2,589 research outputs found
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
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 m and
[SiVII] 2.48 m on scales of up to 20 pc. Coronal line emission, extended
to distances of 100 pc, is detected in some of the lines analyzed,
particularly in [FeX] 6374\AA, [FeXI] 7891\AA, and [SiVII] 2.48m. 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
A methodological approach in order to support decision-makers when defining Mobility and Transportation Politics
Nowadays Portugal is under a large process of creation/revision of studies and plans related with land use and territorial planning, mainly due to the end of the lifetime period of the actual Municipal Master Plan, but also because of the creation of the new Metropolitan Authorities of Transportation, which will require Mobility Plans. Even though the Portuguese law doesnât impose these Mobility Plans at the present moment, there is a general feeling about the importance of the mobility system for the society and economics in general. This is the case in highly density areas, where the need and complexity of the system requires these specific studies in order to obtain an efficient management; or in the case of low-density areas where the risk of loosing competitiveness is too high to ignore the importance of the transportation and mobility system, and the advantage of gaining local and regional competitiveness might increase the importance of the municipality in regional context. This paper intends to provide an innovative approach regarding the provision, at an early stage, of technical support to decision-makers in order to define Mobility and Transportation Policies. The opportunity provided by using adapted SWOT analysis (among others) to identify weakening or potential factors, and how to take advantage of the results, always using a cause and effect approach and a coherent policy in order to obtain high quality and effective studies and politics. The methodology relies on a two-stage process. In the first stage a summary diagnose is provided, using inputs which are supposed to well characterise the territoryâs mobility patterns. Afterwards, in a second phase, these are inter-related and evaluated in order to build-up a table of options, where policies are proposed with a careful attention to its qualitative cross impact with the measures and objectives intended to be achieved. The proposed methodology was applied in the AlcobaçaÂŽs Municipality case study, which provided different lines of action in diverse subjects, such as, public and private transportation networks, parking policies and organisation, and territory competitiveness. This study was particularly relevant, since this Municipality is under great pressure of its neighbour municipalities, has a low level of regional importance and a low intra-municipal cohesion. Finally, the general opinion of the decision-makers about this technical approach is presented. Keywords: Mobility; Transportation; Land Planning and Policies; Decision-making Support
Marine 5-thiohistidines as protective molecules from skin damage
Introduction Marine environment is a great source of bioactive molecules, whose biological properties and applications are often used especially to prevent skin diseases
and aging caused by UVAÂexposure. Ovothiols are methylÂ5Âthiohistidines from marine invertebrates, bacteria, and microalgae, which protect cells from environmental
stressors. Recently, we have shown that, ovothiol, isolated from sea urchin eggs, exerts antiÂinflammatory and antioxidant activities on human endothelial cells, and
exhibits antifibrotic effect in an in vivo model of liver fibrosis.info:eu-repo/semantics/publishedVersio
Volatile Organic Compounds in Healthcare facilities - A study developed in Primary Healthcare Centers in Lisbon
Trabalho apresentado em International Conference in Environmental Health - ICEH2019, 2019, Lisboa, PortugalN/
Accessing occupational exposure to fungi in a cork industry
In this study we aimed to access fungal exposure in workers from one cork industry through the mycological
analysis of their nasal exudate and the environmental fungal contamination of their surroundings as well.
Nasal mucous samples from 127 workers were taken with sterilized cotton swabs.The fungal species identified in the collected nose swabs were shown to be correlated with the results obtained in the environment. Eighty workers (63.0%) presented contamination of their nose nostril with Chrysonilia sitophila, which number of colonies was
countless. Within the Aspergillus genus, the complexes Fumigati, Circumdati, Versicolores and Candidi were isolated. No azole-resistant Aspergillus isolates grew in the selective media used
(screened itraconazole and voriconazole resistance).This approach allowed us to estimate the risk associated with these tasks performance. Moreover, the cork industry is related to high dust contamination and this can promote exposure to fungi since dust particles can act as carriers of fungi to the workerâs nose. Assessment by molecular tools will ensure the specific targeting of DNA from P. glabrum complex in workers nose
Comparison of indoor and outdoor fungi and particles in poultry units
A descriptive study was developed in order to compare indoor and outdoor air contamination caused by fungi and particles in seven poultry units. Twenty eight air samples of 25 litters were collected through the impaction method on malt extract agar.
Air sampling and particles concentration measurement were done in the interior and also outside premises of the poultriesâ pavilions. Regarding the fungal load in the air, indoor concentration of mold was higher than outside air in six poultry units. Twenty eight species / genera of fungi were identified indoor, being Scopulariopsis brevicaulis (40.5%) the most commonly isolated species and Rhizopus sp. (30.0%) the most commonly isolated genus. Concerning outdoor, eighteen species/genera of fungi were isolated, being Scopulariopsis brevicaulis (62.6%) also the most isolated.
All the poultry farms analyzed presented indoor fungi different from the ones identified outdoors. Regarding particlesâ contamination, PM2.5, PM5.0 and PM10 had a statistically significant difference (Mann-Whitney U test) between the inside and outside of the pavilions, with the inside more contaminated (p=.006; p=.005; p=.005, respectively). The analyzed poultry units are potential reservoirs of substantial amounts of fungi and particles and could therefore free them in the atmospheric air.
The developed study showed that indoor air was more contaminated than outdoors, and this can result in emission of potentially pathogenic fungi and particles via aerosols from poultry units to the environment, which may post a considerable risk to public health and contribute to environmental pollution
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