η\eta and η′\eta' mesons in nuclear matter and nuclei

We present updated and extended results for the $\eta$- and $\eta'$-nucleus bound state energies, obtained by solving the Schr\"{o}dinger and Klein-Gordon equations with complex optical potentials, for a wide range of nuclei. The $\eta$ and $\eta'$ nuclear potentials are obtained in the local density approximation from the mass shift of these mesons in nuclear matter, which is calculated within the quark-meson coupling model. Our results show that the $\eta$ and $\eta'$ mesons are expected to form mesic nuclei with all the nuclei considered. However, the signal for the formation of the $\eta$- and $\eta'$-mesic nuclei may be difficult to identify experimentally due to possible large widths.Comment: 11 pages, 4 figures, 6 table

The effective QCD phase diagram and the critical end point

We study the QCD phase diagram on the plane of temperature T and quark chemical potential mu, modelling the strong interactions with the linear sigma model coupled to quarks. The phase transition line is found from the effective potential at finite T and mu taking into accounts the plasma screening effects. We find the location of the critical end point (CEP) to be (mu^CEP/T_c,T^CEP/T_c) sim (1.2,0.8), where T_c is the (pseudo)critical temperature for the crossover phase transition at vanishing mu. This location lies within the region found by lattice inspired calculations. The results show that in the linear sigma model, the CEP's location in the phase diagram is expectedly determined solely through chiral symmetry breaking. The same is likely to be true for all other models which do not exhibit confinement, provided the proper treatment of the plasma infrared properties for the description of chiral symmetry restoration is implemented. Similarly, we also expect these corrections to be substantially relevant in the QCD phase diagram.Comment: 7 pages 3 figures; expanded discussion; added references; version to appear in Nucl. Phys.

Large-scale evaluation of shotgun triacylglycerol profiling for the fast detection of olive oil adulteration

Fast and effective analytical screening tools providing new suitable authenticity markers and applicable to a large number of samples are required to efficiently control the global olive oil (OO) production, and allow the rapid detection of low levels of adulterants even with fatty acid composition similar to OO. The present study aims to develop authentication models for the comprehensive detection of illegal blends of OO with adulterants including different types of high linoleic (HL) and high oleic (HO) vegetable oils at low concentrations (2–10%) based on shotgun triacylglycerol (TAG) profile obtained by Flow Injection Analysis-Heated Electrospray Ionisation-High Resolution Mass Spectrometry (FIA-HESI-HRMS) at a large-scale experimental design. The sample set covers a large natural variability of both OO and adulterants, resulting in more than one thousand samples analysed. A combined PLS-DA binary modelling based on shotgun TAG profiling proved to be a fit for purpose screening tool in terms of efficiency and applicability. The external validation resulted in the correct classification of the 86.8% of the adulterated samples (diagnostic sensitivity = 0.87), and the 81.1% of the genuine samples (diagnostic specificity = 0.81), with an 85.1% overall correct classification (efficiency = 0.85)

FAS system deregulation in T-cell lymphoblastic lymphoma

The acquisition of resistance towards FAS-mediated apoptosis may be required for tumor formation. Tumors from various histological origins exhibit FAS mutations, the most frequent being hematological malignancies. However, data regarding FAS mutations or FAS signaling alterations are still lacking in precursor T-cell lymphoblastic lymphomas (T-LBLs). The available data on acute lymphoblastic leukemia, of precursor origin as well, indicate a low frequency of FAS mutations but often report a serious reduction in FAS-mediated apoptosis as well as chemoresistance, thus suggesting the occurrence of mechanisms able to deregulate the FAS signaling pathway, different from FAS mutation. Our aim at this study was to determine whether FAS-mediated apoptotic signaling is compromised in human T-LBL samples and the mechanisms involved. This study on 26 T-LBL samples confirms that the FAS system is impaired to a wide extent in these tumors, with 57.7% of the cases presenting any alteration of the pathway. A variety of mechanisms seems to be involved in such alteration, in order of frequency the downregulation of FAS, the deregulation of other members of the pathway and the occurrence of mutations at FAS. Considering these results together, it seems plausible to think of a cumulative effect of several alterations in each T-LBL, which in turn may result in FAS/FASLG system deregulation. Since defective FAS signaling may render the T-LBL tumor cells resistant to apoptotic cell death, the correct prognosis, diagnosis and thus the success of anticancer therapy may require such an in-depth knowledge of the complete scenario of FAS-signaling alterations.S

Imaging dynamical chiral-symmetry breaking: pion wave function on the light front

We project onto the light front the pion's Poincaré-covariant Bethe-Salpeter wave function obtained using two different approximations to the kernels of quantum chromodynamics' Dyson-Schwinger equations. At an hadronic scale, both computed results are concave and significantly broader than the asymptotic distribution amplitude, φ(π)(asy)(x)=6x(1-x); e.g., the integral of φ(π)(x)/φ(π)(asy)(x) is 1.8 using the simplest kernel and 1.5 with the more sophisticated kernel. Independent of the kernels, the emergent phenomenon of dynamical chiral-symmetry breaking is responsible for hardening the amplitude.Lei Chang, I. C. Cloët, J. J. Cobos-Martinez, C. D. Roberts, S. M. Schmidt, and P. C. Tand