20 research outputs found
Contact Lorentzian manifolds
No full textAbstractContact structures with associated pseudo-Riemannian metrics were studied by D. Perrone and the present author (2010) in [8]. We focus here on contact Lorentzian structures, emphasizing their relationship and analogies with respect to the Riemannian case
HERAKLEIA di Lucania (Basilicata, Italia). Forme e funzioni delle ceramiche d’uso quotidiano in una città italiota tra III e II secolo a.C.
No full textHERAKLEIA di Lucania (Basilicata, Italia). Forme e funzioni delle ceramiche d’uso quotidiano in una città italiota tra III e II secolo a.C.
No full textCet article propose une présentation des céramiques produites dans la seconde moitié du IIIe s. av. J.-C. dans un atelier de la ville italiote d’Herakleia. Il sʼagit exclusivement de céramiques destinées à un usage quotidien, en relation avec les différents stades de la conservation, de la préparation, de la cuisson et de la consommation de nourriture. Les céramiques ont été classées tout d’abord selon leur fonction originelle, et ensuite avec une numérotation ouverte. Les productions des ateliers d’Herakleia offrent un précieux outil d’analyse pour les problèmes liés au IIIe s. av. J.-C. et même plus spécifiquement pour la seconde moitié de ce siècle, car elles fournissent un contexte « fermé » chronologiquement. En ce qui concerne Herakleia, elles contribuent à témoigner de la vitalité économique de la ville à un moment généralement considéré comme une période de crise pour toutes les villes italiotes de la côte Ionienne (Metaponte, Tarente).Il contributo presenta un quadro delle ceramiche prodotte nella seconda metà del III sec. a.C. in unʼarea artigianale della città italiota di Herakleia. Si tratta esclusivamente di vasellame di uso quotidiano, collegato con i diversi momenti della conservazione, della preparazione, della cottura e del consumo del cibo. Le ceramiche sono state articolate in base alla loro funzione originaria e secondo un criterio univoco di classificazione aperta. Le produzioni delle officine eracleote, poiché costituiscono un contesto “chiuso” cronologicamente, offrono un prezioso strumento diagnostico per le problematiche relative al III sec. a.C. e ancor più specificatamente alla seconda metà. Per quanto riguarda Herakleia, esse contribuiscono ad attestare la vitalità economica dellʼabitato in un periodo solitamente ritenuto di crisi per tutte le città italiote dellʼarco ionico (Metaponto, Taranto)
Le scuole rurali in Sicilia fra prossimità e spaesamento: dalla terra alla terra
No full textIn this article the author presents a research project that highlights the role of rural schools in Sicily (from 1919-23 to 2008). These schools were built for both greater ubiquity for a broader education and promotion of culture of citizenship.A lot of rural schools have been closed for economic and social reasons, but they have for years pursued the pivotal and delicate role of bringing knowledge among the children of the farmers, limiting the scholastic dispersion and favouring the processes of social inclusion. Rural schools are civic garrisons to revalue in a prospective of permanent learning through different uses.This study started between the end of 2008 and February 2009. The first results of surveys in the territory have been exposed during the congress in Rome March 16, 2009, at a conference held at the University “Roma Tre”. From November 2009 till today the research has continued at both regional and national levels(Rural area around Rome, Tuscany and Umbria).Il presente articolo introduce un progetto di ricerca che evidenzia il ruolo delle scuole rurali in Sicilia, dal 1919-23 al 2008, sia per una maggiore capillarità dell’istruzione sia per una più ampia promozione della cultura della cittadinanza. Molte scuole rurali sono state chiuse per motivi economici e sociali ma hanno per anni assolto un prezioso compito educativo portando la conoscenza anche fra i figli dei contadini, limitando la dispersione scolasticae favorendo i processi di inclusione sociale. Le scuole rurali e montane sono presidi civici da rivalutare anche in una prospettiva di apprendimento permanente tramite un loro diverso utilizzo.Lo studio ha preso l’avvio fra la fine del 2008 ed il febbraio 2009. Le prime rilevazioni sul territorio sono state esposte in sede congressuale in Roma il 16 Marzo 2009, in occasione di un convegno svoltosi presso l’Università “Roma Tre”. Dal Novembre 2009 alla data odierna la ricerca è continuata sia inambito regionale che nazionale (Agro romano, Toscana e Umbria)
Algebraic Properties of Curvature Operators in Lorentzian Manifolds with Large Isometry Groups
No full textTogether with spaces of constant sectional curvature and products of a real line
with a manifold of constant curvature, the socalled Egorov spaces and ε-spaces exhaust the class of n-dimensional Lorentzian manifolds admitting a group of isometries of dimension at least 0.5n(n − 1) + 1, for almost all values of n [Patrangenaru V., Geom. Dedicata 102 (2003), 25–33]. We shall prove that the curvature tensor of these spaces satisfi several interesting algebraic properties. In particular, we will show that Egorov spaces are Ivanov–Petrova manifolds, curvature-Ricci commuting (indeed, semi-symmetric) and P-spaces, and that ε-spaces are Ivanov–Petrova and curvature-curvature commuting manifolds.First author supported by funds of MIUR (PRIN 2007) and the University of Salento. Second
author supported by projects MTM2009-07756 and INCITE09 207 151 PR (Spain). Finally the
authors would like to express their thanks to the Referees of this paper for pointing out some
mistakes in the original manuscript
Neuropathic pain and ultrasonography: A multiperspective literature evaluation
No full textAmong the tools useful for the management of neuropathic pain, ultrasound presents several advantages, shown by the literature. We assessed the scientific production about neuropathic pain and ultrasound from different points of view: general topics, journal categories, geographical origin and lexical analysis. We searched papers on PubMed using the Medical Subject Headings “neuropathic pain” AND “ultrasound”. We collected data about the journals where the papers were published, the country of the affiliation of the first author. For the lexical analysis, we evaluated the presence of selected words in the papers, and we built a graph representing the connections among words and papers. The papers were focused on the use of ultrasound as a diagnostic tool and guide for the therapy, assessing its application in different diseases such as Morton’s neuroma and piriformis syndrome. The most represented journal category was anesthesia while the most common country the United States of America. The lexical analysis confirmed the importance of ultrasound for diagnosis of specific disease and treatment of pain. The described approaches provide a multiperspective evaluation of the literature and may support the interpretation of the information contained by the papers
