WEB semantico: lo stato dell'arte

Il termine “Web Semantico” indica la trasformazione del World Wide Web in un ambiente dove i documenti pubblicati sono associati a specifiche informazioni, i metadati, che ne specifichino il contesto semantico. Queste informazioni, aggiunte ai documenti, devono avere una forma tale da permettere l’interrogazione, l’interpretazione ed, in generale, l’elaborazione automatica, da parte dei computer, del contenuto dei documenti stessi. L’obiettivo principale del WS è fare in modo che le macchine riescano, autonomamente, ad estrarre e a dedurre nuova conoscenza. Scopo della tesi è quello di fare il “punto della situazione attuale” del Web Semantico. Il lavoro è strutturato in 4 parti: presentazione del Web attuale nei suoi vari aspetti, evidenziazione dei suoi limiti principali, esposizione delle tecnologie dell’architettura a livelli del WS e presentazione di un’applicazione, già operativa, che utilizza le tecniche finora sviluppate.ope

Formation and Properties of Astrophysical Carbonaceous Dust. I. Ab-initio Calculations of the Configuration and Binding Energies of Small Carbon Clusters

The binding energies of n < 100 carbon clusters are calculated using the ab initio density functional theory code Quantum Espresso. Carbon cluster geometries are determined using several levels of classical techniques and further refined using density functional theory. The resulting energies are used to compute the work of cluster formation and the nucleation rate in a saturated, hydrogen-poor carbon gas. Compared to classical calculations that adopt the capillary approximation, we find that nucleation of carbon clusters is enhanced at low temperatures and depressed at high temperatures. This difference is ascribed to the different behavior of the critical cluster size. We find that the critical cluster size is at n = 27 or n = 8 for a broad range of temperatures and saturations, instead of being a smooth function of such parameters. The results of our calculations can be used to follow carbonaceous cluster/grain formation, stability, and growth in hydrogen-poor environments, such as the inner layers of core-collapse supernovae and supernova remnants.This is the publisher’s final pdf. The article is copyrighted by the American Astronomical Society and published by the Institute of Physics Publishing. It can be found at: http://iopscience.iop.org/0004-637X

Advanced modeling of materials with PAOFLOW 2.0:New features and software design

Recent research in materials science opens exciting perspectives to design novel quantum materials and devices, but it calls for quantitative predictions of properties which are not accessible in standard first principles packages. PAOFLOW, is a software tool that constructs tight-binding Hamiltonians from self consistent electronic wavefunctions by projecting onto a set of atomic orbitals. The electronic structure provides numerous materials properties that otherwise would have to be calculated via phenomenological models. In this paper, we describe recent re-design of the code as well as the new features and improvements in performance. In particular, we have implemented symmetry operations for unfolding equivalent k-points, which drastically reduces the runtime requirements of first principles calculations, and we have provided internal routines of projections onto atomic orbitals enabling generation of real space atomic orbitals. Moreover, we have included models for non-constant relaxation time in electronic transport calculations, doubling the real space dimensions of the Hamiltonian as well as the construction of Hamiltonians directly from analytical models. Importantly, PAOFLOW has been now converted into a Python package, and is streamlined for use directly within other Python codes. The new object oriented design treats PAOFLOW's computational routines as class methods, providing an API for explicit control of each calculation.</p

WEB semantico: lo stato dell'arte

Il termine “Web Semantico” indica la trasformazione del World Wide Web in un ambiente dove i documenti pubblicati sono associati a specifiche informazioni, i metadati, che ne specifichino il contesto semantico. Queste informazioni, aggiunte ai documenti, devono avere una forma tale da permettere l’interrogazione, l’interpretazione ed, in generale, l’elaborazione automatica, da parte dei computer, del contenuto dei documenti stessi. L’obiettivo principale del WS è fare in modo che le macchine riescano, autonomamente, ad estrarre e a dedurre nuova conoscenza. Scopo della tesi è quello di fare il “punto della situazione attuale” del Web Semantico. Il lavoro è strutturato in 4 parti: presentazione del Web attuale nei suoi vari aspetti, evidenziazione dei suoi limiti principali, esposizione delle tecnologie dell’architettura a livelli del WS e presentazione di un’applicazione, già operativa, che utilizza le tecniche finora sviluppate

COVID-19 Vaccination in Italian Children: The Limits of Parental Rights

SARS-CoV-2 vaccination campaigns initially targeted the adult population. After the authorization of the main agencies, including the EMA (European Medicines Agency), the European Vaccination Plan now involves young people between the ages of 12–17 and 5–11. In assessing the child’s “best interests”, the refusal of vaccination by parents or guardians, in addition to the increased circulation of the virus, is responsible for the risk of social distancing. This reduction in social contacts, particularly during very sensitive ages such as adolescence, has been linked to the increased incidence of psychiatric illness, a significant reason for extending vaccination against SARS-CoV-2 in these younger children. One may consider that government should issue a law that allows the child to decide on the vaccination plan, even without the consent of the parents or guardians, without the need for a judge’s ruling. The availability of the child should be the point of reference, according to the National Bioethics Committee, for consent to vaccination. The authors investigate the subject in depth in order to counteract vaccination hesitation, and promote the dissemination of correct scientific information, using every different possible communication tool, as well as social networks and schools

Independent Quality Assessment of Essential Climate Variables: Lessons Learned from the Copernicus Climate Change Service

If climate services are to lead to effective use of climate information in decision-making to enable the transition to a climate-smart, climate-ready world, then the question of trust in the products and services is of paramount importance. The Copernicus Climate Change Service (C3S) has been actively grappling with how to build such trust: provision of demonstrably independent assessments of the quality of products, which was deemed an important element in such trust-building processes. C3S provides access to essential climate variables (ECVs) from multiple sources to a broad set of users ranging from scientists to private companies and decision-makers. Here we outline the approach ­undertaken to coherently assess the quality of a suite of observation- and reanalysis-based ECV products covering the atmosphere, ocean, land, and cryosphere. The assessment is based on four pillars: basic data checks, maturity of the datasets, fitness for purpose (scientific use cases and climate studies), and guidance to users. It is undertaken independently by scientific experts and presented alongside the datasets in a fully traceable, replicable, and transparent manner. The methodology deployed is detailed, and example assessments are given. These independent scientific quality assessments are intended to guide users to ensure they use tools and datasets that are fit for purpose to answer their specific needs rather than simply use the first product they alight on. This is the first such effort to develop and apply an assessment framework consistently to all ECVs. Lessons learned and future perspectives are outlined to potentially improve future assessment activities and thus climate services.This work is funded by European Copernicus Climate Change Service (C3S) implemented by European Centre for Medium-Range Weather Forecasts (ECMWF) under the service contract Independent Assessment on ECVs led by the National Research Council of Italy (CNR) with the service contract number as ECMWF/Copernicus/2017/C3S_511_CNR.Peer reviewe