(Poor) Roger Maris, 1964 Topps

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CARATTERIZZAZIONE DELL\u2019ATTRITO SU COMPONENTI PER APPLICAZIONI ORTODONTICHE MEDIANTE UN SIMULATORE \u201cIN VITRO\u201d

La diffusione delle tecniche a basso attrito (low friction) nell\u2019ambito di terapie ortodontiche per lo spostamento di un dente mediante applicazione di una forza debole (0.5 \u2013 0.7 N) o media (0.7-2.0 N) ha spinto la ricerca del settore odontoiatrico verso lo studio delle forze di attrito nel moto tra archetto ortodontico (archwire) e attacchi ortodontici (brackets). L\u2019esame della letteratura ha mostrato alcuni approcci molto semplificati alla misura dell\u2019attrito, con configurazioni piane, mediante simulazioni poco aderenti a quanto accade nel corso di una reale terapia ortodontica. Il presente lavoro si prefigge uno studio preliminare del fenomeno mediante caratterizzazione della forza di attrito citata, in condizioni sperimentali pi\uf9 simili a quelle reali,nelle quali la giacitura dei singoli brackets non \ue8 sul piano, come considerato in letteratura, ma nello spazio, replicando la geometria di una arcata dentaria completa. Le caratteristiche dimensionali e geometriche delle superfici striscianti tra le quali si genera attrito, sono tali da non consentire l\u2019implementazione di trasduttori per la misura diretta della forza di attrito ricercata. La soluzione messa a punto, che consente l\u2019utilizzo di un archwire e di brackets del tutto identici a quelli effettivamente impiegati nel trattamento del paziente, per la necessaria presenza dei cavi di collegamento per i segnali si presta esclusivamente ad uno studio \u2018in vitro\u2019, ma consente di ricavare informazioni localizzate lungo lo sviluppo curvilineo dell\u2019archwire e quindi dell\u2019arcata dentaria ad oggi non disponibili in letteratura. Oggetto del lavoro \ue8 quindi la progettazione e messa a punto di un dispositivo di prova opportunamente strumentato, che riproduce una arcata dentaria mascellare, riconfigurabile per riprodurre \u2018in vitro\u2019 le patologie ortodontiche del canino, che sono tra le pi\uf9 frequenti in ortodonzia. Il dispositivo possiede opportuni gradi di libert\ue0 per consentire l\u2019effettuazione di test che riproducano la patologia del canino in esame. La messa a punto del dispositivo ha riguardato la definizione della procedura di prova e la corretta selezione dei valori dei parametri operativi maggiormente influenti sulla qualit\ue0 dei risultati. I risultati ottenuti dal confronto quantitativo delle misure di valori di deformazione nell\u2019intorno dei brackets interessati dalla terapia ortodontica del canino, hanno mostrato chiaramente la diversa efficacia di differenti tipologie di legature in termini di attrito allo scorrimento dell\u2019archwire da cui consegue un diversa capacit\ue0 di esplicare la forza di richiamo lungo la direzione verticale che \ue8 il parametro qualificante della terapia ortodontica applicata alla correzione di dette patologie. Tutto ci\uf2, confermando la validit\ue0 dell\u2019approccio sperimentale basato sull\u2019impiego del simulatore in vitro proposto che supera le significative limitazioni dei simulatori in configurazione rettilinea descritti in letteratura, permette il conseguimento di risultati quantitativi utili al confronto delle prestazioni di diversi componenti ortodontici, permettendo cos\uec di ottimizzare il trattamento stesso

HeteroGenius: A Framework for Hybrid Analysis of Heterogeneous Software Specifications

Nowadays, software artifacts are ubiquitous in our lives being an essential part of home appliances, cars, cell phones, and even in more critical activities like aeronautics and health sciences. In this context software failures may produce enormous losses, either economical or, in the worst case, in human lives. Software analysis is an area in software engineering concerned with the application of diverse techniques in order to prove the absence of errors in software pieces. In many cases different analysis techniques are applied by following specific methodological combinations that ensure better results. These interactions between tools are usually carried out at the user level and it is not supported by the tools. In this work we present HeteroGenius, a framework conceived to develop tools that allow users to perform hybrid analysis of heterogeneous software specifications. HeteroGenius was designed prioritising the possibility of adding new specification languages and analysis tools and enabling a synergic relation of the techniques under a graphical interface satisfying several well-known usability enhancement criteria. As a case-study we implemented the functionality of Dynamite on top of HeteroGenius.Comment: In Proceedings LAFM 2013, arXiv:1401.056

Provably Correct Floating-Point Implementation of a Point-In-Polygon Algorithm

The problem of determining whether or not a point lies inside a given polygon occurs in many applications. In air traffic management concepts, a correct solution to the point-in-polygon problem is critical to geofencing systems for Unmanned Aerial Vehicles and in weather avoidance applications. Many mathematical methods can be used to solve the point-in-polygon problem. Unfortunately, a straightforward floating- point implementation of these methods can lead to incorrect results due to round-off errors. In particular, these errors may cause the control flow of the program to diverge with respect to the ideal real-number algorithm. This divergence potentially results in an incorrect point-in- polygon determination even when the point is far from the edges of the polygon. This paper presents a provably correct implementation of a point-in-polygon method that is based on the computation of the winding number. This implementation is mechanically generated from a source- to-source transformation of the ideal real-number specification of the algorithm. The correctness of this implementation is formally verified within the Frama-C analyzer, where the proof obligations are discharged using the Prototype Verification System (PVS)

A Mixed Real and Floating-Point Solver

Reasoning about mixed real and floating-point constraints is essential for developing accurate analysis tools for floating-point pro- grams. This paper presents FPRoCK, a prototype tool for solving mixed real and floating-point formulas. FPRoCK transforms a mixed formula into an equisatisfiable one over the reals. This formula is then solved using an off-the-shelf SMT solver. FPRoCK is also integrated with the PRECiSA static analyzer, which computes a sound estimation of the round-off error of a floating-point program. It is used to detect infeasible computational paths, thereby improving the accuracy of PRECiSA

Muon and Tau Neutrinos Spectra from Solar Flares

Solar neutrino flares and mixing are considered. Most power-full solar flare as the ones occurred on 23th February 1956, September 29th 1989, 28th October and on 2nd-4th November 2003 are sources of cosmic rays, X, gamma and neutrino bursts. These flares took place both on front or in the edge and in the hidden solar disk. The observed and estimated total flare energy should be a source of a prompt secondary neutrino burst originated, by proton-proton-pion production on the sun itself; a more delayed and spread neutrino flux signal arise by the solar charged flare particles reaching the terrestrial atmosphere. Our first estimates of neutrino signals in largest underground detectors hint for few events in correlation with, gamma,radio onser. Our approximated spectra for muons and taus from these rare solar eruption are shown over the most common background. The muon and tau signature is very peculiar and characteristic over electron and anti-electron neutrino fluxes. The rise of muon neutrinos will be detectable above the minimal muon threshold of 113 MeV. The rarest tau appearence will be possible only for hardest solar neutrino energies above 3.471 GeVComment: 14 pages, 4 figures, Vulcano Conference 200

Screening of at-risk blood donors for Chagas disease in non-endemic countries: Lessons from a 2-year experience in Tuscany, Italy

Background: Chagas disease (CD) is caused by the protozoan parasite Trypanosoma cruzi and is transmitted by blood-sucking triatomine insects in endemic areas of Latin America. Transmission can also occur via blood transfusion and is a major cause of CD in non-endemic areas. Objectives: The aim of the study was to assess the prevalence of anti-T. cruzi antibodies in blood donors at risk of infection in Tuscany, Italy, following the introduction of blood safety Italian legislation. Material and methods: Donors (N = 1985) were tested in 2016 to 2018 for anti-T. cruzi IgG using an immunochromatographic test (ICT). Chemiluminescent immunoassay (CLIA) was performed on ICT-positive donors to exclude CD, whereas enzyme-linked immunosorbent assay and Western blot were performed in case of discordant results. All assays were performed on CD patients (N = 10) for validation. Results: Ten blood donors had a positive ICT result, with a resulting T. cruzi seroprevalence of 0.5% but demonstrates negative results to CLIA, as well as to the other serological assays. The comparison of serological assays suggested a lower relative sensitivity of ICT. Conclusion: The results of this study confirm the significance of serological testing in the screening strategy for TT CD. However, they provide evidence for discontinuing the use of ICT as a screening test and suggest that a sensitive, specific and multi-sample format assay should be used at the national level for uniformity of results

The influence of chromium nitrides precipitation on the fatigue behavior of duplex stainless steels

This paper studies the fatigue behavior at room temperature of UNS S32205 and UNS S32750 duplex stainless steels (DSSs) under two thermal treatments. In both types of DSSs, thermal treatments at high temperature followed by water quenching (TTW) produces the precipitation of Cr2N within the ferrite phase. The amount of Cr2N increases mainly with the ferritic grain size independently of the nitrogen content. This nitride precipitation hardens the ferritic phase and produces a detrimental effect on the fatigue life of both steels.Fil: Hereñu, Silvina Andrea Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Física de Rosario (i); ArgentinaFil: Armas, A. F.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Física de Rosario (i); ArgentinaFil: Alvarez, Iris. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Física de Rosario (i); ArgentinaFil: Moscato, M. G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Física de Rosario (i); Argentin