This is the second in a series of papers devoted to exploring a set of six dusty models of active galactic nuclei (AGN) with available spectral energy distributions. These models are the smooth torus ...by Fritz et al., the clumpy torus by Nenkova et al., the clumpy torus by Hönig & Kishimoto, the two-phase torus by Siebenmorgen et al., the two-phase torus by Stalevski et al., and the wind model by Hönig & Kishimoto. The first paper explores discrimination among models and the parameter restriction using synthetic spectra. Here we perform spectral fitting of a sample of 110 AGN drawn from the Swift/BAT survey with Spitzer/IRS spectroscopic data. The aim is to explore which is the model that describes better the data and the resulting parameters. The clumpy wind-disk model by Hönig & Kishimoto provides good fits for ∼50% of the sample, and the clumpy torus model by Nenkova et al. is good at describing ∼30% of the objects. The wind-disk model by Hönig & Kishimoto is better for reproducing the mid-infrared spectra of type 1 Seyferts (with 60% of the type 1 Seyferts well reproduced by this model compared to the 10% well represented by the clumpy torus model by Nenkova et al.), while type 2 Seyferts are equally fitted by both models (roughly 40% of the type 2 Seyferts). Large residuals are found irrespective of the model used, indicating that the AGN dust continuum emission is more complex than predicted by the models or that the parameter space is not well sampled. We found that all the resulting parameters for our AGN sample are roughly constrained to 10%-20% of the parameter space. Contrary to what is generally assumed, the derived outer radius of the torus is smaller (reaching up to a factor of ∼5 smaller for 10 pc tori) for the smooth torus by Fritz et al. and the two-phase torus by Stalevski et al. than the one derived from the clumpy torus by Nenkova et al. Covering factors and line-of-sight viewing angles strongly depend on the model used. The total dust mass is the most robust derived quantity, giving equivalent results for four of these models.
Abstract
We present a study of the O
iii
λ
5007 line profile in a subsample of eight active galactic nuclei (AGNs) and six non-AGNs in the optically selected green valley at
z
< 0.5 using long-slit ...spectroscopic observations obtained with the 11 m Southern African Large Telescope. Gaussian decomposition of the line profile was performed to study its different components. We observe that the AGN profiles are more complex than the non-AGN ones. In particular, in most AGNs (5/8) we detect a blue wing of the line. We derive the FWHM velocities of the wing and systemic component, and find that the AGNs show higher FWHM velocities than the non-AGNs in their core component. We also find that the AGNs show blue wings with a median velocity width of approximately 600 km s
−1
, and a velocity offset from the core component in the range −90 to −350 km s
−1
, in contrast to the non-AGN galaxies, where we do not detect blue wings in any of their O
iii
λ
5007 line profiles. Using the spatial information in our spectra, we show that at least three of the outflow candidate galaxies have centrally driven gas outflows extending across the whole galaxy. Moreover, these are also the galaxies which are located on the main sequence of star formation, raising the possibility that the AGNs in our sample are influencing the star formation of their host galaxies (such as positive feedback). This is in agreement with our previous work where we studied the star formation, morphology, and stellar population properties of a sample of green valley AGNs and non-AGN galaxies.
European eel (Anguilla anguilla) populations have declined drastically over the last decades and it has been included in the IUCN red list of endangered species as critically endangered since 2007. ...Thus, continuous population monitoring is crucial in order to warrant the conservation of this emblematic species.
Environmental DNA (eDNA) has been recently implemented as a powerful method for the detection and monitoring of freshwater species, particularly for endangered species, where eDNA methods have shown to be less invasive than other methods (e.g. electrofishing).
In this study, we developed and validated, under controlled conditions, a new species-specific tool for detecting A. anguilla from water samples by means of eDNA. Furthermore, we applied a semi-quantitative approach for monitoring of glass eel at different depths (surface and bottom) during different seasons in two rivers of northern Spain (Nalón and Sella rivers). We detected a significantly higher proportion of positive DNA amplifications in bottom than surface samples. Moreover, the proportion of replicas with positive amplification varied along the estuaries sections examined, and especially in the different sampling months. The temporal detection trends found in this study were compatible with the known upstream migration pattern of this species.
Altogether, this study contributes to the establishment of a simple, easy and cheap system based on eDNA, that could be routinely applied in conservation research and management programs to monitoring wild populations of endangered species.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
At distances from the active galaxy nucleus where the ambient temperature falls below ∼1500-1800 K, dust is able to survive. It is thus possible to have a large dusty structure present that surrounds ...the active galaxy nucleus. This is the first of two papers aiming at comparing six dusty torus models with available spectral energy distributions, namely, Fritz et al., Nenkova et al., Hönig & Kishimoto, Siebenmorgen et al., Stalevski et al., and Hönig & Kishimoto. In this first paper we use synthetic spectra to explore the discrimination between these models and under which circumstances they allow us to restrict the torus parameters, while our second paper analyzes the best model to describe the mid-infrared spectroscopic data. We have produced synthetic spectra from current instruments GTC/CanariCam and Spitzer/IRS and future James Webb Space Telescope (JWST)/MIRI and JWST/NIRSpec instruments. We find that for a reasonable brightness (F12 m > 100 mJy) we can actually distinguish among models except for the two pairs of parent models. We show that these models can be distinguished based on the continuum slopes and the strength of the silicate features. Moreover, their parameters can be constrained within 15% of error, irrespective of the instrument used, for all the models except Hönig & Kishimoto. However, the parameter estimates are ruined when more than 50% of circumnuclear contributors are included. Therefore, future high spatial resolution spectra such as those expected from JWST will provide enough coverage and spatial resolution to tackle this topic.
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•Heat flux evaluated numerically with a 1D inverse heat conduction problem.•Time-varying upper boundary condition reproducing paleoclimate events.•Temperature and pressure-dependent ...thermal conductivity considered in the model.•Heat flux in the range 31.8 – 69.4 mW m−2 depending on paleoclimate and thermophysical properties conditions.•Low-cost method to help advancing geothermal exploration in remote northern regions.
Assessing the geothermal potential in remote northern regions is challenging. First, due to remoteness and, second, due to data gaps. Often, Earth heat flux is inferred from deep equilibrium temperature profiles. However, in remote areas where deep boreholes are nonexistent, an adapted methodology is needed. Therefore, this study presents a new versatile and reliable numerical approach that simulates climate events and infers heat flux from a shallow temperature profile (80 m depth). Thus, addressing the challenge linked with heat flux assessment in northern regions and offering an original contribution to advance geothermal research in remote areas facing energy development challenges.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
ABSTRACT
We present X-ray and optical properties of the optically confirmed galaxy cluster sample from the 3XMM/SDSS Stripe 82 cluster survey. The sample includes 54 galaxy clusters in the redshift ...range of 0.05–1.2, with a median redshift of 0.36. We first present the X-ray temperature and luminosity measurements that are used to investigate the X-ray luminosity–temperature relation. The slope and intercept of the relation are consistent with those published in the literature. Then, we investigate the optical properties of the cluster galaxies including their morphological analysis and the galaxy luminosity functions (GLFs). The morphological content of cluster galaxies is investigated as a function of cluster mass and distance from the cluster centre. No strong variation of the fraction of early- and late-type galaxies with cluster mass is observed. The fraction of early-type galaxies as a function of cluster radius varies as expected. The individual GLFs of red sequence galaxies were studied in the five ugriz bands for 48 clusters. The GLFs were then stacked in three mass bins and two redshift bins. Twenty clusters of the present sample are studied for the first time in X-rays, and all are studied for the first time in the optical range. Altogether, our sample appears to have X-ray and optical properties typical of ‘average’ cluster properties.
Several authors have claimed that less luminous active galactic nuclei (AGNs) are not capable of sustaining a dusty torus structure. Thus, a gradual resizing of the torus is expected when the AGN ...luminosity decreases. Our aim is to examine mid-infrared observations of local AGNs of different luminosities for the gradual resizing and disappearance of the torus. We applied the decomposition method described by Hernán-Caballero et al. to a sample of ∼100 Spitzer/IRS spectra of low-luminosity AGNs and powerful Seyferts in order to decontaminate the torus component from other contributors. We have also included Starburst objects to ensure secure decomposition of the Spitzer/IRS spectra. We have used the affinity propagation (AP) method to cluster the data into five groups within the sample according to torus contribution to the 5-15 m range ( ) and bolometric luminosity ( ). The AP groups show a progressively higher torus contribution and an increase of the bolometric luminosity from Group 1 ( and ) up to Group 5 ( and ). We have fitted the average spectra of each of the AP groups to clumpy models. The torus is no longer present in Group 1, supporting its disappearance at low luminosities. We were able to fit the average spectra for the torus component in Groups 3 ( and ), 4 ( and ), and 5 to Clumpy torus models. We did not find a good fitting to Clumpy torus models for Group 2 ( and ). This might suggest a different configuration and/or composition of the clouds for Group 2, which is consistent with the different gas content seen in Groups 1, 2, and 3, according to detections of molecular lines. Groups 3, 4, and 5 show a trend of decreasing torus width (which leads to a likely decrease of the geometrical covering factor), although we cannot confirm it with the present data. Finally, Groups 3, 4, and 5 show an increase of the outer radius of the torus for higher luminosities, consistent with a resizing of the torus according to AGN luminosity.
ABSTRACT
This paper presents new optical and near-UV spectra of 11 extremely powerful jetted quasars, with radio to optical flux density ratio >103, which concomitantly cover the low-ionization ...emission of Mg iiλ2800 and hβ as well as the Fe ii blends in the redshift range 0.35 ≲ z ≲ 1. We aim to quantify broad emission line differences between radio-loud (RL) and radio-quiet (RQ) quasars by using the 4D eigenvector 1 parameter space and its main sequence (MS) and to check the effect of powerful radio ejection on the low-ionization broad emission lines. The hβ and Mg iiλ2800 emission lines were measured by using non-linear multicomponent fittings as well as by analysing their full profile. We found that broad emission lines show large redward asymmetry both in hβ and Mg iiλ2800. The location of our RL sources in a UV plane looks similar to the optical one, with weak Fe iiUV emission and broad Mg iiλ2800. We supplement the 11 sources with large samples from previous work to gain some general inferences. We found that, compared to RQ, our extreme RL quasars show larger median hβ full width at half maximum (FWHM), weaker Fe ii emission, larger MBH, lower Lbol/LEdd, and a restricted bf space occupation in the optical and UV MS planes. The differences are more elusive when the comparison is carried out by restricting the RQ population to the region of the MS occupied by RL sources, albeit an unbiased comparison matching MBH and Lbol/LEdd suggests that the most powerful RL quasars show the highest redward asymmetries in hβ.
Leishmaniasis is a neglected disease, World Health Organization (WHO) declared it as high priority worldwide. Colombia is one of the 98 countries in which the disease caused more than 17.000 cases ...per year. There is a need to explore novel therapies to reduce the side effects of the current treatments. For this reason, this study was aimed to evaluate Galleria mellonella hemolymph for potential peptides with anti-parasitic activity. Larvae were challenged with Leishmania (V) panamensis promastigotes and hemolymph was analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), reversed-phase chromatography (RP-HPLC), two-dimensional gel electrophoresis and liquid chromatography-mass spectroscopy (LC/MS). The immunological response of Galleria mellonella was followed by SDS-PAGE, immunized hemolymph was fractionated by RP-HPLC where fractions 5 and 11 showed the highest antileishmanial activity. From these fractions 15 spots were isolated by 2D gel electrophoresis and evaluated by LC/MS to identify the peptides present in the spots. After the analysis Moricin-B, Moricin-C4, Cecropin-D and Anionic Peptide 2 were identified due to the immune challenge with Leishmania promastigotes. Anionic peptide 2 and Cecropin-D were synthesized and evaluated for antileishmanial activity. The results showed that Anionic peptide 2 presented more anti-parasitic activity. This study showed for the first time the anti-parasitic potential of peptides derived from hemolymph of Galleria mellonella.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
This work presents the properties of 42 objects in the group of the most luminous, highest star formation rate (SFR) low-ionization nuclear emission-line regions (LINERs) at z = 0.04–0.11. We ...obtained long-slit spectroscopy of the nuclear regions for all sources, and FIR data (Herschel and IRAS) for 13 of them. We measured emission-line intensities, extinction, stellar populations, stellar masses, ages, active galactic nuclei (AGN) luminosities, and SFRs. We find considerable differences from other low-redshift LINERs, in terms of extinction, and general similarity to star-forming galaxies. We confirm the existence of such luminous LINERs in the local universe, after being previously detected at z ∼ 0.3 by Tommasin et al. The median stellar mass of these LINERs corresponds to 6–7 × 1010 M⊙ which was found in previous work to correspond to the peak of relative growth rate of stellar populations and therefore for the highest SFRs. Other LINERs although showing similar AGN luminosities have lower SFR. We find that most of these sources have LAGN ∼ LSF suggesting co-evolution of black hole and stellar mass. In general, the fraction of local LINERs on the main sequence of star-forming galaxies is related to their AGN luminosity.
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