1,147 research outputs found

    Exploring the association of Fermi sources with Young Stellar Objects

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    Massive protostars have associated bipolar outflows which can produce strong shocks when interact with the surrounding medium. Some theoretical models predict that particle acceleration at relativistic velocities can occur leading to gamma ray emission. In order to identify young stellar objects (YSO) that might emit gamma rays, we have crossed the Fermi First Year Catalog with catalogs of known YSOs, obtaining a set of candidates by spatial correlation. We have conducted Montecarlo simulations to find the probability of chance coincidence. Our results indicate that ∼70% of the candidates should be gamma-ray sources with a confidence of ∼5ρ. σ International Astronomical Union 2011.Instituto Argentino de Radioastronomí

    Exploring the association of Fermi sources with Young Stellar Objects

    Get PDF
    Massive protostars have associated bipolar outflows which can produce strong shocks when interact with the surrounding medium. Some theoretical models predict that particle acceleration at relativistic velocities can occur leading to gamma ray emission. In order to identify young stellar objects (YSO) that might emit gamma rays, we have crossed the Fermi First Year Catalog with catalogs of known YSOs, obtaining a set of candidates by spatial correlation. We have conducted Montecarlo simulations to find the probability of chance coincidence. Our results indicate that ∼70% of the candidates should be gamma-ray sources with a confidence of ∼5ρ. σ International Astronomical Union 2011.Instituto Argentino de Radioastronomí

    Familial amyloid polyneuropathy associated with TTRSer50Arg mutation in two Iberian families presenting a novel single base change in the mutant gene

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    Amyloid. 2007 Jun;14(2):147-52. Familial amyloid polyneuropathy associated with TTRSer50Arg mutation in two Iberian families presenting a novel single base change in the mutant gene. Munar-Qués M, Masjuan J, Coelho T, Moreira P, Viader-Farré C, Saraiva MJ. Grupo de Estudio de la PAF, Plaza Olivar 5, 07002 Palma de Mallorca, Majorca, Spain. [email protected] Abstract We present two families, from Spain and Portugal, with familial amyloid polyneuropathy (FAP) associated with the mutation TTRSer50Arg. This mutation was first described in two Japanese patients from independent families and later in a French-Italian patient and a Vietnamese family. The two families presented here, are the first to be diagnosed with this mutation in the Iberian Peninsula. In the patients of both families, FAP was very aggressive as they rapidly developed multiple symptoms with progressive deterioration; we emphasize the presence of severe orthostatic hypotension in the Spanish proband which confined him to a wheelchair. This proband was the first patient with this mutation to have undergone liver transplantation and results were encouraging. The mutation was detected in four patients and one disease-free relative by DNA sequencing of exon 3 and induced mutation restriction analysis. The most outstanding feature was the single base transversion A to C in codon 50 (CGT instead of AGT), whereas in both Japanese patients and the French-Italian patient it was T to G (AGG instead of AGT). To our knowledge only six FAP mutations with more than one single nucleotide mutation for the same codon have been reported to date. PMID: 17577688 [PubMed - indexed for MEDLINE

    ASTRI SST-2M prototype and mini-array simulation chain, data reduction software, and archive in the framework of the Cherenkov Telescope Array

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    The Cherenkov Telescope Array (CTA) is a worldwide project aimed at building the next-generation ground-based gamma-ray observatory. Within the CTA project, the Italian National Institute for Astrophysics (INAF) is developing an end-to-end prototype of the CTA Small-Size Telescopes with a dual-mirror (SST-2M) Schwarzschild-Couder configuration. The prototype, named ASTRI SST-2M, is located at the INAF "M.C. Fracastoro" observing station in Serra La Nave (Mt. Etna, Sicily) and is currently in the scientific and performance validation phase. A mini-array of (at least) nine ASTRI telescopes has been then proposed to be deployed at the Southern CTA site, by means of a collaborative effort carried out by institutes from Italy, Brazil, and South-Africa. The CTA/ASTRI team is developing an end-to-end software package for the reduction of the raw data acquired with both ASTRI SST-2M prototype and mini-array, with the aim of actively contributing to the global ongoing activities for the official data handling system of the CTA observatory. The group is also undertaking a massive Monte Carlo simulation data production using the detector Monte Carlo software adopted by the CTA consortium. Simulated data are being used to validate the simulation chain and evaluate the ASTRI SST-2M prototype and mini-array performance. Both activities are also carried out in the framework of the European H2020-ASTERICS (Astronomy ESFRI and Research Infrastructure Cluster) project. A data archiving system, for both ASTRI SST-2M prototype and mini-array, has been also developed by the CTA/ASTRI team, as a testbed for the scientific archive of CTA. In this contribution, we present the main components of the ASTRI data handling systems and report the status of their development.Comment: Proceedings of the 35th International Cosmic Ray Conference (ICRC 2017), Bexco, Busan, Korea. All CTA contributions at arXiv:1709.0348

    Aesthetic appreciation: event-related field and time-frequency analyses

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    Improvements in neuroimaging methods have afforded significant advances in our knowledge of the cognitive and neural foundations of aesthetic appreciation. We used magnetoencephalography (MEG) to register brain activity while participants decided about the beauty of visual stimuli. The data were analyzed with event-related field (ERF) and Time-Frequency (TF) procedures. ERFs revealed no significant differences between brain activity related with stimuli rated as “beautiful” and “not beautiful.” TF analysis showed clear differences between both conditions 400 ms after stimulus onset. Oscillatory power was greater for stimuli rated as “beautiful” than those regarded as “not beautiful” in the four frequency bands (theta, alpha, beta, and gamma). These results are interpreted in the frame of synchronization studies

    Exploring the association of Fermi sources with Young Stellar Objects

    Get PDF
    Massive protostars have associated bipolar outflows which can produce strong shocks when interact with the surrounding medium. Some theoretical models predict that particle acceleration at relativistic velocities can occur leading to gamma ray emission. In order to identify young stellar objects (YSO) that might emit gamma rays, we have crossed the Fermi First Year Catalog with catalogs of known YSOs, obtaining a set of candidates by spatial correlation. We have conducted Montecarlo simulations to find the probability of chance coincidence. Our results indicate that ∼70% of the candidates should be gamma-ray sources with a confidence of ∼5ρ. σ International Astronomical Union 2011.Instituto Argentino de Radioastronomí

    Contribution of Plasmodium knowlesi to Multispecies Human Malaria Infections in North Sumatera, Indonesia.

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    Background: As Indonesia works toward the goal of malaria elimination, information is lacking on malaria epidemiology from some western provinces. As a basis for studies of antimalarial efficacy, we set out to survey parasite carriage in 3 communities in North Sumatera Province. Methods: A combination of active and passive detection of infection was carried out among communities in Batubara, Langkat, and South Nias regencies. Finger-prick blood samples from consenting individuals of all ages provided blood films for microscopic examination and blood spots on filter paper. Plasmodium species were identified using nested polymerase chain reaction (PCR) of ribosomal RNA genes and a novel assay that amplifies a conserved sequence specific for the sicavar gene family of Plasmodium knowlesi. Results: Of 3731 participants, 614 (16.5%) were positive for malaria parasites by microscopy. PCR detected parasite DNA in samples from 1169 individuals (31.3%). In total, 377 participants (11.8%) harbored P. knowlesi. Also present were Plasmodium vivax (14.3%), Plasmodium falciparum (10.5%) and Plasmodium malariae (3.4%). Conclusions: Amplification of sicavar is a specific and sensitive test for the presence of P. knowlesi DNA in humans. Subpatent and asymptomatic multispecies parasitemia is relatively common in North Sumatera, so PCR-based surveillance is required to support control and elimination activities
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