Search results for " Open"

showing 10 items of 439 documents

Protecting quantum resources via frequency modulation of qubits in leaky cavities

2018

Finding strategies to preserve quantum resources in open systems is nowadays a main requirement for reliable quantum-enhanced technologies. We address this issue by considering structured cavities embedding qubits driven by a control technique known as frequency modulation. We first study a single qubit in a lossy cavity to determine optimal modulation parameters and qubit-cavity coupling regime allowing a gain of four orders of magnitude concerning coherence lifetimes. We relate this behavior to the inhibition of the qubit effective decay rate rather than to stronger memory effects (non-Markovianity) of the system. We then exploit these findings in a system of noninteracting qubits embedde…

Quantum PhysicsMultidisciplinaryQuantum decoherenceComputer sciencelcsh:Rlcsh:MedicineFOS: Physical sciencesQuantum entanglementTopology01 natural sciencesSettore FIS/03 - Fisica Della Materia010305 fluids & plasmasEntanglement open quantum systems protection of quantum correlations frequency modulationQubit0103 physical scienceslcsh:Qlcsh:Science010306 general physicsQuantum Physics (quant-ph)QuantumFrequency modulationCoherence (physics)Quantum computer
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Structure of longitudinal chromomagnetic fields in high energy collisions

2014

We compute expectation values of spatial Wilson loops in the forward light cone of high-energy collisions. We consider ensembles of gauge field configurations generated from a classical Gaussian effective action as well as solutions of high-energy renormalization group evolution with fixed and running coupling. The initial fields correspond to a color field condensate exhibiting domain-like structure over distance scales of order the saturation scale. At later times universal scaling emerges at large distances for all ensembles, with a nontrivial critical exponent. Finally, we compare the results for the Wilson loop to the two-point correlator of magnetic fields.

We compute expectation values of spatial Wilson loops in the forward light cone of high-energy collisions. We consider ensembles of gauge field configurations generated from a classical Gaussian effective action as well as solutions of high-energy renormalization group evolution with fixed and running coupling. The initial like structure over distance scales of oder the saturation scale. At later times universal scaling emerges at large distances for all ensembles with a nontrivial critical exponent. Finally we compare the resulats for the Wilson loop to the two-point correlator of magnetic fields. (C) 2014 The Authors. Published by Elsevier BV This is an open access article under the CC BY licenseNuclear and High Energy PhysicsWilson loopLARGE NUCLEINuclear TheoryField (physics)FOS: Physical sciences114 Physical sciences01 natural sciencesColor-glass condensateRENORMALIZATION-GROUPNuclear Theory (nucl-th)GLUON DISTRIBUTION-FUNCTIONSHigh Energy Physics - Phenomenology (hep-ph)Light cone0103 physical sciencesSCATTERINGGauge theory010306 general physicsSMALL-XEffective actionPhysicsCORRELATORSta114010308 nuclear & particles physicsCOLOR GLASS CONDENSATERenormalization groupEVOLUTIONJIMWLK EQUATIONHigh Energy Physics - PhenomenologySATURATIONQuantum electrodynamicsCritical exponentPhysics Letters B
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Robust non-Markovianity in ultracold gases

2012

We study the effect of thermal fluctuations on a probe qubit interacting with a Bose-Einstein condensed (BEC) reservoir. The zero-temperature case was studied in [Haikka P et al 2011 Phys. Rev. A 84 031602], where we proposed a method to probe the effects of dimensionality and scattering length of a BEC based on its behavior as an environment. Here we show that the sensitivity of the probe qubit is remarkably robust against thermal noise. We give an intuitive explanation for the thermal resilience, showing that it is due to the unique choice of the probe qubit architecture of our model.

PhysicsCondensed Matter::Quantum GasesWork (thermodynamics)Quantum PhysicsCold Atoms Open Quantum System Markovian Master equations/dk/atira/pure/subjectarea/asjc/3100/3107/dk/atira/pure/subjectarea/asjc/3100/3104Thermal fluctuationsFOS: Physical sciencesScattering lengthPhysics and Astronomy(all)Condensed Matter PhysicsSettore FIS/03 - Fisica Della MateriaAtomic and Molecular Physics and Optics/dk/atira/pure/subjectarea/asjc/3100Quantum Gases (cond-mat.quant-gas)Quantum mechanicsQubitThermalSensitivity (control systems)Condensed Matter - Quantum Gases/dk/atira/pure/subjectarea/asjc/2600/2610Quantum Physics (quant-ph)Mathematical PhysicsCurse of dimensionality
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A Randomized Trial of a Schlemm's Canal Microstent with Phacoemulsification for Reducing Intraocular Pressure in Open-Angle Glaucoma

2014

Purpose To assess the safety and effectiveness of the Hydrus Microstent (Ivantis, Inc, Irvine, CA) with concurrent cataract surgery (CS) for reducing intraocular pressure (IOP) in open-angle glaucoma (OAG). Design Prospective, multicenter, randomized, single-masked, controlled clinical trial. Participants One hundred eyes from 100 patients 21 to 80 years of age with OAG and cataract with IOP of 24 mmHg or less with 4 or fewer hypotensive medications and a washed-out diurnal IOP (DIOP) of 21 to 36 mmHg. Methods On the day of surgery, patients were randomized 1:1 to undergo CS with the microstent or CS alone. Postoperative follow-up was at 1 day, 1 week, and 1, 3, 6, 12, 18, and 24 months. Wa…

MaleIntraocular pressureVisual acuityMinimally invasive glaucoma surgerymedicine.medical_treatmentVisual AcuityGlaucomalaw.inventionRandomized controlled trialLens Implantation Intraocularlaw80 and overMedicineSingle-Blind MethodProspective StudiesProspective cohort studyGlaucoma Drainage ImplantsAged 80 and overIntraocularMedicine (all)Adult; Aged; Aged 80 and over; Antihypertensive Agents; Female; Follow-Up Studies; Glaucoma Open-Angle; Humans; Intraocular Pressure; Lens Implantation Intraocular; Limbus Corneae; Male; Middle Aged; Prospective Studies; Prosthesis Implantation; Single-Blind Method; Tonometry Ocular; Visual Acuity; Visual Fields; Young Adult; Glaucoma Drainage Implants; Phacoemulsification; Stents; Ophthalmology; Medicine (all)Middle AgedOpen-AngleFemaleStentsmedicine.symptomLens ImplantationGlaucoma Open-AngleAdultmedicine.medical_specialtyLimbus CorneaeTonometryProsthesis ImplantationTonometry OcularYoung AdultOphthalmologyOcularHumansAntihypertensive AgentsIntraocular PressureAgedPhacoemulsificationbusiness.industryGlaucomaPhacoemulsificationCataract surgerymedicine.diseaseOphthalmologyVisual FieldsbusinessFollow-Up Studies
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The use of carrageenan for limiting the mandibular movement in rats: A preliminary experimental study

2009

Purpose: The objective of this study was to evaluate if the carrageenan may be used for limiting the mandibular movement. Material and Methods: Eighteen adult male Wistar rats were used for the research, 20 µl of carrageenan (4%) was infiltrated in the extra articular region, in front of the condyle to induce fibrosis. The rats were divided into groups according to the time of euthanasia (7, 15 and 30 days). Maximal mouth opening (MMO), mandibular deviation, initial and final weights were recorded and evaluated. After the euthanasia, the specimens were submitted to histological study in order to classify the inflammatory process using scores. Results: The mean differences between initial an…

Malemedicine.medical_specialtyAdult maleMovementDentistryMandibleCarrageenanCondylechemistry.chemical_compoundFibrosisMandibular deviationmedicineAnimalsRats WistarGeneral Dentistrybusiness.industryLimiting:CIENCIAS MÉDICAS [UNESCO]medicine.diseaseRatsSurgeryCarrageenanMouth openingOtorhinolaryngologychemistryUNESCO::CIENCIAS MÉDICASSurgerybusinessMedicina Oral Patología Oral y Cirugia Bucal
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Inter-joint coordination of posture on a seesaw device

2016

Even though specific adjustments of the multi-joint control of posture have been observed when posture is challenged, multi-joint coordination on a seesaw device has never been accurately assessed. The current study was conducted in order to investigate the multi-joint coordination when subjects were standing on either a seesaw device or on a stable surface, with the eyes open or closed. Eighteen healthy active subjects were recruited. A principal component analysis and a Self-Organizing Maps analysis were performed on the joint angles in order to detect and characterize dominant coordination patterns. Intermuscular EMG coherence was analysed in order to assess the neurophysiological mechan…

AdultMaleComputer sciencePostureBiophysicsNeuroscience (miscellaneous)Postural control03 medical and health sciences0302 clinical medicineSeesaw molecular geometryControl theorymedicineHumansMuscle SkeletalPostural BalanceJoint (geology)Eyes openVision OcularPrincipal Component AnalysisProprioception030229 sport sciencesNeurophysiologymedicine.anatomical_structureFemaleNeurology (clinical)AnkleAnkleAnkle JointPsychomotor Performance030217 neurology & neurosurgeryCoherence (physics)Journal of Electromyography and Kinesiology
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Mappings of Finite Distortion : Compactness of the Branch Set

2017

We show that an entire branched cover of finite distortion cannot have a compact branch set if its distortion satisfies a certain asymptotic growth condition. We furthermore show that this bound is strict by constructing an entire, continuous, open and discrete mapping of finite distortion which is piecewise smooth, has a branch set homeomorphic to an (n - 2)-dimensional torus and distortion arbitrarily close to the asymptotic bound. Peer reviewed

General Mathematicsbranch setsCOVERS01 natural sciencesfunktioteoriaSet (abstract data type)Mathematics - Geometric TopologyDimension (vector space)DistortionFOS: Mathematics111 Mathematicsfinite distortionComplex Variables (math.CV)topologia0101 mathematicsDIMENSIONMathematicsPartial differential equationMathematics - Complex Variables010102 general mathematicsMathematical analysisGeometric Topology (math.GT)TorusCompact spaceCover (topology)57M12 30C65PiecewiseLIGHT OPEN MAPSmonistotAnalysis
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Analytic gradients for Mukherjee’s multireference coupled-cluster method using two-configurational self-consistent-field orbitals

2010

Analytic gradients for the state-specific multireference coupled-cluster method suggested by Mahapatra et al. [Mol. Phys. 94, 157 (1998)] (Mk-MRCC) are reported within the singles and doubles approximation using two-configurational self-consistent field (TCSCF) orbitals. The present implementation extends our previous work on Mk-MRCC gradients [E. Prochnow et al., J. Chem. Phys. 131, 064109 (2009)] which is based on restricted Hartree-Fock orbitals and consequently the main focus of the present paper is on the treatment of orbital relaxation at the TCSCF level using coupled-perturbed TCSCF theory. Geometry optimizations on m-arynes and nitrenes are presented to illustrate the influence of t…

Coupled clusterLinear combination of atomic orbitalsChemistryQuantum mechanicsRestricted open-shell Hartree–FockGeneral Physics and AstronomyMolecular orbital theoryMolecular orbitalComplete active spacePhysical and Theoretical ChemistrySlater-type orbitalBasis setThe Journal of Chemical Physics
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Time-based Chern number in periodically driven systems in the adiabatic limit

2023

To define the topology of driven systems, recent works have proposed synthetic dimensions as a way to uncover the underlying parameter space of topological invariants. Using time as a synthetic dimension, together with a momentum dimension, gives access to a synthetic two-dimensional (2D) Chern number. It is, however, still unclear how the synthetic 2D Chern number is related to the Chern number that is defined from a parametric variable that evolves with time. Here we show that in periodically driven systems in the adiabatic limit, the synthetic 2D Chern number is a multiple of the Chern number defined from the parametric variable. The synthetic 2D Chern number can thus be engineered via h…

General Physics and AstronomyTDDFT Open boundary conditionsSettore FIS/03 - Fisica Della MateriaPhysical Review Research
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New insights into autoantibody profiles from immune privileged sites in the eye: a glaucoma study.

2011

Glaucoma is a chronic neurodegenerative disease and one of the leading causes of blindness. Autoantibody based immune processes are assumed to be involved in its pathogenesis. However, it is still unclear to what extent autoantibody patterns found in the eye (aqueous humor) are congruent to systemic autoantibodies (blood). Consistency would underline the specificity of known serum antibody markers for glaucoma. In this study we used antigen microarrays to analyze autoantibody reactivities in sera and corresponding aqueous humor samples of primary open-angle glaucoma patients (N=37) and non-glaucomatous controls (N=31). Compared to control subjects several divergent immunoreactivities were i…

MalePathologymedicine.medical_specialtygenetic structuresImmunologyGlaucomaDiseaseCataract ExtractionEyePathogenesisAqueous HumorBehavioral NeuroscienceImmune systemAntigenArtificial IntelligencemedicineHumansAntigensAgedAutoantibodiesbiologyEndocrine and Autonomic Systemsbusiness.industryMicroarray analysis techniquesAutoantibodymedicine.diseaseMicroarray Analysiseye diseasesArea Under CurveImmunoglobulin GImmunologybiology.proteinFemaleOcular Hypertensionsense organsNeural Networks ComputerAntibodybusinessAlgorithmsGlaucoma Open-AngleBrain, behavior, and immunity
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