El papel de la matemática en el proceso educativo inicial

A short analysis of the educational values of Mathematics and of the main defects that can be observed in the current trends in Spanish primary and secondary schools, together with some remedial suggestions

Molecular Diagnostics in the Mycosphaerella Leaf Spot Disease Complex of Banana and for Radopholus similis

Mycosphaerella leaf spots and nematodes threaten banana cultivation worldwide. The Mycosphaerella disease complex involves three related ascomycetous fungi: Mycosphaerella fijiensis, M. musicola and M. eumusae. The exact distribution of these three species and their disease epidemiology remain unclear, since their symptoms and life cycles are rather similar. Diagnosing these diseases and the respective causal agents is based on the presence of host symptoms and fungal fruiting structures, but is time consuming and not conducive to preventive management. In the present study, we developed rapid and robust species-specific diagnostic tools to detect and quantify M. fijiensis, M. musicola and M. eumusae. Conventional species-specific PCR primers were developed based on the actin gene that detected as little as 100, 1 and 10 pg/µl DNA from, respectively, M. fijiensis, M. musicola and M. eumusae. Furthermore, TaqMan real-time quantitative PCR assays that were developed based on the ß-tubulin gene detected quantities as low as 1 pg/µl DNA of each species from pure cultures and 1.6 pg/µl DNA/mg of M. fijiensis from dry leaf tissue. The efficacy of the tests was validated using naturally infected banana leaves. Similar technology has been used to develop a quantitative PCR assay for the banana burrowing nematode, Radopholus similis, which is currently being validate

Time-dependent Mechanics and Lagrangian submanifolds of Dirac manifolds

A description of time-dependent Mechanics in terms of Lagrangian submanifolds of Dirac manifolds (in particular, presymplectic and Poisson manifolds) is presented. Two new Tulczyjew triples are discussed. The first one is adapted to the restricted Hamiltonian formalism and the second one is adapted to the extended Hamiltonian formalism

Participatory Action Research experiences in Andalusia. Linking science and day-to-day life. Role of public policies

Andalucia holds 54% of the certified organic Spanish area, and 30% of the total amount of operators (MAGRAMA, 2013). From 2004 up to 2007, the regional government implemented, through the Organic Action Plans (Plan Andaluz de Agricultura Ecológica) specific public policies for research and knowledge transfer based on Participatory Action Research methodology (CAP, 2007). This article aims to focus on this methodology potential as a means to enhance stakeholders and civil society participation and engagement in the knowledge transfer activities

Reply to "Comment on 'Scalar-tensor gravity coupled to a global monopole and flat rotation curves' "

In Brans-Dicke theory of gravity we explain how the extra constant value in the formula for rotation velocities of stars in a galactic halo can be obtained due to the global monopole field. We argue on a few points of the preceding Comment and discuss improvement of our model.Comment: 4 pages, RevTeX4 fil

Un modelo para predecir el crecimiento de Eucalyptus globulus procedente de semilla en Bolivia

Eucalyptus globulus is one of the most planted species in the Inter-Andean Valleys of Bolivia, where growing conditions are different from most places where eucalypts have been studied. This prevents a straightforward utilization of models fitted elsewhere. In this study a distance-independent individual-tree growth model for E. globulus plantations in Bolivia was developed based on data from 67 permanent sample plots. The model consists of sub-models for dominant height, tree diameter increment, height-diameter relationship and survival. According to model-based simulations, the mean annual increment with the optimal rotation length is about 13 m3 ha–1 yr–1 on medium-quality sites and 18 m3 ha–1 yr–1on the best sites. A suitable rotation length for maximizing wood production is approximately 30 years on medium sites and 20 years on the most productive sites. The developed models provide valuable information for further studies on optimizing the management and evaluating alternative management regimes for the species.Eucalyptus globulus es una de la especies más plantadas en los Valles Inter-Andinos de Bolivia, donde las condiciones ecológicas difieren de la mayor parte de zonas en que esta especie ha sido objeto de estudio. Por este motivo, no es aconsejable la aplicación directa de los modelos desarrollados para otras zonas. En este estudio se desarrolló un modelo de crecimiento de árbol individual independiente de la distancia para E. globulus en Bolivia a partir de los datos medidos en 67 parcelas permanentes. El modelo está formado por los siguientes submodelos: altura dominante, incremento en diámetro, relación altura-diámetro y supervivencia. Las simulaciones basadas en las ecuaciones del modelo arrojaron crecimientos medios anuales de 13 m3 ha–1 año–1 en sitios de calidad media y de 18 m3 ha–1 año–1 en los sitios de mayor calidad. La máxima renta en especie se alcanza a los 30 años en sitios de calidad media y a los 20 años en los mejores sitios. Los modelos desarrollados aportan información valiosa para futuros estudios de optimización de la gestión y de evaluación de alternativas de manejo para esta especie

Scalar Field as Dark Matter in the Universe

We investigate the hypothesis that the scalar field is the dark matter and the dark energy in the Cosmos, wich comprises about 95% of the matter of the Universe. We show that this hypothesis explains quite well the recent observations on type Ia supernovae.Comment: 4 pages REVTeX, 1 eps figure. Minor changes. To appear in Classical and Quantum Gravit

Escribir al padre en la adolescencia tardía: comparación entre italia y méxico

El presente trabajo tuvo como objetivo explorar y analizar mediante estrategias cualitativas y cuantitativas, el contenido y la modalidad narrativa con la cual una muestra de adolescentes tardíos se dirige a su padre. Participaron 202 sujetos (X=19.4 años de edad; DS= .98).), inscritos a tres diferentes carreras (Psicología, Medico Cirujano y Biología) de la UNAM, FES Iztacala. Los datos fueron analizados con el programa ALCESTE, el cual produjo cuatro mundos lexicales, en los cuales no se encontraron referencias a las funciones normativas paternales

Microsatellites to enhance characterization, conservation and breeding value of Capsicum germplasm

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