Kaons and pions in strange quark matter

The behavior of kaons and pions in strange quark matter in weak equilibrium, is investigated within the SU(3) Nambu-Jona-Lasinio [NJL] model. This work focuses a region of high densities where the behavior of mesons has not been explored in the framework of this model. It is found that above the density where strange valence quarks appear in the medium, $\rho = 3.8 \rho_0$, a change of behavior of different observables is observed indicating a tendency to the restoration of flavor symmetry. In particular, the splitting between charge multiplets, $K^+, K^-; K^0, {\bar K^0} {and} \pi^+, \pi^-$ decrease and the low energy modes with quantum numbers of $K^-, \bar K^0 {and} \pi^+$, which are excitations of the Fermi sea, are less relevant than for lower densities.Comment: 10 pages, 3 figures included; revised version, some changes in the discussio

Interplay between chiral and axial symmetries in a SU(2) Nambu--Jona-Lasinio Model with the Polyakov loop

We consider a two flavor Polyakov--Nambu--Jona-Lasinio (PNJL) model where the Lagrangian includes an interaction term that explicitly breaks the U$_A(1)$ anomaly. At finite temperature, the restoration of chiral and axial symmetries, signaled by the behavior of several observables, is investigated. We compare the effects of two regularizations at finite temperature, one of them, that allows high momentum quarks states, leading to the full recovery of chiral symmetry. From the analysis of the behavior of the topological susceptibility and of the mesonic masses of the axial partners, it is found in the SU(2) model that, unlike the SU(3) results, the recovery of the axial symmetry is not a consequence of the full recovery of the chiral symmetry. Thus, one needs to use an additional idea, by means of a temperature dependence of the anomaly coefficient, that simulates instanton suppression effects.Comment: 21 pages, 5 figures; PRD versio

Quality of Working Life and Employee Outcomes: A Literature Review

Quality of working life (QWL) is a research field studied since the 1970s, which has grown considerably since then (Grote & Guest, 2017). QWL covers an employee’s feelings about various dimensions of his or her work (Mosadeghrad, Ferlie & Rosenberg, 2011) and includes dimensions related with home-work interface, working condition, job and career satisfaction, control at work, stress at work, employee commitment and general well-being (Fontinha, Van Laar & Easton, 2016). At an individual level, positive outcomes of QWL include reduced absenteeism, lower turnover, improved job satisfaction, improved individual productivity (Mosadeghrad, Ferlie & Rosenberg, 2011), but studies that analyze, in a systematic way, all the employee outcomes associated to QWL are scarce. Following the systematic literature review (SLR) methodology, this article aims to identify the employee outcomes associated to the QWL construct. This article specifically explores research studies that have examined the QWL and consequences of it to individuals in a given organizational setting. Since our focus was to gain insight on the empirical investigation about QWL, we exclude studies with a primary focus on model development or testing measurement instruments. Extensive research has been performed at PROQUEST and EBSCO databases. The terms included the following on the title of the document: quality of life at work, work-related quality of life, quality of working life, working-life quality. Only the work-related consequences of QWL have been considered. The search has been limited to peer reviewed articles, theses, and conference papers published in the English language, between 1970 and 2017. The results show how a higher level of quality of life at work can improve several and relevant employee outcomes at work.CIEQV- Centro de Investigação em Qualidade de Vidainfo:eu-repo/semantics/publishedVersio

Anomalous decay of pion and eta at finite density

We study the anomalous decays $\pi^0, \eta \to\gamma\gamma$ in the framework of the three--flavor Nambu--Jona-Lasinio [NJL] model, in the vacuum and in quark matter in $\beta$ --equilibrium. It is found that the behavior of the relevant observables essentially reflects a manifestation of the partial restoration of chiral symmetry, in non strange and strange sectors. The probability of such decays decreases with density, showing that anomalous mesonic interactions are significantly affected by the medium.Comment: 12 pages, 4 figures included; revised version, to be published in Phys. Lett.

A case for including fiscal policies in the Eurostat Labour Market Policy database

In the context of the growing coordination of labour market policies (LMP) implementation within the European Employment Strategy (EES), the Eurostat offers a harmonised database that intends to be a valuable instrument for international comparisons in the field. However, because its tight scope fails to include some important LMP measures, this database has been playing a small role on studies related with the EES as well on those broadly focusing on labour market and employment policies. This paper intends to address, by using meaningful LMP measures - tax credits in the UK, the prime pour l'emploi and general reductions of employers’ social contributions in France -, the importance of having a more comprehensive database, while maintaining its current structure. For that we discuss the aims and the level of targeting defined by the Eurostat and we include, under this framework, an assessment of these measures to illustrate the limits of the database. We conclude that these policies - apparently fitting the broad objectives of the EES - are explicitly targeted to the labour market, aim at improving its efficiency and undoubtedly benefit particular groups. Moreover, they have an important impact in terms of participants and expenditure involved.European Employment Strategy; Eurostat Database; Active Labour Market Policies; Tax Credits; Reductions of Social Security Contributions.

Pseudoscalar neutral mesons in hot and dense matter

The behavior of neutral pseudoscalar mesons $\pi^0, \eta$ and $\eta'$ in hot and dense matter is investigated, in the framework of the three flavor Nambu-Jona-Lasinio model. Three different scenarios are considered: zero density and finite temperature, zero temperature and finite density in a flavor asymmetric medium with and without strange valence quarks, and finite temperature and density. The behavior of mesons is analyzed in connection with possible signatures of restoration of symmetries. In the high density region and at zero temperature it is found that the mass of the $\eta'$ increases, the deviation from the mass of the $\eta$ being more pronounced in matter without strange valence quarks.Comment: 10 pages, 4 figures included; revised version with one additional figure, some changes in the discussion, to be published in Phys. Lett.

η−η′\eta - \eta' in a hot and dense medium

The behavior of $\eta$ and $\eta'$ in hot strange quark matter in weak equilibrium with temperature, is investigated within the SU(3) Nambu-Jona-Lasinio [NJL] model. Possible manifestations of restoration of symmetries, by temperature or density, in the behavior of $\eta$ and $\eta'$ are discussed. The role played by the combined effect of temperature and density in the nature of the phase transition and meson behavior is also analyzed.Comment: 15 pages, 5 figures. Contribution to the Second International Workshop on Hadron Physics, Effective Theories of Low Energy QCD, 25-29 September, 2002 (Coimbra, Portugal