748 research outputs found

    Discovering Tau and Muon Solar Neutrino Flares above backgrounds

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    Solar neutrino flares astronomy is at the edge of its discover. High energy flare particles (protons, alpha) whose self scattering within the solar corona is source of a rich prompt charged pions are also source of sharp solar neutrino "burst" (at tens-hundred MeV) produced by their pion-muon primary decay in flight. This brief (minute) solar neutrino "burst" at largest peak overcome by four-five order of magnitude the steady atmospheric neutrino noise at the Earth. Later on, solar flare particles hitting the terrestrial atmosphere may marginally increase the atmospheric neutrino flux without relevant consequences. Largest prompt "burst" solar neutrino flare may be detected in present or better in future largest neutrino underground neutrino detectors. Our estimate for the recent and exceptional October - November 2003 solar flares gives a number of events above or just near unity for Super-Kamiokande. The neutrino spectra may reflect in a subtle way the neutrino flavour mixing in flight. A surprising tau appearance may even occur for a hard ({E}_{nu}_{mu}--> {E}_{nu}_{tau} > 4 GeV) flare spectra. A comparison of the solar neutrino flare (at their birth place on Sun and after oscillation on the arrival on the Earth) with other neutrino foreground is here described and it offer an independent road map to disentangle the neutrino flavour puzzles and its secret flavour mixing angles .Comment: 10 pages, 7 figures, Noon 2004 Conference, Februry 200

    HeteroGenius: A Framework for Hybrid Analysis of Heterogeneous Software Specifications

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    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

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

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    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

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    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

    La Ricerca-Azione Partecipativa come pedagogia della con-vers-azione. Un percorso di co-progettazione per la costruzione di una comunitĂ  educante

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    This paper shows the early results of a Participatory Action-Research (PAR) in which University, School, and Third Sector of the city of Palermo dialogue with each other to design new educational systems’ architectures. Within the theoretical framework provided by Universal Design for Learning, Outdoor Education and the Capability Approach, the chosen methodology is the informal conversation of the World Cafè. The working tables reflected on the implications of the intertwining among educational agencies, technological innovations, and territorial fabric. From these significant exchanges emerged perspectives of emancipation and co-construction of inclusive contexts for learning and social innovation

    On Meme Self-Adaptation in Spatially-Structured Multimemetic Algorithms

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    NMA 2014Multimemetic algorithms (MMAs) are memetic algorithms that explicitly exploit the evolution of memes, i.e., non-genetic expressions of problem-solving strategies. We consider a class of MMAs in which these memes are rewriting rules whose length can be fixed during the run of the algorithm or self-adapt during the search process. We analyze this self-adaptation in the context of spatially-structured MMAs, namely MMAs in which the population is endowed with a certain topology to which interactions (from the point of view of selection and variation operators) are constrained. For the problems considered, it is shown that panmictic (i.e., non-structured) MMAs are more sensitive to this self-adaptation, and that using variable-length memes seems to be a robust strategy throughout different population structures.This work is partially supported by MICINN project ANYSELF (TIN2011-28627-C04-01), by Junta de Andaluía project DNEMESIS (P10-TIC-6083) and by Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech

    QAPgrid: A Two Level QAP-Based Approach for Large-Scale Data Analysis and Visualization

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    Background: The visualization of large volumes of data is a computationally challenging task that often promises rewarding new insights. There is great potential in the application of new algorithms and models from combinatorial optimisation. Datasets often contain “hidden regularities” and a combined identification and visualization method should reveal these structures and present them in a way that helps analysis. While several methodologies exist, including those that use non-linear optimization algorithms, severe limitations exist even when working with only a few hundred objects. Methodology/Principal Findings: We present a new data visualization approach (QAPgrid) that reveals patterns of similarities and differences in large datasets of objects for which a similarity measure can be computed. Objects are assigned to positions on an underlying square grid in a two-dimensional space. We use the Quadratic Assignment Problem (QAP) as a mathematical model to provide an objective function for assignment of objects to positions on the grid. We employ a Memetic Algorithm (a powerful metaheuristic) to tackle the large instances of this NP-hard combinatorial optimization problem, and we show its performance on the visualization of real data sets. Conclusions/Significance: Overall, the results show that QAPgrid algorithm is able to produce a layout that represents the relationships between objects in the data set. Furthermore, it also represents the relationships between clusters that are feed into the algorithm. We apply the QAPgrid on the 84 Indo-European languages instance, producing a near-optimal layout. Next, we produce a layout of 470 world universities with an observed high degree of correlation with the score used by the Academic Ranking of World Universities compiled in the The Shanghai Jiao Tong University Academic Ranking of World Universities without the need of an ad hoc weighting of attributes. Finally, our Gene Ontology-based study on Saccharomyces cerevisiae fully demonstrates the scalability and precision of our method as a novel alternative tool for functional genomics
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