University of Mons

About: University of Mons is a education organization based out in Mons, Belgium. It is known for research contribution in the topics: Large Hadron Collider & Standard Model. The organization has 3073 authors who have published 9465 publications receiving 294776 citations.

Modeling of CW Yb-doped fiber lasers with highly nonlinear cavity dynamics.

Abstract: We develop a theoretical framework for modeling of continuous wave Yb-doped fiber lasers with highly nonlinear cavity dynamics. The developed approach has shown good agreement between theoretical predictions and experimental results for particular scheme of Yb-doped laser with large spectral broadening during single round trip. The model is capable to accurately describe main features of the experimentally measured laser outputs such as power efficiency slope, power leakage through fibre Bragg gratings, spectral broadening and spectral shape of generated radiation.

Six month follow-up of self-reported loss of smell during the COVID-19 pandemic.

Abstract: INTRODUCTION: Loss of smell and taste is now recognised as amongst the most common symptoms of COVID-19 and the best predictor of COVID-19 positivity. Long term outcomes are unknown. This study aims to investigate recovery of loss of smell and the prevalence of parosmia. METHODOLOGY: 6-month follow-up of respondents to an online surgery who self-reported loss of smell at the onset of the CO- VID-19 pandemic in the UK. Information of additional symptoms, recovery of loss of smell and the development of parosmia was collected. RESULTS: 44% of respondents reported at least one other ongoing symptom at 6 months, of which fatigue (n=106) was the most prevalent. There was a significant improvement in self-rating of severity of olfactory loss where 177 patients stated they had a normal smell of smell while 12 patients reported complete loss of smell. The prevalence of parosmia is 43.1% with median interval of 2.5 months (range 0-6) from the onset of loss of smell. CONCLUSIONS: While many patients recover quickly, some experience long-term deficits with no self-reported improvement at 6 months. Furthermore, there is a high prevalence of parosmia even in those who report at least some recovery of olfactory func- tion. Longer term evaluation of recovery is required.

Protein corona affects the relaxivity and MRI contrast efficiency of magnetic nanoparticles

Abstract: Magnetic nanoparticles (NPs) are increasingly being considered for use in biomedical applications such as biosensors, imaging contrast agents and drug delivery vehicles. In a biological fluid, proteins associate in a preferential manner with NPs. The small sizes and high curvature angles of NPs influence the types and amounts of proteins present on their surfaces. This differential display of proteins bound to the surface of NPs can influence the tissue distribution, cellular uptake and biological effects of NPs. To date, the effects of adsorption of a protein corona (PC) on the magnetic properties of NPs have not been considered, despite the fact that some of their potential applications require their use in human blood. Here, to investigate the effects of a PC (using fetal bovine serum) on the MRI contrast efficiency of superparamagnetic iron oxide NPs (SPIONs), we have synthesized two series of SPIONs with variation in the thickness and functional groups (i.e. surface charges) of the dextran surface coating. We have observed that different physico-chemical characteristics of the dextran coatings on the SPIONs lead to the formation of PCs of different compositions. 1H relaxometry was used to obtain the longitudinal, r1, and transverse, r2, relaxivities of the SPIONs without and with a PC, as a function of the Larmor frequency. The transverse relaxivity, which determines the efficiency of negative contrast agents (CAs), is very much dependent on the functional group and the surface charge of the SPIONs' coating. The presence of the PC did not alter the relaxivity of plain SPIONs, while it slightly increased the relaxivity of the negatively charged SPIONs and dramatically decreased the relaxivity of the positively charged ones, which was coupled with particle agglomeration in the presence of the proteins. To confirm the effect of the PC on the MRI contrast efficiency, in vitro MRI experiments at ν = 8.5 MHz were performed using a low-field MRI scanner. The MRI contrasts, produced by different samples, were fully in agreement with the relaxometry findings.

J/ψ and ψ (2S) production in pp collisions at √s = 7 TeV

Abstract: A measurement of the J/psi and psi(2S) production cross sections in pp collisions at sqrt(s)=7 TeV with the CMS experiment at the LHC is presented. The data sample corresponds to an integrated luminosity of 37 inverse picobarns. Using a fit to the invariant mass and decay length distributions, production cross sections have been measured separately for prompt and non-prompt charmonium states, as a function of the meson transverse momentum in several rapidity ranges. In addition, cross sections restricted to the acceptance of the CMS detector are given, which are not affected by the polarization of the charmonium states. The ratio of the differential production cross sections of the two states, where systematic uncertainties largely cancel, is also determined. The branching fraction of the inclusive B to psi(2S) X decay is extracted from the ratio of the non-prompt cross sections to be: BR(B to psi(2S) X) = (3.08 +/- 0.12(stat.+syst.) +/- 0.13(theor.) +/- 0.42(BR[PDG])) 10^-3