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We examine the dual graph representation of simplicial manifolds in Causal Dynamical Triangulations (CDT) as a mean to build observables, and propose a new representation based on the Finite Element Methods (FEM). In particular, with the application of FEM techniques, we extract the (low-lying) spectrum of the Laplace-Beltrami (LB) operator on the Sobolev space $H^1$ of scalar functions on piecewise flat manifolds, and compare them with corresponding results obtained by using the dual graph representation. We show that, besides for non-pathological cases in two dimensions, the dual graph spectrum and spectral dimension do not generally agree, neither quantitatively nor qualitatively, with the ones obtained from the LB operator on the continuous space. We analyze the reasons of this discrepancy and discuss its possible implications on the definition of generic observables built from the dual graph representation., 19 pages, 15 figures

39th International Symposium on Lattice Field Theory, Lattice 2022, Bonn, Germany, 8 Aug 2022 - 13 Aug 2022; Proceedings of Science / International School for Advanced Studies (LATTICE2022), 393 (2023). doi:10.22323/1.430.0393, We compute the topological susceptibility of $N_f = 2+1$ QCD at the physical point in a temperature range going from 200 to 600 MeV. We adopt a multicanonical approach to enhance topological fluctuations and a definition of the susceptibility based on the spectral projectors over the eigenmodes of the staggered Dirac operator. This method allows to reduce lattice artifacts affecting the standard gluonic definition, making the continuum limit extrapolation more reliable., Published by SISSA, Trieste

Journal of high energy physics 10(10), 197 (2022). doi:10.1007/JHEP10(2022)197, We compute the topological susceptibility of N$_{f}$ = 2 + 1 QCD with physical quark masses in the high-temperature phase, using numerical simulations of the theory discretized on a space-time lattice. More precisely we estimate the topological susceptibility for five temperatures in the range from ∼ 200 MeV up to ∼ 600 MeV, adopting the spectral projectors definition of the topological charge based on the staggered Dirac operator. This strategy turns out to be effective in reducing the large lattice artifacts which affect the standard gluonic definition, making it possible to perform a reliable continuum extrapolation. Our results for the susceptibility in the explored temperature range are found to be partially in tension with previous determinations in the literature., Published by SISSA, [Trieste]

We discuss the algorithmic problem of minimal coupling gauge fields of the Yang-Mills type to Quantum Gravity in the approach known as Causal Dynamical Triangulations (CDT) as a step towards studying, ultimately, systems of gravity coupled with bosonic and fermionic matter. We first describe the algorithm for general dimensions and gauge groups and then focus on the results obtained from simulations of 2d CDT coupled to gauge fields with U{(1)} and SU{(2)} gauge groups, where we studied both observables related to gravity and gauge fields, and compared them with analogous simulations in the static flat case., 12 pages, 6 figures; proceeding for the 38th International Symposium on Lattice Field Theory, LATTICE2021 26th-30th July, 2021 Zoom/Gather@Massachusetts Institute of Technology

Background: The gold standard to identify SARS-CoV-2 infections is the Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) on rhino-pharyngeal swabs, but faster and cheaper methods such as antigenic swabs have been developed. A retrospective observational study on antigenic swabs included in the extraordinary health surveillance protocol of a large Hospital in Turin was aimed to assess their performance validity. Methods: From 30 October 2020 to 4 May 2021, 4000 antigenic swabs were carried out in three groups of healthcare workers (HCWs), respectively (i) asymptomatic, (ii) cohabiting with a positive case, and (iii) not recently exposed to the virus. Results: Overall sensitivity and specificity associated with a prevalence of 1.30% were 26.9%, 97.2%, respectively, the corresponding positive (PPV) and negative predictive value (NPV) being 11.29% and 99.02% [95% IC (99.00 - 99.04)] respectively; a prevalence of 0.29% was observed in the asymptomatic group, among whom sensitivity and specificity were 25.0% and 98.9%, respectively, the corresponding PPV and NPV being 6.25% and 99.78% [95% IC (99.76 - 99.81)], respectively; the cohabitant group showed a prevalence of 21.11%, sensitivity and specificity were 47.4%, 81.7%, respectively, giving rise to a PPV of 40.91% and NPV of 85.29% [95% IC (85.18 – 85.41)] respectively. The prevalence in the not exposed group was 0.77%, sensitivity and specificity were 29.2%, 97.4%, respectively, and PPV and NPV 8.05% and 99.44% [95% IC (99.42 - 99.46)] respectively. Conclusions: Antigenic swabs reduced costs and provided reliable diagnostic results. In the cohabitant group, the higher-prevalence groups showed poor test performances, likely because of the high prevalence of pre-symptomatic illness in this group. Owing to the relatively low NPV, a negative result would still require confirmation with a molecular test to be acceptable for a surveillance program that effectively reduces the virus’s intra-hospital spread.

We discuss the discretization of Yang-Mills theories on Dynamical Triangulations in the compact formulation, with gauge fields living on the links of the dual graph associated with the triangulation, and the numerical investigation of the minimally coupled system by Monte Carlo simulations. We provide, in particular, an explicit construction and implementation of the Markov chain moves for 2D Causal Dynamical Triangulations coupled to either $U(1)$ or $SU(2)$ gauge fields; the results of exploratory numerical simulations on a toroidal geometry are also presented for both cases. We study the critical behavior of gravity related observables, determining the associated critical indices, which turn out to be independent of the bare gauge coupling: we obtain in particular $\nu = 0.496(7)$ for the critical index regulating the divergence of the correlation length of the volume profiles. Gauge observables are also investigated, including holonomies (torelons) and, for the $U(1)$ gauge theory, the winding number and the topological susceptibility. An interesting result is that the critical slowing down of the topological charge, which affects various lattice field theories in the continuum limit, seems to be strongly suppressed (i.e., by orders of magnitude) by the presence of a locally variable geometry: that may suggest possible ways for improvement also in other contexts., Comment: 13 pages, 14 figures

We illustrate the application of Quantum Computing techniques to the investigation of the thermodynamical properties of a simple system, made up of three quantum spins with frustrated pair interactions and affected by a hard sign problem when treated within classical computational schemes. We show how quantum algorithms completely solve the problem, and discuss how this can apply to more complex systems of physical interest, with emphasis on the possible systematics and on their control., 10 pages, 6 figures, QuBiPF collaboration

We show recent results of the application of spectral analysis in the setting of the Monte Carlo approach to Quantum Gravity known as Causal Dynamical Triangulations (CDT), discussing the behavior of the lowest lying eigenvalues of the Laplace-Beltrami operator computed on spatial slices. This kind of analysis provides information about running scales of the theory and about the critical behaviour around a possible second order transition in the CDT phase diagram, discussing the implications for the continuum limit., Comment: Proceeding of Science for parallel talk at the 37th International Symposium on Lattice Field Theory - Lattice2019, 16-22 June 2019, Wuhan, China

We extend the spectral projectors method to staggered fermions. Applying the index theorem to the staggered Dirac operator it is possible to work out an expression for the topological susceptibility which depends only on the orthogonal projectors on quasi zero-modes, as it has already been done for Dirac-Wilson fermions. Besides, we generalize this method deriving analogous expressions for all higher-order coefficients in the $\theta$-expansion of the vacuum energy., Comment: 7 pages, 3 figures; Proceedings of the 37th International Symposium on Lattice Field Theory - Lattice 2019, Wuhan (China)

The search for typical length scales, eventually diverging at a critical point, is a major goal for lattice approaches looking for a continuum theory of quantum gravity. Within the simplicial Monte Carlo approach known as causal dynamical triangulations, we study the spectrum of the Laplace operator to infer the geometrical properties of triangulations. In some phase of the theory a discrete set of length scales emerges, persisting in the infinite volume limit; such scales run as a function of the bare couplings, consistently with a critical behavior around a possible second order transition.

The spectral projectors method is a way to obtain a theoretically well posed definition of the topological susceptibility on the lattice. Up to now this method has been defined and applied only to Wilson fermions. The goal of this work is to extend the method to staggered fermions, giving a definition for the staggered topological susceptibility and testing it in the pure SU (3) gauge theory. Besides, we also generalize the method to higher-order cumulants of the topological charge distribution.

New archaeointensity results were obtained from 14 groups of baked-brick fragments collected in and around Pisa (Tuscany, Italy). The fragments were assembled from civil and religious buildings whose dating of construction or renovation, over the past millennium, was constrained by documentary sources. This collection, analysed using the Triaxe protocol, was found particularly suitable for intensity experiments, with a success rate of c. 84% corresponding to 276 fruitful specimens associated with 125 independent brick fragments. The Tuscan data clearly show a peak in intensity at the transition between the sixteenth and seventeenth centuries. They are also in very good agreement with, and complementary to, a dense dataset previously obtained in France. Considering the results available within a 700 km radius of Beaune (between Paris and Pisa), all satisfying a set of quality criteria, a mean geomagnetic field intensity variation curve was constructed for the past millennium using a newly developed transdimensional Bayesian technique. This curve, which thus incorporates the new Tuscan results, allows a better recognition of three intensity peaks (during the twelfth century, the fourteenth century and around AD 1600) in western Europe. The detail of this curve is a clear illustration of the centennial-scale resolution that can be achieved using accurate archaeointensity data.

// Antonino Tuttolomondo 1 , Claudia Colomba 2 , Danilo Di Bona 6 , Alessandra Casuccio 4 , Domenico Di Raimondo 1 , Giuseppe Clemente 1 , Valentina Arnao 5 , Rosaria Pecoraro 1 , Paolo Ragonese 5 , Anna Aiello 3 , Giulia Accardi 3 , Rosario Maugeri 5 , Carlo Maida 1 , Irene Simonetta 1 , Vittoriano Della Corte 1 , Domenico Gerardo Iacopino 5 , Calogero Caruso 3 , Antonio Cascio 2 and Antonio Pinto 1 on behalf of KIRIIND (KIR Infectious and Inflammatory Diseases) Collaborative Group 1 U.O.C di Medicina Interna con Stroke Care, Dipartimento Biomedico di Medicina Interna e Specialistica (Di.Bi.M.I.S), Universita degli Studi di Palermo, Palermo, Italy 2 U.O.C di Malattie Infettive, Dipartimento di Scienze per la Promozione della Salute e Materno Infantile G. D'Alessandro, Universita degli Studi di Palermo, Palermo, Italy 3 Dipartimento di Biopatologia e Biotecnologie Mediche, Universita degli Studi di Palermo, Palermo, Italy 4 Dipartimento di Scienze per la Promozione della Salute e Materno Infantile “G. D'Alessandro”, Universita degli Studi di Palermo, Palermo, Italy 5 Dipartimento di BioMedicina Sperimentale e Neuroscienze Cliniche, Universita degli Studi di Palermo, Palermo, Italy 6 School of Allergology, Dipartimento delle Emergenze e Trapianti d'Organo, University of Bari, Bari, Italy Correspondence to: Antonino Tuttolomondo, email: bruno.tuttolomondo@unipa.it Keywords: KIRs; HLA; encephalitis Received: December 11, 2017 Accepted: February 25, 2018 Published: April 03, 2018 ABSTRACT Introduction: The HLA genes, as well as the innate immune KIR genes, are considered relevant determinants of viral outcomes but no study, to our knowledge, has evaluated their role in the clinical setting of acute viral encephalitis. Results: Subjects with acute viral encephalitis in comparison to subjects without acute viral encephalitis showed a significantly higher frequency of 2DL1 KIR gene and AA KIR haplotypes and of HLA-C2 and HLA-A-Bw4 alleles. Subjects without acute viral encephalitis showed a higher frequency of interaction between KIR2DL2 and HLAC1. Multiple logistic regression analysis showed the detrimental effect of HLA-A haplotype and HLA-C1, HLA-A-BW4 HLA-B-BW4 T alleles, whereas multiple logistic regression showed a protective effect of AB+BB KIR haplotype and a detrimental effect of interaction between KIR3DL1 and HLA-A-Bw4. Discussion: Our findings of a lower frequency of activating receptors in patients with acute encephalitis compared to controls could result in a less efficient response of NK cells. This finding could represent a possible pathogenetic explanation of susceptibility to acute symptomatic encephalitis in patients with viral infection from potentially responsible viruses such as Herpes virus. Materials and Methods: 30 Consecutive patients with symptomatic acute viral encephalitis and as controls, 36 consecutive subjects without acute encephalitis were analyzed. The following KIR genes were analyzed, KIR2DL1, 2DL2, 2DL3, 2DL5, 3DL1, 3DL2, 3DL3, 2DL4, 2DS1, 2DS2, 2DS3, 2DS4, 2DS5, 3DS1, 2 pseudogenes (2DP1 and 3DP1) and the common variants of KIR2DL5 (KIR2DL5A, KIR2DL5B).

We propose a new method to characterize the different phases observed in the non-perturbative numerical approach to quantum gravity known as Causal Dynamical Triangulation. The method is based on the analysis of the eigenvalues and the eigenvectors of the Laplace-Beltrami operator computed on the triangulations: it generalizes previous works based on the analysis of diffusive processes and proves capable of providing more detailed information on the geometric properties of the triangulations. In particular, we apply the method to the analysis of spatial slices, showing that the different phases can be characterized by a new order parameter related to the presence or absence of a gap in the spectrum of the Laplace-Beltrami operator, and deriving an effective dimensionality of the slices at the different scales. We also propose quantities derived from the spectrum that could be used to monitor the running to the continuum limit around a suitable critical point in the phase diagram, if any is found., Comment: 21 pages, 26 figures, 2 tables

Introduction Patients with chronic liver diseases are usually thin as a result of hypermetabolism and malnutrition expressed by reduced levels of leptin and impairment of other adyponectins such as visfatin. Aims We evaluated the metabolic and inflammatory effects of intravenous high-dose furosemide plus hypertonic saline solutions (HSS) compared with repeated paracentesis and a standard oral diuretic schedule, in patients with cirrhosis and refractory ascites. Methods 59 consecutive cirrhotic patients with refractory ascites unresponsive to outpatient treatment. Enrolled subjects were randomized to treatment with intravenous infusion of furosemide (125-250mg⁄bid) plus small volumes of HSS from the first day after admission until 3 days before discharge (Group A, n:38), or repeated paracentesis from the first day after admission until 3 days before discharge (Group B, n: 21). Plasma levels of ANP, BNP, Leptin, visfatin, IL-1β, TNF-a, IL-6 were measured before and after the two type of treatment. Results Subjects in group A were observed to have a significant reduction of serum levels of TNF-α, IL-1β, IL-6, ANP, BNP, and visfatin, thus regarding primary efficacy endpoints, in Group A vs. Group B we observed higher Δ-TNF-α, Δ-IL-1β, Δ-IL-6, Δ-ANP, Δ-BNP, Δ-visfatin, Δ-Leptin at discharge. Discussion Our findings underline the possible inflammatory and metabolic effect of saline overload correction in treatment of cirrhosis complications such as refractory ascites, suggesting a possible role of inflammatory and metabolic-nutritional variables as severity markers in these patients.

A 59-year-old nursing home patient with Down syndrome was brought to the internal medicine department of our hospital due to fever, cough without expectorate, and dyspnea. A thoracic computed tomography revealed the presence of bilateral basal parenchymal opacities. Her condition deteriorated after admission and troponin reached a peak serum concentration of 16.9 ng/mL. The patient was in cardiogenic shock. In addition to fluid resuscitation, vaso-active amine infusion was administered to achieve hemodynamic stabilization. The differential diagnosis investigated possible pulmonary embolism, myocardial infarction, and myocarditis. Furthermore, a second transthoracic echocardiogram suggested Tako-Tsubo syndrome. This is a septic patient. The purpose of this manuscript is to review studies which formerly examined the possible association between high levels of troponin and mortality to see if it can be considered a positive predictive factor of fatal prognosis as the case of thrombocytopenia, already a positive independent predictive factor of multiple organ failure syndrome, and generally to characterize risk profile in a septic patient.

CD4+ CD28− T cells also called CD28 null cells have been reported as increased in the clinical setting of acute coronary syndrome. Only 2 studies previously analyzed peripheral frequency of CD28 null cells in subjects with acute ischemic stroke but, to our knowledge, peripheral frequency of CD28 null cells in each TOAST subtype of ischemic stroke has never been evaluated. We hypothesized that CD4+ cells and, in particular, the CD28 null cell subset could show a different degree of peripheral percentage in subjects with acute ischemic stroke in relation to clinical subtype and severity of ischemic stroke. The aim of our study was to analyze peripheral frequency of CD28 null cells in subjects with acute ischemic stroke in relation to TOAST diagnostic subtype, and to evaluate their relationship with scores of clinical severity of acute ischemic stroke, and their predictive role in the diagnosis of acute ischemic stroke and diagnostic subtype We enrolled 98 consecutive subjects admitted to our recruitment wards with a diagnosis of ischemic stroke. As controls we enrolled 66 hospitalized patients without a diagnosis of acute ischemic stroke. Peripheral frequency of CD4+ and CD28 null cells has been evaluated with a FACS Calibur flow cytometer. Subjects with acute ischemic stroke had a significantly higher peripheral frequency of CD4+ cells and CD28 null cells compared to control subjects without acute ischemic stroke. Subjects with cardioembolic stroke had a significantly higher peripheral frequency of CD4+ cells and CD28 null cells compared to subjects with other TOAST subtypes. We observed a significant relationship between CD28 null cells peripheral percentage and Scandinavian Stroke Scale and NIHSS scores. ROC curve analysis showed that CD28 null cell percentage may be useful to differentiate between stroke subtypes. These findings seem suggest a possible role for a T-cell component also in acute ischemic stroke clinical setting showing a different peripheral frequency of CD28 null cells in relation of each TOAST subtype of stroke.

Thrombotic strokes can affect large or small arteries in the brain. Drugs to prevent atherosclerosis complication such as thrombotic strokes, should be drugs able to prevent the accumulation of intravascular fat, reduce vascular proliferation, decrease blood pressure levels with the resulting shear stress, reduce platelet aggregation, and possibly partially or totally reverse carotid plaques. Any of the commonly used antihypertensive drugs lower the incidence of stroke, with larger reductions in BP resulting in larger reductions in risk. Experimental and clinical data suggest that reducing the activity of the renin-angiotensin aldosterone system (RAAS) may have beneficial effects beyond the lowering of blood pressure to reduce stroke incidence. In clinical trials, statins consistently reduced the risk of ischemic stroke in patients with or without CHD whereas the data on the effects of other lipid modifying drugs on stroke risk are limited. Approximately 25% of strokes are recurrent. Antiplatelet therapy is indicated for the prevention of recurrent stroke in patients with a history of noncardioembolic minor stroke or transient ischemic attack (TIA). Although clinicians may choose acetylsalicylic acid (ASA) as first-line therapy for secondary prevention, clinical guidelines and evidence from trials suggest that ASA may not be the most effective strategy. A recent review discussed results from clinical trials that have compared the efficacy of ASA monotherapy versus ASA + extended release dipyridamole in secondary stroke prevention. Therefore it is difficult to extrapolate the real benefit of pharmacological prevention strategies against atherothrombotic subtype for excellence in the TOAST classification subtype that is represented by the LAAS and also with regard to lacunar subtype as an expression of lipohyalinosis process which is a further aspect of atherosclerosis.

Background The genetic basis of complex diseases like ischemic stroke probably consists of several predisposing risk factors, such as genes involved in inflammation and thrombotic pathways. On this basis the aim of our study was to evaluate the role of SNPs (single nucleotide polymorphisms) of some pro-inflammatory/anti-inflammatory and coagulation/fibrinolytic genes in patients with acute ischemic stroke. Methods The study population consisted of 144 consecutive Caucasian adult patients who were hospitalized in the Internal Medicine Department at the University of Palermo between November 2006 and January 2008, and who met inclusion criteria. The cases were patients admitted with a diagnosis of acute ischemic stroke, and age-matched (±3 years) control subjects: patients admitted to our Internal Medicine Department for any cause other than acute cardiovascular and cerebrovascular events and for routine checkup examinations. Molecular analysis of alleles at the −308 nucleotide (−308G/A) of TNF-α gene, −1082/−819 haplotypes of IL-10 gene, IL-1RN exon 2 VNR polymorphism, alleles at the −174 nucleotide (−174G/C) of IL-6 gene, PAI-1675 5G/4G polymorphism, alleles at the −7351 nucleotide (−7351C/T) of tPA gene was undertaken in both patient groups. Results We analyzed 96 subjects with acute ischemic stroke and 48 control subjects. We observed a significantly higher frequency of IL-10 1082 AA genotype in stroke patients with a significant risk trend. We also reported a higher frequency in stroke subjects with a significant risk trend of the TPA 7351-CT genotype and of IL-1RN-VNTR 86 bp 2/2 genotype. Moreover, we observed a significant relationship with TOAST subtype only with regard to CC TPA genotype and 1/1 IL-1 VNTR 86 bp and lacunar strokes . Conclusions Ischemic stroke is a common multifactor disease, which is affected by a number of genetic mutations and environmental factors. Our findings showing a relationship between pro-inflammatory/anti-inflammatory and thrombotic/fibrinolytic genes SNPs and ischemic stroke may contribute to delineate a possible stroke risk profile in subjects with cerebrovascular risk factors.