The three gluon one particle irreducible function is investigated using lattice QCD simulations over a large region of momentum in the Landau gauge for four dimensional pure Yang-Mills equations and the SU(3) gauge group. The results favor a zero crossing of the gluon form factor for momenta in the range 220 − 260 MeV. This zero crossing is required to happen in order to have a properly defined set of Dyson-Schwinger equations. It is also shown that in the high momentum region the lattice results are compatible with the predictions of renormalisation group improved perturbation theory.The non-perturbative computation of the QCD Green's functions is an important step towards the understanding of the dynamics of strong interactions. The calculation of the Green's functions over the full momentum range is a non-trivial task, independently of taking into account or not the contribution of quarks. The lattice approach to QCD allows for first principles determination of the n-point complete Green functions as for example

The dependence of the Landau gauge two-point gluon and ghost correlation functions on the lattice spacing and on the physical volume are investigated for pure SU(3) Yang-Mills theory in four dimensions using lattice simulations. We present data from very large lattices up to 128 4 and for two lattice spacings 0.10 fm and 0.06 fm corresponding to volumes of ∼ð13 fmÞ 4 and ∼ð8 fmÞ 4 , respectively. Our results show that, for sufficiently large physical volumes, both propagators have a mild dependence on the lattice volume. On the other hand, the gluon and ghost propagators change with the lattice spacing a in the infrared region, with the gluon propagator having a stronger dependence on a compared to the ghost propagator. In what concerns the strong coupling constant α s ðp 2 Þ, as defined from gluon and ghost two-point functions, the simulations show a sizeable dependence on the lattice spacing for the infrared region and for momenta up to ∼1 GeV.

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Colonic intussusception is a rare cause of intestinal obstruction in adults and is caused by a malignant lesion in about 70% of cases. Early diagnosis and treatment are essential. We present a 64-year-old male patient with right colonic intussusception caused by a mixed adenoneuroendocrine carcinoma (MANEC), presenting as a giant pedunculated polyp (54 mm of largest diameter). The patient underwent right colectomy with primary anastomosis and adjuvant chemotherapy. The diagnosis of intussusception of the colon in adults is difficult because of its rarity and nonspecific clinical presentation. In this case, the cause was a rare histological type malignant tumor (MANEC).

The quenched gluon and ghost propagator data published in [Duarte et al. Phys. Rev. D 94, 014502 (2016).] is reanalyzed following the suggestion of [Boucaud et al. Phys. Rev. D 96, 098501 (2017).] to resolve the differences between the infrared data of the simulations. Our results confirm that the procedure works well either for the gluon or for the ghost propagator but not for both propagators simultaneously as the observed deviations in the data follow opposite patterns. Definitive conclusions require improving the determination of the (ratios) of lattice spacings. A simple procedure for the relative calibration of the lattice spacing in lattice simulations is suggested.

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This paper analyses the fundamentals of the Portuguese crisis. The financial crisis of 2007 worsened and triggered the current Portuguese crisis. We argue that the main problem the economy is facing is its output stagnation due to a kind of Dutch disease that has created high and increasing levels of indebtedness, low and decreasing levels of saving and has reduced Portuguese competitiveness. Moreover, the existence of a dualist labour market and a new wave of emigration produce inefficiency, increasing unemployment of younger workers and the supply of human capital abroad funded by the Portuguese taxpayers. Governance problems such as poor public budget governance and lack of transparency and accountability are also at stake. These governance problems must be solved to allow the economy to return to its long-run growth path

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.