Hidden starburst in Seyfert 1 Galaxies

We report the detection of the 3.3 mu Polycyclic Aromatic Hydrocarbon (PAH) feature in two Seyfert 1 galaxies - NGC 3227 and Mrk 766, and one QSO - Mrk 478, observed with SpeX at IRTF at a spectral resolution not previously attained for this type of objects. Except for NGC 3227, this is the first time that the 3.3 mu PAH emission is detected in Mrk 766 and Mrk 478. The widths of the emission, reported also for the first time, are rather similar, ranging from 450 A to 550 A. The luminosity of the 3.3 mu PAH emission measured in the QSO Mrk 478 places it at a level similar of that found in starburst and infrared luminous galaxies and implies that this object is having a vigorous burst of star formation. The spatial resolution of the spectra allows us to constrain the location of the star-forming region to the inner 1 Kpc for the QSO and 150 pc for the Seyferts. Our results support the idea that these objects resides in molecular gas-rich galaxies and that their observed infrared excess is primarily due to star formation, as previously indicated by CO and H_2 observations. We also report, for Mrk 1239, the presence of a broad emission feature centred at 3.43 mu, not previosly detected in an extragalactic object and whose origin is not yet clear.Comment: 5 pages, 1 figure. Accepted to MNRAS pink page

The Infrared-X-ray continuum correlation in Active Galactic Nuclei

The correlation between the soft X-ray and near infrared emission from AGN is analysed using composite models by the code SUMA. We find new evidences for differences in ranges of parameters which characterize the NLR of Seyfert galaxies and LINERs. Results obtained by modelling the Einstein and the ROSAT samples of galaxies are in full agreement. In order to fit the infrared and X-ray continua, an eta factor is defined, which accounts for the emitting area of the cloud. If the infrared emission is due to bremsstrahlung and comes from the same cloud producing the soft X-rays, the eta values obtained from both emissions must be the same. Therefore, if eta_IR < eta_soft-X there must be a strong contribution of soft X-rays from the active centre. From the eta values we expect to identify the objects that could present strong variability. \Comment: 11 pages,13 figures, in press in MNRAS. in press in MNRA

Extended Coronal Emission Lines in Active Galactic Nuclei

VLT and NTT spectra are used to examine the nuclear and extended coronal line emission in a sample of well-known Seyfert 1 and 2 galaxies. The excellent spatial resolution obtained with VLT allowed us to map [SiVI] 1.963 $\mu$m and [SiVII] 2.48 $\mu$m on scales of up to 20 pc. Coronal line emission, extended to distances of $\sim$100 pc, is detected in some of the lines analyzed, particularly in [FeX] 6374\AA, [FeXI] 7891\AA, and [SiVII] 2.48$\mu$m. Most coronal lines are strongly asymmetric towards the blue and broader than low-ionization lines. This result is particularly important for Circinus, where previous observations had failed at detecting larger widths for high-ionization lines. Photoionization models are used to investigate the physical conditions and continuum luminosities necessary to produced the observed coronal emission. We found that an ionization parameter U> 0.10 is necessary to reproduce the observations, although the clouds should be located at distances < 30 pc.Comment: 4 pages, 6 figures, to appear in proceedings of IAU Symposium No. 222, The Interplay Among Black Holes, Stars and ISM in Galacti Nucle

Occupational Exposure to Mycotoxins: Current Knowledge and Prospects.

Occupational exposure to mycotoxins is supposedly very frequent, but it is rarely reported in the scientific literature. Several recent studies described occupational exposure to the aflatoxin B1 (AFB1) mycotoxin in different occupational settings. Previously, exposure to other mycotoxins was shown in the animal husbandry and food processing sectors, confirming that occupational exposure cannot be negligible. However, no guidelines or standard methodologies are available for helping occupational hygienists to consider mycotoxin exposure in their interventions. This article reviews the literature on this problem and recommends some actions for the better management of this risk factor in occupational settings, especially where environmental conditions are favorable to fungal presence

One Health approach for the SDGs achievement

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Biodiversity and Health

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