Geometry of Winter Model

By constructing the Riemann surface controlling the resonance structure of Winter model, we determine the limitations of perturbation theory. We then derive explicit non-perturbative results for various observables in the weak-coupling regime, in which the model has an infinite tower of long-lived resonant states. The problem of constructing proper initial wavefunctions coupled to single excitations of the model is also treated within perturbative and non-perturbative methods.Comment: latex file, 56 pages, 15 figure

Renormalization in Winter Model

We show that metastable states in Winter model can be related to the eigenstates of a particle in a box by means of renormalization and mixing.Comment: Version accepted by Phys. Rev. A, containing some small additional comments and explanation

SARS-CoV-2 was already circulating in Italy, in early December 2019

– OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) identified in China, in December 2019 determines COronaVIrus Disease 19 (COVID-19). Whether or not the virus was present in Italy earlier the first autochthonous COVID-19 case was diagnosed is still uncertain. We aimed to identify anti-SARS-CoV-2 antibodies in sera collected from 4th November 2019 to 9th March 2020, in order to assess the possible spread of the virus in Italy earlier than the first official national diagnosis. PATIENTS AND METHODS: Anti-SARS-CoV-2 antibodies were evaluated in retrospective serum samples from 234 patients with liver diseases (Hep-patients) and from 56 blood donors (BDs). We used two rapid serologic tests which were confirmed by a validated chemoluminescence assay. RESULTS: Via rapid tests, we found 10/234 (4.3%) IgG-positive and 1/234 (0.4%) IgM-positive cases in the Hep-patient group. Two/56 (3.6%) IgG-positive and 2/56 (3.6%) IgM-positive cases were detected in BD group. Chemoluminescence confirmed IgG-positivity in 3 Hep-patients and 1 BD and IgM-positivity in 1 Hep-patient. RNAemia was not detected in any of the subjects, rendering the risk of transfusion transmission negligible. CONCLUSIONS: Our results suggest an early circulation of SARS-CoV-2 in Italy, before the first COVID-19 cases were described in China. Rapid tests have multiple benefits; however, a confirmation assay is required to avoid false positive results

Early use of abiraterone and radium-223 in metastatic prostate cancer

[No abstract available

On the solvability of the discrete second Painlevé equation

The inverse monodromy method for studying the Riemann-Hilbert problem associated with classical Painlevé equations is applied to the discrete second Painlevé equation

Schlesinger transformations for discrete second Painlevé equation: D-PII

A method to obtain the Schlesinger transformations for the standard discrete second Painlevé equation, d-PII, is given. The procedure involves formulating a Riemann-Hilbert problem for a transformation matrix which transforms the solution of the linear problem but leaves the associated monodromy data the same. © 2005 Elsevier B.V. All rights reserved

Multiscale expansions of difference equations in the small lattice spacing regime, and a vicinity and integrability test. I

We propose an algorithmic procedure i) to study the ``distance'' between an integrable PDE and any discretization of it, in the small lattice spacing epsilon regime, and, at the same time, ii) to test the (asymptotic) integrability properties of such discretization. This method should provide, in particular, useful and concrete informations on how good is any numerical scheme used to integrate a given integrable PDE. The procedure, illustrated on a fairly general 10-parameter family of discretizations of the nonlinear Schroedinger equation, consists of the following three steps: i) the construction of the continuous multiscale expansion of a generic solution of the discrete system at all orders in epsilon, following the Degasperis - Manakov - Santini procedure; ii) the application, to such expansion, of the Degasperis - Procesi (DP) integrability test, to test the asymptotic integrability properties of the discrete system and its ``distance'' from its continuous limit; iii) the use of the main output of the DP test to construct infinitely many approximate symmetries and constants of motion of the discrete system, through novel and simple formulas.Comment: 34 pages, no figur

Context as a non-ontological determinant of semantics

The final publication is available at Springer via http://dx.doi.org/110.1007/978-3-540-92235-3_11Proceedings of Third International Conference on Semantic and Digital Media Technologies, SAMT 2008, Koblenz, Germany, December 3-5, 2008.This paper proposes an alternative to formal annotation for the representation of semantics. Drawing on the position of most of last century’s linguistics and interpretation theory, the article argues that meaning is not a property of a document, but an outcome of a contextualized and situated process of interpretation. The consequence of this position is that one should not quite try to represent the meaning of a document (the way formal annotation does), but the context of the activity of which search is part. We present some general considerations on the representation and use of the context, and a simple example of a technique to encode the context represented by the documents collected in the computer in which one is working, and to use them to direct search. We show preliminary results showing that even this rather simpleminded context representation can lead to considerable improvements with respect to commercial search engines