On the Nature of Fossil Galaxy Groups: Are they really fossils ?

We use SDSS-DR4 photometric and spectroscopic data out to redshift z~0.1 combined with ROSAT All Sky Survey X-ray data to produce a sample of twenty-five fossil groups (FGs), defined as bound systems dominated by a single, luminous elliptical galaxy with extended X-ray emission. We examine possible biases introduced by varying the parameters used to define the sample and the main pitfalls are discussed. The spatial density of FGs, estimated via the V/V_ MAX} test, is 2.83 x 10^{-6} h_{75}^3 Mpc^{-3} for L_x > 0.89 x 10^42 h_{75}^-2 erg/s consistent with Vikhlinin et al. (1999), who examined an X-ray overluminous elliptical galaxy sample (OLEG). We compare the general properties of FGs identified here with a sample of bright field ellipticals generated from the same dataset. These two samples show no differences in the distribution of neighboring faint galaxy density excess, distance from the red sequence in the color-magnitude diagram, and structural parameters such as a$_{4}$ and internal color gradients. Furthermore, examination of stellar populations shows that our twenty-five FGs have similar ages, metallicities, and $\alpha$-enhancement as the bright field ellipticals, undermining the idea that these systems represent fossils of a physical mechanism that occurred at high redshift. Our study reveals no difference between FGs and field ellipticals, suggesting that FGs might not be a distinct family of true fossils, but rather the final stage of mass assembly in the Universe.Comment: 18 pages, Accepted to A

Associated factors to the control Of cardiovascular risk in a low-income population from the caribbean region of Colombia

To identify associated factors to the control of blood pressure (BP), low-density lipoprotein cholesterol (LDL) and glycated hemoglobin (hba1c) in a low-income population from the Caribbean region of Colombia, enrolled in “De todo corazón -DTC” program between 2013-201

Effectiveness of a cardiovascular disease prevention program in the control of cardiovascular risk factors in a low-income population from the caribbean region of Colombia

To evaluate the effectiveness of a cardiovascular disease prevention program in the control of cardiovascular risk factors in a low-income population from the Caribbean region of Colombi

SPIDER - IV. Optical and NIR color gradients in Early-type galaxies: New Insights into Correlations with Galaxy Properties

We present an analysis of stellar population gradients in 4,546 Early-Type Galaxies with photometry in $grizYHJK$ along with optical spectroscopy. A new approach is described which utilizes color information to constrain age and metallicity gradients. Defining an effective color gradient, $\nabla_{\star}$, which incorporates all of the available color indices, we investigate how $\nabla_{\star}$ varies with galaxy mass proxies, i.e. velocity dispersion, stellar (M_star) and dynamical (M_dyn) masses, as well as age, metallicity, and alpha/Fe. ETGs with M_dyn larger than 8.5 x 10^10, M_odot have increasing age gradients and decreasing metallicity gradients wrt mass, metallicity, and enhancement. We find that velocity dispersion and alpha/Fe are the main drivers of these correlations. ETGs with 2.5 x 10^10 M_odot =< M_dyn =< 8.5 x 10^10 M_odot, show no correlation of age, metallicity, and color gradients wrt mass, although color gradients still correlate with stellar population parameters, and these correlations are independent of each other. In both mass regimes, the striking anti-correlation between color gradient and alpha-enhancement is significant at \sim 4sigma, and results from the fact that metallicity gradient decreases with alpha/Fe. This anti-correlation may reflect the fact that star formation and metallicity enrichment are regulated by the interplay between the energy input from supernovae, and the temperature and pressure of the hot X-ray gas in ETGs. For all mass ranges, positive age gradients are associated with old galaxies (>5-7 Gyr). For galaxies younger than \sim 5 Gyr, mostly at low-mass, the age gradient tends to be anti-correlated with the Age parameter, with more positive gradients at younger ages.Comment: Accepted for Publication in the Astronomical Journa

Effectiveness of a cardiovascular risk management program in reducing the probability of premature death due to cardiovascular events in the Colombian caribbean region

Effectiveness of a cardiovascular risk management program in reducing the probability of premature death due to cardiovascular events in the Colombian Caribbean regio

Obsolescence in the neighbourhood of Nuestra Señora del Carmen

Actualmente, áreas urbanas donde habita un importantísimo sector poblacional están afectadas por una compleja problemática que se materializa en cuestiones arquitectónicas (desencaje tipológico, deficiencias técnicas, deterioro físico), urbanísticas (aislamiento, carencias funcionales, degradación del espacio público) y sociales (desempleo, segregación, conflictividad). El análisis del estado de obsolescencia de la barriada de El Carmen ha sido el punto de inicio de este trabajo de investigación. A partir de indicadores de obsolescencia socioeconómicos y físicos, anteriormente definidos por el proyecto de investigación «Intervención en barriadas residenciales obsoletas: manual de buenas prácticas» (G-GI3001/IDIH), financiado por la Unión Europea –Fondos FEDER– y gestionado por la Consejería de Fomento y Vivienda de la Junta de Andalucía, se ha establecido la situación de la barriada con referencia a valores máximos y mínimos, hallados a través del estudio de un número representativo de barriadas andaluzas. Tras la valoración del estado de obsolescencia de la barriada, se profundizó en su estudio a través de la comparación del cumplimiento de las recomendaciones establecidas como buenas prácticas en la publicación Intervención en barriadas residenciales obsoletas. Manual de buenas prácticas. Esta verificación permitió la elaboración de un diagnóstico pormenorizado basado en el análisis de los diferentes aspectos atendidos por las buenas prácticas, donde se evaluaban las deficiencias de El Carmen a escala urbana y arquitectónica, y dentro de estas, en diferentes categorías, siendo las urbanas: compacidad, conectividad, zonas verdes, funcionalidad, seguridad e inclusividad; y las arquitectónicas: hibridación, diversidad y flexibilidad, comunidad y accesibilidad. Esta evaluación detallada de las deficiencias y potencialidades de la barriada establecía los fundamentos para la definición de criterios y estrategias de intervención. Estos criterios de intervención tenían como base una selección de las buenas prácticas más adecuadas de acuerdo con las circunstancias halladas en la barriada, sistematizando las actuaciones que priorizan la atención de aspectos primordiales o que actúan mitigando carencias graves. Los criterios que se establecen son: sostenibilidad, la mejora de la calidad de vida de sus residentes y la atracción de nueva población a la barriada. Respondiendo a este estudio y la definición de criterios se proponen actuaciones estratégicas englobadas en cuatro líneas de trabajo: relación con la ciudad y su contexto, cualificación del espacio público y dotaciones existentes, cualificación de edificios existentes y actualización tipológica.Today, a number of high-occupancy urban areas are being affected by a complex problem that materialises in architectural issues (typological mismatch, technical deficiencies, physical deterioration), urban planning issues (isolation, functional inadequacies, deterioration of public space) and social issues (unemployment, segregation, conflict). Analysing the state of obsolescence of the neighbourhood of El Carmen was the starting point of this research project. Using socio-economic and physical obsolescence indicators established in an earlier research project–“Intervention in Obsolete Residential Neighbourhoods: Manual of Best Practices” (G-GI3001/IDIH), funded by the ERDF and managed by the Regional Ministry of Public Works and Housing of Andalusia–the situation of this neighbourhood was defined with reference to minimum and maximum values identified by studying a representative number of Andalusian neighbourhoods. After assessing the neighbourhood’s state of obsolescence, it was then studied to determine the degree of compliance with the best practices recommended in the publication Intervención en barriadas residenciales obsoletas. Manual de buenas prácticas. This verification made it possible to come up with a detailed diagnosis based on the analysis of different aspects addressed in that manual of best practices, evaluating the urban and architectural deficiencies of El Carmen and subdividing each into different categories. Urban deficiencies included compactness, connectivity, green areas, functionality, safety and inclusiveness; and architectural deficiencies were hybridisation, diversity, flexibility, community and accessibility. This detailed analysis of the neighbourhood’s shortcomings and potential improvements provided a solid foundation for defining intervention criteria and strategies. Those intervention criteria were based on a selection of the best practices deemed most appropriate in light of the neighbourhood’s current situation, systematising actions that address the most important aspects or attempt to mitigate serious deficiencies. The established criteria are as follows: sustainability, improving the residents’ quality of life, and bringing new residents to the neighbourhood. Based on this study and the defined criteria, strategic courses of action were proposed in four general areas: relationship with the city and its context, qualification of existing facilities and public spaces, qualification of existing buildings, and typological modernisation

The QUIJOTE experiment: project overview and first results

QUIJOTE (Q-U-I JOint TEnerife) is a new polarimeter aimed to characterize the polarization of the Cosmic Microwave Background and other Galactic and extragalactic signals at medium and large angular scales in the frequency range 10-40 GHz. The multi-frequency (10-20~GHz) instrument, mounted on the first QUIJOTE telescope, saw first light on November 2012 from the Teide Observatory (2400~m a.s.l). During 2014 the second telescope has been installed at this observatory. A second instrument at 30~GHz will be ready for commissioning at this telescope during summer 2015, and a third additional instrument at 40~GHz is now being developed. These instruments will have nominal sensitivities to detect the B-mode polarization due to the primordial gravitational-wave component if the tensor-to-scalar ratio is larger than r=0.05.Comment: To appear in "Highlights of Spanish Astrophysics VIII", Proceedings of the XI Scientific Meeting of the Spanish Astronomical Society, Teruel, Spain (2014

QUIJOTE-CMB experiment: a technical overview

The QUIJOTE-CMB experiment (Q-U-I JOint TEnerife CMB experiment) is an ambitious project to obtain polarization measurements of the sky microwave emission in the 10 to 47 GHz range. With this aim, a pair of 2,5m telescopes and three instruments are being sited at the Teide Observatory, in Tenerife (Canary Islands, Spain). The first telescope and the first instrument (the MFI: Multi Frequency Instrument) are both already operating in the band from 10 to 20 GHz, since November 2012. The second telescope and the second instrument (TGI: Thirty GHz instrument) is planned to be in commissioning by the end of summer 2014, covering the range of 26 to 36 GHz. After that, a third instrument named FGI (Forty GHz instrument) will be designed and manufactured to complete the sky survey in the frequency range from 37 to 47 GHz. In this paper we present an overview of the whole project current status, from the technical point of view

QUIJOTE Experiment: status of telescopes and instrumentation

The QUIJOTE Experiment (Q-U-I JOint TEnerife) is a combined operation of two telescopes and three instruments working in the microwave band to measure the polarization of the Cosmic Microwave Background (CMB) from the northern hemisphere, at medium and large angular scales. The experiment is located at the Teide Observatory in Tenerife, one of the seven Canary Islands (Spain). The project is a consortium maintained by several institutions: the Instituto de Astrofísica de Canarias (IAC), the Instituto de Física de Cantabria (IFCA), the Communications Engineering Department (DICOM) at Universidad de Cantabria, and the Universities of Manchester and Cambridge. The consortium is led by the IAC