Thermal monopoles and selfdual dyons in the Quark-Gluon Plasma

We perform a numerical study of the excess of non-abelian gauge invariant gluonic action around thermal abelian monopoles which populate the deconfined phase of Yang-Mills theories. Our results show that the excess of magnetic action is close to that of the electric one, so that thermal abelian monopoles may be associated with physical objects carrying both electric and magnetic charge, i.e. dyons. Thus, the quark gluon plasma is likely to be populated by selfdual dyons, which may manifest themselves in the heavy-ion collisions via the chiral magnetic effect. Thermodynamically, thermal monopoles provide a negative contribution to the pressure of the system.Comment: 9 pages, 4 figures, RevTeX 4.

The Lattice NJL Model at Non-zero Baryon and Isospin Densities

We present initial results of a numerical investigation of the chiral symmetry restoring transition in the (3+1)-dimensional Nambu -- Jona-Lasinio model with both non-zero baryon chemical potential (mu_B) and isospin chemical potential (mu_I). With non-zero isospin chemical potential, the model suffers from a sign problem. We proceed in two ways: (i) We perform ``partially quenched'' simulations in which mu_I is made non-zero only during the measurement of chiral observables; (ii) We perform full simulations with imaginary isospin chemical potential with the aim to analytically continue results to real mu_I.Comment: 3 pages, 3 figures, poster presented at LATTICE 2004, Fermi National Accelerator Laboratory, June 21-26, 200

Confinement and chiral symmetry breaking in heavy-light quark systems

Assuming a Gaussian approximation for the QCD gluodynamics, all the nonperturbative physics can be encoded into two parameters: the gluon correlation length $T_g$ and the gluon condensate $G_2$. These parameters are sufficient in order to describe the heavy-heavy quark nonperturbative interaction. In this work we adopt the same framework in order to study heavy-light bound states in the non-recoil limit. Spontaneous chiral symmetry breaking and a confining chiral non-invariant interaction emerge quite naturally. The gap equation is solved and discussed. In particular a relation between the light quark condensate and $T_g$ is derived. The energy spectrum for the bound state equation is evaluated and commented.Comment: 15 pages, 2 figures, elsart.st

Simultaneous sinus lift and implant placement using lateral approach in atrophic posterior maxilla with residual bone height of 5 mm or less. A systematic review

Aim To test both success and survival rate of implant placed simultaneously with sinus lift in atro-phic posterior maxilla with a residual bone height of less than 5 mm. Materials and methods A computer search strategy was developed for the following electronic databases: MEDLINE/ PubMed and EMBASE. All the relevant articles were screened involving controlled clinical trials, randomized clinical trials, prospective cohort studies. Results The selection process yielded 12 studies, published between 1999 and 2016, 6 of which were prospective, 1 was a randomized controlled trial, 5 were controlled studies. Conclusions Within the limitation of this systematic review, the qualitative data analysis revealed that the survival rate of implants placed in grafted sinus ranged from 61% to 100%; on the other hand, the success rate ranged between 75.3% to 94.8%. No significant differences were detected regarding different grafting materials used. In order to understand if the one-stage pro-cedure is an effective and predictable surgical alternative in critically resorbed maxillae, larger and well designed clinical trials are needed

The factorization method for systems with a complex action -a test in Random Matrix Theory for finite density QCD-

Monte Carlo simulations of systems with a complex action are known to be extremely difficult. A new approach to this problem based on a factorization property of distribution functions of observables has been proposed recently. The method can be applied to any system with a complex action, and it eliminates the so-called overlap problem completely. We test the new approach in a Random Matrix Theory for finite density QCD, where we are able to reproduce the exact results for the quark number density. The achieved system size is large enough to extract the thermodynamic limit. Our results provide a clear understanding of how the expected first order phase transition is induced by the imaginary part of the action.Comment: 27 pages, 25 figure

Bayesian Nonlocal Operator Regression (BNOR): A Data-Driven Learning Framework of Nonlocal Models with Uncertainty Quantification

We consider the problem of modeling heterogeneous materials where micro-scale dynamics and interactions affect global behavior. In the presence of heterogeneities in material microstructure it is often impractical, if not impossible, to provide quantitative characterization of material response. The goal of this work is to develop a Bayesian framework for uncertainty quantification (UQ) in material response prediction when using nonlocal models. Our approach combines the nonlocal operator regression (NOR) technique and Bayesian inference. Specifically, we use a Markov chain Monte Carlo (MCMC) method to sample the posterior probability distribution on parameters involved in the nonlocal constitutive law, and associated modeling discrepancies relative to higher fidelity computations. As an application, we consider the propagation of stress waves through a one-dimensional heterogeneous bar with randomly generated microstructure. Several numerical tests illustrate the construction, enabling UQ in nonlocal model predictions. Although nonlocal models have become popular means for homogenization, their statistical calibration with respect to high-fidelity models has not been presented before. This work is a first step towards statistical characterization of nonlocal model discrepancy in the context of homogenization

Tinnitus revival during COVID‑19 lockdown: how to deal with it?

To the Editor, The novel Coronavirus Disease, officially designated as COVID-19 by the WHO, is a serious issue for public health. To contain the COVID-19, the Italian Government stated on March 9th 2020 the prohibition of any movement throughout the national area unless for work/health reasons and the obligation to remain as much as possible inside one’s own home. With the start of the so-called “Phase Two” on May 4th 2020, circulation within the same region was allowed again, due to the progressive slowdown of the outbreak. Therefore, since lockdown measures were relaxed and access to the emergency room or ENT clinic became less worrying for patients, specialists of Otolaryngology Units in Bari (Italy) observed an increase in the amount of subjects complaining of the revival of intense tinnitus. We attempt in this letter to focus on patients affected by chronic subjective tinnitus, that already had a diagnosis and self-stabilized without a massive treatment. Research studies have reported tinnitus wide impact on quality of life of subjects experiencing it, involving their emotional state, concentration and sleep quality; at this regard, Tinnitus Handicap Inventory (THI) is a self-reported tool regularly used to quantify the grade of perceived handicap as slight (0–16), mild (18–36), moderate (38–56), severe (58–76) or catastrophic (78–100) on the basis of 25 questions [1]. During the past 2 weeks, we have collected data from 16 patients among our population of chronic sufferers: THI observed was moderate in 62.5% and severe in 18.75% of cases, catastrophic in 12.5% and mild in 6.25% of subjects. Interestingly, the grade of handicap resulted increased by one-level in 12 out of 16 patients (75%); in particular, THI shifted from mild to moderate in 9 patients and from moderate to severe in 3 patients. As shown in the literature, tinnitus generation, maintenance and recrudescence are still debated. A cortical reorganization secondary to sensory deprivation has been proposed as one on the most frequent cause of tinnitus [2]. The avoidance of silence and acoustic masking have been proposed as effective measures to overcome sensory deprivation and increase masking of the symptom [3]. It is reasonable to think that, during the lockdown, the absence of environmental masking sounds from everyday life may have enhanced the tinnitus perception. Furthermore, proneness to worry and incoming stress during pandemic could be included as further potential risk factors for tinnitus worsening. As proficiently reviewed in a recent work [4], some internet/smartphone-based applications provide in tinnitus patients adequate counseling and interactive information together with sound therapy. As brain networks implicated in adaptive responses to sound stimuli and to worry are shared in many cases, an early decrease of anxiety status may release neural resources crucial for tinnitus habituation/distress perception [5]. In general, interactive platforms have been widely implemented during lockdown period due to the forced lack of real personal and working relationships; since smart-working seems to be successful for future plans, the development of smart applications and mobile services in the health care field may be promising in terms of cost-effectiveness, tolerability and simplicity of use