Search results for " Dynamics"

Realization of time-resolved two-vacuum-ultraviolet-photon ionization

2009

International audience; Ultrafast dynamics of excited molecules is studied through time-resolved two-vacuum-ultraviolet (vuv)- photon ionization using a nonlinear volume autocorrelator unit. The two-vuv-photon process is induced by the intense fifth harmonic radiation of a femtosecond Ti:sapphire laser. In a proof-of-principle experiment, ultrafast dynamics of excited ethylene and oxygen molecules are investigated. Molecular decay times are deduced by comparing the experimental data with the results of a numerical model that accounts for the spatial and temporal characteristics of the harmonic field. The present experiments pave a convenient way for time domain investigations in the vuv-xuv s…

Spectroscopic studies of semiconducting single-walled carbon nanotubes

2010

The unique nature of optical properties of single-walled carbon nanotubes (SWCNT), together with their promising potential applications, have created enormous interest towards the photophysics of SWCNT. Many aspects of carbon nanotubes originate from the electronic structure of carbon honeycomb lattice and one-dimensionality. SWCNTs exist in various chiral structures and diameters, which the optical and electrical properties are dependent on. It has been discovered that SWCNT excited states are excitonic with strong Coulomb interaction between the electron and the hole. However, many features of excitons are not yet well defined, such as absorption cross-sections, fluorescence quantum yield…

Il dynamic business model: una prospettiva dinamica per la progettazione dei modelli di business

2017

Building on the extant literature on business modelling and focussing on start-up firms, this article aims at exploring the combination between conventional business model schemes and System Dynamics methodology with the intent to overcome those limitations related to a static design approach. By mapping the multiple key elements underlying value creation processes – linked according to a cause-and-effect perspective – and with the support of a simulation-based methodology, entrepreneurs may experiment and understand how the firm reacts to strategic and organizational changes in terms of performance, innovation and value creation.

Inferring directionality of coupled dynamical systems using Gaussian process priors: Application on neurovascular systems

2022

Dynamical system theory has recently shown promise for uncovering causality and directionality in complex systems, particularly using the method of convergent cross mapping (CCM). In spite of its success in the literature, the presence of process noise raises concern about CCM's ability to uncover coupling direction. Furthermore, CCM's capacity to detect indirect causal links may be challenged in simulated unidrectionally coupled Rossler-Lorenz systems. To overcome these limitations, we propose a method that places a Gaussian process prior on a cross mapping function (named GP-CCM) to impose constraints on local state space neighborhood comparisons. Bayesian posterior likelihood and…

Cosolutes affect structure and dynamics of myoglobin-trehalose amorphous systems: a FTIR and MD study

2013

Sulfonamide moiety as "molecular chimera" in the design of new drugs.

2021

Background: The -SO2NH- group is of great significance in modern pharmaceutical use since, in sulfa-drugs, it is possible to introduce easily chemical modifications, and even small changes may lead to an improved version of an already existing drug. Objective: This paper aims to describe updated information in the sulfonamide field with a particular focus on new mechanisms of action, especially if discovered by employing computational approaches. Methods: Research articles that focused on the use of the sulfonamide moiety for the design, synthesis, and in vitro/in vivo tests of various diseases were collected from various search engines like PubMed, Science Direct, Google Scholar, and Scop…

CO(2)-water supercritical mixtures: Test of a potential model against neutron diffraction data

2007

Abstract A neutron diffraction experiment on supercritical mixtures of water and CO 2 at two concentrations is presented. Data are analyzed within the EPSR framework and the water–water and water–CO 2 radial distribution functions are compared with those calculated by a Molecular Dynamics simulation performed by using the TIPS2 and EPM-M potential models for water and CO 2 respectively. It is found that the Molecular Dynamics simulation reproduces the overall shape of the site–site radial distribution functions, although missing a few subtle changes brought along when the CO 2 concentration is increased.

Finite-frequency spin susceptibility and spin pumping in superconductors with spin-orbit relaxation

2020

Static spin susceptibility of superconductors with spin-orbit relaxation has been calculated in the seminal work of A.A. Abrikosov and L.P. Gor'kov [Sov. Phys. JETP, {\bf 15}, 752 (1962)]. Surprisingly the generalization of this result to finite frequencies has not been done despite being quite important for the modern topic of superconducting spintronics. The present paper fills this gap by deriving the analytical expression for spin susceptibility. The time-dependent spin response is shown to be captured by the quasiclassical Eilenberger equation with collision integrals corresponding to the ordinary and spin-orbit scattering. Using the developed formalism we study the linear spin pumping…

Governing at the frontier of the European Commission : the case of seconded national officials

2005

Studies of executive institutions have largely dealt separately with national and international executive institutions (IEIs). This study unpacks and repacks four conflicting decision-making dynamics that unfolds at the frontier of IEIs – that is, at the institutional rim where national and international executive institutions meet, interact and collide. The empirical laboratory utilised is seconded national experts in the European Commission. The survey and interview data presented demonstrates that the decision-making behaviour of seconded national experts includes a mix of departmental (portfolio), epistemic (expert) and supranational behaviour. The suspicion early voiced by Coombes (197…

Scattering of Co-Current Surface Waves on an Analogue Black Hole

2018

We report on what is to our knowledge the first scattering experiment of surface waves on an accelerating transcritical flow, which in the analogue gravity context is described by an effective spacetime with a black-hole horizon. This spacetime has been probed by an incident co-current wave, which partially scatters into an outgoing countercurrent wave on each side of the horizon. The measured scattering amplitudes are compatible with the predictions of the hydrodynamical theory, where the kinematical description in terms of the effective metric is exact.