The young stellar population of NGC 4214 as observed with HST. I. Data and methods

We present the data and methods that we have used to perform a detailed UV-optical study of the nearby dwarf starburst galaxy NGC 4214 using multifilter HST/WFPC2+STIS photometry. We explain the process followed to obtain high-quality photometry and astrometry of the stellar and cluster populations of this galaxy. We describe the procedure used to transform magnitudes and colors into physical parameters using spectral energy distributions. The data show the existence of both young and old stellar populations that can be resolved at the distance of NGC 4214 (2.94 Mpc) and we perform a general description of those populations.Comment: 33 pages, 9 figures, and 8 table

On the presence of Alsodes coppingeri (Anura, Alsodidae) in Argentina, with comments on other southern Alsodes

The occurrence of Alsodes coppingeri is confirmed in Argentina for the first time, from Santa Cruz Province, close to the Lago del Desierto. Specimens of this species were identified according to external morphology and DNA sequences. These new records in Argentina are at the same latitude than the type locality (Puerto Río Frío, Chile) about 100 km eastwards in a straight-line, but at the opposite side of the Andes mountain range and the Southern Continental Ice Fields. Five localities from Chile (Caleta Tortel, Canal Michel, Laguna Caiquenes, Puerto Yungay, and Villa O’Higgins) are around 100 km north from our records, in a lower region of the Andes located between the Northern and Southern Continental Ice Fields. This region with discontinuous permanent ice sheet-cover may have acted as a corridor for amphibian species that are currently distributed on both sides of the Andes range.Fil: Barrasso, Diego Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Diversidad y Evolución Austral; ArgentinaFil: Úbeda, Carmen A.. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Departamento de Biología; ArgentinaFil: Cotichelli, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Diversidad y Evolución Austral; ArgentinaFil: Basso, Nestor Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Diversidad y Evolución Austral; Argentin

Identidad Visual Regional para el Corredor Turístico de la Reserva Natural Tisey-Estanzuela, Estelí-Nicaragua

El corredor turístico de la reserva natural Tisey-Estanzuela, ubicada en el departamento de Estelí, es una insignia de las riquezas naturales y culturales del norte de Nicaragua. Para la presente investigación, se identificaron aspectos que fundamentan la necesidad de la creación de una identidad visual efectiva, específicamente desarrollada para entornos turísticos y comunitarios, respondiendo al objetivo general de formular una propuesta de una identidad visual regional para el corredor turístico de la reserva natural Tisey-Estanzuela del departamento de Estelí, Nicaragua. El enfoque de la investigación es mixto, paradigma interpretativo y de corte transversal. El trabajo de campo consistió en la aplicación de una entrevista estructurada, como herramienta de recopilación de datos, implementada ante el Instituto Nicaragüense de Turismo (INTUR), así como una encuesta realizada ante turistas de la reserva natural. Una vez obtenidos los resultados de la investigación, se demostró la necesidad de la creación de una Identidad visual, representante de la cultura regional del corredor turístico Tisey Estanzuela, que logre promocionar las distintas actividades económicas ubicadas en esta región, la cual beneficiará al crecimiento económico comunitario. Es por ello que el desarrollo del estudio concluyó con la propuesta de un manual de marca, que pudiese ser utilizado por los diferentes negocios de la localidad, así como el estado nicaragüense para su continua promoción del turismo rural comunitario

Identidad Visual Regional para el Corredor Turístico de la Reserva Natural Tisey-Estanzuela, Estelí – Nicaragua

El corredor turístico de la reserva natural Tisey-Estanzuela, ubicada en el departamento de Estelí, es una insignia de las riquezas naturales y culturales del norte de Nicaragua. Para la presente investigación, se identificaron aspectos que fundamentan la necesidad de la creación de una identidad visual efectiva, específicamente desarrollada para entornos turísticos y comunitarios, respondiendo al objetivo general de formular una propuesta de una identidad visual regional para el corredor turístico de la reserva natural Tisey-Estanzuela del departamento de Estelí, Nicaragua. El enfoque de la investigación es mixto, paradigma interpretativo y de corte transversal. El trabajo de campo consistió en la aplicación de una entrevista estructurada, como herramienta de recopilación de datos, implementada ante el Instituto Nicaragüense de Turismo (INTUR), así como una encuesta realizada ante turistas de la reserva natural. Una vez obtenidos los resultados de la investigación, se demostró la necesidad de la creación de una Identidad visual, representante de la cultura regional del corredor turístico Tisey-Estanzuela, que logre promocionar las distintas actividades económicas ubicadas en esta región, la cual beneficiará al crecimiento económico comunitario. Es por ello que el desarrollo del estudio concluyó con la propuesta de un manual de marca, que pudiese ser utilizado por los diferentes negocios de la localidad, así como el estado nicaragüense para su continua promoción del turismo rural comunitario

The young stellar population of NGC 4214 as observed with HST. II. Results

We present the results of a detailed UV-optical study of the nearby dwarf starburst galaxy NGC 4214 using multifilter HST/WFPC2+STIS photometry. The stellar extinction is found to be quite patchy, with some areas having values of E(4405-5495)< 0.1 mag and others, associated with star forming regions, much more heavily obscured, a result which is consistent with previous studies of the nebular extinction. We determined the ratio of blue-to-red supergiants and found it to be consistent with theoretical models for the metallicity of the SMC. The stellar IMF of the field in the range 20-100 solar masses is found to be steeper than Salpeter. A number of massive clusters and associations with ages between a few and 200 million years are detected and their properties are discussed.Comment: 49 pages, 12 figures, 6 table

Wolf-Rayet Stars in M33 II: Optical Spectroscopy of emission-line stars in Giant Hii Regions

We present optical spectra of 14 emission-line stars in M33s giant HII regions NGC 592, NGC 595 and NGC 604: five of them are known WR stars, for which we present a better quality spectrogram, eight were WR candidates based on narrow-band imagery and one is a serendipitous discovery. Spectroscopy confirms the power of interference filter imagery to detect emission-line stars down to an equivalent width of about 5 A in crowded fields. We have also used archival HST/WFPC2 images to correctly identify emission-line stars in NGC 592 and NGC 588. emission-line stars in NGC 592 and NGC 588.Comment: 9 pages, 14 figures, revised version submitted to MNRA

Spectroscopic Time-series Performance of JWST/NIRSpec from Commissioning Observations

We report on JWST commissioning observations of the transiting exoplanet HAT-P-14 b, obtained using the Bright Object Time Series (BOTS) mode of the NIRSpec instrument with the G395H/F290LP grating/filter combination ($3-5\mu$m). While the data were used primarily to verify that the NIRSpec BOTS mode is working as expected, and to enable it for general scientific use, they yield a precise transmission spectrum which we find is featureless down to the precision level of the instrument, consistent with expectations given HAT-P-14~b's small scale-height and hence expected atmospheric features. The exquisite quality and stability of the \emph{JWST/NIRSpec} transit spectrum -- almost devoid of any systematic effects -- allowed us to obtain median uncertainties of 50-60 ppm in this wavelength range at a resolution of $R=100$ in a single exposure, which is in excellent agreement with pre-flight expectations and close to the (or at the) photon-noise limit for a $J = 9.094$, F-type star like HAT-P-14. These observations showcase the ability of NIRSpec/BOTS to perform cutting-edge transiting exoplanet atmospheric science, setting the stage for observations and discoveries to be made in Cycle 1 and beyond.Comment: 16 pages, 14 figures; part of the PASP Focus Issue "JWST Time-Series Observations: Commissioning Performance". Paper after the first round of referee comments; inputs welcom

PHANGS-HST Catalogs for ∼100,000 Star Clusters and Compact Associations in 38 Galaxies. I. Observed Properties

We present the largest catalog to date of star clusters and compact associations in nearby galaxies. We have performed a V-band-selected census of clusters across the 38 spiral galaxies of the PHANGS–Hubble Space Telescope (HST) Treasury Survey, and measured integrated, aperture-corrected near-ultraviolet-U-B-V-I photometry. This work has resulted in uniform catalogs that contain ∼20,000 clusters and compact associations, which have passed human inspection and morphological classification, and a larger sample of ∼100,000 classified by neural network models. Here, we report on the observed properties of these samples, and demonstrate that tremendous insight can be gained from just the observed properties of clusters, even in the absence of their transformation into physical quantities. In particular, we show the utility of the UBVI color–color diagram, and the three principal features revealed by the PHANGS-HST cluster sample: the young cluster locus, the middle-age plume, and the old globular cluster clump. We present an atlas of maps of the 2D spatial distribution of clusters and compact associations in the context of the molecular clouds from PHANGS–Atacama Large Millimeter/submillimeter Array. We explore new ways of understanding this large data set in a multiscale context by bringing together once-separate techniques for the characterization of clusters (color–color diagrams and spatial distributions) and their parent galaxies (galaxy morphology and location relative to the galaxy main sequence). A companion paper presents the physical properties: ages, masses, and dust reddenings derived using improved spectral energy distribution fitting techniques

Temas Socio-Jurídicos. Volumen 26 No. 54 Junio de 2008

La revista Temas Socio-jurídicos llega a su edición número 54, en el vigésimo sexto año de publicación continuada con periodicidad semestral; ella es el resultado de la producción intelectual de la comunidad académica Universidad Autónoma de Bucaramanga.The magazine Temas Socio-jurídicos reaches its 54th edition, in its twenty-sixth year of continuous publication on a semi-annual basis; it is the result of the intellectual production of the academic community of the Autonomous University of Bucaramanga

Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe