Recent thermodynamic results from lattice QCD analyzed within a quasi-particle model

The thermodynamic behavior of QCD matter at high temperature is currently studied by lattice QCD theory. The main features are the fast rise of the energy density $\epsilon$ around the critical temperature $T_c$ and the large trace anomaly of the energy momentum tensor $< \Theta_\mu^\mu >=\epsilon - 3 P$ which hints at a strongly interacting system. Such features can be accounted for by employing a massive quasi-particle model with a temperature-dependent bag constant. Recent lattice QCD calculations with physical quark masses by the Wuppertal-Budapest group have shown a slower increase of $\epsilon$ and a smaller $<\Theta_\mu^\mu>$ peak with respect to previous results from the hotQCD collaboration. We investigate the implications of such differences from the point of view of a quasi-particle model, also discussing light and strange quark number susceptibilities. Furthermore, we predict the impact of these discrepancies on the temperature-dependence of the transport properties of matter, like the shear and bulk viscosities.Comment: 18 pages, 9 figures; version accepted in Phys. Rev.D; calculation with relaxation time \tau \sim g^4 ln g has been adde

Freeze-out conditions from net-proton and net-charge fluctuations at RHIC

We calculate ratios of higher-order susceptibilities quantifying fluctuations in the number of net protons and in the net-electric charge using the Hadron Resonance Gas (HRG) model. We take into account the effect of resonance decays, the kinematic acceptance cuts in rapidity, pseudo-rapidity and transverse momentum used in the experimental analysis, as well as a randomization of the isospin of nucleons in the hadronic phase. By comparing these results to the latest experimental data from the STAR collaboration, we determine the freeze-out conditions from net-electric charge and net-proton distributions and discuss their consistency.Comment: 7 pages, 6 figures, particle ratio figure adde

Perceived urban environment attributes and obesity indices in adults: an 8-nation study from Latin America

© The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.This study examines the associations between perceived urban environment attributes and obesity indices by country using data from an eight-nation study from Latin America. The data were collected from 8185 adults. The Neighbourhood Environment Walkability-abbreviated scale was used to assess perceived urban environment attributes. Obesity indices considered were body mass index, waist circumference, neck circumference, a body shape index and waist-to-height ratio. The perception of a more and better land use mix-diversity (β - 0.44; 95% CI - 0.59, - 0.28), traffic safety (- 0.39; - 0.66, - 0.12), and safety from crime (- 0.36; - 0.57, - 0.15) was associated with lower body mass index across the entire sample. Land use mix-diversity (- 1.21; - 1.60, - 0.82), street connectivity (- 0.26; - 0.37, - 0.15), and traffic safety (- 0.79; - 1.47, - 0.12) were negatively associated with waist circumference. Land use mix-diversity (- 0.11; - 0.20, - 0.03), land use mix-access (- 0.23; - 0.34, 0.12), walking/cycling facilities (- 0.22; - 0.37, - 0.08), and safety from crime (- 0.27; - 0.42, - 0.12) were negatively associated with neck circumference. No associations between perceived urban environment attributes and a body shape index were found. Land use mix-diversity (- 0.01; - 0.02, - 0.01), aesthetics (- 0.02; - 0.03, - 0.01), and safety from crime (- 0.02; - 0.04, - 0.01) were associated with waist-to-height ratio. Environmental interventions involving urban environment attributes are associated with obesity indices and, therefore, may help decrease the prevalence of overweight and obesity.info:eu-repo/semantics/publishedVersio