177 research outputs found
A Comparative Electrochemical-Ozone Treatment for Removal of Phenolphthalein
The degradation of aqueous solutions containing phenolphthalein was carried out using ozone and electrochemical processes; the two different treatments were performed for 60 min at pH 3, pH 7, and pH 9. The electrochemical oxidation using boron-doped diamond electrodes processes was carried out using three current density values: 3.11 mAâ
cm â2 , 6.22 mAâ
cm â2 , and 9.33 mAâ
cm â2 , whereas the ozone dose was constantly supplied at 5 ± 0.5 mgL â1 . An optimal degradation condition for the ozonation treatment is at alkaline pH, while the electrochemical treatment works better at acidic pH. The electrochemical process is twice better compared with ozonation
First survey of Wolf-Rayet star populations over the full extension of nearby galaxies observed with CALIFA
The search of extragalactic regions with conspicuous presence of Wolf-Rayet
(WR) stars outside the Local Group is challenging task due to the difficulties
in detecting their faint spectral features. In this exploratory work, we
develop a methodology to perform an automated search of WR signatures through a
pixel-by-pixel analysis of integral field spectroscopy (IFS) data belonging to
the Calar Alto Legacy Integral Field Area survey, CALIFA. This technique
allowed us to build the first catalogue of Wolf-Rayet rich regions with
spatially-resolved information, allowing to study the properties of these
complexes in a 2D context. The detection technique is based on the
identification of the blue WR bump (around He II 4686 {\AA}, mainly associated
to nitrogen-rich WR stars, WN) and the red WR bump (around C IV 5808 {\AA} and
associated to carbon-rich WR stars, WC) using a pixel-by-pixel analysis. We
identified 44 WR-rich regions with blue bumps distributed in 25 galaxies of a
total of 558. The red WR bump was identified only in 5 of those regions. We
found that the majority of the galaxies hosting WR populations in our sample
are involved in some kind of interaction process. Half of the host galaxies
share some properties with gamma-ray burst (GRB) hosts where WR stars, as
potential candidates to being the progenitors of GRBs, are found. We also
compared the WR properties derived from the CALIFA data with stellar population
synthesis models, and confirm that simple star models are generally not able to
reproduce the observations. We conclude that other effects, such as the binary
star channel (which could extend the WR phase up to 10 Myr), fast rotation or
other physical processes that causes the loss of observed Lyman continuum
photons, are very likely affecting the derived WR properties, and hence should
be considered when modelling the evolution of massive stars.Comment: 33 pages, accepted for publication in A&
A characteristic oxygen abundance gradient in galaxy disks unveiled with CALIFA
The authors thank the Viabilidad, Diseño, Acceso y Mejorafunding program, ICTS-2009-10, for supporting the initial development of this project. S.F.S., F.F.R.O. and D. Mast thank the Plan Nacional de InvestigaciĂłn y Desarrollo funding programs, AYA2010-22111-C03-03 and AYA2010-10904E, of the Spanish Ministerio de Ciencia e InnovaciĂłn, for their support for this project. S.F.S thanks the RamĂłn y Cajal project RyC-2011-07590 of the Spanish Ministerio de EconomĂa y Competitividad, for their support for this project. S.F.S. and B.J. acknowledge support from the grants No. M100031241 and M100031201 of the Academy of Sciences of the Czech Republic (ASCR Internal support program of international cooperation projects â PIPPMS) and by the Czech Republic program for the long-term development of the research institution No. RVO67985815. R.G.D., E.P., and R.G.B. thank the Plan Nacional de InvestigaciĂłn y Desarrollo funding program AYA2010-15081. F.F.R.O. acknowledges the Mexican National Council for Science and Technology (CONACYT) for financial support under the program Estancias Posdoctorales y SabĂĄticas al Extranjero para la ConsolidaciĂłn de Grupos de InvestigaciĂłn, 2010-2012. I.M. and J.P. acknowledge financial support from the Spanish grant AYA2010-15169 and Junta de AndalucĂa TIC114 and Excellence Project P08-TIC-03531. D.M. and A.M.-I. are supported by the Spanish Research Council within the program JAE-Doc, Junta para la AmpliaciĂłn de Estudios, cofunded by the FSE. R.A. Marino was also funded by the Spanish program of the International Campus of Excellence Moncloa (CEI). J.I.-P., J.M.V., A.M.-I., and C.K. have been partially funded by the projects AYA2010-21887 from the Spanish PNAYA, CSD2006 â 00070 â1st Science with GTCâ from the CONSOLIDER 2010 program of the Spanish MICINN, and TIC114 Galaxias y CosmologĂa of the Junta de AndalucĂa (Spain). M.A.P.T. acknowledges support by the Spanish MICINN through grant AYA2012-38491-C02-02 and by the Autonomic Government of Andalusia through grants P08-TIC-4075 and TIC-126. CJW acknowledges support through the Marie Curie Career Integration Grant 303912. Polychronis Papaderos is supported by a Ciencia 2008 contract, funded by FCT/MCTES (Portugal) and POPH/FSE (EC). Jean Michel Gomes is supported by a grant SFRH/BPD/66958/2009 from FCT (Portugal).We present the largest and most homogeneous catalog of H II regions and associations compiled so far. The catalog comprises more than 7000 ionized regions, extracted from 306 galaxies observed by the CALIFA survey. We describe the procedures used to detect, select, and analyze the spectroscopic properties of these ionized regions. In the current study we focus on characterizing of the radial gradient of the oxygen abundance in the ionized gas, based on the study of the deprojected distribution of H II regions. We found that all galaxies without clear evidence of an interaction present a common gradient in the oxygen abundance, with a characteristic slope of aO/H = -0.1 dex/re between 0.3 and 2 disk effective radii (re), and a scatter compatible with random fluctuations around this value, when the gradient is normalized to the disk effective radius. The slope is independent of morphology, the incidence of bars, absolute magnitude, or mass. Only those galaxies with evidence of interactions and/or clear merging systems present a significantly shallower gradient, consistent with previous results. The majority of the 94 galaxies with H II regions detected beyond two disk effective radii present a flattening in the oxygen abundance. The flattening is statistically significant. We cannot provide a conclusive answer regarding the origin of this flattening. However, our results indicate that its origin is most probably related to the secular evolution of galaxies. Finally, we find a drop/truncation of the oxygen abundance in the inner regions for 26 of the galaxies. All of them are non-interacting, mostly unbarred Sb/Sbc galaxies. This feature is associated with a central star-forming ring, which suggests that both features are produced by radial gas flows induced by resonance processes. Our result suggests that galaxy disks grow inside-out, with metal enrichment driven by the local star formation history and with a small variation galaxy-by-galaxy. At a certain galactocentric distance, the oxygen abundance seems to be correlated well with the stellar mass density and total stellar mass of the galaxies, independently of other properties of the galaxies. Other processes, such as radial mixing and inflows/outflows seem to have a limited effect on shaping of the radial distribution of oxygen abundances, although they are not ruled out.Peer reviewe
Metabolic flux analysis and the NAD(P)H/NAD(P) + ratios in chemostat cultures of Azotobacter vinelandii
Azotobacter vinelandii is a bacterium that produces alginate and polyhydroxybutyrate (P3HB); however, the role of NAD(P)H/NAD(P) + ratios on the metabolic fluxes through biosynthesis pathways of these biopolymers remains unknown. The aim of this study was to evaluate the NAD(P)H/NAD(P) + ratios and the metabolic fluxes involved in alginate and P3HB biosynthesis, under oxygen-limiting and non-limiting oxygen conditions. The results reveal that changes in the oxygen availability have an important effect on the metabolic fluxes and intracellular NADPH/NADP + ratio, showing that at the lowest OTR (2.4 mmol L â1 h â1), the flux through the tricarboxylic acid (TCA) cycle decreased 27.6-fold, but the flux through the P3HB biosynthesis increased 6.6-fold in contrast to the cultures without oxygen limitation (OTR = 14.6 mmol L â1 h â1). This was consistent with the increase in the level of transcription of phbB and the P3HB biosynthesis. In addition, under conditions without oxygen limitation, there was an increase in the carbon uptake rate (twofold), as well as in the flux through the pentose phosphate (PP) pathway (4.8-fold), compared to the condition of 2.4 mmol L â1 h â1. At the highest OTR condition, a decrease in the NADPH/NADP + ratio of threefold was observed, probably as a response to the high respiration rate induced by the respiratory protection of the nitrogenase under diazotrophic conditions, correlating with a high expression of the uncoupled respiratory chain genes (ndhII and cydA) and induction of the expression of the genes encoding the nitrogenase complex (nifH). We have demonstrated that changes in oxygen availability affect the internal redox state of the cell and carbon metabolic fluxes. This also has a strong impact on the TCA cycle and PP pathway as well as on alginate and P3HB biosynthetic fluxes
Pipe3d, a pipeline to analyze integral field spectroscopy data: II Analysis sequence and califa dataproducts
Presentamos una version mejorada de FIT3D, una herramienta de ajuste para el analisis de las poblaciones estelares y el gas ionizado en espectros de galaxias de resolucion intermedia. La misma se desarrollo para el anĂĄlisis de datos de espectroscopĂa de campo integral y es la base de Pipe3D, un dataducto usado en el analisis de datos de los muestreos CALIFA, MaNGA y SAMI. Describimos la filosofŽıa y los pasos seguidos en el ajuste, presentando un conjunto amplio de simulaciones con el fin de estimar la precisiĂłn de los parametros derivados, mostrando el resultado de dichas simulaciones. Finalmente, comparamos el resultado del analisis con FIT3D y el obtenido mediante otros paquetes de uso frecuente, encontrando que los parametros derivados son totalmente compatibles.We present Pipe3D, an analysis pipeline based on the FIT3D fitting tool, developed to explore the properties of the stellar populations and ionized gas of integral field spectroscopy (IFS) data. Pipe3D was created to provide coherent, simple to distribute, and comparable dataproducts, independently of the origin of the data, focused on the data of the most recent IFU surveys (e.g., CALIFA, MaNGA, and SAMI), and the last generation IFS instruments (e.g., MUSE). In this article we describe the di fferent steps involved in the analysis of the data, illustrating them by showing the dataproducts derived for NGC 2916, observed by CALIFA and P-MaNGA. As a practical example of the pipeline we present the complete set of dataproducts derived for the 200 datacubes that comprises the V500 setup of the CALIFA Data Release 2 (DR2), making them freely available through the network. Finally, we explore the hypothesis that the properties of the stellar populations and ionized gas of galaxies at the e ffective radius are representative of the overall average ones, finding that this is indeed the case.Fil: SĂĄnchez, S. F.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MĂ©xicoFil: PĂ©rez, E.. Instituto de AstrofĂsica de AndalucĂa; España. Consejo Superior de Investigaciones CientĂficas; EspañaFil: Sanchez Blazquez, P.. Departamento de Fisica Teorica ; Facultad de Ciencias ; Universidad Autonoma de Madrid;Fil: GarcĂa Benito, RubĂ©n. Instituto de AstrofĂsica de AndalucĂa; España. Consejo Superior de Investigaciones CientĂficas; EspañaFil: Ibarra Mede, H. J.. Space Telescope Science Institute; Estados UnidosFil: GonzĂĄlez, J. J.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MĂ©xicoFil: Rosales Ortega, F. F.. Instituto Nacional de AstrofĂsica, Optica y ElectrĂłnica
; MĂ©xicoFil: SĂĄnchez Menguiano, L.. Instituto de AstrofĂsica de AndalucĂa; España. Consejo Superior de Investigaciones CientĂficas; EspañaFil: Ascasibar, Y.. Universidad AutĂłnoma de Barcelona. Facultad de FĂsica. Departamento AstronomĂa y MeteorologĂa; EspañaFil: Bitsakis, T.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MĂ©xicoFil: Law, D.. Space Telescope Science Institute; Estados UnidosFil: Cano DĂaz, M.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MĂ©xicoFil: LĂłpez CobĂĄ, C.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MĂ©xicoFil: Marino, R. A.. Universidad Complutense de Madrid; EspañaFil: Gil de Paz, A.. Australian Astronomical Observatory; AustraliaFil: LĂłpez SĂĄnchez, A.. Instituto de AstrofĂsica de Canarias (iac); EspañaFil: Barrera Ballesteros, Jorge K.. Instituto de AstrofĂsica de Canarias; EspañaFil: Galbany, LluĂs. Millennium Institute Of Astrophysics; Chile. Universidad de Chile; ChileFil: Mast, Damian. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de AstronomĂa TeĂłrica y Experimental. Universidad Nacional de CĂłrdoba. Observatorio AstronĂłmico de CĂłrdoba. Instituto de AstronomĂa TeĂłrica y Experimental; ArgentinaFil: Abril Malgarejo, V.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MĂ©xicoFil: Roman Lopes, A.. Universidad de La Serena; Chil
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
CALIFA, the Calar Alto Legacy Integral Field Area survey III. Second public data release
CALIFA is the first legacy survey being performed at Calar Alto. The CALIFA collaboration would like to thank the IAA-CSIC and MPIA-MPG as major partners of the observatory, and CAHA itself, for the unique access to telescope time and support in manpower and infrastructures. The CALIFA collaboration thanks also the CAHA staff for the dedication to this project. R.G.B., R.G.D., and E.P. are supported by the Spanish Ministerio de Ciencia e Innovacion under grant AYA2010-15081. S.Z. is supported by the EU Marie Curie Integration Grant "SteMaGE" Nr. PCIG12-GA-2012-326466 (Call Identifier: FP7-PEOPLE-2012 CIG). J.F.B. acknowledges support from grants AYA2010-21322-C03-02 and AIB-2010-DE-00227 from the Spanish Ministry of Economy and Competitiveness (MINECO), as well as from the FP7 Marie Curie Actions of the European Commission, via the Initial Training Network DAGAL under REA grant agreement number 289313. Support for L.G. is provided by the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC12009, awarded to The Millennium Institute of Astrophysics, M.A.S.L.G. also acknowledges support by CONICYT through FONDECYT grant 3140566. A.G. acknowledges support from the FP7/2007-2013 under grant agreement n. 267251 (AstroFIt). J.M.G. acknowledges support from the Fundacao para a Ciencia e a Tecnologia (FCT) through the Fellowship SFRH/BPD/66958/2009 from FCT (Portugal) and research grant PTDC/FIS-AST/3214/2012. RAM was funded by the Spanish programme of International Campus of Excellence Moncloa (CEI). J.M.A. acknowledges support from the European Research Council Starting Grant (SEDmorph; P.I. V. Wild). I.M., J.M. and A.d.O. acknowledge the support by the projects AYA2010-15196 from the Spanish Ministerio de Ciencia e Innovacion and TIC 114 and PO08-TIC-3531 from Junta de Andalucia. AMI acknowledges support from Agence Nationale de la Recherche through the STILISM project (ANR-12-BS05-0016-02). M.M. acknowledges financial support from AYA2010-21887-C04-02 from the Ministerio de Economia y Competitividad. P.P. is supported by an FCT Investigador 2013 Contract, funded by FCT/MCTES (Portugal) and POPH/FSE (EC). P.P. acknowledges support by FCT under project FCOMP-01-0124-FEDER-029170 (Reference FCT PTDC/FIS-AST/3214/2012), funded by FCT-MEC (PIDDAC) and FEDER (COMPETE). T.R.L. thanks the support of the Spanish Ministerio de Educacion, Cultura y Deporte by means of the FPU fellowship. PSB acknowledges support from the Ramon y Cajal program, grant ATA2010-21322-C03-02 from the Spanish Ministry of Economy and Competitiveness (MINECO). C.J.W. acknowledges support through the Marie Curie Career Integration Grant 303912. V.W. acknowledges support from the European Research Council Starting Grant (SEDMorph P.I. V. Wild) and European Career Re-integration Grant (Phiz-Ev P.I.V. Wild). Y.A. acknowledges financial support from the Ramon y Cajal programme (RyC-2011-09461) and project AYA2013-47742-C4-3-P, both managed by the Ministerio de Economia y Competitividad, as well as the "Study of Emission-Line Galaxies with Integral-Field Spectroscopy" (SELGIFS) programme, funded by the EU (FP7-PEOPLE-2013-IRSES-612701) within the Marie-Sklodowska-Curie Actions scheme. We thank the referee David Wilman for very useful comments that improved the presentation of the paper.This paper describes the Second Public Data Release (DR2) of the Calar Alto Legacy Integral Field Area (CALIFA) survey. The data for 200 objects
are made public, including the 100 galaxies of the First Public Data Release (DR1). Data were obtained with the integral-field spectrograph
PMAS/PPak mounted on the 3.5 m telescope at the Calar Alto observatory. Two different spectral setups are available for each galaxy, (i) a lowresolution V500 setup covering the wavelength range 3745â7500 Ă
with a spectral resolution of 6.0 Ă
(FWHM); and (ii) a medium-resolution
V1200 setup covering the wavelength range 3650â4840 Ă
with a spectral resolution of 2.3 Ă
(FWHM). The sample covers a redshift range between
0.005 and 0.03, with a wide range of properties in the colorâmagnitude diagram, stellar mass, ionization conditions, and morphological types. All
the cubes in the data release were reduced with the latest pipeline, which includes improved spectrophotometric calibration, spatial registration,
and spatial resolution. The spectrophotometric calibration is better than 6% and the median spatial resolution is 200 : 4. In total, the second data
release contains over 1.5 million spectra.Instituto de Salud Carlos III
Spanish Government
AYA2010-15081
AYA2010-15196European Union (EU)
PCIG12-GA-2012-326466Spanish Ministry of Economy and Competitiveness (MINECO)
AYA2010-21322-C03-02
AIB-2010-DE-00227FP7 Marie Curie Actions of the European Commission, via the Initial Training Network DAGAL under REA
289313Ministry of Economy, Development, and Tourism's Millennium Science Initiative
IC12009Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT)
CONICYT FONDECYT
3140566Fundacao para a Ciencia e a Tecnologia (FCT) from FCT (Portugal)
SFRH/BPD/66958/2009Spanish programme of International Campus of Excellence Moncloa (CEI)European Research Council (ERC)Junta de Andalucia
TIC 114
PO08-TIC-3531French National Research Agency (ANR)
ANR-12-BS05-0016-02Spanish Government
AYA2010-21887-C04-02FCT Investigador Contract - FCT/MCTES (Portugal)European Commission Joint Research Centre
European Social Fund (ESF)FCT - FCT-MEC (PIDDAC)
FCOMP-01-0124-FEDER-029170
FCT PTDC/FIS-AST/3214/2012European Union (EU)Spanish Ministerio de Educacion, Cultura y Deporte by FPURamon y Cajal program from the Spanish Ministry of Economy and Competitiveness (MINECO)
ATA2010-21322-C03-02European Union (EU)
303912European Career Re-integration GrantSpanish Government
RyC-2011-09461
AYA2013-47742-C4-3-PEuropean Union (EU)
FP7-PEOPLE-2013-IRSES-612701PTDC/FIS-AST/3214/2012Science & Technology Facilities Council (STFC)
ST/K000985/
GENOTOXICITY OF SHALLOW WATERS NEAR THE BRAZILIAN ANTARCTIC STATION "COMANDANTE FERRAZ" (EACF), ADMIRALTY BAY, KING GEORGE ISLAND, ANTARCTICA
Series of biomonitoring surveys were undertaken weekly in February 2012 to investigate the genotoxicity of the shallow waters around the Brazilian Antarctic Station "Comandante Ferraz" (EACF). The comet assay was applied to assess the damage to the DNA of hemocytes of the crustacean amphipods Gondogeneia antarctica collected from shallow waters near the Fuel Tanks (FT) and Sewage Treatment Outflow (STO) of the research station, and compare it to the DNA damage of animals from Punta Plaza (PPL) and Yellow Point (YP), natural sites far from the EACF defined as experimental controls. The damage to the DNA of hemocytes of G. antarctica was not significantly different between sites in the biomonitoring surveys I and II. In survey III, the damage to the DNA of animals captured in shallow waters near the Fuel Tanks (FT) and Sewage Treatment Outflow (STO) was significantly higher than that of the control site of Punta Plaza (PPL). In biomonitoring survey IV, a significant difference was detected only between the FT and PPL sites. Results demonstrated that the shallow waters in front of the station may be genotoxic and that the comet assay and hemocytes of G. antarctica are useful tools for assessing genotoxicity in biomonitoring studies of Antarctic marine coastal habitats
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