Gluon and Ghost Dynamics from Lattice QCD

The two point gluon and ghost correlation functions and the three gluon vertex are investigated, in the Landau gauge, using lattice simulations. For the two point functions, we discuss the approach to the continuum limit looking at the dependence on the lattice spacing and volume. The analytical structure of the propagators is also investigated by computing the corresponding spectral functions using an implementation of the Tikhonov regularisation to solve the integral equation. For the three point function we report results when the momentum of one of the gluon lines is set to zero and discuss its implications.Comment: Proceedings of Light Cone 2016, held in Lisbon, September 2016. Minor changes in text. To appear in Few B Sy

Liquid mixtures involving fluorinated alcohols: The equation of state (p, r, T, x) of (Ethanol + Trifluoroethanol) Experimental and Simulation

Liquid mixtures involving fluorinated alcohols: The equation of state (p, r, T, x) of (Ethanol + Trifluoroethanol) Experimental and Simulation Pedro Duartea, Djêide Rodriguesa, Marcelo Silvaa, Pedro Morgadoa, Luís Martinsa,b and Eduardo J. M. Filipea* aCentro de Química Estrutural, Instituto Superior Técnico, 1049-001 Lisboa, Portugal bCentro de Química de Évora, Universidade de Évora, 7000-671 Évora, Portugal Fluorinated alcohols are substances with unique properties and high technological value in the pharmaceutical and chemical industries. Trifluoroethanol (TFE), in particular, displays a number of unusual properties as a solvent. For example, it dissolves nylon at room temperature and is effectively used as solvent in bioengineering. The presence of the three fluorines atoms gives the alcohol a high ionization constant, strong hydrogen bonding capability and stability at high temperatures. In the pharmaceutical industry, TFE finds use as the major raw material for the production of inhalation anesthetics. Mixtures of TFE and water (known as Fluorinols®) are used as working fluids for Rankine cycle heat engines for terrestrial and space applications, as a result of a unique combination of physical and thermodynamic properties such as high thermal efficiency and excellent turbine expansion characteristics. Environmentally, TFE is a CFC substitute with an acceptable short lifetime and with small ozone depletion potential. Additionally, TFE is known to induce conformational changes in proteins and it is used as a co-solvent to analyze structural features of partially folded states. The (ethanol + TFE) system displays an interesting and peculiar behaviour, combining a negative azeotrope with high positive excess volumes. In this work, liquid mixtures of (ethanol + TFE) were investigated. The densities of the mixtures were measured as a function of composition between 278K and 338K and at pressures up to 700 bar. The corresponding excess volumes as a function of temperature and pressure, the isothermal compressibilities and thermal expansivities were calculated from the experimental results. The mixtures are highly non-ideal with excess volumes ranging from 0.8 - 1.0 cm3mol-1. Finally, molecular dynamic simulations were performed to model and interpret the experimental results. The Trappe force field was used to simulate the (TFE + ethanol) mixtures and calculate the corresponding excess volumes. The simulation results are able to reproduce the correct sign and order of magnitude of the experimental VE without fitting to the experimental data. Furthermore, the simulations suggest the presence of a particular type of hydrogen bridge between ethanol and TFE, that can help to rationalize the experimental results

Association between muscle strength and the\ud cardiopulmonary status of individuals living with\ud HIV/AIDS

OBJECTIVE: The purpose of this study was to compare aerobic function [anaerobic threshold (%_VVO2-AT),\ud respiratory compensation point (%_VVO2-RCP) and peak oxygen uptake (_VVO2peak)] between physically active patients\ud with HIV/AIDS and matched controls and to examine associations between disease status, poor muscle strength,\ud depression (as estimated by the profile of mood states questionnaire) and the aerobic performance of patients.\ud METHODS: Progressive treadmill test data for %_VVO2-AT (V-slope method), RCP and (_VVO2peak) were compared\ud between 39 male patients with HIV/AIDS (age 40.6¡1.4 years) and 28 male controls (age 44.4¡2.1 years) drawn\ud from the same community and matched for habitual physical activity. Within-patient data were also examined in\ud relation to CD4+ counts (nadir and current data) and peak isokinetic knee torque.\ud RESULTS: AT, RCP and (_VVO2peak) values were generally similar for patients and controls.Within the patient sample,\ud binary classification suggested that AT, RCP and (_VVO2peak) values were not associated with either the nadir or\ud current CD4+ count, but treadmill test variables were positively associated with peak isokinetic knee torque.\ud CONCLUSION: The aerobic performance of physically active patients with HIV/AIDS is generally well conserved.\ud Nevertheless, poor muscle strength is observed in some HIV/AIDS patients, which is associated with lower anaerobic\ud power and (_VVO2peak), suggesting the possibility of enhancing the aerobic performance of patients with weak\ud muscles through appropriate muscle-strengthening activities