Machine learning techniques to select Be star candidates. An application in the OGLE-IV Gaia south ecliptic pole field

Statistical pattern recognition methods have provided competitive solutions for variable star classification at a relatively low computational cost. In order to perform supervised classification, a set of features is proposed and used to train an automatic classification system. Quantities related to the magnitude density of the light curves and their Fourier coefficients have been chosen as features in previous studies. However, some of these features are not robust to the presence of outliers and the calculation of Fourier coefficients is computationally expensive for large data sets. We propose and evaluate the performance of a new robust set of features using supervised classifiers in order to look for new Be star candidates in the OGLE-IV Gaia south ecliptic pole field. We calculated the proposed set of features on six types of variable stars and on a set of Be star candidates reported in the literature. We evaluated the performance of these features using classification trees and random forests along with K-nearest neighbours, support vector machines, and gradient boosted trees methods. We tuned the classifiers with a 10-fold cross-validation and grid search. We validated the performance of the best classifier on a set of OGLE-IV light curves and applied this to find new Be star candidates. The random forest classifier outperformed the others. By using the random forest classifier and colour criteria we found 50 Be star candidates in the direction of the Gaia south ecliptic pole field, four of which have infrared colours consistent with Herbig Ae/Be stars. Supervised methods are very useful in order to obtain preliminary samples of variable stars extracted from large databases. As usual, the stars classified as Be stars candidates must be checked for the colours and spectroscopic characteristics expected for them

On the Reduced SU(N) Gauge Theory in the Weyl-Wigner-Moyal Formalism

Weyl-Wigner-Moyal formalism is used to describe the large-$N$ limit of reduced SU$(N)$ quenching gauge theory. Moyal deformation of Schild-Eguchi action is obtained.Comment: 24 pages, phyzzx file, no figures, version to appear in Int. J. Mod. Phys.

Análisis demográficos de la población ovina segureña, como base para el desarrollo de su esquema de selección

La raza ovina Segureña originariamente procede de la cabecera del río Segura, distribuyéndose en la mayor parte de las estribaciones montañosas del Sudeste de España, donde confluyen las provincias de Almería, Granada, Jaén, Albacete y Región de Murcia. Su producción básica es la carne, obteniéndose corderos de elevada calidad con altos rendimientos en matadero. La leche se destina exclusivamente a la cría de la descendencia y la producción de lana es completamente marginal. Según la Orden Ministerial de fecha 12-09-1985 se aprueba definitivamente la reglamentación específica del libro genealógico y de comprobación de rendimientos de la raza Segureña. En la actualidad los censos de la raza superan la cifra de 1.300.000 ovejas de las cuales algo más de 120.000 ejemplares, es decir, en torno al 9,6% del total de la población, se encuentran inscritos en el libro genealógico de la raza. A día de hoy el esquema de selección de la raza ovina Segureña se encuentra a pleno rendimiento y por ello se hace necesario conocer la estructura poblacional de la misma, a la hora de tomar decisiones de interés. En el presente trabajo se describen los tamaños efectivos de la población incluida en la asociación de criadores. Del mismo modo se establece la pirámide de edades total y por núcleos, como paso previo para el cálculo de sus intervalos generacionales. Por supuesto se incluyen los censos totales y parciales por localización y por sexo para una mejor descripción de la población

Spontaneous Symmetry Breakdown in non-relativistic Quantum Mechanics

The advantages and disadvantages of some pedagogical non-relativistic quantum-mechanical models, used to illustrate spontaneous symmetry breakdown, are discussed. A simple quantum-mechanical toy model (a spinor on the line, subject to a magnetostatic interaction) is presented, that exhibits the spontaneous breakdown of an internal symmetry.Comment: 19 pages, 5 figures. arXiv admin note: substantial text overlap with arXiv:1111.1213. Equations (30) and (31) have been corrected. Other minor correction

Detection of metabolites in Flor de Mayo common beans (Phaseolus vulgaris L.) and their response to inoculation with Trichoderma harzianum

Seed germination involves complex processes where plant growth-promoting substances are released into the growth medium, mainly involving pathways that start in tryptophan (TRP) and end in the formation of indole-3-acetic acid (IAA). Among them, four are known as TRP-dependent and a fifth as TRP-independent. Some compounds were observed during germination of bean seeds that involved at least three IAA synthesis pathways and that kynurenine (KYN) is the first detected metabolite which is found in greater concentration. It was followed by tryptamine (TAM), TRP and IAA. The results of Trichoderma harzianum inoculation in greenhouse tests showed variability in Flor de Mayo beans seedlings in response to physiological level and production parameters. The effect of Trichoderma in Flor de Mayo common bean showed that strain 802 had a significant effect on the development of the height of bean seedlings, and that the 812 strain showed significant effect on the development of root bean seedlings. Increased growth of stem and root caused by Trichoderma strains in Flor de Mayo beans involves beneficial effects of inoculation on plant growth and development parameters and can be taken as they were a measure of survival and development of seedlings.Key words: Biofertilizers, indole-3-acetamide, tryptophan,indole-3- acetic acid, kynurenine

Estrategias de afrontamiento y bienestar psicológico en jóvenes tenistas de competición

The study aimed to examine the types of coping strategies preferred by adolescent competition tennis players and specific attention was paid to understanding these strategies' perceived effectiveness and the coping strategy's subsequent effects on well-being. The sample for the study was made up of 27 adolescent tennis players with a mean age of 15 years who participate at a high competitive level. The Approach to Coping in Sport Questionnaire (ACSQ-1) was used to measure the coping strategy used by the players and their psychological well-being was assessed by the Psychological Well-Being Scale. The results indicated that the emotional calming strategy was the tennis players' preferred coping strategy in general. At the same time, emotional calming and active planning were the strategies the players' considered to be the most effective in terms of improving performance. An additional finding was that players with lower levels of self-acceptance relied more heavily on the emotional calming strategy and those with higher levels of self-acceptance used mental distancing more frequently. Players who perceived greater environmental control relied more heavily upon mental distancing as their preferred coping strategy. These findings indicate that individual differences were present in terms of preferred coping strategies and that the strategies produced differentiated effects on well-being for young competition tennis players

Brain iron deficiency changes the stoichiometry of adenosine receptor subtypes in cortico-striatal terminals. Implications for restless legs syndrome

Brain iron deficiency (BID) constitutes a primary pathophysiological mechanism in restless legs syndrome (RLS). BID in rodents has been widely used as an animal model of RLS, since it recapitulates key neurochemical changes reported in RLS patients and shows an RLS-like behavioral phenotype. Previous studies with the BID-rodent model of RLS demonstrated increased sensitivity of cortical pyramidal cells to release glutamate from their striatal nerve terminals driving striatal circuits, a correlative finding of the cortical motor hyperexcitability of RLS patients. It was also found that BID in rodents leads to changes in the adenosinergic system, a downregulation of the inhibitory adenosine A1 receptors (A1Rs) and upregulation of the excitatory adenosine A2A receptors (A2ARs). It was then hypothesized, but not proven, that the BID-induced increased sensitivity of cortico-striatal glutamatergic terminals could be induced by a change in A1R/A2AR stoichiometry in favor of A2ARs. Here, we used a newly developed FACS-based synaptometric analysis to compare the relative abundance on A1Rs and A2ARs in cortico-striatal and thalamo-striatal glutamatergic terminals (labeled with vesicular glutamate transporters VGLUT1 and VGLUT2, respectively) of control and BID rats. It could be demonstrated that BID (determined by measuring transferrin receptor density in the brain) is associated with a selective decrease in the A1R/A2AR ratio in VGLUT1 positive-striatal terminals