Genetica del trigo. Los cereales. Biología Molecular e Ingeniería Genética

El presente artículo revisa sucintamente un conjunto de investigaciones sobre los cereales, realizadas en el Departamento de Bioquímica de la E.T.S. de Ingenieros Agrónomos de la Universidad Politécnica de Madrid. En dichas investigaciones se han utilizado técnicas bioquímicas, citogenéticas y de ingeniería genética para el conocimiento básico y la manipulación práctica del conjunto de especies cultivadas denominadas cereales. Los estudios realizados han abarcado los siguientes aspectos principales: purificación y caracterización de proteinas, c caracterizacion y localización cromosómica de genes estructurales y reguladores involucrados en el control genético de la composición bioquímica del tejido, clonaje de genes de plantas en bacterias, y transferencia génica entre especies vegetales. Las aplicaciones prácticas derivadas hasta ahora incluyen desde métodos para la identificación de especies, variedades y materias primas, a la transferencia de genes de interés agronómico desde especies silvestres a cultivadas. A medio plazo, los avances realizados en la manipulación in vitro de genes vegetales serán de utilidad práctica en la aplicación de la ingeniería genética a la mejora vegeta

Probing the massive star forming environment - a multiwavelength investigation of the filamentary IRDC G333.73+0.37

We present a multiwavelength study of the filamentary infrared dark cloud (IRDC) G333.73+0.37. The region contains two distinct mid-infrared sources S1 and S2 connected by dark lanes of gas and dust. Cold dust emission from the IRDC is detected at seven wavelength bands and we have identified 10 high density clumps in the region. The physical properties of the clumps such as temperature: 14.3-22.3 K and mass: 87-1530 M_sun are determined by fitting a modified blackbody to the spectral energy distribution of each clump between 160 micron and 1.2 mm. The total mass of the IRDC is estimated to be $~4700 M_sun. The molecular line emission towards S1 reveals signatures of protostellar activity. Low frequency radio emission at 1300 and 610 MHz is detected towards S1 (shell-like) and S2 (compact morphology), confirming the presence of newly formed massive stars in the IRDC. Photometric analysis of near and mid-infrared point sources unveil the young stellar object population associated with the cloud. Fragmentation analysis indicates that the filament is supercritical. We observe a velocity gradient along the filament, that is likely to be associated with accretion flows within the filament rather than rotation. Based on various age estimates obtained for objects in different evolutionary stages, we attempt to set a limit to the current age of this cloud.Comment: 26 pages, 20 figures, accepted by Ap

Evolution and excitation conditions of outflows in high-mass star-forming regions

Theoretical models suggest that massive stars form via disk-mediated accretion, with bipolar outflows playing a fundamental role. A recent study toward massive molecular outflows has revealed a decrease of the SiO line intensity as the object evolves. The present study aims at characterizing the variation of the molecular outflow properties with time, and at studying the SiO excitation conditions in outflows associated with massive YSOs. We used the IRAM30m telescope to map 14 massive star-forming regions in the SiO(2-1), SiO(5-4) and HCO+(1-0) outflow lines, and in several dense gas and hot core tracers. Hi-GAL data was used to improve the spectral energy distributions and the L/M ratio, which is believed to be a good indicator of the evolutionary stage of the YSO. We detect SiO and HCO+ outflow emission in all the sources, and bipolar structures in six of them. The outflow parameters are similar to those found toward other massive YSOs. We find an increase of the HCO+ outflow energetics as the object evolve, and a decrease of the SiO abundance with time, from 10^(-8) to 10^(-9). The SiO(5-4) to (2-1) line ratio is found to be low at the ambient gas velocity, and increases as we move to high velocities, indicating that the excitation conditions of the SiO change with the velocity of the gas (with larger densities and/or temperatures for the high-velocity gas component). The properties of the SiO and HCO+ outflow emission suggest a scenario in which SiO is largely enhanced in the first evolutionary stages, probably due to strong shocks produced by the protostellar jet. As the object evolves, the power of the jet would decrease and so does the SiO abundance. During this process, however, the material surrounding the protostar would have been been swept up by the jet, and the outflow activity, traced by entrained molecular material (HCO+), would increase with time.Comment: 31 pages, 10 figures and 5 tables (plus 2 figures and 3 tables in the appendix). Accepted for publication in A&A. [Abstract modified to fit the arXiv requirements.

Projecte d'urbanització del sector UP9 de Parets del Vallès

El present projecte d’urbanització definirà les actuacions a realitzar en el sector UP9 en el terme municipal de Parets del Vallès. El municipi de Parets del Vallès està situat al sud-oest del Vallès Oriental. Té una extensió de 11,5 km2, amb una població de 18.492 habitants (INE 2012). Es troba a 7 km de Granollers i a 23 km de Barcelona. La riera de Tenes travessa el municipi de nord a sud, poc abans de desguassar al riu Besòs. La xarxa de comunicacions està formades per les vies principals que circulen pel seu terme: les autopistes A-7 de Barcelona a la Jonquera i la C-33 de Mollet al Papiol, la carretera C-17 de Barcelona a Vic, la carretera local que du a Bigues i la comarcal de Sabadell a Granollers. Hi ha, a més, estació del ferrocarril de Barcelona a Sant Joan de les Abadesses

Efectos de simplificación de textos en la comprensión lectora de las personas con discapacidad intelectual

La presente tesis se presenta en la modalidad de “compendio de publicaciones” y está dedicada al análisis de las variables psicolingüísticas que afectan a la comprensión en la simplificación de textos dirigidos a lectores jóvenes de entre 16 y 23 años con DI. En este punto se hace necesaria la definición breve de dos conceptos que serán abordados con mayor profundidad a lo largo del compendio: 1) “simplificación de textos”, que entendemos como el proceso de reducir la complejidad lingüística de un texto mientras se mantiene la información y el significado original (Siddharthan, 2014), y 2) Discapacidad Intelectual, entendida como un trastornos del neuro-desarrollo caracterizado por déficits en funcionamiento intelectual y adaptativo que se presenta antes de los 18 años (American Psychiatric Association, 2013). “Simplificación de textos”, “adaptación de textos”, diseño de textos de “Lectura Fácil” o “controlados lingüísticamente” son todos términos similares empleados para designar un conjunto de técnicas que con frecuencia se combinan con la instrucción directa para mejorar la comprensión lectora de los lectores con dificultades (Arfé, Oakhill, y Pianta, 2014; Lundberg y Reichenberg, 2013; Morgan y Moni, 2008; Quigley y King, 1981-1984). Como adelantábamos en el párrafo anterior, este sería el caso de los estudiantes con DI, un colectivo que usualmente presenta habilidades lectoras por debajo de la esperada para su edad (Channell, Loveall, y Conners, 2013; van den Bos, Nakken, Nicolay, y van Houten, 2007). Teniendo estos conceptos centrales definidos, pasamos a explicar la estructura de la tesis. Dedicado pues a este tema, el compendio consta de 5 Estudios distribuidos en 3 artículos: cada artículo se compone de 2 Estudios, a excepción del primero, que contiene sólo uno

Physical properties of high-mass clumps in different stages of evolution

(Abridged) Aims. To investigate the first stages of the process of high-mass star formation, we selected a sample of massive clumps previously observed with the SEST at 1.2 mm and with the ATNF ATCA at 1.3 cm. We want to characterize the physical conditions in such sources, and test whether their properties depend on the evolutionary stage of the clump. Methods. With ATCA we observed the selected sources in the NH3(1,1) and (2,2) transitions and in the 22 GHz H2O maser line. Ammonia lines are a good temperature probe that allow us to accurately determine the mass and the column-, volume-, and surface densities of the clumps. We also collected all data available to construct the spectral energy distribution of the individual clumps and to determine if star formation is already occurring, through observations of its most common signposts, thus putting constraints on the evolutionary stage of the source. We fitted the spectral energy distribution between 1.2 mm and 70 microns with a modified black body to derive the dust temperature and independently determine the mass. Results. The clumps are cold (T~10-30 K), massive (M~10^2-10^3 Mo), and dense (n(H2)>~10^5 cm^-3) and they have high column densities (N(H2)~10^23 cm^-2). All clumps appear to be potentially able to form high-mass stars. The most massive clumps appear to be gravitationally unstable, if the only sources of support against collapse are turbulence and thermal pressure, which possibly indicates that the magnetic field is important in stabilizing them. Conclusions. After investigating how the average properties depend on the evolutionary phase of the source, we find that the temperature and central density progressively increase with time. Sources likely hosting a ZAMS star show a steeper radial dependence of the volume density and tend to be more compact than starless clumps.Comment: Published in A&A, Vol. 556, A1

Thermal Jeans fragmentation within 1000 AU in OMC-1S

We present subarcsecond 1.3 mm continuum ALMA observations towards the Orion Molecular Cloud 1 South (OMC-1S) region, down to a spatial resolution of 74 AU, which reveal a total of 31 continuum sources. We also present subarcsecond 7 mm continuum VLA observations of the same region, which allow to further study fragmentation down to a spatial resolution of 40 AU. By applying a Mean Surface Density of Companions method we find a characteristic spatial scale at ~560 AU, and we use this spatial scale to define the boundary of 19 `cores' in OMC-1S as groupings of millimeter sources. We find an additional characteristic spatial scale at ~2900 AU, which is the typical scale of the filaments in OMC-1S, suggesting a two-level fragmentation process. We measured the fragmentation level within each core and find a higher fragmentation towards the southern filament. In addition, the cores of the southern filament are also the densest (within 1100 AU) cores in OMC-1S. This is fully consistent with previous studies of fragmentation at spatial scales one order of magnitude larger, and suggests that fragmentation down to 40 AU seems to be governed by thermal Jeans processes in OMC-1S.Comment: Accepted to Ap

Water in the Disks Around Massive Young Stars

N/