Guía para la publicación de registros biológicos y fichas de taxones de especies exóticas e invasoras. Volumen 2: Herramienta para la documentación de información sobre especies exóticas e invasoras.

Esta guía tiene como objetivo proveer una herramienta orientadora para la publicación de registros biológicos y de información bioecológica, usos y potencial invasor, como la base para los procesos de evaluación de riesgo de invasión de especies de fauna, flora y recursos hidrobiológicos del país. Se busca tanto la estandarización de los conceptos, terminología, herramientas y metodologías para el manejo de datos sobre especies exóticas y/o invasoras, como el fortalecimiento de una base técnica en la toma de decisiones en esta materia, principalmente sobre aspectos de manejo, control y su posible erradicación. Actualmente los esfuerzos se concentran en la promoción del conocimiento sobre el comportamiento e impactos de estas especies; el cual, a medida que avanza, fortalecerá los sistemas de detección temprana e impulsará la toma de decisiones y la conciencia pública sobre el tema.BogotáCiencias de la Biodiversida

Guía para la publicación de registros biológicos y fichas de taxones de interés para la conservación. Volumen 1: Información para el análisis de riesgo de extinción de especies

Esta guía tiene como objetivo orientar de manera consistente y bajo criterios de calidad, el proceso de estructuración y documentación de información bioecológica y geográfica de las especies de fauna, flora y recursos hidrobiológicos de Colombia; tal información será el insumo principal para realizar los análisis de riesgo de extinción de especies, buscando el fortalecimiento de una base técnica y orientadora para la toma de decisiones en esta materia. En Colombia se decidió adoptar y retroalimentar con los requisitos de la UICN, los estándares Darwin Core (DwC) y Plinian Core (PliC), los cuales fueron diseñados para facilitar y estandarizar la forma en que son publicados y compartidos los datos de biodiversidad, asociados particularmente a la información geográfica y bioecológica de las especies.BogotáCiencias de la Biodiversida

The unusual NIV]-emitter galaxy GDS J033218.92-275302.7: star formation or AGN-driven winds from a massive galaxy at z=5.56

Aims: We investigate the nature of the source GDS J033218.92-275302.7at redshift ~ 5.56. Methods: The SED of the source is well sampled by 16 bands photometry, from UV-optical, near infrared and mid-infrared (MID-IR).The detection of signal in the MID-IR Spitzer/IRAC bands 5.8, 8.0 um -- where the nebular emission contribution is less effective -- suggests the presence of a Balmer break, signature of an underlying stellar population formed at earlier epochs. The optical spectrum shows a clear Lya emission line together with semi-forbidden NIV] 1483.3-1486.5 also in emission. Results: From the SED fitting and the Lya modelling it turns out that the source seems to have an evolved component with stellar mass of ~5 x10^(10) Msolar and age ~ 0.4 Gyrs, and a young component with an age of ~ 0.01 Gyrs and SFR in the range of 30-200 Msolar yr^(-1). The limits on the effective radius derived from the ACS/z850 and VLT/Ks bands indicate that this galaxy is denser than the local ones with similar mass. A relatively high nebular gas column density is favored from the Lya line modelling (NHI>=10^(21) cm^(-2)). A vigorous outflow (~ 450 km/s) has been measured from the optical spectrum,consistent with the Lya modelling. From ACS observations it turns out that the region emitting Lya photons is spatially compact and of the same order of the effective radius estimated at the ~1400A rest-frame wavelength, whose emission is dominated by the stellar continuum and/or AGN. The gas is blown out from the central region,but given the mass of the galaxy it is uncertain whether it will pollute the IGM to large distances. We argue that a burst of star formation in a dense gas environment is active (possibly containing hot and massive stars and/or a low luminosity AGN), superimposed to an already formed fraction of stellar mass (abridged).Comment: 13 pages, 9 figures (published on A&A). Here replaced with a typo fixed in the footnote of Sect. 4.2 and with four updated references. Results unchange

The positive transcriptional elongation factor (P-TEFb) is required for neural crest specification

Regulation of gene expression at the level of transcriptional elongation has been shown to be important in stem cells and tumour cells, but its role in the whole animal is only now being fully explored. Neural crest cells (NCCs) are a multipotent population of cells that migrate during early development from the dorsal neural tube throughout the embryo where they differentiate into a variety of cell types including pigment cells, cranio-facial skeleton and sensory neurons. Specification of NCCs is both spatially and temporally regulated during embryonic development. Here we show that components of the transcriptional elongation regulatory machinery, CDK9 and CYCLINT1 of the P-TEFb complex, are required to regulate neural crest specification. In particular, we show that expression of the proto-oncogene c-Myc and c-Myc responsive genes are affected. Our data suggest that P-TEFb is crucial to drive expression of c-Myc, which acts as a ‘gate-keeper’ for the correct temporal and spatial development of the neural crest

Euclid preparation: XVI. Exploring the ultra-low surface brightness Universe with Euclid /VIS

Context. While Euclid is an ESA mission specifically designed to investigate the nature of dark energy and dark matter, the planned unprecedented combination of survey area (∼15â 000 deg2), spatial resolution, low sky-background, and depth also make Euclid an excellent space observatory for the study of the low surface brightness Universe. Scientific exploitation of the extended low surface brightness structures requires dedicated calibration procedures that are yet to be tested. Aims. We investigate the capabilities of Euclid to detect extended low surface brightness structure by identifying and quantifying sky-background sources and stray-light contamination. We test the feasibility of generating sky flat-fields to reduce large-scale residual gradients in order to reveal the extended emission of galaxies observed in the Euclid survey. Methods. We simulated a realistic set of Euclid/VIS observations, taking into account both instrumental and astronomical sources of contamination, including cosmic rays, stray-light, zodiacal light, interstellar medium, and the cosmic infrared background, while simulating the effects of background sources in the field of view. Results. We demonstrate that a combination of calibration lamps, sky flats, and self-calibration would enable recovery of emission at a limiting surface brightness magnitude of μlim = 29.5-0.27+0.08 mag arcsec-2 (3σ, 10â ×â 10 arcsec2) in the Wide Survey, and it would reach regions deeper by 2 mag in the Deep Surveys. Conclusions.Euclid/VIS has the potential to be an excellent low surface brightness observatory. Covering the gap between pixel-To-pixel calibration lamp flats and self-calibration observations for large scales, the application of sky flat-fielding will enhance the sensitivity of the VIS detector at scales larger than 1″, up to the size of the field of view, enabling Euclid to detect extended surface brightness structures below μlimâ =â 31 mag arcsec-2 and beyond

Euclid preparation: XVI. Exploring the ultra-low surface brightness Universe with Euclid/VIS

Context While Euclid is an ESA mission specifically designed to investigate the nature of dark energy and dark matter, the planned unprecedented combination of survey area (∼15 000 deg2), spatial resolution, low sky-background, and depth also make Euclid an excellent space observatory for the study of the low surface brightness Universe. Scientific exploitation of the extended low surface brightness structures requires dedicated calibration procedures that are yet to be tested. Aims We investigate the capabilities of Euclid to detect extended low surface brightness structure by identifying and quantifying sky-background sources and stray-light contamination. We test the feasibility of generating sky flat-fields to reduce large-scale residual gradients in order to reveal the extended emission of galaxies observed in the Euclid survey. Methods We simulated a realistic set of Euclid/VIS observations, taking into account both instrumental and astronomical sources of contamination, including cosmic rays, stray-light, zodiacal light, interstellar medium, and the cosmic infrared background, while simulating the effects of background sources in the field of view. Results We demonstrate that a combination of calibration lamps, sky flats, and self-calibration would enable recovery of emission at a limiting surface brightness magnitude of μlim = 29.5-0.2+0.08 mag arcsec-2 (3σ, 10 × 10 arcsec2) in the Wide Survey, and it would reach regions deeper by 2 mag in the Deep Surveys. Conclusions Euclid/VIS has the potential to be an excellent low surface brightness observatory. Covering the gap between pixel-To-pixel calibration lamp flats and self-calibration observations for large scales, the application of sky flat-fielding will enhance the sensitivity of the VIS detector at scales larger than 1″, up to the size of the field of view, enabling Euclid to detect extended surface brightness structures below μlim = 31 mag arcsec-2 and beyond

Procedimiento para obtención de placas poliméricas reforzadas con fibra natural

En esta investigación se presenta una metodología para la elaboración de láminas compuestas de polietileno de baja densidad (LDPE) y fibra natural. El proceso de mezclado se realizó con un equipo de cámara interna tipo banbury a nivel de laboratorio. Posteriormente fue sometido al proceso de moldeo por compresión, para ello se utilizó una prensa hidráulica con sistema de calentamiento. Inicialmente las láminas presentaron varios problemas de calidad entre ellos, presencia de burbujas, irregularidad superficial y geométrica. Mediante la aplicación de acciones correctivas tales como la aplicación de vacío en la etapa de mezclado, el laminado del material antes de ser puesto en el molde y la incorporación de fibra de tamaño de partícula entre 300-1000 µm se obtuvieron láinas de excelente acabado

Descubrimiento del primer yacimiento cuaternario (Riss-Würm) de vertebrados con restos humanos en la provincia de Madrid (Pinilla del Valle)

Se da a conocer un nuevo yacimiento de vertebrados del Pleistoceno situado en la localidad de Pinilla del Valle (Madrid), constituido por sedimentos cuaternarios que rellenan un antiguo abrigo calcáreo desplomado. Las excavaciones efectuadas hasta ahora han proporcionado una rica asociación faunística en la que se han identificado hasta la actualidad 14 órdenes de Vertebrados representados por 30 familias, con una mayor abundancia de Mamíferos. Algunos elementos faunísticos de este último grupo permiten datar provisionalmente el yacimiento como perteneciente al interglacial Riss-Würm (Eemiense) o a algún interestadial del Riss. Es de resaltar la aparición de utensilios en hueso toscamente trabajados y otros quemados, indicando una evidente acción antropogénica. Esta hipótesis se ha confirmado con la aparición de un molar humano (M derecho) que abre una esperanzadora espectativa de encontrar nuevos restos humanos