Circumstellar effects on the Rb abundances in O-rich AGB stars

For the first time we explore the circumstellar effects on the Rb (and Zr) abundance determination in O-rich asymptotic giant branch (AGB) stars by considering the presence of a gaseous circumstellar envelope with a radial wind. A modified version of the spectral synthesis code Turbospectrum was used to deal with extended atmosphere models and velocity fields. The Rb and Zr abundances were determined from the resonant 7800A Rb I line and the 6474A ZrO bandhead, respectively, in five representative O-rich AGB stars with different expansion velocity and metallicity. By using our new dynamical models, the Rb I line profile (photospheric and circumstellar components) is very well reproduced. Interestingly, the derived Rb abundances are much lower (by 1-2 dex) in those O-rich AGB stars showing the higher circumstellar expansion velocities. The Zr abundances, however, remain close to the solar values. The Rb abundances and Rb/Zr ratios derived here significantly alleviate the problem of the present mismatch between the observations of intermediate-mass (4-8 solar masses) Rb-rich AGB stars and the AGB nucleosynthesis theoretical predictions.Comment: Accepted for publication in Astronomy & Astrophysics Letters (7 pages, 5 figures, and 2 tables); final version (language corrected

Medical Malpractice and Health Maintenance Organizations: Evolving Theories and ERISA\u27s Impact

Employers are now turning in increasing numbers to Health Maintenance Organizations ( HMO ) and Preferred Provider Organizations ( PPO ) to deliver health insurance benefits to their employees

Softly Broken N=2 QCD with Massive Quark Hypermultiplets, I

We present a general analysis of all the possible soft breakings of N=2 supersymmetric QCD, preserving the analytic properties of the Seiberg-Witten solutions for the SU(2) group with Nf=1, 2, 3 hypermultiplets. We obtain all the couplings of the spurion fields in terms of properties of the Seiberg-Witten periods, which we express in terms of elementary elliptic functions by uniformizing the elliptic curves associated to each number of flavors. We analyze in detail the monodromy properties of the softly broken theory, and obtain them by a particular embedding into a pure gauge theory with higher rank group. This allows to write explicit expressions of the effective potential, which are close to the exact answer for moderate values of the supersymmetry breaking parameters. The vacuum structures and phases of the broken theories will be analyzed in the forthcoming second part of this paper.Comment: 35 pages, 3 figures, LaTeX file. Minor corrections in a few formulae, typos correcte

Los videojuegos, nuevas narrativas del siglo XXI.

85 p. Recuso Electr?nicoNuestro trabajo realiza una contextualizaci?n, acerca de los conceptos b?sicos del juego a trav?s de los planteamientos de Huizinga, que cimentaron la base para toda una serie de estudios referentes a los beneficios de la l?dica y el juego en el desarrollo cognitivo y emocional. De igual manera analizaremos el concepto de videojuego como tal y los beneficios descubiertos acerca de estos, haciendo una revisi?n de diferentes estudios dentro de los cuales encontramos los del Psic?logo Carlos Gonz?lez Tard?n, entre varios autores m?s. En el segundo cap?tulo, se desarrollar? un an?lisis narratol?gico a diferentes videojuegos, tomando como base los estudios realizados por Mart?nez y Scheffel en cuanto estudios narratol?gicos literarios y tambi?n las postulaciones de Gaudreault y Jost quienes desarrollaron todo un an?lisis narratol?gico al discurso cinematogr?fico. Posteriormente realizaremos en nuestro tercer cap?tulo una investigaci?n acerca del proceso creativo involucrado en la realizaci?n de argumentos y guiones dise?ados para los videojuegos,. Dentro de dicho proceso se analiz? la relaci?n de los fundamentos b?sicos de la producci?n narrativa, establecidos por Arist?teles, Vladimir Propp, Joseph Campbell y Lajos Egri, adem?s de su aplicaci?n en el campo de los videojuegos, de igual manera a trav?s de varios ejemplos se se plasma nuestra experiencia en la realizaci?n de los distintos formatos de guiones utilizados en la composici?n de nuestro propio videojuego. Finalizamos con algunas conclusiones referentes al tema, en la que a trav?s del resumen de los diferentes an?lisis y nuestra experiencia.Our work makes a contextualization about the basics of the game through approaches Huizinga, which cemented the basis for a series of studies on the benefits of fun and play in cognitive and emotional development. Similarly we discuss the concept of game as such and benefits discovered about these, by reviewing different studies within which are those of Psic?logo Tard?n Carlos Gonzalez, among several other authors. In the second chapter, different games narratological analysis, based on studies by Martinez and Scheffel as narratological literary studies and applications from Gaudreault and Jost who developed a whole narratological the cinematic discourse analysis will be developed. Then we will make our third chapter an investigation into the creative process involved in making arguments and scripts designed for video games ,. Within this process the relationship of the basic fundamentals of narrative production was analyzed, established by Aristotle, Vladimir Propp, Joseph Campbell and Lajos Egri, in addition to its application in the field of video games, equally through several examples our experience is reflected in the performance of various script formats used in the composition of our own game. We conclude with some conclusions concerning the topic, which through the summary of the different analyzes and our experience. Keywords: Narratolog?a, Video Games, Story, Education

Rubidium and zirconium abundances in massive Galactic asymptotic giant branch stars revisited

Luminous Galactic OH/IR stars have been identified as massive (>4-5 M_s) AGB stars experiencing HBB and Li production. Their Rb abundances and [Rb/Zr] ratios derived from hydrostatic model atmospheres, are significantly higher than predictions from AGB nucleosynthesis models, posing a problem to our understanding of AGB evolution and nucleosynthesis. We report new Rb and Zr abundances in the full sample of massive Galactic AGB stars, previously studied with hydrostatic models, by using more realistic extended model atmospheres. We use a modified version of the spectral synthesis code Turbospectrum and consider the presence of a circumstellar envelope and radial wind. The Rb and Zr abundances are determined from the 7800 A Rb I resonant line and the 6474 A ZrO bandhead, respectively, and we explore the sensitivity of the derived abundances to variations of the stellar (Teff) and wind (M_loss, beta and vexp) parameters in the extended models. The Rb and Zr abundances derived from the best spectral fits are compared with the most recent AGB nucleosynthesis theoretical models. The new Rb abundances are much lower (even 1-2 dex) than those derived with the hydrostatic models, while the Zr abundances are similar. The Rb I line profile and Rb abundance are very sensitive to the M_loss rate but much less sensitive to variations of the wind velocity-law and the vexp(OH). We confirm the earlier preliminary results based on a smaller sample of massive O-rich AGB stars, that the use of extended atmosphere models can solve the discrepancy between the AGB nucleosynthesis theoretical models and the observations of Galactic massive AGB stars. The Rb abundances, however, are still strongly dependent of the M_loss, which is unknown in these AGB stars. Accurate M_loss rates in these massive Galactic AGB stars are needed in order to break the models degeneracy and get reliable Rb abundances in these stars.Comment: Accepted for publication in A&A, 14 pages, 12 figures, 4 table

The house museum environment: A methodology for evaluation of hygrothermal conditions

In recent decades, the obvious deterioration suffered by the collections exhibited in museum rooms has become alarming. The lack of environmental control is currently one of the most vulnerable points in the exhibition of objects and works of art in museums.In historic cities, museums are usually housed in old buildings or museum-houses that were not created specifically for the preservation of heritage objects. In this case, preventive conservation includes both the collections and the building itself. The possibilities of creating stable microclimates for the conservation of objects on display are reduced when it is not possible to change its architectural characteristics either due to lack of resources or because it is a priority to conserve the building envelope.The literature indicates that within the criteria of preventive conservation, the monitoring and control of environmental conditions are essential practices to minimize damage to the heritage during the exhibition.The purpose of this work is to present a methodology to evaluate the degree of adequacy of environmental conditions to the exposed heritage in museum-houses through the measurement and analysis of the microclimatic parameters (temperature and relative humidity). The procedure consisted in measuring the temperature and relative humidity conditions of a given space and correlating them with the appropriate conditions according to the material composition of the object, both in average levels and fluctuations. For them, two experimental studies were carried out in three representative rooms belonging to the Historic House of Independence Museum in Tucuman (Phot. 1), Argentina, which is built with two types of materials (brick and adobe). The first, analyzes the evolution of the parameters of temperature and relative humidity in recent years inside a museum-house (2010-2014) and the second, evaluates the degree of adaptation of the heritage exposed to the temperature and relative humidity conditions in specifics works of art (February to May of 2013). The approach is based on a short, medium and long-term field monitoring of the environmental parameters and the measured data are elaborated in terms of average monthly and daily values and mean daily fluctuation. The analysis of the microclimatic data has been carried out according to the Standard ASHRAE for historical buildings and a Performance Index PI for temperature and relative humidity parameters has calculated and related to the potential damage of the works of art exhibited. The results of the analysis of study 1 show that this house is affected significantly by the influence of the climatic conditions, especially during the hottest months of the year. The statistical analysis did not show significant changes in the behavior of the parameters in relation to the characteristics of both types of materials that were used in the building of the museum, which may be related to the location of each room and the opening or not of windows to the exterior. The results of study 2 indicate that the heritage exhibited in the selected rooms is exhibited in inadequate thermo hygrometric conditions, effects that could become visible over time if the conditions are not reversed. During the period analyzed in 2013, only 10% of the time the average levels remained within the levels established by ASHRAE B (Fig. 1). Some daily fluctuations of short periods of RH above the limit allowed of 10% were detected through more quickly by means of an extension of the performance index PI that defines the percentage of time during which the daily fluctuations of temperature and relative humidity were kept inside safe limits.The analysis of the indoor environment through the proposed methodology permits the assessment of the environmental quality in contact with the exposed heritage and the planning of actions aimed at improving the conservation of heritage according to the potentialities of the building. The evaluation of actual levels of variation of the thermo hygrometric variables also determines the most critical variable, which requires constant vigilance of the staff in charge of the collections and the evaluation of success of the applied actions. In the case analyzed, for example, is necessary to implement improvements to control the temperature and humidity levels to bring the PI = 10% index to a percentage of at least 30 or 40%.The application of this methodology together with the collaboration of museum curators will allow the detection of the causes of damage without having to implement the high cost of energetic systems as an alternative solution. The thermo hygrometric behavior observed in this house-museum is typical of the museums in the region and, therefore, the procedure explained could extend to other cases with the purpose of implementing real solutions for a sustainable preventive conservation of heritage.Fil: Zamora, María Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; ArgentinaFil: O´donell, Beatriz Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Luminotecnia, Luz y Visión; Argentin

Clear evidence for the presence of second-generation asymptotic giant branch stars in metal-poor Galactic globular clusters

Galactic globular clusters (GCs) are known to host multiple stellar populations: a first generation with a chemical pattern typical of halo field stars and a second generation (SG) enriched in Na and Al and depleted in O and Mg. Both stellar generations are found at different evolutionary stages (e.g., the main-sequence turnoff, the subgiant branch, and the red giant branch). The non detection of SG asymptotic giant branch (AGB) stars in several metal-poor ([Fe/H] < -1) GCs suggests that not all SG stars ascend the AGB phase, and that failed AGB stars may be very common in metal-poor GCs. This observation represents a serious problem for stellar evolution and GC formation/evolution theories. We report fourteen SG-AGB stars in four metal-poor GCs (M 13, M 5, M 3, and M 2) with different observational properties: horizontal branch (HB) morphology, metallicity, and age. By combining the H-band Al abundances obtained by the APOGEE survey with ground-based optical photometry, we identify SG Al-rich AGB stars in these four GCs and show that Al-rich RGB/AGB GC stars should be Na-rich. Our observations provide strong support for present, standard stellar models, i.e., without including a strong mass-loss efficiency, for low-mass HB stars. In fact, current empirical evidence is in agreement with the predicted distribution of FG and and SG stars during the He-burning stages based on these standard stellar models.Comment: Accepted for publication in The Astrophysical Journal Letters (16 pages, 4 figures, and 1 table

Analysis and forecast of performance characteristics of combine harvesters

ArticleThis article presents results of an experimental research of qualitative indicators of the modern combine harvesters (Case IH Axil Flow 8230, MasseyFergusonMFT7, JohnDeereS680i, ClaasLexion760, NewHolland CR9.80) used for winter wheat harvesting. Based on the results obtained, determination was made regarding the productivity of combine harvesters on the field, fuel consumption, and field conditions influence the grain loss and grain damage caused by a harvester. When conducting the experimental research of a combine's performance on the field a study of the effectiveness of the combine JohnDeereS680i was made on different modes. A program 'Machine Unit', designed by the authors, was used for the determination of productivity, fuel consumption and quality indicator for harvesting