Searching for emission-line galaxies: The UCM survey

We are carrying out a long-term project with the main purposes of finding and analyzing low metallicity galaxies. A very small number of very low metallicity galaxies is known up to now. However these ojbects are particularly interesting since they are excellent candidates to 'young galaxies' in evolutionary sense as POX186 (Kunth, Maurogordato & Vigroux, 1988). Since the interstellar matter in these objects is only weakly contaminated by stellar evolution, their study could provide valuable information about the primordial helium abundance and therefore it could place constraints on the different Big-Bang models. The instrumental set up of our survey is an objective-prism used with the Schmidt telescope at Calar Alto Observatory. By using hypersensitized IIIaF emulsion and RG630 filter low resolution spectra in the H alpha region of objects in a wide field is obtained (Rego et al. 1989, Zamorano et al. 1990). Surveys carried out in the past two decades at optical blue wavelengths have also produced large samples of emission-line galaxies (ELGs), for example MacAlpine & Willians 1981 and reference therein, Wasilewski 1983, Salzer and MacAlpine 1988, or Smith et al. 1976. Relying primarily on objective-prism plates taken in the blue, these surveys have found over 3000 blue/emission-line galaxies so far. A significant number of star-forming galaxies are missed by optical surveys in the blue because of their low-excitation spectra (MacAlpine and Willians 1981, Markarian et al. 1981 and references therein) or their low metallicity (Kunth and Sargent, 1986)

Los locutorios como espacios de integración : las tecnologías de la información y la comunicación en la construcción de redes e identidades

Resum.La acelerada y masiva implementación de las TIC en las sociedades contemporáneas pone de manifiesto el papel cada vez más relevante que éstas están tomando, no sólo como medio de acceso a la información, sino especialmente como forma de integración y participación ciudadana en un mundo de carácter glocal. De ahí que los espacios de acceso público a las TIC (cibercafés, bibliotecas, telecentros o locutorios) aparezcan como enclaves esenciales en los que indagar el impacto social que producen las nuevas tecnologías en sujetos y colectivos, así como para analizar las apropiaciones que sus usuarios/as hacen de las TIC, especialmente aquellas dirigidas a generar y consolidar redes sociales. En este artículo, tras revisar la literatura científico-social de los principales lugares de acceso público a TIC, nos acercaremos concretamente a los espacios denominados locutorios, tratando sus características y las formas específicas de vinculación y relación que sus usuarios/as más frecuentes, la población migrante, establece en ellos. De esta forma, el locutorio es tratado como un lugar-metáfora de los procesos migratorios en un mundo globalizado. En la discusión defenderemos el concepto de estación de asociaciones como útil antropológico para caracterizarlosIt's clear that the accelerated and massive implementation in contemporary societies of ICTs makes their role ever more relevant, not just as means of information access but especially insofar as the role they play in forming citizen integration and participation modes that have a glocal character. Hence, public ICT access spaces (cybercafés, libraries, telecenters, or public call centers (locutorios)) appear to be essential enclaves where one can investigate the social impact produced by these new technologies on subjects and collectives, as well as to analyze how users put them to use, particularly those ICTs aimed at the promotion and consolidation of social networks. This article first offers a review of the scientific-social literature focused on the principal public ICT access spaces. It treats the specific characteristics and means of the links and relationships frequent users, the immigrant population, establish in the public call center. As such, it is treated as a place-metaphor for migratory processes in a globalized world. The discussion defends the concept of association stations as an anthropological tool to help elucidate the characteristics of this space

El acceso público a las tecnologías de la información y la comunicación : el lugar de los locutorios en los procesos migratorios

En los últimos años han surgido en nuestras ciudades diferentes espacios que ofrecen servicios de acceso a las nuevas Tecnologías de la Información y la Comunicación. En este artículo nos centramos específicamente en los locutorios, lugares de acceso a las TIC y también a la telefonía convencional, que tienen mayoritariamente como usuarios/as a la población migrante y en movimiento. Hemos realizado un estudio cualitativo de tipo etnográfico, en el que se han aplicado técnicas de observación participante, entrevistas y grupos de discusión. Los resultados muestran que los locutorios, lejos de ser únicamente espacios que posibilitan el establecimiento y mantenimiento de vínculos a distancia, también articulan las relaciones in situ, conformándose como lugares de encuentro, esto es, como estación de asociaciones. Así, presentamos al locutorio como metáfora de la inmigración, ya que nos permite dar cuenta de su carácter nacional y transnacional, así como de las redes familiares y prácticas sociales que se generan en estos espacios sociotécnicoVarious places that offer access to new Information and Communication Technologies (ICT) have emerged in our cities in recent years. In this paper we focus specifically on the "locutorios" (call centers), places of access to ICT and also to conventional telephony. Users are mostly the migrant and in motion population. We conducted a qualitative ethnographic study, which have applied techniques of participant observation, interviews and discussion groups. The results show that call centers are not only spaces to enable the establishment and maintenance of links to distance, but also allow space for relationships in situ. This makes the "locutorios" (call centers) meeting places, that is, associations stations. We present the "locutorios" (call centres) as a metaphor for immigration, because it allows us to account for their national and transnational character. It also allows us to account for the family networks and social practices that are generated in these sociotechnical spaces

Towards a Precision Cosmology from Starburst Galaxies at z>2

This work investigates the use of a well-known empirical correlation between the velocity dispersion, metallicity, and luminosity in H beta of nearby HII galaxies to measure the distances to HII-like starburst galaxies at high redshifts. This correlation is applied to a sample of 15 starburst galaxies with redshifts between z=2.17 and z=3.39 to constrain Omega_m, using data available from the literature. A best-fit value of Omega_m = 0.21 +0.30 -0.12 in a Lambda-dominated universe and of Omega_m = 0.11 +0.37 -0.19 in an open universe is obtained. A detailed analysis of systematic errors, their causes, and their effects on the values derived for the distance moduli and Omega_m is carried out. A discussion of how future work will improve constraints on Omega_m by reducing the errors is also presented.Comment: 7 pages, 3 figures, accepted for publication in MNRA

Women\u27s experiences on the path to a career in game development

This chapter seeks to identify whether there is a dominant, presupposed career pipeline to a career in game development and then looks for women and women’s experiences at each stage of that pipeline. It concludes that a dominant pipeline does exist and that this pathway both disadvantages women who attempt it and marginalizes other pathways. Along the way women deal with obstacles that can delegitimize their choices and experiences and/or make the assumed pathway inhospitable. This chapter relies on published literature as well as data from the 2014 and 2015 Developer Satisfaction Surveys (DSS) conducted by the International Game Developers Association (IGDA) in partnership with the authors

ISO observations of the Wolf-Rayet galaxies NGC 5430, NGC 6764, Mrk 309 and VII Zw 19

Observations of four WR galaxies (NGC 5430, NGC 6764, Mrk 309 and VII Zw 19) using the Infrared Space Observatory are presented here. ISOCAM maps of NGC 5430, Mrk 309 and NGC 6764 revealed the location of star formation regions in each of these galaxies. ISOPHOT spectral observations from 4 to 12 microns detected the ubiquitous PAH bands in the nuclei of the targets and several of the disk star forming regions, while LWS spectroscopy detected [OI] and [CII] emission lines from two galaxies, NGC 5430 and NGC 6764. Using a combination of ISO and IRAS flux densities, a dust model based on the sum of modified blackbody components was successfully fitted to the available data. These models were then used to calculate new values for the total IR luminosities for each galaxy, the size of the various dust populations, and the global SFR. The derived flux ratios, the SFRs, the high L(PAH)/L(40-120 microns) and F(PAH 7.7 microns)/F(7.7 microns continuum) values suggest that most of these galaxies are home to only a compact burst of star formation. The exception is NGC 6764, whose F(PAH 7.7 microns)/F(7.7 microns continuum) value of 1.22 is consistent with the presence of an AGN, yet the L(PAH)/L(40-120 microns) is more in line with a starburst, a finding in line with a compact low-luminosity AGN dominated by the starburst

Hindbrain raphe stimulation boosts cyclic adenosine monophosphate and signaling proteins in the injured spinal cord

Early recovery from incomplete spinal cord contusion is improved by prolonged stimulation of the hindbrain's serotonergic nucleus raphe magnus (NRM). Here we examine whether increases in cyclic adenosine monophosphate (cAMP), an intracellular signaling molecule with several known restorative actions on damaged neural tissue, could play a role. Subsequent changes in cAMP-dependent phosphorylation of protein kinase A (PKA) and PKA-dependent phosphorylation of the transcription factor "cAMP response element-binding protein" (CREB) are also analyzed. Rats with moderate weight-drop injury at segment T8 received 2h of NRM stimulation beginning three days after injury, followed immediately by separate extraction of cervical, thoracic and lumbar spinal cord for immunochemical assay. Controls lacked injury, stimulation or both. Injury reduced cAMP levels to under half of normal in all three spinal regions. NRM stimulation completely restored these levels, while producing no significant change in non-injured rats. Pretreatment with the 5-HT7 receptor antagonist pimozide (1 mg/kg, intraperitoneal) lowered cAMP in non-injured rats to injury amounts, which were unchanged by NRM stimulation. The phosphorylated fraction of PKA (pPKA) and CREB (pCREB) was reduced significantly in all three regions after SCI and restored by NRM stimulation, except for pCREB in lumbar segments. In conclusion, SCI produces spreading deficits in cAMP, pPKA and pCREB that are reversible by Gs protein-coupled 5-HT receptors responding to raphe-spinal activity, although these signaling molecules are not reactive to NRM stimulation in normal tissue. These findings can partly explain the benefits of NRM stimulation after SCI

Observations of a complete sample of H

Spectroscopic observations for the full sample of Hα emission–line galaxy candidates (ELGs) from the Universidad Complutense de Madrid objective-prism survey Lists 1 and 2 have been obtained in order to investigate fully the properties of the survey constituents as well as the selection characteristics and completeness limits of the survey itself. The spectroscopic data include redshifts, line fluxes, equivalent widths, emission-line ratios, optical reddening estimates and synthesized color indexes. We find that 74% of the objects in this sample do exhibit emission lines. We compare our observational data with parameters given in the published survey lists in order to assess the usefulness of the latter. The different emission-line galaxies have been classified according to their spectra in several groups. Gray-scale images of the CCD spectra near the main emission lines, spatial profiles at the continuum and the line for [OIII] λ5007 and Hα lines, as well as plots of the coadded spectra of selected galaxies are presented, and a number of peculiar objects are described