2 resultados para 763

em Universidade Complutense de Madrid


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We present some of the first science data with the new Keck/MOSFIRE instrument to test the effectiveness of different AGN/SF diagnostics at z ~ 1.5. MOSFIRE spectra were obtained in three H-band multi-slit masks in the GOODS-S field, resulting in 2 hr exposures of 36 emission-line galaxies. We compare X-ray data with the traditional emission-line ratio diagnostics and the alternative mass-excitation and color-excitation diagrams, combining new MOSFIRE infrared data with previous HST/WFC3 infrared spectra (from the 3D-HST survey) and multiwavelength photometry. We demonstrate that a high [O III]/Hβ ratio is insufficient as an active galactic nucleus (AGN) indicator at z > 1. For the four X-ray-detected galaxies, the classic diagnostics ([O III]/Hβ versus [N II]/Hα and [S II]/Hα) remain consistent with X-ray AGN/SF classification. The X-ray data also suggest that "composite" galaxies (with intermediate AGN/SF classification) host bona fide AGNs. Nearly ~2/3 of the z ~ 1.5 emission-line galaxies have nuclear activity detected by either X-rays or the classic diagnostics. Compared to the X-ray and line ratio classifications, the mass-excitation method remains effective at z > 1, but we show that the color-excitation method requires a new calibration to successfully identify AGNs at these redshifts.

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Introduction: No cases of equine infectious anaemia (EIA) have been reported in Spain since 1983. Factors that could increase the risk of reintroducing equine infectious anaemia virus (EIAV) into Spain include the recent occurrence of the disease in Europe and the absence of compulsory serological testing before importation into Spain. Aims and objectives: Given the importance of the Spanish Purebred (SP) horse breeding industry in Spain, the aim of this cross-sectional study was to provide evidence of freedom from EIAV in SP stud farms in Central Spain. Materials and methods: Serum samples from 555 SP horses, collected between September 2011 and November 2013, were tested using a commercially available EIAV ELISA with a published sensitivity of 100 per cent. Results: All 555 samples were negative for antibody to EIAV, providing evidence of a true EIAV seroprevalence between 0 per cent and 0.53 per cent (95% CIs of the sensitivity and specificity of the ELISA technique used Q10 were 100 per cent and 99.3 per cent, respectively) among the SP breeding population in Central Spain. Conclusions: These findings should serve to increase confidence when exporting SP horses to other countries.