38 research outputs found

    Circumnuclear structure and kinematics in the active galaxy NGC 6951

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    A study is presented of the central structure and kinematics of the galaxy NGC 6951, by means of broad band B'IJK images and high resolution high dispersion longslit spectroscopy, together with archival HST WFPC2 V and NICMOS2 J and H images. We find that there is evidence of two modes of star formation, in bursts and continuously. The equivalent width of the CaII triplet absorption lines show that, in the metal rich central region, the continuum is dominated by a population of red supergiants. The gaseous and stellar kinematics along three slit position angles, suggest the existence of a hierarchy of disks within disks, whose dynamics are decoupled at the two ILRs, that we find at 180 pc and at 1100 pc. This is supported by the structure seen in the high resolution HST images. The nucleus is spatially resolved within a radius of 1.5 arcsec, just inside the innermost ILR. Outside the iILR, the stellar CaT velocity profile is resolved into two components, associated with the bar and the disk. Several results indicate that this is a dynamically old system. It is thus possible that a nuclear bar has existed in NGC 6951 that drove the gas towards the nucleus, as in the bars within bars scenario, but that this bar has already dissolved by the gas accumulated within the circumnuclear region. We discuss the possibility that the kinematical component inside the iILR could be due to a nuclear outflow produced by the combined effects of SN and SN remnants, or to a nuclear disk, as in the disk within disk scenario that we propose for the fueling of the AGN in NGC 6951.Comment: 14 pages, 16 figures. Accepted for publication in Astronomy and Astrophysics. High resolution images in http://www.iaa.es/~eperez/research/degas.htm

    Near-infrared photometry of isolated spirals with and without an AGN. I: The Data

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    We present infrared imaging data in the J and K' bands obtained for 18 active spiral galaxies, together with 11 non active galaxies taken as a control sample. All of them were chosen to satisfy well defined isolation criteria so that the observed properties are not related to gravitational interaction. For each object we give: the image in the K' band, the sharp-divided image (obtained by dividing the observed image by a filtered one), the difference image (obtained by subtracting a model to the observed one), the color J-K' image, the ellipticity and position angle profiles, the surface brightness profiles in J and K', their fits by bulge+disk models and the color gradient. We have found that four (one) active (control) galaxies previously classified as non-barred turn out to have bars when observed in the near-infrared. One of these four galaxies (UGC 1395) also harbours a secondary bar. For 15 (9 active, 6 control) out of 24 (14 active, 10 control) of the optically classified barred galaxies (SB or SX) we find that a secondary bar (or a disk, a lense or an elongated ring) is present. The work presented here is part of a large program (DEGAS) aimed at finding whether there are differences between active and non active galaxies in the properties of their central regions that could be connected with the onset of nuclear activity.Comment: Accepted for publication in Astronomy & Astrophysics Supplement Serie

    Near-infrared photometry of isolated spirals with and without an AGN. II: Photometric properties of the host galaxies

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    We present the analysis of morphological and photometric properties of a sample of isolated spirals with (18) and without (11) an active nucleus, based on near-infrared imaging in the J and K' bands. The aim of this analysis is to find the differential properties that could be directly connected with the phenomenon of nuclear activity. We stress the importance of using isolated objects for that purpose. Our study shows that both sets of galaxies are similar in their global properties: they define the same Kormendy relation, their disk components share the same properties, the bulge and disk scale lengths are correlated in a similar way, bar strengths and lengths are similar for primary bars. Hosts of isolated Seyfert galaxies have bulge and disk properties comparable to those of isolated non active spirals. Central colors (the innermost 200 pc) of active galaxies are redder than the centers of non active spirals, most probably due to AGN light being re-emitted by the hot dust and/or due to circumnuclear star formation, through the contribution of giants/supergiants. Only one of the Seyfert galaxies in our sample does not present a primary bar,but both primary and secondary bars are equally present in active and control objects. Secondary central elongations (associated with secondary bars, lenses, rings or disks) may be somewhat different. Numerical models indicate that such secondary bars are not strictly necessary to feed the central engine when a primary bar is present. Our results show that down to scales of 100-300 pc, there are no obvious differences between active and non active spiral galaxies.Comment: 9 pages, accepted for publication in Astronomy and Astrophysic

    Quantities of supplements for grazing beef heifers in the dry-rainy transition season

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    The objective of this study was to evaluate the effect of supplying different quantities of multiple supplements on the nutritional characteristics and productive performance of heifers during the post-weaning phase on Urochloa decumbens pastures during the dry-rainy transition season. Twenty-four heifers (average initial age and weight of 11 mo and 243±6 kg, respectively) were used. The experimental design was completely randomized, with four treatments and six replicates. A supplement containing 25% CP was used, and treatments consisted of the following four levels of supplements: 0, 0.5, 1.0 and 1.5 kg. The animals in the different treatments received a mineral mixture ad libitum. A positive linear effect (P<0.10) was observed on ADG and final body weight with the quantities of supplements. An increasing linear effect (P<0.10) was found on the intakes of DM, OM, CP, EE, NFC and TDN with the elevation in the amount of the supplement provided, which was not observed for NDFap intake. A cubic effect was observed (P<0.10) on the apparent digestibility of OM, CP, NDFap, NFC and concentration of TDN among the quantities of multiple supplements. Supplement levels increased (P<0.10) the digestibility coefficient of EE. An increasing linear response was detected (P<0.10) in urine urea nitrogen excretion, serum urea nitrogen (SUN) and flow of microbial nitrogen (MICN) compounds with the quantities of supplement. No difference was observed (P<0.10) in the efficiency of microbial synthesis between the supplementation levels. The quantities of supplement had a decreasing linear effect (P<0.10) on the relative MICN. In conclusion, supplying higher amounts of multiple supplements during the dry-rainy transition season improves the productive performance and nutritional characteristics of beef heifers reared on pasture.O objetivo do trabalho foi avaliar o efeito do fornecimento de diferentes quantidades de suplementos múltiplos sobre as características nutricionais e desempenho produtivo de novilhas durante a fase de recria em pastagens com Urochloa decumbens no período de transição seca-águas. Foram utilizadas 24 novilhas com idade e peso médio inicial de 11 meses e 243±3 kg, respectivamente. O delineamento foi inteiramente casualizado com quatro tratamentos e seis repetições. Utilizou-se um suplemento com 25% de PB. Os tratamentos consistiam em quatro quantidades de suplementos: 0; 0,5; 1,0 e 1,5 kg respectivamente. Os animais dos diferentes tratamentos receberam mistura mineral ad libitum. Observou-se efeito linear positivo (P<0,10) no GMD e peso corporal final (PCF) com as quantidades de suplementos. Foi verificado efeito linear crescente (P<0,10) no consumo de MS, MO, PB, EE, CNF e NDT com o fornecimento de maiores quantidades de suplemento; efeito não apresentado no consumo de FDNcp. Evidenciou-se efeito cúbico (P<0,10) sobre a digestibilidade aparente da MO, PB, FDNcp, CNF e concentração de NDT entre as quantidades de suplementos múltiplos. As quantidades de suplementos aumentaram (P<0,10) o coeficiente de digestibilidade do EE. Verificou-se comportamento linear crescente (P<0,10) sobre a excreção urinária de nitrogênio uréico (NUU), nitrogênio uréico no soro (NUS) e fluxo de compostos nitrogenados microbianos (NMIC) com as quantidades de suplementos. Não foi observada diferença (P<0,10) das quantidades de suplementação sobre a eficiência de síntese microbiana. As quantidades de suplementos afetaram de forma linear decrescente (P<0,10) o NMICR. Conclui-se que o fornecimento de maiores quantidades de suplementos múltiplos durante a época de transição seca-águas melhora o desempenho produtivo e características nutricionais de novilhas de corte criadas em pastagens

    Slit spectroscopy of nine new

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    We present FWHM=5FWHM = 5 to 8 Å optical spectra of nine previously unknown quasars (QSOs) drawn from the Calan/Tololo Survey. We have chosen this sample based on QSO redshift, z>3z> 3, and the presence of either candidate damped Lyα (DLA) or Lyman-limit (LL) systems in their spectra. The spectra show at least 9 DLA systems at redshifts 2.25<z<3.262.25< z< 3.26, which are identified by the shape and strength of the H

    Takayasu arteritis a cause of hypertensive disorder of pregnancy: a case report

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    Abstract Background Takayasu arteritis is a rare, chronic, granulomatous systemic vasculitis of unknown etiology and a few cases have been reported in pregnancy. In pregnancies concomitant with Takayasu arteritis or after diagnosis, Takayasu arteritis negatively affects pregnancy by increasing 13-fold the odds of complications such as hypertensive disorders. The best recommendations in this scenario are still to be made. Case presentation We present a case of 21-year-old, gravid 1, Mexican woman of Mestizo descent with chronic hypertension diagnosed since she was 15-years old who presented severe hypertension during pregnancy (early second trimester); the diagnosis of hypertensive disorder of pregnancy was ruled out requiring first-line and second-line antihypertensive therapy without serious associated maternal or fetal morbidity. Conclusions Takayasu arteritis and pregnancy play an important role in maternal and fetal outcomes. Efforts should be made to further investigate the Takayasu arteritis diagnosis in pregnant women with refractory hypertension

    Fate of pharmaceutically active compounds in a pilot-scale A<sup>2</sup>O integrated fixed-film activated sludge (IFAS) process treating municipal wastewater

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    The goal of this research was to study the operation of an integrated fixed-film activated sludge system (IFAS), in anaerobic/anoxic/aerobic (A2O) configuration for the elimination of emerging pollutants, in particular of 27 pharmaceutical active compounds (PhACs) (eight anti-inflammatory and/or analgesic pharmaceuticals (AIAPs), six antibiotics, four b-blockers, two antihypertensives/diuretics, three lipid regulators-bezafibrate and four psychiatric medications). Different operational conditions were analyzed in the biological reactor, controlling at all times both the amount of suspended and fixed biomass present. The A2O-IFAS system has obtained similar or higher removal efficiency (RE) in the elimination of organic matter, and especially of nutrients, nitrogen (N) and phosphorous (P), with respect to the conventional A2O system, working however with very low values of the sludge retention time (SRT) (4.0 days) and mix liquid suspended solid (MLSS) in the reactor (1822 mg L-1). In general, conventional activated sludge (CAS) and IFAS processes show the importance of operating at high SRT and MLSS concentration, that give low food/microorganisms (F/M) ratio, to increase the RE of several PhACs. However, the A2O-IFAS system, operating with low mixed liquor SRT and MLSS has achieved similar or better RE of PhACs, obtaining the highest average REs values (>80%) for fenofibrate, acetaminophen, ibuprofen, naproxen, clarithromycin and atenolol. According to the results obtained, due to the affordable cost and well-demonstrated performance, IFAS systems become one of the most promising technology for conventional wastewater treatment plants (WWTP) upgrading.This work was funded by Spanish Ministerio de Economía y Competitividad (MINECO) and Fondo Europeo de Desarrollo Regional (FEDER) (CTM2014-60131-P). MINECO is also acknowledged for personal grants to P. Maza-Márquez (postdoctoral fellow) and M.J. Gallardo-Altamirano (FPI program, BES-2015-073595). Regional Goverment of Murcia, Spain (ESAMUR) and Murcia Water Works (EMUASA) are acknowledged for their collaboration in this research project and provision of facilities at Murcia Este Wastewater Treatment Plant (Murcia, Spain). The authors also acknowledge SCIEX for providing the loan of instrument LC/HRMS QToF X500R.Peer reviewe
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