Fast spontaneous emission and high F\"orster resonance energy transfer rate in hybrid organic/inorganic plasmonic nanostructures

We report an experimental study of the plasmon-assisted spontaneous emission and the F\"orster resonance energy transfer between organic molecules and semiconductor colloidal quantum dots. The localized plasmonic field in the nanogap between a gold nano-popcorn's tips and a 5-nm separated gold film supports high photonic density of states and provides pathways for the light-matter interaction mechanisms. We demonstrate that, besides the total spontaneous emission rate enhancement factor up to 66 for quantum dots and molecules, the F\"orster resonance energy transfer efficiency and rate constant are simultaneously modified. While the energy transfer efficiency is reduced from 84 to 35 per cent due to the non-radiative quenching effect and fast donor spontaneous emission rate, the energy transfer rate constant is significantly increased from 4 to 20 ns-1. Our results have quantitatively elucidated decay mechanisms that are important toward understanding and controlling of the light-matter interaction at the nanoscale.Comment: 12 pages, 4 Figures, Submitte

Input Device Selection and Interaction Configuration with ICON

International audienceThis paper describes ICON, a novel editor designed to configure a set of input devices and connect them to actions into a graphical interactive application. ICON allows physically challenged users to connect alternative input devices and/or configure their interaction techniques according to their needs. It allows skilled users - graphic designers or musicians for example - to configure any ICON aware application to use their favorite input devices and interaction techniques (bimanual, voice enabled, etc.). ICON works with Java Swing and requires applications to describe their interaction styles in terms of ICON modules. By using ICON, users can adapt more deeply than before their applications and programmers can easily provide extensibility to their applications

Coupled evolution of BrOx-ClOx-HOx-NOx chemistry during bromine-catalyzed ozone depletion events in the arctic boundary layer

Extensive chemical characterization of ozone (O3) depletion events in the Arctic boundary layer during the TOPSE aircraft mission in March-May 2000 enables analysis of the coupled chemical evolution of bromine (BrOx), chlorine (ClOx), hydrogen oxide (HOx) and nitrogen oxide (NOx) radicals during these events. We project the TOPSE observations onto an O3 chemical coordinate to construct a chronology of radical chemistry during O3 depletion events, and we compare this chronology to results from a photochemical model simulation. Comparison of observed trends in ethyne (oxidized by Br) and ethane (oxidized by Cl) indicates that ClOx chemistry is only active during the early stage Of O3 depletion (O3 > 10 ppbv). We attribute this result to the suppression of BrCl regeneration as O3 decreases. Formaldehyde and peroxy radical concentrations decline by factors of 4 and 2 respectively during O3 depletion and we explain both trends on the basis of the reaction of CH2O with Br. Observed NOx concentrations decline abruptly in the early stages Of O3 depletion and recover as O3 drops below 10 ppbv. We attribute the initial decline to BrNO3 hydrolysis in aerosol, and the subsequent recovery to suppression of BrNO3 formation as O3 drops. Under halogen-free conditions we find that HNO4 heterogeneous chemistry could provide a major NOx sink not included in standard models. Halogen radical chemistry in the model can produce under realistic conditions an oscillatory system with a period of 3 days, which we believe is the fastest oscillation ever reported for a chemical system in the atmosphere

The controversy in the γγ→ρρ\gamma\gamma\to\rho\rho process: potential scattering or qqqˉqˉqq\bar{q}\bar{q} resonance ?

The $\gamma\gamma\to\rho^0\rho^0\to 4 \pi$ reaction shows a broad peak at 1.5 GeV in the $(J^P,J_z)=(2^+,2)$ channel which has no counterpart in the $\rho^+\rho^-$ channel. This "resonance" is considered as a candidate for a $qq\bar q\bar q$ state in the "s-channel". We show, however, that it can also be explained by potential scattering of $\rho^0\rho^0$ via the $\sigma$- exchange in the "t-channel".Comment: 12 pages, latex, 3 postscript figures, to appear in Zeitschrift fur Physi

Effect of systemic corticosteroid therapy for acute heart failure patients with elevated C-reactive protein

The current study explores whether degree of inflammation, reflected by C-reactive protein (CRP) level, modifies the effect of intravenous (IV) corticosteroid administered in the emergency department (ED) on clinical outcomes in patients with acute heart failure (AHF).We selected patients diagnosed with AHF in the ED, with confirmed N-terminal pro-B-type natriuretic peptide > 300 pg/mL and CRP > 5 mg/L in the ED from the Epidemiology of Acute Heart Failure in the Emergency Departments (EAHFE) registry. In these 1109 patients, 121 were treated by corticosteroid. The corticosteroid therapy hazard ratio (HR) for 30 day all-cause mortality was 1.26 [95% confidence interval (CI) 0.75-2.09, P = 0.38]. Although not statistically significant, HRs tended to decrease with increasing CRP level, with point estimates favouring corticosteroid at CRP levels above 20. In patients with CRP > 40 mg/L, with adjusted HRs of 0.56 (95% CI 0.20-1.55, P = 0.27) for 30 day all-cause mortality, 0.92 (95% CI 0.52-1.62, P = 0.78) for 30 day post-discharge ED revisit, hospitalization, or death, and adjusted odds ratio of 0.61 (95% CI 0.17-2.14, P = 0.44) for in-hospital all-cause mortality.The present analysis suggests that corticosteroids might have the potential to improve outcomes in AHF patients with inflammatory activation. Larger, prospective studies of anti-inflammatory therapy should be considered to assess potential benefit in patients with the highest degree of inflammation.© 2022 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology

A Tunable Two-impurity Kondo system in an atomic point contact

Two magnetic atoms, one attached to the tip of a Scanning Tunneling Microscope (STM) and one adsorbed on a metal surface, each constituting a Kondo system, have been proposed as one of the simplest conceivable systems potentially exhibiting quantum critical behaviour. We have succeeded in implementing this concept experimentally for cobalt dimers clamped between an STM tip and a gold surface. Control of the tip-sample distance with sub-picometer resolution allows us to tune the interaction between the two cobalt atoms with unprecedented precision. Electronic transport measurements on this two-impurity Kondo system reveal a rich physical scenario which is governed by a crossover from local Kondo screening to non-local singlet formation due to antiferromagnetic coupling as a function of separation of the cobalt atoms.Comment: 22 pages, 5 figure

Application of RAPD markers in hybrid verification in coconut

Abstract -Coconut palms are classified into two majo

Coherent Moving States in Highway Traffic (Originally: Moving Like a Solid Block)

Recent advances in multiagent simulations have made possible the study of realistic traffic patterns and allow to test theories based on driver behaviour. Such simulations also display various empirical features of traffic flows, and are used to design traffic controls that maximise the throughput of vehicles in heavily transited highways. In addition to its intrinsic economic value, vehicular traffic is of interest because it may throw light on some social phenomena where diverse individuals competitively try to maximise their own utilities under certain constraints. In this paper, we present simulation results that point to the existence of cooperative, coherent states arising from competitive interactions that lead to a new phenomenon in heterogeneous highway traffic. As the density of vehicles increases, their interactions cause a transition into a highly correlated state in which all vehicles practically move with the same speed, analogous to the motion of a solid block. This state is associated with a reduced lane changing rate and a safe, high and stable flow. It disappears as the vehicle density exceeds a critical value. The effect is observed in recent evaluations of Dutch traffic data.Comment: Submitted on April 21, 1998. For related work see http://www.theo2.physik.uni-stuttgart.de/helbing.html and http://www.parc.xerox.com/dynamics