Structure of non-unital purely infinite simple rings

In this note, we study the notion of purely infinite simple ring in the case of nonunital rings, and we obtain an analog to Zhang's Dichotomy for σ-unital purely infinite simple C*-algebras in the purely algebraic context

Synchrotron X-ray microdiffraction to study dental structures in Cretaceous crocodylomorphs

Synchrotron radiation X-ray microdiffraction (SR-μXRD) has been applied for the first time as a fundamental method of analysis to unveil crocodilian teeth growth and development. Teeth from a fossil crocodylomorph from the Upper Cretaceous site of Lo Hueco (Spain) and a modern crocodylian from the living species Crocodylus niloticus have been analysed. Both samples have been studied through Polarized Light Microscopy, Scanning Electron Microscopy coupled with Energy Dispersive X-Ray Spectroscopy, Confocal Raman Spectroscopy, and SR-μXRD. Significant differences have been found in hydroxyapatite (HA) crystallite sizes and texture, and the evolution of these two features along teeth depth. The main differences observed in crystallite size are related to postdepositional processes and/or the environmental and functional pressures of teeth during crocodylomorph life, very different from that of the modern specimen. Regarding the crystalline texture in the tooth enamel, it can be linked to teeth functionality during crocodilian life, causing the directed growth of HA crystallites due to the mechanical stress to which they are subjectedThis work was funded by the projects PGC2018-099405-B-100 (Ministerio de Ciencia, Innovacion y Universidades); HAR2017- 82755-P, HAR2016-78036-P, HAR2016-74846-P, HAR2017-83004-P, CGL2015-66604, CGL2015-68363 and MAT2015-67593-P (Ministerio de Economía y Competitividad, Spain); and 201860E127 (CSIC

Estrategias expresivas, interdisciplinariedad y convivencia desde la Educación Musical

El Proyecto “Estrategias expresivas, interdisciplinariedad y convivencia desde la Educación Musical” activo desde el curso 2013-2014, pretende incidir de forma especial en algunos aspectos abordados en los años anteriores, privilegiando la participación de las diferentes disciplinas que conviven en el campo educativo. A partir de la experimentación y mediante el trabajo sobre algunos aspectos comunes a distintas disciplinas como las matemáticas, la literatura y la música, el alumnado se acerca al conocimiento de las posibilidades expresivas de cada una de ellas, poniendo en valor la interdisciplinariedad. Todas estas implicaciones motivan al grupo a generar espacios de convivencia mediante un aprendizaje basado en la resolución de problemas (ABP); además, se potencia el aprendizaje por proyectos priorizando las tareas colaborativas y profundizando en aprendizajes experimentales. Este Proyecto se concreta a partir de iniciativas puntuales como la participación en actividades literarias, musicales y experimentales -matemáticas- realizadas tanto en los centros participantes como en instituciones educativas del medio. La colaboración con el Área de Lengua y Literatura se define en sesiones de interpretación de poesía y música y en un taller de redacción de trabajos académicos. Se incorpora la creación de un Blog como recurso tecnológico educativo, a la vez que herramienta de comunicación, colaboración y de construcción del aprendizaje. Finalmente se busca promover un alumnado crítico y activo en su formación profesional, tanto en el ámbito de la docencia (Facultad de Formación del Profesorado) como en el de la Musicología y áreas afines (Facultad de Filosofía y Letras). La comunicación conjunta de parte del grupo de Innovación presentará los avances y logros de los principales objetivos propuestos, atendiendo a la idoneidad de la utilización de la música como herramienta expresiva e interdisciplinar

USCID fourth international conference

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Includes bibliographical references.This study, carried out between October 2004 and November 2005 on the island of Tenerife, covers: (1) characterization of the irrigated crops and quantification of the gross irrigation requirements (GIRs) of each crop using surveys; (2) field evaluation of drip/micro, spray and sprinkle irrigation systems to obtain global distribution uniformity (DU) as indicated by the Cal Poly ITRC (Irrigation Training and Research Centre, California Polytechnic State University, San Luis Obispo, California, USA); (3) analysis of on farm irrigation efficiency using local climatic data; and (4) inclusion of this data into a Geographic Information System (GIS). Crop GIRs show high deviations mainly because of the multiple microclimate conditions on the island, the irrigation methods used, the crop systems (greenhouses, etc) and the irrigation management. Field evaluation provided an average DU of 0.83 in drip/micro and spray irrigated banana crops, 0.69 in sprinkle irrigated ones, 0.58 in sprinkle irrigated horticulture and 0.81 for tomato crops (100% drip). Data showed that approximately 30% of the non-uniformity was due to pressure differences in the irrigation system, 3% due to unequal drainage, 7% due to unequal application rates, and 60% was due to other causes (which include manufacturing variation, plugging, and wear). Irrigation efficiency is around 80% in drip irrigated tomato and banana crops and 75% in sprinkle systems. Data showed that efficiency is slightly lower in greenhouses and mesh greenhouse crops than in non-protected crops basically due to the fact that although protected crops require less water, they receive an equal quantity of water. Inclusion of the data into a GIS makes possible a high level of agronomic water consumption control on the island

Ultrametric spaces of branches on arborescent singularities

Let $S$ be a normal complex analytic surface singularity. We say that $S$ is arborescent if the dual graph of any resolution of it is a tree. Whenever $A,B$ are distinct branches on $S$, we denote by $A \cdot B$ their intersection number in the sense of Mumford. If $L$ is a fixed branch, we define $U_L(A,B)= (L \cdot A)(L \cdot B)(A \cdot B)^{-1}$ when $A \neq B$ and $U_L(A,A) =0$ otherwise. We generalize a theorem of P{\l}oski concerning smooth germs of surfaces, by proving that whenever $S$ is arborescent, then $U_L$ is an ultrametric on the set of branches of $S$ different from $L$. We compute the maximum of $U_L$, which gives an analog of a theorem of Teissier. We show that $U_L$ encodes topological information about the structure of the embedded resolutions of any finite set of branches. This generalizes a theorem of Favre and Jonsson concerning the case when both $S$ and $L$ are smooth. We generalize also from smooth germs to arbitrary arborescent ones their valuative interpretation of the dual trees of the resolutions of $S$. Our proofs are based in an essential way on a determinantal identity of Eisenbud and Neumann.Comment: 37 pages, 16 figures. Compared to the first version on Arxiv, il has a new section 4.3, accompanied by 2 new figures. Several passages were clarified and the typos discovered in the meantime were correcte

First survey of Wolf-Rayet star populations over the full extension of nearby galaxies observed with CALIFA

The search of extragalactic regions with conspicuous presence of Wolf-Rayet (WR) stars outside the Local Group is challenging task due to the difficulties in detecting their faint spectral features. In this exploratory work, we develop a methodology to perform an automated search of WR signatures through a pixel-by-pixel analysis of integral field spectroscopy (IFS) data belonging to the Calar Alto Legacy Integral Field Area survey, CALIFA. This technique allowed us to build the first catalogue of Wolf-Rayet rich regions with spatially-resolved information, allowing to study the properties of these complexes in a 2D context. The detection technique is based on the identification of the blue WR bump (around He II 4686 {\AA}, mainly associated to nitrogen-rich WR stars, WN) and the red WR bump (around C IV 5808 {\AA} and associated to carbon-rich WR stars, WC) using a pixel-by-pixel analysis. We identified 44 WR-rich regions with blue bumps distributed in 25 galaxies of a total of 558. The red WR bump was identified only in 5 of those regions. We found that the majority of the galaxies hosting WR populations in our sample are involved in some kind of interaction process. Half of the host galaxies share some properties with gamma-ray burst (GRB) hosts where WR stars, as potential candidates to being the progenitors of GRBs, are found. We also compared the WR properties derived from the CALIFA data with stellar population synthesis models, and confirm that simple star models are generally not able to reproduce the observations. We conclude that other effects, such as the binary star channel (which could extend the WR phase up to 10 Myr), fast rotation or other physical processes that causes the loss of observed Lyman continuum photons, are very likely affecting the derived WR properties, and hence should be considered when modelling the evolution of massive stars.Comment: 33 pages, accepted for publication in A&

IMF - metallicity: a tight local relation revealed by the CALIFA survey

Variations in the stellar initial mass function (IMF) have been invoked to explain the spectroscopic and dynamical properties of early-type galaxies. However, no observations have yet been able to disentangle the physical driver. We analyse here a sample of 24 early-type galaxies drawn from the CALIFA survey, deriving in a homogeneous way their stellar population and kinematic properties. We find that the local IMF is tightly related to the local metallicity, becoming more bottom-heavy towards metal-rich populations. Our result, combined with the galaxy mass-metallicity relation, naturally explains previous claims of a galaxy mass-IMF relation, derived from non-IFU spectra. If we assume that - within the star formation environment of early-type galaxies - metallicity is the main driver of IMF variations, a significant revision of the interpretation of galaxy evolution observables is necessary.Comment: Accepted for publication in ApJL. 6 pages, 4 figure

Estrategias expresivas, interdisciplinariedad y convivencia desde la Educación Musical

The Project “Expressive strategies, interdisciplinary nature and conviviality from  Musical Education” arises from the initiative of a group of teachers of the Music Area  who teach music in the Teaching Degree in Early Childhood Education, Teacher Elementary Grade, Teaching Degree in Primary with Distinction in Music, M. Marcela González Barroso being the head of the project. Its main objective is to inter-relate the subjects of Music and their didactic application and Development of the Musical Expression with the materials being part of the Distinction in Music. All of them will be coordinated, in turn, with other subjects of the degree that are invited to cooperate in the development of the project. For the participating teachers the implementation of this project means an important advance in the cooperative conception of university education which affects a high number of students.For the students linked to this project it means optimal integration of their academic efforts, since the Project is born, on the one hand, from the needs raised by the Mention in Music and its curricular organization, since those who chose it need to develop skills and capacities of a solvent professional in the artistic-musical field in a short time. On the other hand, and through their participation, the teachers being trained will value the incorporation of music as an interdisciplinary tool which is useful to improve the learning of other subjects; additionally, they will know the expressive possibilities of artistic language as a generator of coexisting spaces, the other central concept of the Project. Ultimately, through learning based on problem-solving, or with participation in cooperative tasks, the students will deepen in experimental learning, performing organizational roles, cooperating with each other and optimising the time available to develop the proposed objectives.This Project will be implemented from two initiatives: an artistic-musical and another with research characteristics. The first one proposes Work/s that may include singing, dancing, instrumental practice, and the second proposes an analysis of the artistic activities quoted and the processes involved in them. Both suggestions will be projected towards the education community, which entails that the students the living out and experimentation of initiatives which will prepare them as managers of projects and activities, in direct relation with the specific skills of the degrees. For the commissioning and presentation of the artistic aspect of innovation, we will take considered contributions of authors such as Karl Orff, Murray Schafer, Sinichi Suzuki, Silvia Malbrán, Ana Lucía Frega, among others. For the section of the project focused on research, the methodologies will be the traditional, research and analysis of primary and secondary sources, field work, and elaboration of surveys, anecdote records and interviews.El Proyecto de Innovación <Ad Honorem> de la Universidad de Oviedo (España) titulado “Estrategias expresivas, interdisciplinariedad y convivencia desde la Educación Musical”, PINN –13-019 -y del que es Responsable la M. Marcela González Barroso- surge a partir de la iniciativa de un grupo de profesoras del Área de Música que imparten docencia en el Grado de Maestro en Educación Infantil, Grado de Maestro en Primaria, Grado en Maestro en Primaria con Mención en Música. Su objetivo principal es interrelacionar las asignaturas Música y su aplicación Didáctica y Desarrollo de la Expresión Musical con las materias que forman parte de la Mención en Música. Todas ellas se coordinarán, a su vez, con otras asignaturas de la titulación que están invitadas a colaborar en el desarrollo del proyecto. Para el profesorado participante la puesta en marcha de este Proyecto significa un importante avance en la concepción cooperativa de la educación universitaria que interviene sobre un número elevado de alumnos. Para el alumnado que se vincule a este Proyecto significará una integración óptima de todos sus esfuerzos académicos, ya que el Proyecto nace, por una parte, de las necesidades planteadas por la Mención en Música y su organización curricular, puesto que quienes la escogen necesitan desarrollar en poco tiempo competencias y capacidades propias de un profesional solvente en el ámbito artístico-musical. Por otra parte, y a través de su participación, el profesorado en formación valorará la incorporación de la música como herramienta interdisciplinar útil para mejorar el aprendizaje de otras asignaturas; asimismo conocerá las posibilidades expresivas del lenguaje artístico como generador de espacios de convivencia, el otro eje medular del Proyecto. En definitiva, mediante un aprendizaje basado en la resolución de problemas, o con la participación en tareas colaborativas, el alumnado profundizará en los aprendizajes experimentales, desempeñando roles organizativos, cooperando entre sí y sobre todo optimizando el tiempo del que dispone para desarrollar los objetivos propuestos. Este Proyecto se concretará a partir de dos iniciativas: una artístico-musical y otra de características investigadoras. La primera propone la realización de obra/s que pueden englobar canto, danza, práctica instrumental y la segunda plantea la exposición del análisis de las actividades artísticas citadas y los procesos implicados en ellas. Ambas sugerencias se proyectarán hacia la comunidad educativa, lo que entrañará para el alumnado la vivencia y experimentación de iniciativas que lo formarán como gestor de proyectos y actividades, en relación directa con las competencias específicas de las titulaciones. Para la puesta en marcha y presentación del aspecto artístico de la innovación, se tendrán en cuenta aportaciones de autores como Karl Orff, Murray Schafer, Sinichi Suzuki, Silvia Malbrán, Ana Lucía Frega, entre otros. Para la sección del Proyecto centrado en la investigación, las metodologías serán las tradicionales, búsqueda y análisis de fuentes primarias y secundarias, trabajo de campo, elaboración de encuestas, anecdotarios y entrevistas

The O3N2 and N2 abundance indicators revisited: improved calibrations based on CALIFA and Te-based literature data

The use of IFS is since recently allowing to measure the emission line fluxes of an increasingly large number of star-forming galaxies both locally and at high redshift. The main goal of this study is to review the most widely used empirical oxygen calibrations, O3N2 and N2, by using new direct abundance measurements. We pay special attention to the expected uncertainty of these calibrations as a function of the index value or abundance derived and the presence of possible systematic offsets. This is possible thanks to the analysis of the most ambitious compilation of Te-based HII regions to date. This new dataset compiles the Te-based abundances of 603 HII regions extracted from the literature but also includes new measurements from the CALIFA survey. Besides providing new and improved empirical calibrations for the gas abundance, we also present here a comparison between our revisited calibrations with a total of 3423 additional CALIFA HII complexes with abundances derived using the ONS calibration by Pilyugin et al. (2010). The combined analysis of Te-based and ONS abundances allows us to derive their most accurate calibration to date for both the O3N2 and N2 single-ratio indicators, in terms of all statistical significance, quality and coverage of the space of parameters. In particular, we infer that these indicators show shallower abundance dependencies and statistically-significant offsets compared to those of Pettini and Pagel (2004), Nagao et al. (2006) and P\'erez-Montero and Contini (2009). The O3N2 and N2 indicators can be empirically applied to derive oxygen abundances calibrations from either direct abundance determinations with random errors of 0.18 and 0.16, respectively, or from indirect ones (but based on a large amount of data) reaching an average precision of 0.08 and 0.09 dex (random) and 0.02 and 0.08 dex (systematic; compared to the direct estimations),respectively.Comment: 12 pages, 5 figures, accepted for publication in A&