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The detection and analysis of oscillations in binary star systems is critical in understanding stellar structure and evolution. This is partly because such systems have the same initial chemical composition and age. Solar-like oscillations have been detected by Kepler in both components of the asteroseismic binary HD 176465. We present an independent modelling of each star in this binary system. Stellar models generated using MESA (Modules for Experiments in Stellar Astrophysics) were fitted to both the observed individual frequencies and complementary spectroscopic parameters. The individual theoretical oscillation frequencies for the corresponding stellar models were obtained using GYRE as the pulsation code. A Bayesian approach was applied to find the probability distribution functions of the stellar parameters using AIMS (Asteroseismic Inference on a Massive Scale) as the optimisation code. The ages of HD 176465 A and HD 176465 B were found to be 2.81 ± 0.48 Gyr and 2.52 ± 0.80 Gyr, respectively. These results are in agreement when compared to previous studies carried out using other asteroseismic modelling techniques and gyrochronology. [ABSTRACT FROM AUTHOR]

In this work, we present a new method to determine the surface gravity of δ Sct stars. We used a refined Δv-...relation and the stellar parallaxes or luminosities to determine their masses and radii. A comparison with the data obtained from the binary analysis, has shown that the values found by both methods are equivalent, within the uncertainties. Moreover, thanks to the refined relation, the uncertainties in log g are of the order of those usually estimated with high-resolution spectroscopy. Because of that, this new method to determine the surface gravity is an important step forward to break the degeneracy problem in the spectroscopic analysis. [ABSTRACT FROM AUTHOR]

The increased amount of high precision seismic data for solar-like stars calls for the existence of tools that can extract information from such data. In the case of the study of acoustic glitches there are no publicly available tools and most of the existing ones require a deep knowledge of their implementation. In this work a tool is presented that aims to both simplify the interaction with the user and also be capable of working automatically to determine properties of acoustic glitches from seismic data of solar-like stars. This tool is shown to work with both the Sun and other solar analogs but there are still some limitations to the methods being used when considering smaller frequency datasets. [ABSTRACT FROM AUTHOR]

We present a new spectroscopic calibration for a fast estimate of Teff and [Fe/H] for FGK dwarfs and GK giant stars. We used spectra from a joint sample of 708 stars, composed by 451 FGK dwarfs and 257 GK-giant stars with homogeneously determined spectroscopic stellar parameters. We have derived 322 EW line-ratios and 100 FeI lines that can be used to compute Teff and [Fe/H], respectively. We show that these calibrations are effective for FGK dwarfs and GK-giant stars in the following ranges: 4500 K < Teff < 6500 K, 2.5 < log g < 4.9 dex, and –0.8 < [Fe/H] < 0:5 dex. The new calibration has a standard deviation of 74 K for Teff and 0.07 dex for [Fe/H]. We use four independent samples of stars to test and verify the new calibration, a sample of giant stars, a sample composed of Gaia FGK benchmark stars, a sample of GK-giant stars from the DR1 of the Gaia-ESO survey, and a sample of FGK-dwarf stars. We present a new computer code, GeTCal, for automatically producing new calibration files based on any new sample of stars. [ABSTRACT FROM AUTHOR]

Nowadays is common to have health care institutions providing remote assistance, such as, remote diagnosis (telediagnosis) and second opinion from a specialized physicians (teleconsultation), to others medical institutions that do not have specialized human resources, or even for educational propose. The evolution of technology creates opportunities to improve telemedicine services. This article focuses on the improvement of services to support telemedicine in a paradigm "any-time and anywhere" adapting a new emerging computer concept, which is cloud computing. Throughout the paper is presented a software as a service that can be used by radiologist for store, share, visualize and analyse medical images, in compliant with DICOM (Digital Imaging and Communications in Medicine) format, from anywhere. Furthermore, the presented architecture allows to improve real time and asynchronous collaboration. To support collaborative activities and their coordination, we created a computer-supported collaborative work service based on Openfire real time collaboration (RTC) server, that use Extensible Messaging and Presence Protocol (XMPP) for instant messaging and presence. Finally, the platform was deployed on an Internet Cloud provider and some results was presented and discussed. [ABSTRACT FROM AUTHOR]

Nowadays is common to have health care institutions providing remote assistance, such as, remote diagnosis (telediagnosis) and second opinion from a specialized physicians (teleconsultation), to others medical institutions that do not have specialized human resources, or even for educational propose. The evolution of technology creates opportunities to improve telemedicine services. This article focuses on the improvement of services to support telemedicine in a paradigm “any-time and anywhere” adapting a new emerging computer concept, which is cloud computing. Throughout the paper is presented a software as a service that can be used by radiologist for store, share, visualize and analyse medical images, in compliant with DICOM (Digital Imaging and Communications in Medicine) format, from anywhere. Furthermore, the presented architecture allows to improve real time and asynchronous collaboration. To support collaborative activities and their coordination, we created a computer-supported collaborative work service based on Openfire real time collaboration (RTC) server, that use Extensible Messaging and Presence Protocol (XMPP) for instant messaging and presence. Finally, the platform was deployed on an Internet Cloud provider and some results was presented and discussed. [ABSTRACT FROM PUBLISHER]

Spectroscopy diagnostics in He and H plasma created by NOVA-UNICAMP Tokamak have been performed by the use of three visible and one VUV spectrometers covering four toroidal positions. Comparison between visible and VUV ion temperature measurements are presented. The Balmer and Lyman hydrogen line emissions during tokamak discharge seen to have same type of behavior. The time evolutions of carbon line emissions, with different degrees of ionization levels, showed to be opposite between high and low plasma ionization. The high density operation and 2 kHz oscillation present throughout discharge, restrained the increase of ion temperature caused by periodical touching of the plasma with limiter of the tokamak. [ABSTRACT FROM AUTHOR]

The soft x-ray transmission microscope XM-1 was used to examine the alkali-silica reaction, a deleterious reaction that produces expansion in some concrete structures. Reactions of silica gel in alkaline solutions (pH ≥ 12.4) in the presence of pore solution cations (Na[sup +, Ca[sup ++]) and a chemical additive (CaCl[sub 2]) were observed, and the morphology of the reaction products were examined to investigate the mechanisms of expansion and expansion control. From the investigation of the effect of pore solution cations, it was found that reactive silica combined with alkalis present in the pore solution to produce a reaction gel capable of swelling, while the reaction of silica in the presence of calcium ions alone resulted in the formation of a nonswelling product — calcium silicate hydrate. Reaction of the silica gel in the presence of CaCl[sub 2] also resulted in the formation of calcium silicate hydrate. [ABSTRACT FROM AUTHOR]

The helium ionization zone in a star leaves a characteristic signature on its oscillation frequencies, which can be used to estimate the helium content in the envelope of the star. We use the oscillation frequencies of 16 Cyg A and B, obtained using 2.5 years of Kepler data, to estimate the envelope helium abundance of these stars. We find the envelope helium abundance to lie in the range 0.231-0.251 for 16 Cyg A and 0.218-0.266 for 16 Cyg B. [ABSTRACT FROM AUTHOR]

High precision photometric observations from space has led to the detection of hundreds of frequencies in the light curves of d Scuti pulsators. In this work, we analyzed a sample of Kepler d Sct stars to search for frequency patterns in the p-mode regime. To avoid g-modes, we looked at the mode density histogram (MDH). We then used the Fourier transform technique (FT), histograms of frequency differences (HFD) and Echelle diagrams (ED) to find periodicities in the frequency content. We compared the results with those expected for SCF rotating models [4] with the aim of identifying large separations and rotational splittings. [ABSTRACT FROM AUTHOR]

In this study, we compare the effect of a modified convection parametrization in solar models on oscillation frequencies with different empirical correction schemes. [ABSTRACT FROM AUTHOR]