Spatially resolved LMC star formation history: I. Outside in evolution of the outer LMC disk

We study the evolution of three fields in the outer LMC disk Rgc=3.5-6.2 Kpc. Their star formation history indicates a stellar populations gradient such that younger stellar populations are more centrally concentrated. We identify two main star forming epochs, separated by a period of lower activity between ~7 and ~4 Gyr ago. Their relative importance varies from a similar amount of stars formed in the two epochs in the innermost field, to only 40% of the stars formed in the more recent epoch in the outermost field. The young star forming epoch continues to the present time in the innermost field, but lasted only till ~0.8 and 1.3 Gyr ago at Rgc=5.5 degrees and 7.1 degrees, respectively. This gradient is correlated with the measured HI column density and implies an outside-in quenching of the star formation, possibly related to a variation of the size of the HI disk. This could either result from gas depletion due to star formation or ram-pressure stripping, or from to the compression of the gas disk as ram-pressure from the Milky Way halo acted on the LMC interstellar medium. The latter two situations may have occurred when the LMC first approached the Milky Way.Comment: 15 pages, 13 figures, 4 tables. MNRAS, in pres

El metamorfismo hercínico de la Sierra de la Demanda (Provincias de Logroño y Burgos).

Se estudian los principales rasgos del metamorfismo hercínico de los materiales paleozoicos de la Sierra de la Demanda, en base a la caracterización de minerales arcillosos y micáceos. Asimismo, se considera su posible relación con otras áreas cercanas, con caracteres geológicos similares

Carbon star survey in the Local Group. VII. NGC 3109 a galaxy without a stellar halo

We present a CFH12K wide field survey of the carbon star population in and around NGC 3109. Carbon stars, the brightest members of the intermediate-age population, were found nearly exclusively in and near the disk of NGC 3109, ruling out the existence of an extensive intermediate-age halo like the one found in NGC 6822. Over 400 carbon stars identified have = -4.71, confirming the nearly universality of mean magnitude of C star populations in Local Group galaxies. Star counts over the field reveal that NGC 3109 is a truncated disk shaped galaxy without an extensive stellar halo. The minor axis star counts reach the foreground density between 4' and 5', a distance that can be explained by an inclined disk rather than a spheroidal halo. We calculate a global C/M ratio of 1.75 +/- 0.20, a value expected for such a metal poor galaxy.Comment: Accepted in Astronomy and Astrophysic

Passive cooling applicability mapping: A tool for designers

The applicability of passive cooling methods has been a recurring subject in architectural engineering science. The integration of these methods in architecture often requires feasibility studies and, in most cases, a deep knowledge of the climatic conditions is required to succeed in this task. The number of parameters to be evaluated will depend on the complexity of the cooling system, the physics involved and the context. This paper addresses the climatic applicability of convective and evaporative cooling systems in the context of United States (US) through the creation of a series of applicability maps deriving from processed climate data. This work is a revision of the climatic maps for downdraught cooling developed in Europe and in China with an extension to evaluate the opportunity for natural ventilation. More specifically, the studied cooling solutions are: Natural Convective Cooling (NCC), Passive Evaporative Cooling (PEC), and Active Downdraught Cooling (ADC). The maps obtained demonstrate the strong potential for the use of passive evaporative and convective cooling solutions in the US to overcome the current dependency on mechanical systems

A conceptual model for building design coordination using open source tools

Building Design Coordination is the process of communicating and integrating multidisciplinary designs into a single, coherent set of information that can be used for construction, to anticipate problems that would otherwise only be raised on the construction site. As projects grow in complexity and size, digital communication tools and other technological improvements have made it possible for physically distant design teams to collaborate in novel ways. More recently, BIM (Building Information Modelling), has opened even greater possibilities, although the design process nevertheless is often one of trial and error, demanding on each small change multiple possibilities to be considered, with decisions requiring to be validated among designers and other project stakeholders. Regardless of all the advantages that BIM has brought to the industry, testing for design changes in BIM models often requires a big effort and is a time-consuming activity that should be avoided whenever simpler processes can be used. Further developments on this study will propose a framework for building design coordination, using a non-relational graph database. The system can track design issues between unlimited users, organized into teams, handling formal project documents and keeping an historical record of the design development timeline. Since all the information regarding the design development process is stored in the form of Nodes and Relationships these can be intuitively be manipulated making it easier for teams to provide input on design decisions in real time with least cost impact to the project, providing at the same time access to pertinent information on the status of design issues and how the various stakeholders are contributing to the project. Through the use of reliable open source tools, a prototype can be implemented and made available to the industry professionals for testing, providing guidelines for modelling a Building Design Coordination system.info:eu-repo/semantics/publishedVersio

Formación del profesor en el enfoque de evaluación auténtica, garantiza el eficiente y eficaz proceso de evaluación para los aprendizajes por competencias de los estudiantes en el nivel superior

Objetivo General Con la aspiración y el propósito de alcanzar lo que se quiere en la. investigación1se expondrá de forma clara y precisa el objetivo general, que es la guía y luz de la misma: <Valorar la formación del profesor en el enfoque de evaluación auténtico, que garantice un eficiente y eficaz proceso de evaluación para los aprendizajes de los estudiantes por competencias en el nivel superior. Objetivos Específicos Con los objetivos específicos se conoce lo que hay que realizar en cada una de las etapas de la investigación que se reflejan en los logros parciales de cada fase, van a facilitar el control sistemático del trabajo investigativo, al ser alcanzados en conjunto garantizan el logro del objetivo general: <Examinar la información referente a la formación que poseen los profesores en 'd enfoque de evaluación auténtica: <Reconocer la participación del profesor en jornadas de capacitación, actualización, referente al enfoque de evaluación auténtica. <Detectar la participación del profesor en actividades de coordinaciones de proyectos y programas, asesorías y jurados de tesis, otras. <Verificar la utilización del enfoque de evaluación auténtica, por el profesor universitario para la evaluación de los aprendizajes desarrollados por Competencias del estudiante del nivel superior. <Determinar la necesidad de capacitación del profesor universitario en cuanto al, enfoque auténtico de evaluación para los aprendizajes

Copy-back viral genomes induce a cellular stress response that interferes with viral protein expression without affecting antiviral immunity

Antiviral responses are often accompanied by translation inhibition and formation of stress granules (SGs) in infected cells. However, the triggers for these processes and their role during infection remain subjects of active investigation. Copy-back viral genomes (cbVGs) are the primary inducers of the mitochondrial antiviral signaling (MAVS) pathway and antiviral immunity during Sendai virus (SeV) and respiratory syncytial virus (RSV) infections. The relationship between cbVGs and cellular stress during viral infections is unknown. Here, we show that SGs form during infections containing high levels of cbVGs, and not during infections with low levels of cbVGs. Moreover, using RNA fluorescent in situ hybridization to differentiate accumulation of standard viral genomes from cbVGs at a single-cell level during infection, we show that SGs form exclusively in cells that accumulate high levels of cbVGs. Protein kinase R (PKR) activation is increased during high cbVG infections and, as expected, is necessary for virus-induced SGs. However, SGs form independent of MAVS signaling, demonstrating that cbVGs induce antiviral immunity and SG formation through 2 independent mechanisms. Furthermore, we show that translation inhibition and SG formation do not affect the overall expression of interferon and interferon stimulated genes during infection, making the stress response dispensable for global antiviral immunity. Using live-cell imaging, we show that SG formation is highly dynamic and correlates with a drastic reduction of viral protein expression even in cells infected for several days. Through analysis of active protein translation at a single-cell level, we show that infected cells that form SGs show inhibition of protein translation. Together, our data reveal a new cbVG-driven mechanism of viral interference where cbVGs induce PKR-mediated translation inhibition and SG formation, leading to a reduction in viral protein expression without altering overall antiviral immunity

The influence of heavy goods vehicle traffic on accidents on different types of Spanish interurban roads

This paper illustrates a methodology developed to analyze the influence of traffic conditions, i.e. volume and composition on accidents on different types of interurban roads in Spain, by applying negative binomial models. The annual average daily traffic was identified as the most important variable, followed by the percentage of heavy goods vehicles, and different covariate patterns were found for each road type. The analysis of hypothetical scenarios of the reduction of heavy goods vehicles in two of the most representative freight transportation corridors, combined with hypotheses of total daily traffic mean intensity variation, produced by the existence or absence of induced traffic gives rise to several scenarios. In all cases a reduction in the total number of accidents would occur as a result of the drop in the number of heavy goods transport vehicles, However the higher traffic intensity, resulting of the induction of other vehicular traffic, reduces the effects on the number of accidents on single carriageway road segments compared with high capacity roads, due to the increase in exposure. This type of analysis provides objective elements for evaluating policies that encourage modal shifts and road safety enhancements

The Chemical Enrichment History of the Large Magellanic Cloud

Ca II triplet spectroscopy has been used to derive stellar metallicities for individual stars in four LMC fields situated at galactocentric distances of 3\arcdeg, 5\arcdeg, 6\arcdeg\@ and 8\arcdeg\@ to the north of the Bar. Observed metallicity distributions show a well defined peak, with a tail toward low metallicities. The mean metallicity remains constant until 6\arcdeg\@ ([Fe/H]$\sim$-0.5 dex), while for the outermost field, at 8\arcdeg, the mean metallicity is substantially lower than in the rest of the disk ([Fe/H]$\sim$-0.8 dex). The combination of spectroscopy with deep CCD photometry has allowed us to break the RGB age--metallicity degeneracy and compute the ages for the objects observed spectroscopically. The obtained age--metallicity relationships for our four fields are statistically indistinguishable. We conclude that the lower mean metallicity in the outermost field is a consequence of it having a lower fraction of intermediate-age stars, which are more metal-rich than the older stars. The disk age--metallicity relationship is similar to that for clusters. However, the lack of objects with ages between 3 and 10 Gyr is not observed in the field population. Finally, we used data from the literature to derive consistently the age--metallicity relationship of the bar. Simple chemical evolution models have been used to reproduce the observed age--metallicity relationships with the purpose of investigating which mechanism has participated in the evolution of the disk and bar. We find that while the disk age--metallicity relationship is well reproduced by close-box models or models with a small degree of outflow, that of the bar is only reproduced by models with combination of infall and outflow.Comment: 45 pages, 10 figures, accepted for publication in Astronomical Journa