Plaquette expectation value and lattice free energy of three-dimensional SU(N) gauge theory

We use high precision lattice simulations to calculate the plaquette expectation value in three-dimensional SU(N) gauge theory for N=2,3,4,5,8. Using these results, we study the N-dependence of the first non-perturbative coefficient in the weak-coupling expansion of hot QCD. We demonstrate that, in the limit of large N, the functional form of the plaquette expectation value with ultraviolet divergences subtracted is 15.9(2)-44(2)/N^2.Comment: 14 pages, 6 figures. v2: references added; published versio

Automatically generating Feynman rules for improved lattice field theories

Deriving the Feynman rules for lattice perturbation theory from actions and operators is complicated, especially when improvement terms are present. This physically important task is, however, suitable for automation. We describe a flexible algorithm for generating Feynman rules for a wide range of lattice field theories including gluons, relativistic fermions and heavy quarks. We also present an efficient implementation of this in a freely available, multi-platform programming language (\python), optimised to deal with a wide class of lattice field theories

Diagnosi e terapia chirurgica degli strumi mediastinici. Rilievi su 24 casi operati

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Individually Tailored Screening of Susceptibility to Sarcopenia Using p53 Codon 72 Polymorphism, Phenotypes, and Conventional Risk Factors

Background and Aim. p53 activity plays a role in muscle homeostasis and skeletal muscle differentiation; all pathways that lead to sarcopenia are related to p53 activities. We investigate the allelic frequency of the TP53 codon 72 in exon 4 polymorphism in the Italian female population and the association with appendicular skeletal muscle mass index in normal weight (NW), normal weight obese (NWO), and preobese-obese (Preob-Ob) subjects. Methods. We evaluated anthropometry, body composition, and p53 polymorphism in 140 women distinguished in NW, NWO, and Preob-Ob. Results. ∗Arg/∗Arg genotype increases sarcopenia risk up to 20% (∗Arg/∗Arg genotype OR = 1.20; 95% CI = 0.48–2.9; ∗proallele carriers OR = 0.83; 95% CI = 0.83–2.06). The risk of being sarcopenic for ∗Arg/∗Arg genotype in NWO and Preob-Ob is 31% higher than NW carriers of ∗proallele (RR = 0,31, 95% CI = 0,15–0,66, P = 0,0079). We developed a model able to predict sarcopenia risk based on age, body fat, and p53 polymorphism. Conclusion. Our study evidences that genotyping TP53 polymorphism could be a useful new genetic approach, in association with body composition evaluations, to assess sarcopenia risk

Effect of binary evolution on the inferred initial and final core masses of hydrogen-rich, Type II supernova progenitors

The majority of massive stars, which are the progenitors of core-collapse supernovae (SNe), are found in close binary systems. In a previous work, we modeled the fraction of hydrogen-rich, Type II SN progenitors whose evolution is affected by mass exchange with their companion, finding this to be between ≈1/3 and 1/2 for most assumptions. Here we study in more depth the impact of this binary history of Type II SN progenitors on their final pre-SN core mass distribution, using population synthesis simulations. We find that binary star progenitors of Type II SNe typically end their life with a larger core mass than they would have had if they had lived in isolation because they gained mass or merged with a companion before their explosion. The combination of the diverse binary evolutionary paths typically leads to a marginally shallower final core mass distribution. In discussing our results in the context of the red supergiant problem, that is, the reported lack of detected high luminosity progenitors, we conclude that binary evolution does not seem to significantly affect the issue. This conclusion is quite robust against our variations in the assumptions of binary physics. We also predict that inferring the initial masses of Type II SN progenitors by "age-dating"their surrounding environment systematically yields lower masses compared to methods that probe the pre-SN core mass or luminosity. A robust discrepancy between the inferred initial masses of a SN progenitor from those different techniques could indicate an evolutionary history of binary mass accretion or merging. © ESO 2020.Immediate accessThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Detection of non-Hodgkin's lymphoma liver disease in cirrhotic patients

Computer tomography (CT) scan and ultrasound scan (US) are the preferred methods for staging subdiaphragmatic non-Hodgkin’s lymphoma (NHL),1 but their sensitivity in detecting focal lesions in the liver may be reduced if fibrosis is present. We investigated 6 NHL patients who also had a viral liver disease (chronic active hepatitis or cirrhosis) by US and CT liver scans and liver biopsy. US was performed using a Spazio-Hitachi instrument with a 3.5 MHz probe. With the exception of two patients, who underwent laparotomy as a diagnostic procedure, liver biopsy was performed under US guidance using a Menghini fine needle with automatic aspiration (1.2 mm in diameter x 150 mm in length), or a Chiba fine needle (0.7 mm x 150 mm)

Binary-stripped Stars as Core-collapse Supernovae Progenitors

Most massive stars experience binary interactions in their lifetimes that can alter both the surface and core structure of the stripped star with significant effects on their ultimate fate as core-collapse supernovae. However, core-collapse supernovae simulations to date have focused almost exclusively on the evolution of single stars. We present a systematic simulation study of single and binary-stripped stars with the same initial mass as candidates for core-collapse supernovae (11–21 M⊙). Generally, we find that binary-stripped stars core tend to have a smaller compactness parameter, with a more prominent, deeper silicon/oxygen interface, and explode preferentially to the corresponding single stars of the same initial mass. Such a dichotomy of behavior between these two modes of evolution would have important implications for supernovae statistics, including the final neutron star masses, explosion energies, and nucleosynthetic yields. Binary-stripped remnants are also well poised to populate the possible mass gap between the heaviest neutron stars and the lightest black holes. Our work presents an improvement along two fronts, as we self-consistently account for the pre-collapse stellar evolution and the subsequent explosion outcome. Even so, our results emphasize the need for more detailed stellar evolutionary models to capture the sensitive nature of explosion outcome

Childhood obesity and skeletal-dental maturity

The aim of this cross-sectional study was to evaluate the skeletal maturation assessed through cervical vertebral maturation (CVM) and dental age, in normal weight, pre-obese and obese patients, using the Body Mass Index (BMI) and the Dual energy X-ray Absorptiometry (DXA)

High density QCD on a Lefschetz thimble?

It is sometimes speculated that the sign problem that afflicts many quantum field theories might be reduced or even eliminated by choosing an alternative domain of integration within a complexified extension of the path integral (in the spirit of the stationary phase integration method). In this paper we start to explore this possibility somewhat systematically. A first inspection reveals the presence of many difficulties but - quite surprisingly - most of them have an interesting solution. In particular, it is possible to regularize the lattice theory on a Lefschetz thimble, where the imaginary part of the action is constant and disappears from all observables. This regularization can be justified in terms of symmetries and perturbation theory. Moreover, it is possible to design a Monte Carlo algorithm that samples the configurations in the thimble. This is done by simulating, effectively, a five dimensional system. We describe the algorithm in detail and analyze its expected cost and stability. Unfortunately, the measure term also produces a phase which is not constant and it is currently very expensive to compute. This residual sign problem is expected to be much milder, as the dominant part of the integral is not affected, but we have still no convincing evidence of this. However, the main goal of this paper is to introduce a new approach to the sign problem, that seems to offer much room for improvements. An appealing feature of this approach is its generality. It is illustrated first in the simple case of a scalar field theory with chemical potential, and then extended to the more challenging case of QCD at finite baryonic density.Comment: Misleading footnote 1 corrected: locality deserves better investigations. Formula (31) corrected (we thank Giovanni Eruzzi for this observation). Note different title in journal versio