Discurso educativo del área de inglés configurado en el centro virtual de noticias de educación (CV NE)

EI presente ejercicio formativo se enmarca dentro de una investigación de carácter cualitativo que pretende identificar los rasgos características del Discurso Educativo (DE) construido en las noticias virtuales del arca de inglés del Centro Virtual de Noticias de la Educación (CVNE). Esta es una plataforma virtual que funciona como herramienta de información, divulgación y comunicación de noticias educativas disponible para la comunidad inmersa en el ámbito académico, creada en el 2006 por el Ministerio de Educación Nacional. Así, en el marco teórico se desarrollan tres grandes categorías: (1) Discurso, Análisis Crítico del Discurso (ACD), Educación, ACD y Educación, (2) Discurso Educativo, y, (3) Los medios de comunicación emergentes y la noticia, la noticia como discurso y la noticia digital. Entonces, para develar el Discurso Educativo, se recurre al Análisis Crítico del Discurso de 50 noticias obtenidas de la plataforma informativa que se publicaron entre los años 2011 y 2015. El DE aquí, se logra identificar gracias al análisis de: a) tópicos como la noción de bilingüismo o la percepción de docentes extranjeros, y, b) la representación de los actores y las acciones que se les atribuyen dentro del discurso noticioso del CVNE. Gracias a estas categorías y al proceso de análisis, se logra vislumbrar la configuración de un DE que considera la preparación de los profesores de lengua colombianos como insuficiente: la aprobación de las prácticas locales por parte de los extranjeros necesaria, los actores institucionales (MEN, gobierno) protagonistas de las dinámicas educativas y a los docentes como I agentes pasivos que son ante todo receptores de los beneficios otorgados por el gobierno.The present formative exercise is allocated under the framework of a qualitative rescan h. which I I has as a goal the identification ol charac teristics and features of the 1 Educational Discourse fl D) I I configured in the virtual news around the I nglish urea on the platform Centro Virtual de Noticias de Educación (CVNE). This wchsite, created in 2016 by the Education Ministry, works as a tool for information, divulgation and educative news communication available to all the 1 I academic community. Thus, in order to reveal the Educational Discourse, we appeal to the Critical Discourse Analysis (CDA) of 50 news selected from the platform published in the years between 2011 -2015. The ED is identified thanks to a) Topics analysis where notions around such items as bilingualism or foreign teachers are seen under the scope of the CDA, b) Actors representations and actions assigned in the news discourse promoted by the CVNE. Thanks to these main categories and to the analysis process this work manages to achieve the configuration of an ED, which considers the formation of Colombian language teachers, insufficient and the approval of local pedagogical practices by foreign teachers, necessary, furthermore, the I D. shown in this research, has the institutional actors in the spotlight of its news and local teachers and students as passive actors horn receive all the benefits given by the government.Licenciado (a) en Lenguas ModernasPregrad

The Intracluster Plasma: a Universal Pressure Profile?

The pressure profiles of the Intracluster Plasma in galaxy clusters show a wide variance when observed in X rays at low redshifts z<0.2. We find the profiles to follow two main patterns, featuring either a steep or a shallow shape throughout both core and outskirts. We trace these shapes back to a physical dichotomy of clusters into two classes, marked by either low entropy (LE) or high entropy (HE) throughout. From X-ray observations and Sunyaev-Zel'dovich stacked data at higher 0.2<z<0.4, we elicit evidence of an increasing abundance of HEs relative to LEs. We propose this to constitute a systematic trend toward high z; specifically, we predict the pressure profiles to converge into a truly universal HE-like template for z>0.5. We submit our physical templates and converging trend for further observational tests, in view of the current and upcoming measurements of individual, stacked, and integrated Sunyaev-Zel'dovich signals.Comment: 5 pages, 2 figures. Typos-corrected. Accepted by ApJ

The pseudo-evolution of halo mass

A dark matter halo is commonly defined as a spherical overdensity of matter with respect to a reference density, such as the critical density or the mean matter density of the Universe. Such definitions can lead to a spurious pseudo-evolution of halo mass simply due to redshift evolution of the reference density, even if its physical density profile remains constant over time. We estimate the amount of such pseudo-evolution of mass between z=1 to 0 for halos identified in a large N-body simulation, and show that it accounts for almost the entire mass evolution of the majority of halos with M200 of about 1E12 solar masses and can be a significant fraction of the apparent mass growth even for cluster-sized halos. We estimate the magnitude of the pseudo-evolution assuming that halo density profiles remain static in physical coordinates, and show that this simple model predicts the pseudo-evolution of halos identified in numerical simulations to good accuracy, albeit with significant scatter. We discuss the impact of pseudo-evolution on the evolution of the halo mass function and show that the non-evolution of the low-mass end of the halo mass function is the result of a fortuitous cancellation between pseudo-evolution and the absorption of small halos into larger hosts. We also show that the evolution of the low mass end of the concentration-mass relation observed in simulations is almost entirely due to the pseudo-evolution of mass. Finally, we discuss the implications of our results for the interpretation of the evolution of various scaling relations between the observable properties of galaxies and galaxy clusters and their halo masses.Comment: 15 pages, 9 figures. Minor changes. Published Versio

The Uchuu-UniverseMachine dataset: Galaxies in and around Clusters

We present the public data release of the Uchuu-UM galaxy catalogues by applying the UniverseMachine algorithm to assign galaxies to the dark matter halos in the Uchuu $N$-body cosmological simulation. It includes a variety of baryonic properties for all galaxies down to $\sim 5\times10^8 M_{\odot}$ with halos in a mass range of $10^{10}<M_{\rm halo}/M_{\odot}<5\times10^{15}$ up to redshift $z=10$. Uchuu-UM includes more than $10^{4}$ cluster-size halos in a volume of $8(h^{-1} {\rm Gpc})^3$, reproducing observed stellar mass functions across the redshift range of $z=0-7$, galaxy quenched fractions, and clustering statistics at low redshifts. Compared to the previous largest UM catalogue, the Uchuu-UM catalogue includes significantly more massive galaxies hosted by large-mass dark matter halos. Overall, the number density profile of galaxies in dark matter halos follows the dark matter profile, with the profile becoming steeper around the splashback radius and flattening at larger radii. The number density profile of galaxies tends to be steeper for larger stellar masses and depends on the color of galaxies, with red galaxies having steeper slopes at all radii than blue galaxies. The quenched fraction exhibits a strong dependence on the stellar mass and increases toward the inner regions of clusters. The publicly available Uchuu-UM galaxy catalogue presented here can serve to model ongoing and upcoming large galaxy surveys.Comment: 10 pages, 11 figures, accepted by MNRAS, public data available at http://www.skiesanduniverses.org

Halos and galaxies in the standard cosmological model: results from the Bolshoi simulation

We present the first results from the new Bolshoi N-body cosmological LCDM simulation that uses cosmological parameters favored by current observations. The Bolshoi simulation was done in a volume 250Mpc on a side using 8billion particles with mass and force resolution adequate to follow subhalos down to a completeness limit of Vcirc=50km/ s circular velocity. Using excellent statistics of halos and subhalos (10M at every moment and 50M over the whole history) we present accurate approximations for statistics such as the halo mass function, the concentrations for distinct halos and subhalos, abundance of halos as function of their circular velocity, the abundance and the spatial distribution of subhalos. We find that at high redshifts the concentration falls to a minimum of about 3.8 and then rises slightly for higher values of halo mass. We find that while the Sheth-Tormen approximation for the mass function of halos found by spherical overdensity is accurate at low redshifts, it over-predicts the abundance of halos by nearly an order of magnitude by z=10. We find that the number of subhalos scales with the circular velocity of the host halo as Vhost**0.5, and that subhalos have nearly the same radial distribution as dark matter particles at radii 0.3-2 times the host halo virial radius. The subhalo velocity function n(>V) behaves as V**(-3). We give normalization of this relation for different masses and redshifts. Finally, we use an abundance-matching procedure to assign r-band luminosities to dark matter halos as a function of halo Vcirc, and find that the luminosity-velocity relation is in remarkably good agreement with the observed Tully-Fisher relation for galaxies in the range 50-200km/s.Comment: 28 pages, 22 figures, accepted for publication in Ap

The MUSIC of Galaxy Clusters I: Baryon properties and Scaling Relations of the thermal Sunyaev-Zel'dovich Effect

We introduce the Marenostrum-MultiDark SImulations of galaxy Clusters (MUSIC) Dataset, one of the largest sample of hydrodynamically simulated galaxy clusters with more than 500 clusters and 2000 groups. The objects have been selected from two large N-body simulations and have been resimulated at high resolution using SPH together with relevant physical processes (cooling, UV photoionization, star formation and different feedback processes). We focus on the analysis of the baryon content (gas and star) of clusters in the MUSIC dataset both as a function of aperture radius and redshift. The results from our simulations are compared with the most recent observational estimates of the gas fraction in galaxy clusters at different overdensity radii. When the effects of cooling and stellar feedbacks are included, the MUSIC clusters show a good agreement with the most recent observed gas fractions quoted in the literature. A clear dependence of the gas fractions with the total cluster mass is also evident. The impact of the aperture radius choice, when comparing integrated quantities at different redshifts, is tested: the standard definition of radius at a fixed overdensity with respect to critical density is compared with a definition based on the redshift dependent overdensity with respect to background density. We also present a detailed analysis of the scaling relations of the thermal SZ (Sunyaev Zel'dovich) Effect derived from MUSIC clusters. The integrated SZ brightness, Y, is related to the cluster total mass, M, as well as, the M-Y counterpart, more suitable for observational applications. Both laws are consistent with predictions from the self-similar model, showing a very low scatter. The effects of the gas fraction on the Y-M scaling and the presence of a possible redshift dependence on the Y-M scaling relation are also explored.Comment: 22 pages, 25 figures, accepted for pubblication by MNRA

100 Mujeres: Una Iniciativa De Educación Ambiental Con Perspectiva De Género

En la mayoría de países, las mujeres son discriminadas y no son tenidas en cuenta para llevar a cabo procesos y tomar decisiones en cualquier ámbito, incluidos los procesos ambientales, a pesar de ser las principales administradoras de los recursos ambientales desde las actividades domésticas y de otros múltiples roles que ellas juegan en el hogar. Debido a esto, el objetivo del trabajo fue disminuir la presión que ejercen las labores domésticas sobre el río Orotoy, mediante el fortalecimiento del papel de la mujer como eje social para el mejoramiento de la calidad y estilos de vida ambientalmente sanos. El trabajo se desarrolló utilizando diferentes técnicas de la investigación acción participativa como son las entrevistas, los grupos de encuentros o talleres (ambiental, producción, salud y social), y las encuestas. Como resultado se encontró que la mayoría de las asistentes al proyecto no conocían sus derechos como mujer, su importancia en lo que respecta a lo ambiental y su importancia como administradoras de su hogar. Finalmente se logró un empoderamiento de la mujer como líder de su familia y de su comunidad con nuevos conocimientos sobre potabilización, producción de alimentos en el hogar y manejo de residuos sólidos que fomentan relaciones amigables con el medio ambiente.AbstractIn most countries, women are discriminated against and are not taken into account in carrying out processes and decisions in any sphere, including environmental processes, despite of being the main administrators of the environmental resources from the domestic activities among the other multiple roles that they play at home. Due to this, the main objective of this work was to diminish the pressure of domestic labors over the Orotoy Luna Azul ISSN 1909-2474 No. 36, enero - junio 2013 ©Universidad de Caldas revista.luna.azúl. 2013; 36: 26-39 River, through the strengthening of the role of women as a social hub for the improvement of quality and environmentally healthy lifestyles. This work was developed by using different participatory action research techniques such as interviews, group meetings or workshops (environmental, production, health and social), and surveys. As a result it was found that the majority of the project participants did not know their rights as a woman, their importance into the environmental debate and their role as home administrators. Finally it was accomplished a woman empowerment as a leader into their family and community, with a new knowledge about potabilization, food production at home and solid waste management that foster a more friendly relationship with the environment.En la mayoría de países, las mujeres son discriminadas y no son tenidas en cuenta para llevar a cabo procesos y tomar decisiones en cualquier ámbito, incluidos los procesos ambientales, a pesar de ser las principales administradoras de los recursos ambientales desde las actividades domésticas y de otros múltiples roles que ellas juegan en el hogar. Debido a esto, el objetivo del trabajo fue disminuir la presión que ejercen las labores domésticas sobre el río Orotoy, mediante el fortalecimiento del papel de la mujer como eje social para el mejoramiento de la calidad y estilos de vida ambientalmente sanos. El trabajo se desarrolló utilizando diferentes técnicas de la investigación acción participativa como son las entrevistas, los grupos de encuentros o talleres (ambiental, producción, salud y social), y las encuestas. Como resultado se encontró que la mayoría de las asistentes al proyecto no conocían sus derechos como mujer, su importancia en lo que respecta a lo ambiental y su importancia como administradoras de su hogar. Finalmente se logró un empoderamiento de la mujer como líder de su familia y de su comunidad con nuevos conocimientos sobre potabilización, producción de alimentos en el hogar y manejo de residuos sólidos que fomentan relaciones amigables con el medio ambiente.AbstractIn most countries, women are discriminated against and are not taken into account in carrying out processes and decisions in any sphere, including environmental processes, despite of being the main administrators of the environmental resources from the domestic activities among the other multiple roles that they play at home. Due to this, the main objective of this work was to diminish the pressure of domestic labors over the Orotoy Luna Azul ISSN 1909-2474 No. 36, enero - junio 2013 ©Universidad de Caldas revista.luna.azúl. 2013; 36: 26-39 River, through the strengthening of the role of women as a social hub for the improvement of quality and environmentally healthy lifestyles. This work was developed by using different participatory action research techniques such as interviews, group meetings or workshops (environmental, production, health and social), and surveys. As a result it was found that the majority of the project participants did not know their rights as a woman, their importance into the environmental debate and their role as home administrators. Finally it was accomplished a woman empowerment as a leader into their family and community, with a new knowledge about potabilization, food production at home and solid waste management that foster a more friendly relationship with the environment

Satellite number density profiles of primary galaxies in the 2dFGRS

We analyse the projected radial distribution of satellites around bright primary galaxies in the 2dFGRS. We have considered several primary-satellite subsamples to search for dependences of the satellite number density profile, \rho(r_p), on properties of satellites and primaries. We find significant differences of the behaviour of \rho(r_p) depending on primary characteristics. In star-forming primaries, the satellite number density profile is consistent with power laws within projected distance 20<r_p<500 kpc. On the other hand, passively star forming primaries show flat profiles for 20<r_p<70 kpc, well fitted by generalized King models with a large core radius parameter (r_c ~ 68 kpc). In the external regions of the haloes (r_p>100 kpc), the density profiles of all primaries is well described by power laws, although we notice that for red, early spectral type primaries, the outer slope obtained is steeper than that corresponding to blue, late spectral type ones. We have tested our results by control samples of galaxies identical to the samples of satellites in apparent magnitude and projected distance to the primary, but with a large relative velocity. This sample of unphysical primary-galaxy pairs shows a flat radial density beyond r_p=20 kpc indicating that our results are not biased toward a decrease of the true number of objects due to catalogue selection effects. Our results can be understood in terms of dynamical friction and tidal stripping on satellites in the primary haloes. These processes can effectively transfer energy to the dark matter, flattening the central steep profiles of the satellite distribution in evolved systems.Comment: 8 pages, 6 figures. Accepted for publication in MNRA

The Evolution of K* and the Halo Occupation Distribution since z=1.5: Observations vs. Simulations

We study the evolution of the K-band luminosity function (LF) and the Halo Occupation Distribution (HOD) using Subaru observations of 15 X-ray clusters at z=0.8-1.5 and compare the results with mock clusters (0<z<1.3) extracted from the Millennium Simulation and populated with galaxies using the semi-analytic model (SAM) of Bower et al., matched in mass to our observed sample. We find that the characteristic luminosity K* defined by a Shechter LF is consistent with SAM predictions, which mimic well the evolution of K* in z>1 rich clusters. However, we cannot distinguish between this model and a simple stellar population synthesis model invoking passive evolution with a formation redshift z~5 - consistent with the presence of an old red galaxy population ubiquitous in rich clusters at z=1.5. We also see a small difference (\Delta K*~0.5) between our clusters and studies of the field population at similar redshifts, suggesting only a weak dependence of the luminous (L>L*) part of the LF on environment. Turning to our HOD study, we find that within R_{500}, high-z clusters tend to host smaller numbers of galaxies to a magnitude K*+2 compared to their low-z counterparts. This behavior is also seen in the mock samples and is relatively insensitive to the average mass of the cluster haloes. In particular, we find significant correlations of the observed number of member cluster galaxies (N) with both z and cluster mass: $N(M,z)=(53\pm1)(1+z)^{-0.61^{+0.18}_{-0.20}}(M/10^{14.3})^{0.86\pm0.05}$. Finally, we examine the spatial distribution of galaxies and provide a new estimate of the concentration parameter for clusters at high z ($c_{g}=2.8^{+1.0}_{-0.8}$). Our result is consistent with predictions from both our SAM mock clusters and literature's predictions for dark matter haloes. The mock sample predictions rise slowly with decreasing redshift reaching $c_{g}=6.3^{+0.39}_{-0.36}$ at z=0.Comment: 17 pages, 3 tables, 12 Figures. Accepted for publications in MNRAS. Version 2: modified Figs. 4, 8 and 1

On the dynamics of the satellite galaxies in NGC 5044

The NGC 5044 galaxy group is dominated by a luminous elliptical galaxy which is surrounded by ~160 dwarf satellites. The projected number density profile of this dwarf population deviates within ~1/3 of the virial radius from a projected NFW-profile, which is assumed to approximate the underlying total matter distribution. By means of a semi-analytic model we demonstrate that the interplay between gravitation, dynamical friction and tidal mass loss and destruction can explain the observed number density profile. We use only two parameters in our models: the total to stellar mass fraction of the satellite halos and the disruption efficiency. The disruption efficiency is expressed by a minimum radius. If the tidal radius of the galaxy (halo) falls below this radius the galaxies is assumed to become unobservable. The preferred parameters are an initial total to stellar mass fraction of ~20 and a disruption radius of 4 kpc. In that model about 20% of all the satellites are totally disrupted on their orbits within the group environment. Dynamical friction is less important in shaping the inner slope of the number density profile since the reduction in mass by tidal forces lowers the impact of the friction term. The main destruction mechanism is tide. In the preferred model the total B-band luminosity of all the disrupted galaxies is about twice the observed luminosity of the central elliptical galaxy, indicating that a significant fraction of stars are scattered into the intragroup medium.(Abridged)Comment: Accepted for publication in MNRAS, 7 pages, 5 figures, LaTeX (uses mn2e.cls