivityHomogeneity (physics)Effective diffusion coefficientHeterojunctionp–n junctionOptimization of impurity
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Quasi Conjunction and Inclusion Relation in Probabilistic Default Reasoning

2011

We study the quasi conjunction and the Goodman & Nguyen inclusion relation for conditional events, in the setting of probabilistic default reasoning under coherence. We deepen two recent results given in (Gilio and Sanfilippo, 2010): the first result concerns p-entailment from a family F of conditional events to the quasi conjunction C(S) associated with each nonempty subset S of F; the second result, among other aspects, analyzes the equivalence between p-entailment from F and p-entailment from C(S), where S is some nonempty subset of F. We also characterize p-entailment by some alternative theorems. Finally, we deepen the connections between p-entailment and the Goodman & Nguyen inclusion…

Discrete mathematicsClass (set theory)goodman & nguyen inclusion relationSettore MAT/06 - Probabilita' E Statistica MatematicaSettore INF/01 - Informaticap-entailment.; quasi conjunction; goodman & nguyen inclusion relation; qand rule; coherence; probabilistic default reasoning; p-entailmentProbabilistic logicqand ruleprobabilistic default reasoningConsistency (knowledge bases)Coherence (philosophical gambling strategy)p-entailmentCoherence probabilistic default reasoning quasi conjunction Goodman & Nguyen inclusion relation QAND rule p-entailment.coherenceConjunction (grammar)Default reasoningquasi conjunctionGreatest elementAlgorithmEquivalence (measure theory)Mathematics
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From quantale algebroids to topological spaces: Fixed- and variable-basis approaches

2010

Using the category of quantale algebroids the paper considers a generalization of the classical Papert-Papert-Isbell adjunction between the categories of topological spaces and locales to partial algebraic structures. It also provides a single framework in which to treat the concepts of quasi, standard and stratified fuzzy topology.

Discrete mathematicsPure mathematicsBasis (linear algebra)LogicAlgebraic structureGeneralizationQuantaleTopological spaceAdjunctionArtificial IntelligenceMathematics::Category TheoryCategory of topological spacesQuantaloidMathematicsFuzzy Sets and Systems
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Homotopy limits for 2-categories

2008

AbstractWe study homotopy limits for 2-categories using the theory of Quillen model categories. In order to do so, we establish the existence of projective and injective model structures on diagram 2-categories. Using these results, we describe the homotopical behaviour not only of conical limits but also of weighted limits. Finally, pseudo-limits are related to homotopy limits.

Discrete mathematicsPure mathematicsHomotopy lifting propertyHomotopy categoryGeneral MathematicsHomotopyHomotopiaQuillen adjunctionWhitehead theoremCofibrationMathematics::Algebraic Topologyn-connectedCategories (Matemàtica)Mathematics::K-Theory and HomologyHomotopy hypothesisMathematics::Category Theory512 - Àlgebra2-categories homotopy limits coherence conditionsMathematics
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