Search results for "Dynamic"

Effect of stiffness on the phase behavior of cubic lattice chains

2005

Gran canonica Monte Carlo (GCMC) simulazioni assistite da tecniche di riponderazione istogramma sono stati utilizzati per studiare l'effetto della flessibilità catena sul comportamento di soluzione fase di cubi catene reticolari corti con 4-32 segmenti. Ciò è stato fatto variando un parametro di rigidità gradualmente fino alla media calcolata end-to-end distanza avvicinato la lunghezza totale. Per entrambe le catene flessibili e rigide si è riscontrato che la temperatura critica, ottenuta tramite mista analisi dei campi di dimensioni finite, aumentata lunghezza della catena e la densità critica trasferisce a valori più bassi, in accordo con le osservazioni sperimentali. Il estrapolato lungh…

The one loop gluon emission light cone wave function

2017

Light cone perturbation theory has become an essential tool to calculate cross sections for various small-$x$ dilute-dense processes such as deep inelastic scattering and forward proton-proton and proton-nucleus collisions. Here we set out to do one loop calculations in an explicit helicity basis in the four dimensional helicity scheme. As a first process we calculate light cone wave function for one gluon emission to one-loop order in Hamiltonian perturbation theory on the light front. We regulate ultraviolet divergences with transverse dimensional regularization and soft divergences with using a cut-off on longitudinal momentum. We show that when all the renormalization constants are comb…

CONFLICT DYNAMICS IN HEALTHCARE SERVICES: AN EXPERIMENTAL STUDY USING THE SYSTEM DYNAMICS METHODOLOGY

Σκοπός Η μελέτη αυτή χρησιμοποιεί τη συστημική προσέγγιση για να διερευνήσει τη δυναμική της μάθησης και του αρνητικού συναισθήματος στις συγκρούσεις μεταξύ εργαζομένων στο χώρο της υγείας. Η δυναμική μας υπόθεση ήταν ότι η αλληλεπίδραση μεταξύ των επιπέδων σύγκρουσης, πληροφορίας/μάθησης και αρνητικών συναισθημάτων που συσσωρεύονται στο χώρο εργασίας ως παραπροϊόντα της σύγκρουσης προκαλούν ενδογενώς την διακύμανση (ταλαντώσεις) των επιπέδων σύγκρουσης. Υλικό-Μέθοδος Πραγματοποιήθηκε αρχικά μια συστηματική ανασκόπηση της βιβλιογραφίας και εντοπίσθηκαν 2 προβληματικά πρότυπα εξέλιξης των εργασιακών συγκρούσεων με την πάροδο του χρόνου (Group Disintegration, Groupthink) και ένα "επιθυμητό" π…

Tracking Ca2+ ATPase intermediates in real time by x-ray solution scattering

2020

Sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) transporters regulate calcium signaling by active calcium ion reuptake to internal stores. Structural transitions associated with transport have been characterized by x-ray crystallography, but critical intermediates involved in the accessibility switch across the membrane are missing. We combined time-resolved x-ray solution scattering (TR-XSS) experiments and molecular dynamics (MD) simulations for real-time tracking of concerted SERCA reaction cycle dynamics in the native membrane. The equilibrium [Ca2] E1 state before laser activation differed in the domain arrangement compared with crystal structures, and following laser-induced release o…

CFD simulation of ZnO nanoparticle precipitation in a supercritical water synthesis reactor

2012

International audience; Continuous hydrothermal flow synthesis process has shown great advantages concerning the control of particle size and morphology through the optimization of supercritical water processing parameters. In particular, micromixing is a key issue of the process for controlling the nucleation mechanism. A Computational Fluid Dynamics (CFD) model is suggested for nanoparticle size determination using a population balance approach. Models for reaction kinetics, thermodynamics, nucleation and growth are presented. The effects of base concentration and hydrodynamics are investigated. Results show that the CFD may be valuable simulation tool for controlling the size and the sha…

Controlling molecular alignment rephasing through interference of Raman-induced rotational coherence

2000

0021-9606; Quantum control over molecular alignment rephasing is experimentally investigated in gaseous CO2. The control process is achieved by illuminating the medium with a pair of pump-pulses separated in time by approximately an integer value of T0=1/8B(0), where B(0) is the rotational constant. Through a Raman-type process, each pulse alone produces rotational coherence leading to a periodic orientational anisotropy. It is the combination of the two pulses that yields to quantum interference, resulting in a modification of this anisotropy probed by a third delayed pulse. The effect is accurately analyzed for different time delays between the two pulses. A theoretical analysis supplies …

Influence of metal ions on thermal aggregation of bovine serum albumin: aggregation kinetics and structural changes

2009

Metal ions are implicated in protein aggregation processes of several neurodegenerative pathologies. In this work the effects of Cu(II) and Zn(II) ions on heat-induced structural modifications of bovine serum albumin (BSA) were studied, with the aim of delineating the role of these ions in the early stages of proteins aggregation kinetics. A joint application of different techniques was used. The aggregate growth was followed by dynamic light scattering measurements, whereas the conformational changes occurring in the protein structure were monitored by Raman and IR spectroscopy. Both in absence and in presence of metal ions, heating treatment gave rise to b-structures to the detriment of a…

Quantum interference and the time-dependent radiation of nanojunctions

2021

Using the recently developed time-dependent Landauer-B\"uttiker formalism and Jefimenko's retarded solutions to the Maxwell equations, we show how to compute the time-dependent electromagnetic field produced by the charge and current densities in nanojunctions out of equilibrium. We then apply this formalism to a benzene ring junction, and show that geometry-dependent quantum interference effects can be used to control the magnetic field in the vicinity of the molecule. Then, treating the molecular junction as a quantum emitter, we demonstrate clear signatures of the local molecular geometry in the non-local radiated power.

CORPORATE VENTURE CAPITAL SYNDICATION STRATEGIES: A DYNAMIC NETWORK PERSPECTIVE

2018

Corporate Venture Capital (CVC) syndication is embraced by over 80% of corporates which co-investing the same startups with other corporates create a CVC syndication network. In this paper, we aim at exploring the evolutionary dynamics of the CVC syndication network. Specifically, we address this topic adopting two different perspectives. First, we investigate the architectural evolution of the CVC syndication network examining five dimensions that characterize the evolution of the network structure (i.e. degree distribution, connectivity, clustering, density and degree assortativity). In addition, we study how three network strategies (i.e. prominence, entrepreneurial and relational) evolv…

Bacteria Associated with Copestylum (Diptera, Syrphidae) Larvae and Their Cactus Host Isolatocereus dumortieri

2011

We describe the gut bacterial diversity inhabiting two saprophagous syrphids and their breeding substrate (decayed tissues of the columnar cactus Isolatocereus dumortieri). We analyzed the gut microbiota of Copestylum latum (scooping larvae that feed on decayed cactus tissues) and Copestylum limbipenne (whose larvae can also feed on semiliquid tissues) using molecular techniques. DNA was extracted from larval guts and cactus tissues. The V1-V3 region of the 16S rRNA genes was amplified and sequenced. A total of 31079 sequences were obtained. The main findings are: C. limbipenne is dominated by several Enterobacteriaceae, including putative nitrogen-fixing genera and pectinolitic species and…