A multi-domain approach to asteroid families identification

Previous works have identified families halos by an analysis in proper elements domains, or by using Sloan Digital Sky Survey-Moving Object Catalog data, fourth release (SDSS-MOC4) multi-band photometry to infer the asteroid taxonomy, or by a combination of the two methods. The limited number of asteroids for which geometric albedo was known until recently discouraged in the past the extensive use of this additional parameter, which is however of great importance in identifying an asteroid taxonomy. The new availability of geometric albedo data from the Wide-field Infrared Survey Explorer (WISE) mission for about 100,000 asteroids significantly increased the sample of objects for which such information, with some errors, is now known. In this work we proposed a new method to identify families halos in a multi-domain space composed by proper elements, SDSS-MOC4 (a*,i-z) colors, and WISE geometric albedo for the whole main belt (and the Hungaria and Cybele orbital regions). Assuming that most families were created by the breakup of an undifferentiated parent body, they are expected to be homogeneous in colors and albedo. The new method is quite effective in determining objects belonging to a family halo, with low percentages of likely interlopers, and results that are quite consistent in term of taxonomy and geometric albedo of the halo members.Comment: 23 pages, 18 figures, 6 tables. Accepted for publication in MNRA

Growth and isoenzyme comparison of five isolates of Venturia inaequalis

Nous avons observé l'aspect du mycélium de cinq isolats du Venturia inaequalis. Des différences ont été constatées entre les différents isolats des races et l'isolât de la race 3 se distingue le plus des autres. Quinze systèmes enzymatiques et les protéines non-spécifiques ont été testés par électrophorèse sur gel de polyacrylamide ou d'amidon. Treize des systèmes enzymatiques ainsi que les protéines non-spécifiques révélées ne montraient pas de variation entre les isolats des races. Le patron isoenzymatique des esterases permet de séparer ces isolats car une seule isoenzyme est commune à tous et deux autres ne se retrouvent que chez les isolats des races 1 et 5. Une isoenzyme de F anhydrase carbonique est spécifique à l'isolât de la race 2.Observation of the mycelial aspect of five isolates representing the fîve races of Venturia inaequalis indicates that it is possible to differentiate these isolates by their growth pattern and the isolate of race 3 appears to be the most easily distinguishable. Fifteen enzyme systems and non-specific proteins have been analyzed by polyacrylamide and starch gel electrophoresis. Thirteen of the isoenzymes systems and non-specific proteins showed no variation among the five isolates. Esterases isoenzyme patterns allow separation of the isolates since only one isoenzyme is common to all isolates and two others are shared by isolates of race 1 and 5. One carbonic anhydrase isoenzyme was observed to be specific to the isolate of race 2

El relato digital (digital storytelling) como elemento narrativo en el ámbito educativo

El relato es una de las formas más antiguas de transferencia de conocimiento y una capacidad del ser humano que la psicología considera una forma de pensamiento. Si bien la escuela formal no se declina por usar el relato como un vehículo de transferencia de conocimiento, éste es una herramienta útil de enseñanza que permite a los alumnos utilizar sus habilidades y conocimientos, ya que siempre que se cuenta una historia, el oyente explora nuevos mundos y escenarios, al tiempo que desarrolla habilidades de pensamiento crítico para conectarlos a su propio mundo y experiencias. El Relato Digital es una expresión moderna del antiguo arte de contar historias que toma su estructura y elementos del relato tradicional, y que, al incluir la tecnología multimedia, ha aumentado su dimensión pragmática en la educación. Es un arte que permite a los alumnos disfrutar del montaje de un producto multimedia para compartir una historia. Al hacer uso de las nuevas tecnologías que facilitan la conexión, comunicación y colaboración con otras personas en todo el mundo, el Relato Digital permite establecer un puente entre la educación y la tecnología, válido en cualquier tema de estudio y se perfila como una herramienta efectiva para el desarrollo de las Competencias del Siglo XXI.Storytelling is one of the most ancient forms of knowledge transfer and a human capacity considered by psychology as a form of thinking. While formal school doesn’t opt to use storytelling as a vehicle to transfer knowledge, this is a useful teaching tool that allows students to use their skills and knowledge, and that whenever a story is told, the listener explores new worlds and scenarios, while developing critical thinking skills to connect them to its own world and experiences. Digital Storytelling is a modern expression of the ancient art of storytelling that takes its structure and elements of the traditional tale, and that by including multimedia technology, has increased its pragmatic dimension in education. It is an art that allows students to enjoy a multimedia product assembly to share a story. By making use of new technologies that facilitate networking, communication and collaboration with others worldwide, Digital Storytelling allows to establish a bridge between education and technology, valid on any topic and is emerging as an effective tool for the development of the 21st Century skills

Chemical abundances and kinematics of barium stars

In this paper we present an homogeneous analysis of photospheric abundances based on high-resolution spectroscopy of a sample of 182 barium stars and candidates. We determined atmospheric parameters, spectroscopic distances, stellar masses, ages, luminosities and scale height, radial velocities, abundances of the Na, Al, $alpha$-elements, iron-peak elements, and s-process elements Y, Zr, La, Ce, and Nd. We employed the local-thermodynamic-equilibrium model atmospheres of Kurucz and the spectral analysis code {\sc moog}. We found that the metallicities, the temperatures and the surface gravities for barium stars can not be represented by a single gaussian distribution. The abundances of $alpha$-elements and iron peak elements are similar to those of field giants with the same metallicity. Sodium presents some degree of enrichment in more evolved stars that could be attributed to the NeNa cycle. As expected, the barium stars show overabundance of the elements created by the s-process. By measuring the mean heavy-element abundance pattern as given by the ratio [s/Fe], we found that the barium stars present several degrees of enrichment. We also obtained the [hs/ls] ratio by measuring the photospheric abundances of the Ba-peak and the Zr-peak elements. Our results indicated that the [s/Fe] and the [hs/ls] ratios are strongly anti-correlated with the metallicity. Our kinematical analysis showed that 90% of the barium stars belong to the thin disk population. Based on their luminosities, none of the barium stars are luminous enough to be an AGB star, nor to become self-enriched in the s-process elements. Finally, we determined that the barium stars also follow an age-metallicity relation.Comment: 30 pages, 26 figures, 18 tables, accepted for publication in MNRA

Phoenix sylvestris (L.) Roxburg (Arecaceae) in Argentina

Se da a conocer la presencia de Phoenix sylvestris (L.) Roxburg, cultivada como ornamental y naturalizada en ambientes antropizados de Mendoza, San Juan y otras provincias de Argentina. Se cree que fue introducida al país hace aproximadamente 100 años y se la cita por primera vez para la flora argentina. Se hibrida con Ph. canariensis Hort. ex Chabaud, también cultivada y naturalizada, lo que en ocasiones dificulta su determinaciónPhoenix sylvestris (L.) Roxburg, cultivated as ornamental and naturalized in anthropic environments of Mendoza, San Juan, and other provinces of Argentina, is presented herein. We think that this species was introduced nearly 100 years ago, and is cited for the first time for Argentina. Ph. sylvestris hybridizes with Ph. canariensis, cultivated too, which on many occasions makes its determination difficult.Fil: Roig Junent, Fidel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Martinez Carretero, Eduardo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Osorio, E. Martín. Universidad de La Laguna; Españ

A lower bound for the number of components of the moduli schemes of stable rank 2 vector bundles on projective 3-folds

Fix a smooth projective 3-fold X, c1, H ∈ Pic(X) with H ample, and d ∈ Z. Assume the existence of integers a, b with a ≠ 0 such that ac1 is numerically equivalent to bH. Let M(X, 2, c1, d, H) be the moduli scheme of H-stable rank 2 vector bundles, E, on X with c1(E) = c1 and c2(E) · H = d. Let m(X, 2, c1, d, H) be the number of its irreducible components. Then lim supd→ ∞m(X, 2, c1, d, H) = +∞

Constraining the Hadronic Contributions to the Muon Anomalous Magnetic Moment

The mini-proceedings of the Workshop on "Constraining the hadronic contributions to the muon anomalous magnetic moment" which included the "13th meeting of the Radio MonteCarLow WG" and the "Satellite meeting R-Measurements at BES-III" held in Trento from April 10th to 12th, 2013, are presented. This collaboration meeting aims to bring together the experimental e+e- collider communities from BaBar, Belle, BESIII, CMD2, KLOE, and SND, with theorists working in the fields of meson transitions form factors, hadronic contributions to (g-2)_\mu and effective fine structure constant, and development of Monte Carlo generator and Radiative Corrections for precision e+e- and tau physics.Comment: 45 pages, 17 contributions. Editors: P. Masjuan and G. Venanzon