0000000000134899

AUTHOR

Francesco Romeo

Time evolution of non-lethal infectious diseases: a semi-continuous approach.

A model describing the dynamics related to the spreading of non-lethal infectious diseases in a fixed-size population is proposed. The model consists of a non-linear delay-differential equation describing the time evolution of the increment in the number of infectious individuals and depends upon a limited number of parameters. Predictions are in good qualitative agreement with data on influenza.

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Incidence, determinants and prognostic relevance of dyspnea at admission in patients with Takotsubo syndrome: results from the international multicenter GEIST registry

AbstractClinical presentation of Takotsubo syndrome (TTS) may range from acute chest pain to dyspnea: the prognostic role of clinical onset is still controversial. Aim of this study was therefore to investigate the prognostic relevance of dyspnea at presentation in patients with TTS. We analyzed 1,071 TTS patients (median age 72 years, 90% female) enrolled in the international multicenter GEIST registry. Patients were divided according to the presence or absence of dyspnea at hospital admission, as clinically assessed by the accepting physician. The primary endpoint was occurrence of in-hospital complications defined as a composite of pulmonary edema, cardiogenic shock and death. Overall, 3…

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Coronavirus disease 2019 infection and the cardiovascular system

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Dietary intake and major food sources of polyphenols in people with type 2 diabetes: The TOSCA.IT Study

Purpose: Proper evaluation of polyphenols intake at the population level is a necessary step in order to establish possible associations with health outcomes. Available data are limited, and so far no study has been performed in people with diabetes. The aim of this work was to document the intake of polyphenols and their major food sources in a cohort of people with type 2 diabetes and in socio-demographic subgroups. Methods: We studied 2573 men and women aged 50–75 years. Among others, anthropometry was measured by standard protocol and dietary habits were investigated by food frequency questionnaire (EPIC). The intake of polyphenols was evaluated using US Department of Agriculture and Ph…

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Rashba spin-orbit-interaction-based quantum pump in graphene

We present a proposal for an adiabatic quantum pump based on a graphene monolayer patterned by electrostatic gates and operated in the low-energy Dirac regime. The setup under investigation works in the presence of inhomogeneous spin-orbit interactions of intrinsic- and Rashba-type and allows to generate spin polarized coherent current. A local spin polarized current is induced by the pumping mechanism assisted by the spin-double refraction phenomenon.

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Adiabatic quantum pumping, magnification effects and quantum size effects of spin-torque in magnetic tunnel junctions

We study the adiabatic quantum pumping and quantum size effects of spin-torque in a magnetic tunnel junction within a scattering matrix approach. Quantum size effects are predicted in the presence of a dc bias as a function of the thickness of the normal metal layer inserted between two magnetic layers and of the fixed magnetic layer. In the presence of ac voltages, the results for the spin-torque show a peculiar magnification effect and advantages of spin-torque pumping in actual devices are also discussed.

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An expression of concern on research during the Covid-19 pandemic

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Valley to charge current conversion in graphene grain boundaries

The conduction properties of a grain boundary junction with Fermi velocity mismatch are analyzed. We provide a generalization of the Dirac Hamiltonian model taking into account the Fermi velocity gradient at the interface. General boundary conditions for the scattering problem are derived within the framework of the matching matrix method. We show that the scattering properties of the interface, as predicted by the theory, strongly depend on the boundary conditions used. We demonstrate that when the valley degeneracy is broken a charge current is established at the grain boundary interface. These findings provide the working principle of a valley to charge current converter, which is releva…

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Persistent spin and charge currents and magnification effects in open ring conductors subject toRashba coupling

We analyze the effect of Rashba spin-orbit coupling and of a local tunnel barrier on the persistent spin and charge currents in a one-dimensional conducting Aharonov-Bohm (AB) ring symmetrically coupled to two leads. First, as an important consequence of the spin-splitting, it is found that a persistent spin current can be induced which is not simply proportional to the charge current. Second, a magnification effect of the persistent spin current is shown when one tunes the Fermi energy near the Fano-type antiresonances of the total transmission coefficient governed by the tunnel barrier strength. As an unambiguous signature of spin-orbit coupling we also show the possibility to produce a p…

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Number theory implications on the physical properties of elementary cubic networks of Josephson junctions

Number theory concepts are used to investigate the periodicity properties of the voltage vs applied flux curves of elementary cubic networks of Josephson junctions. It is found that equatorial gaps appearing on the unitary sphere, on which points representing the directions in space for which these curves show periodicity are collected, can be understood by means of Gauss condition on the sum of the squares of three integers.

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Incidence and Clinical Impact of Recurrent Takotsubo Syndrome: Results From the GEIST Registry

Background Current literature only reports variable information from single‐center studies on the recurrence rate, the complications, and the outcome of patients with Takotsubo syndrome ( TTS) experiencing recurrent TTS . Therefore, a detailed description of clinical characteristics, predictors, and the prognostic impact of patients with TTS and recurrences in a multicenter registry is needed. Methods and Results We analyzed 749 patients with TTS from 9 European centers being part of the international, multicenter GEIST (German Italian Stress Cardiomyopathy) Registry. Patients were divided into the recurrence group and the nonrecurrence group. The recurrence rate at a median follow‐up of 8…

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Unveiling signatures of topological phases in open kitaev chains and ladders

In this work, the general problem of the characterization of the topological phase of an open quantum system is addressed. In particular, we study the topological properties of Kitaev chains and ladders under the perturbing effect of a current flux injected into the system using an external normal lead and derived from it via a superconducting electrode. After discussing the topological phase diagram of the isolated systems, using a scattering technique within the Bogoliubov de Gennes formulation, we analyze the differential conductance properties of these topological devices as a function of all relevant model parameters. The relevant problem of implementing local spectroscopic measurement…

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Climatic variables in Takotsubo cardiomyopathy: role of temperature

Background Recent studies documented a seasonal (summer) and circadian (morning) temporal distribution of takotsubo cardiomyopathy (TTC). Aim The aim of our study was to investigate whether there is a relationship among season, temperature and the occurrence of TTC. A second aim of our study was the comparison of climatic variables in Takotsubo cardiomyopathy versus acute myocardial infarction (AMI). Methods We enrolled consecutive patients with TTC in three Italian centres and, for comparison consecutive patients with AMI. The frequency of TTC and AMI patients according to month, season and quartiles of temperature (I quartile: 9.8–15-, II quartile: 15–19-, III quartile: 19–25- and IV quar…

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Effect of Confinement and Coulomb Interactions on the Electronic Structure of the (111) LaAlO3/SrTiO3 Interface

A tight binding supercell approach is used for the calculation of the electronic structure of the (111) LaAlO3/SrTiO3 interface. The confinement potential at the interface is evaluated solving a discrete Poisson equation by means of an iterative method. In addition to the effect of the confinement, local Hubbard electron–electron terms are included at the mean-field level within a fully self-consistent procedure. The calculation carefully describes how the two-dimensional electron gas arises from the quantum confinement of electrons near the interface due to the band bending potential. The resulting electronic sub-bands and Fermi surfaces show full agreement with the electronic structure de…

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ANMCO/ISS/AMD/ANCE/ARCA/FADOI/GICR-IACPR/SICI-GISE/SIBioC/SIC/SICOA/SID/SIF/SIMEU/SIMG/SIMI/SISA Joint Consensus Document on cholesterol and cardiovascular risk: diagnostic–therapeutic pathway in Italy

Atherosclerotic cardiovascular disease still represents the leading cause of death in western countries. A wealth of scientific evidence demonstrates that increased blood cholesterol levels have a major impact on the outbreak and progression of atherosclerotic plaques. Moreover, several cholesterol-lowering pharmacological agents, including statins and ezetimibe, have proven effective in improving clinical outcomes. This document is focused on the clinical management of hypercholesterolemia and has been conceived by 16 Italian medical associations with the support of the Italian National Institute of Health. The authors have considered with particular attention the role of hypercholesterole…

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Prevalence, management, and outcome of adverse rhythm disorders in takotsubo syndrome: insights from the international multicenter GEIST registry

One important complication related to takotsubo syndrome (TTS) is adverse rhythm disorders. Our study was conducted to determine the incidence and management of adverse rhythm disorders in TTS and its long-term prognostic impact. We analyzed 906 TTS patients from 9 European centers. Patients were divided into the adverse rhythm disorders group (encompassing ventricular tachycardia, ventricular fibrillation, torsade de pointes, and asystole or complete atrioventricular block) and non-adverse rhythm disorders group. In our study cohort, we identified 67 (7.4%) patients with presence of adverse rhythm disorders. TTS patients were followed up over a period of 2.8 years. In the adverse rhythm di…

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Spin current pumping in helical Luttinger liquids

We study the DC spin current induced into an unbiased quantum spin Hall system through a two-point contacts setup with time dependent electron tunneling amplitudes. By means of two external gates, it is possible to drive a current with spin-preserving and spin-flipping contributions showing peculiar oscillations as a function of pumping frequency, electron-electron interaction and temperature. From its interference patterns as a function of the Fabry-Perot and Aharonov-Bohm phases, it is possible to extract information about the helical nature of the edge states and the intensity of the electron-electron interaction.

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Search forBs0→μ+μ−andB0→μ+μ−Decays with CDF II

A search has been performed for B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} and B{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays using 7 fb{sup -1} of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. The observed number of B{sup 0} candidates is consistent with background-only expectations and yields an upper limit on the branching fraction of {Beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 6.0 x 10{sup -9} at 95% confidence level. We observe an excess of B{sub s}{sup 0} candidates. The probability that the background processes alone could produce such an excess or larger is 0.27%. The probability that the combination of background and the expe…

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Electrically Controlled Pumping of Spin Currents in Topological Insulators

Pure spin currents are shown to be generated by an electrically controlled quantum pump applied at the edges of a topological insulator. The electric rather than the more conventional magnetic control offers several advantages and avoids, in particular, the necessity of delicate control of magnetization dynamics over tiny regions. The pump is implemented by pinching the sample at two quantum point contacts and phase modulating two external gate voltages between them. The spin current is generated for the full range of parameters. On the other hand, pumping via amplitude modulation of the inter-boundary couplings generates both charge and spin currents, with a pure charge current appearing o…

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Pulmonary hypertension in pediatrics. a feasible approach to bridge the gap between real world and guidelines

Pulmonary hypertension (PH) is quite infrequent in pediatric age and its most common etiologies include idiopathic pulmonary arterial hypertension, PH related to congenital heart diseases, bronchopulmonary dysplasia (chronic lung disease), persistence of pulmonary hypertension of the newborn, and congenital diaphragmatic hernia. The developed for adult patients PH classification shows limitations when applied to pediatric subjects since the underlying causes are markedly different between the two ages. In 2011, the Pulmonary Vascular Research Institute Panama Task Force outlined the first specific pediatric pulmonary hypertensive vascular disease diagnostic classification, including 10 main…

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Prevalence and Prognostic Impact of Diabetes in Takotsubo Syndrome: Insights From the International, Multicenter GEIST Registry

OBJECTIVE In view of low prevalence rates, diabetes is discussed as a protective factor for the occurrence of Takotsubo syndrome (TTS). Furthermore, it was associated with improved outcome in a small single-center analysis. Therefore, this study assessed the prevalence and prognostic relevance of concomitant diabetes in TTS. RESEARCH DESIGN AND METHODS A total of 826 patients with TTS were enrolled in an international, multicenter, registry-based study (eight centers in Italy and Germany). All-cause mortality was compared between patients with diabetes and patients without diabetes, and the independent predictive value of diabetes was evaluated in multivariate regression analysis. RESULTS …

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Effect of confinement and Coulomb interactions on the electronic structure of (111) LaAlO$_3$/SrTiO$_3$ interface

A tight binding supercell approach is used for the calculation of the electronic structure of the (111) LaAlO$_3$/SrTiO$_3$ interface. The confinement potential at the interface is evaluated solving a discrete Poisson equation by means of an iterative method. In addition to the effect of the confinement, local Hubbard electron-electron terms are included at mean-field level within a fully self-consistent procedure. The calculation carefully describes how the two-dimensional electron gas arises from the quantum confinement of electrons near the interface due to band bending potential. The resulting electronic sub-bands and Fermi surfaces show full agreement with the electronic structure dete…

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Incidence and Clinical Impact of Right Ventricular Involvement (Biventricular Ballooning) in Takotsubo Syndrome

Background The short- and long-term prognosis of Takotsubo syndrome (TTS) presenting with right ventricular (RV) involvement remains poorly understood. Research Question What is the incidence and clinical outcome of RV involvement in TTS? Study Design and Methods This study analyzed 839 consecutive patients with TTS (758 female subjects and 81 male subjects) in a multicenter registry. RV involvement was defined as wall motion abnormality of the RV free wall, with or without apical involvement. The median long-term follow-up was 2.1 years (interquartile range, 0.3-4.5 years). The primary outcome was in-hospital and out-of-hospital all-cause mortality. The secondary end point was a composite …

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Observation of the rare B(s)(0) + decay from the combined analysis of CMS and LHCb data.

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported licence.-- et al.

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A topological current divider

We study the transport properties of a hybrid junction made of a ferromagnetic lead in electrical connection with the helical edge modes of a two-dimensional topological insulator. In this system, the time reversal symmetry, which characterizes the ballistic edge modes of the topological insulator, is explicitly broken inside the ferromagnetic region. This conflict situation generates unusual transport phenomena at the interface which are the manifestation of the interplay between the spin polarization of the injected current and the spin-momentum locking mechanism operating inside the topological insulator. We show that the spin polarized current originated in the ferromagnetic region is a…

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Impact of intra-aortic balloon counterpulsation on all-cause mortality among patients with Takotsubo syndrome complicated by cardiogenic shock: results from the German-Italian-Spanish (GEIST) registry

Abstract Aims Takotsubo syndrome (TTS) is an acute and reversible left ventricular dysfunction and can be complicated by cardiogenic shock (CS). However, few data are available on optimal care in TTS complicated by CS. Aim of this study was to evaluate short- and long-term impact of intra-aortic balloon pumping (IABP) on mortality in this setting. Methods and results In a multi-centre, international registry on TTS, 2248 consecutive patients were enrolled from 38 centres from Germany, Italy, and Spain. Of the 2248 patients, 212 (9.4%) experienced CS. Patients with CS had a higher prevalence of diabetes (27% vs. 19%), male sex (25% vs. 10%), and right ventricular involvement (10% vs. 5%) (P …

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Documento di consenso intersocietario ANMCO/ISS/AMD/ANCE/ARCA/FADOI/ GICR-IACPR/SICI-GISE/SIBioC/SIC/SICOA/ SID/SIF/SIMEU/SIMG/SIMI/SISA Colesterolo e rischio cardiovascolare: percorso diagnostico-terapeutico in Italia

Atherosclerotic cardiovascular disease still represents the leading cause of death in western countries. A wealth of scientific evidence demonstrates that increased blood cholesterol levels have a major impact on the outbreak and progression of atherosclerotic plaques. Moreover, several cholesterol-lowering pharmacological agents, including statins and ezetimibe, have proven effective in improving clinical outcomes. This document is focused on the clinical management of hypercholesterolemia and has been conceived by 16 Italian medical associations with the support of the Italian National Institute of Health. The authors have considered with particular attention the role of hypercholesterole…

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Assessment of the German and Italian Stress Cardiomyopathy Score for Risk Stratification for In-hospital Complications in Patients With Takotsubo Syndrome.

IMPORTANCE Takotsubo syndrome (TTS) is an acute, reversible heart failure syndrome featured by significant rates of in-hospital complications. There is a lack of data for risk stratification during hospitalization. OBJECTIVE To derive a simple clinical score for risk prediction of in-hospital complications among patients with TTS. DESIGN, SETTING, AND PARTICIPANTS In this prognostic study, 1007 consecutive patients were enrolled in the German and Italian Stress Cardiomyopathy (GEIST) registry from July 1, 2007, through December 31, 2017, and identified as the derivation cohort; 946 patients were enrolled in the Spanish Registry for Takotsubo Cardiomyopathy (RETAKO) as the external score val…

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The Deadly Quartet (Covid-19, Old Age, Lung Disease, and Heart Failure) Explains Why Coronavirus-Related Mortality in Northern Italy Was So High

Since its outbreak in China at the end of 2019, the new coronavirus disease (COVID-19) was characterized by both easy spreading and high mortality. The latter proved to be way more elevated in the North of Italy -with a peak of 18.4% in region Lombardia and even 31% in the city of Bergamo and surrounding county- than in the rest of the world. In an attempt to conceptualize the reasons for such a dramatic situation, four key elements have been identified: COVID-19 itself, old age, lung disease, and heart failure. Their harmful combination has been named “The deadly quartet”. The underlying risk factors, among which a lot of them are distinctive features of the population in northern Italy, …

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Focus on clinical practice: angiotensin-converting enzyme 2 and corona virus disease 2019: pathophysiology and clinical implications.

: ACE2 receptor has a broad expression pattern in the cellular membrane and provides a protective action against the development of cardiovascular diseases. Recently, this enzyme has become of extreme interest during the pandemic infection of COVID-19 (coronavirus disease 2019). This virus invades alveolar epithelium and cardiomyocytes using ACE2 as a transmembrane receptor. ACE2 is a counter-regulatory peptide that degrades Ang II into Ang 1-7, thereby attenuating the biological effects of the AT1 receptor. The binding between the spike protein of COVID-19 and the enzyme is crucial for the virus to enter the target cells, but whether an increase in ACE2 activity could facilitate the infect…

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Ballistic transport through quantum point contacts of multi-orbital oxides

Linear and non-linear transport properties through an atomic-size point contact based on oxides two-dimensional electron gas is examined using the tight-binding method and the $\mathbf{k\cdot p}$ approach. The ballistic transport is analyzed in contacts realized at the (001) interface between band insulators $LaAlO_3$ and $SrTiO_3$ by using the Landauer-B\"uttiker method for many sub-bands derived from three Ti 3d orbitals ($d_{yz}$, $d_{zx}$ and $d_{xy}$) in the presence of an out-of-plane magnetic field. We focus especially on the role played by the atomic spin-orbit coupling and the inversion symmetry breaking term pointing out three transport regimes: the first, at low energies, involvi…

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