Search results for "threshold [resummation]"

showing 10 items of 126 documents

Clustering local tourism systems by threshold acceptance

2015

Despite the importance of tourism as a leading industry in the development of a country’s economy, there is a lack of criteria and methodologies for the detection, promotion and governance of local tourism systems. We propose a quantitative approach for the detection of local tourism systems that are optimal with respect to geographical, economic, and demographical criteria. To this end, we formulate the issue as an optimization problem, and we solve it by means of Threshold Acceptance, a meta-heuristic algorithm which does not require us to predefine the number of clusters and also does not require all geographic areas to belong to a cluster.

Optimization problemSettore INF/01 - InformaticaComputer scienceCorporate governancemedia_common.quotation_subjectRural tourismEnvironmental economicsPromotion (rank)Clustering Threshold Accepting Tourist Local SystemsSettore MAT/09 - Ricerca OperativaCluster analysisTourismmedia_commonTourist flow
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Photoelectrical properties of thin films of DMABI derivatives

2011

Organic thin films with semiconducting properties have been intensively studied in nowadays due to very promising applications in organic electronics, for example, organic photovoltaic. Among organic semiconductors, group of indandiones with their photoelectrical properties, thermal and chemical stability are good candidates for use in design of novel molecular electronic devices. We have investigated photoconductivity quantum efficiency and its spectral dependence of two dimetilaminobenzylidene-1,3-indandione derivatives. Values of the photoconductivity threshold energy and optical energy gap are obtained. These results are compared with calculated transfer energy gap estimated according t…

Organic semiconductorOrganic electronicsCondensed Matter::Materials ScienceMaterials sciencebusiness.industryAb initio quantum chemistry methodsPhotoconductivityOptoelectronicsQuantum efficiencyChemical stabilityThin filmbusinessThreshold energyIOP Conference Series: Materials Science and Engineering
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Analgesic and central depressor effects of the dichloromethanol extract fromSchinus molle L.

1997

The analgesic and central depressor effects of the dichloromethanol extract of Schinus molle L. were analysed in in vivo models. This extract showed low acute toxicity, CNS depressor activity and analgesic effect. Following further fractionation, the hexane/dichloromethane (75/25) fraction showed the most interesting results. Thus, this fraction caused a total inhibition of motor activity and significantly reduced the threshold of pain to chemical stimulus. © 1997 John Wiley & Sons, Ltd.

PharmacologySchinus mollebiologyTraditional medicineIn vivoChemistryThreshold of painAnalgesicToxicityBiological activityPharmacognosybiology.organism_classificationAcute toxicityPhytotherapy Research
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Time course of excitatory and inhibitory states of bulbar respiratory modulated neurons.

1980

In respiratory modulated neurons of rabbits, vagally mediated inhibition is not bound to resting membrane potential oscillations. Latency of spinally evoked antidromical spike invasion, however, is shorter and threshold voltage is lower during the shift of membrane potential towards depolarization accompanying burst discharge.

PharmacologySynaptic potentialMembrane potentialNeuronsSubthreshold membrane potential oscillationsChemistryBrainDepolarizationVagus NerveCell BiologyInhibitory postsynaptic potentialElectric StimulationCellular and Molecular NeuroscienceOxygen ConsumptionSpinal CordThreshold potentialAnesthesiaExcitatory postsynaptic potentialMolecular MedicineAnimalsRabbitsRespiratory systemMolecular BiologyNeuroscienceExperientia
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Evaluation of the acute toxicity, analgesic and CNS activities of different species ofTeucrium genus

1995

Methanol and dichloromethanol extracts of the leaves and stems of four Teucrium species (T. cartaginenses, T. flavum, T. pumillum and T. buxifolium) have been tested for their toxicity, analgesic and central depressor effects. The intraperitoneal administration of the different extracts showed a CNS depressant activity in mice, but they lacked anticonvulsive effects. When tested for analgesic activity none of the extracts increased the threshold of pain thermal stimulus. However, the methanol and dichloromethanol extracts of T. cartaginenses and T. buxifolium species showed a significant analgesic effect in models of pain induced by chemical or mechanical stimulation.

PharmacologybiologyChemistryTEUCRIUM CARTAGINENSES EXTRACTSTEUCRIUM FLAVUM EXTRACTSAnalgesicCentral nervous systemTEUCRIUM BUXIFOLIUM EXTRACTSStimulationBiological activityEFFECTS ON CNSPharmacologybiology.organism_classificationAcute toxicityTeucriumANALGESIAmedicine.anatomical_structureThreshold of painToxicitymedicineTEUCRIUM PUMILLUM EXTRACTSPhytotherapy Research
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Efficacy and Safety of Subthreshold Micropulse Yellow Laser for Persistent Diabetic Macular Edema After Vitrectomy: A Pilot Study

2022

Aim: To examine the effect of subthreshold micropulse yellow laser (SMYL) on best-corrected visual acuity (BCVA), central macular thickness (CMT), and optical coherence tomography angiography (OCT-A) changes in eyes with persistent diabetic macular edema (DME) after pars plana vitrectomy (PPV) for tractional DME (TDME).Patients and Methods: In a comparative study, 95 eyes of 95 consecutive patients with persistent DME were prospectively enrolled. The SMYL group (54 eyes) was treated with SMYL 6 months after PPV, while the control group (41 eyes) was followed up without treatment. BCVA and CMT by OCT were analyzed at baseline and 3 and 6 months. Additionally, parameters such as the vessel de…

Pharmacologydiabetic retinopathySettore MED/30 - Malattie Apparato VisivoinflammationOCT angiographysubthreshold micropulse laserPharmacology (medical)OCT angiography; diabetic retinopathy; inflammation; subthreshold micropulse laser; tractional DMEtractional DME
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The general expression for the transition amplitude of two-photon ionization of atomic hydrogen

2003

Two-photon ionization of atomic hydrogen with an excess photon is revisited. The non-relativistic dipole approximation and Coulomb Green function (CGF) formalism are applied. Using the CGF Sturmian expansion straightforwardly, one gets the radial transition amplitude in the form of an infinite sum over Gauss hypergeometric functions which are polynomials. It is convergent if all intermediate states are in the discrete spectrum. In the case of two-photon ionization with an excess photon, when photoionization is also possible, intermediate states are in the continuum. We performed the explicit summation over intermediate states and got a simple general expression for the radial transition amp…

PhysicsAbove threshold ionizationPhotoionizationCondensed Matter PhysicsAtomic and Molecular Physics and OpticsPositroniumAmplitudeExcited stateQuantum mechanicsIonizationPhysics::Atomic PhysicsHypergeometric functionAtomic physicsGround stateJournal of Physics B: Atomic, Molecular and Optical Physics
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Ionization of atomic hydrogen with up to four excess photons by circularly and linearly polarized light

2012

The above threshold ionization (ATI) is investigated for H in ns states. The total generalized cross sections are calculated for up to 4 excess photons using perturbation theory and modified Coulomb Green's function Sturmian expansion.

PhysicsHistoryPhotonHydrogenLinearly polarized lightAbove threshold ionizationchemistry.chemical_elementFunction (mathematics)Computer Science ApplicationsEducationchemistryIonizationCoulombPhysics::Atomic PhysicsAtomic physicsPerturbation theoryJournal of Physics: Conference Series
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The Z(3985) as a threshold effect from the D¯s⁎D+D¯sD⁎ interaction

2021

Abstract We study the e + e − → K + ( D s ⁎ − D 0 + D s − D ⁎ 0 ) reaction recently measured at BESIII, from where a new Z c s state has been reported. We study the interaction of D ¯ s D ⁎ with the coupled channels J / ψ K − , K ⁎ − η c , D s − D ⁎ 0 , D s ⁎ − D 0 by means of an extension to the charm sector of the local hidden gauge approach. We find that the D s − D ⁎ 0 + D s ⁎ − D 0 combination couples to J / ψ K − and K ⁎ − η c , but the D s − D ⁎ 0 − D s ⁎ − D 0 combination does not. The coupled channels help to build up strength in the D s − D ⁎ 0 + D s ⁎ − D 0 diagonal scattering matrix close to threshold and, although the interaction is not strong enough to produce a bound state or…

PhysicsNuclear and High Energy Physics010308 nuclear & particles physicsThreshold effect0103 physical sciencesBound stateAnalytical chemistryResonance010306 general physics01 natural sciencesPhysics Letters B
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EMMA – a new underground cosmic-ray experiment

2008

An experiment observing underground muons originating from cosmic-ray air showers is under preparation in the Pyhasalmi mine, Finland. The aim is to cover an area of about 200-300 m(2), and the detector setup is capable of measuring the muon multiplicity and their lateral distribution. The detector is placed at a depth of about 85 m (corresponding about 240 m w.e.), which gives a threshold energy of muons of about 45 GeV. The detection of the multimuon events is motivated by partly unknown composition of the primary cosmic rays in the energy region of 10(15)-10(16) eV, i.e., the knee region. In addition, by measuring only the higher energy muons of the air shower, the lowest energy muons be…

PhysicsNuclear and High Energy PhysicsMuonLarge Hadron ColliderPhysics::Instrumentation and DetectorsAstrophysics::High Energy Astrophysical PhenomenaDetectorCosmic rayThreshold energyAtomic and Molecular Physics and OpticsParticle detectorParticle identificationNuclear physicsAir showerHigh Energy Physics::ExperimentNuclear Physics B - Proceedings Supplements
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