¿Es importante la educación física? su valoración según la edad del alumno y el tipo de centro

En nuestro estudio se analiza la influencia de la edad del alumno y el tipo de centro sobre diversos aspectos relacionados con la Educación Física: organización, profesorado que lo imparte, dificultad, utilidad, preferencia por las actividades físico-deportivas, etc. Para ello, hemos utilizado un Cuestionario de Actitudes hacia la Educación Física (C. A. E. F.) de Moreno y cols. (1996a) aplicándolo a una muestra de estudiantes de primer y segundo Ciclo de Enseñanza Secundaria Obligatoria. Para el análisis de resultados hemos realizado análisis de varianza y cuando teníamos más de dos grupos la prueba F-test de Scheffe para comparar grupo a grupo a posteriori. Entre las principales conclusiones destacamos que los alumnos que acuden a centros públicos valoran más la asignatura y el profesor, prefieren la Educación Física y el deporte frente a otro tipo de actividades, perciben la asignatura más difícil, hacen una valoración más positiva de las clases de Educación Física frente al alumnado de los centros privados; en general existe una mayor empatía con el profesor y la asignatura. En los centros privados-concertados resultan mejor valoradas las rutinas de ducha/cambio de indumentaria en las clases. Igualmente en los centros privados-concertados son más valorados los aspectos competitivos de las actividades físicas. Los alumnos más pequeños (11-12 años), en comparación con los mayores (13 y 14-15 años) hacen una mejor valoración de la asignatura y el profesor, consideran que aprobar en Educación Física es más fácil que en otras asignaturas, a su vez la consideran más útil para su futuro, existe una mayor empatía hacia el profesor, consideran importante en el profesor, el hecho de que utilice la indumentaria adecuada; sin embargo son los que peor aceptan el cambio de ropa una vez finalizada la clase

On small black holes, KK monopoles and solitonic 5-branes

We review and extend results on higher-curvature corrections to different configurations describing a superposition of heterotic strings, KK monopoles, solitonic 5-branes and momentum waves. Depending on which sources are present, the low-energy fields describe a black hole, a soliton or a naked singularity. We show that this property is unaltered when perturbative higher-curvature corrections are included, provided the sources are fixed. On the other hand, this character may be changed by appropriate introduction (or removal) of sources regardless of the presence of curvature corrections, which constitutes a non-perturbative modification of the departing system. The general system of multicenter KK monopoles and their 5-brane charge induced by higher-curvature corrections is discussed in some detail, with special attention paid to the possibility of merging monopoles. Our results are particularly relevant for small black holes (Dabholkar-Harvey states, DH), which remain singular after quadratic curvature corrections are taken into account. When there are four non-compact dimensions, we notice the existence of a black hole with regular horizon whose entropy coincides with that of the DH states, but the charges and supersymmetry preserved by both configurations are different. A similar construction with five non-compact dimensions is possible, in this case with the same charges as DH, although it fails to reproduce the DH entropy and supersymmetry. No such configuration exists if $d>5$, which we interpret as reflecting the necessity of having a 5-brane wrapping the compact space

A Corpus-Based, Pilot Study of Lexical Stress Variation in American English

Phonological free variation describes the phenomenon of there being more than one pronunciation for a word without any change in meaning (e.g. because, schedule, vehicle). The term also applies to words that exhibit different stress patterns (e.g. academic, resources, comparable) with no change in meaning or grammatical category. A corpus-based analysis of free variation is a useful tool for testing the validity of surveys of speakers' pronunciation preferences for certain variants. The current paper presents the results of a corpus-based pilot study of American English, in an attempt to replicate Mompéan's 2009 study of British English

Supervised and unsupervised data mining approaches in loan default prediction

Given the paramount importance of data mining in organizations and the possible contribution of a data-driven customer classification recommender systems for loan-extending financial institutions, the study applied supervised and supervised data mining approaches to derive the best classifier of loan default. A total of 900 instances with determined attributes and class labels were used for the training and cross-validation processes while prediction used 100 new instances without class labels. In the training phase, J48 with confidence factor of 50% attained the highest classification accuracy (76.85%), k-nearest neighbors (k-NN) 3 the highest (78.38%) in IBk variants, naïve Bayes has a classification accuracy of 76.65%, and logistic has 77.31% classification accuracy. k-NN 3 and logistic have the highest classification accuracy, F-measures, and kappa statistics. Implementation of these algorithms to the test set yielded 48 non-defaulters and 52 defaulters for k -NN 3 while 44 non-defaulters and 56 defaulters under logistic. Implications were discussed in the paper

Variáveis de decisão de compra de produtos industriais em Cali e Yumbo

This paper is the result of a research project for which purchasing managers at small, medium, and large-size manufacturing companies in Cali and Yumbo were surveyed and interviewed to identify variables that have an impact on the decision to purchase industrial goods and services such as raw materials, hardware, and spare parts, as well as machinery maintenance and repair services. This information was used to identify the level of significance given by purchasers to the following factors when making a purchasing decision: proximity, supplier’s level of technological development, price, delivery terms, product quality, warranty, quality certification, performance and punctuality, credit, confidentiality, reliability, personalized service, technical support, service outside office hours, on weekends and holidays, after-sales service, supplier’s own fleet, degree of friendship with suppliers, training on the part of suppliers, product origin (whether local or imported), supplier’s ethical practices, supplier company’s size, sales representative’s training level, and frequency of sales calls.El artículo es resultado de una investigación para la cual se encuestaron y entrevistaron a los jefes de compras de las pequeñas, medianas y grandes empresas industriales de Cali y Yumbo con el objetivo de identificar las variables que inciden en la decisión de compra de productos industriales, como: materias primas, productos de ferretería, repuestos, el mantenimiento y la reparación de maquinaria. Se identificó el nivel de importancia que dá el comprador al momento de tomar su decisión de compra a la cercanía, el grado de desarrollo tecnológico del proveedor, el precio, tiempo de entrega, calidad del producto, garantía, certificación de calidad, cumplimiento y puntualidad, crédito, confidencialidad, confiabilidad, atención personalizada, asesoría técnica, atención por fuera de horarios de oficina y fines de semana-festivos, servicio postventa, transporte propio, grado de amistad con el vendedor, capacitación por parte del proveedor, origen del producto (nacional o importado), prácticas éticas por parte del proveedor, tamaño del proveedor, nivel de capacitación del asesor, visitas frecuentes.O artigo é o resultado de uma investigação para a qual foram pesquisados e entrevistados os chefes de compras das pequenas, médias e grandes empresas industriais de Cali e de Yumbo com o objetivo de identificar as variáveis que influenciam a decisão de compra de produtos industriais, tais como: matérias primas, produtos de ferragens, peças, manutenção e reparação de maquinaria. Identificamos o nível de importância que o comprador dá no momento de tomar sua decisão de compra à proximidade, ao nível de desenvolvimento tecnológico do fornecedor, ao preço, prazo de entrega, qualidade do produto, garantia, certificação de qualidade, cumprimento e pontualidade, crédito, confidencialidade, confiabilidade, atenção personalizada, assessoria técnica, atendimento fora do horário comercial e fins de semana ou feriados, serviço pós venda, transporte próprio, grau de amizade com o vendedor, formação por parte do fornecedor, origem do produto (nacional ou importado), práticas éticas por parte do fornecedor, dimensão do fornecedor, nível de formação do orientador, visitas freqüentes

Photocatalytic ethanol oxidative dehydrogenation over Pt/TiO 2: Effect of the addition of blue phosphors

Ethanol oxidative dehydrogenation over Pt/TiO 2 photocatalyst, in the presence and absence of blue phosphors, was performed. The catalyst was prepared by photodeposition of Pt on sulphated TiO 2. This material was tested in a gas-solid photocatalytic fluidized bed reactor at high illumination efficiency. The effect of the addition of blue phosphors into the fluidized bed has been evaluated. The synthesized catalysts were extensively characterized by different techniques. Pt/TiO 2 with a loading of 0.5wt of Pt appeared to be an active photocatalyst in the selective partial oxidation of ethanol to acetaldehyde improving its activity and selectivity compared to pure TiO 2. In the same way, a notable enhancement of ethanol conversion in the presence of the blue phosphors has been obtained. The blue phosphors produced an increase in the level of ethanol conversion over the Pt/TiO 2 catalyst, keeping at the same time the high selectivity to acetaldehyde. Copyright © 2012 J. J. Murcia et al.Peer Reviewe

Substratum selection in coral reef sponges and their interactions with other benthic organisms

Substratum preferences and contact interactions among sessile organisms can be a major determinant of biotic gradients in the structure of benthic communities on coral reefs. Sponges are a substantial component of these communities, but their substratum requirements and interactions with other benthic taxa are poorly understood. Here, we quantified sponge substratum preferences and interactions from 838 randomly selected photo-quadrats across different depths (5, 10 and 15 m), exposure (sheltered and exposed), and substratum topography (horizontal, inclined and vertical surfaces) on coastal coral reefs in Kimbe Bay. A high proportion (55%) of sponge colonies were associated with dead coral, unconsolidated coral rubble (7%) and calcium carbonate rock (CaCO3 rock) (7%), even though they represented only 10%, 4% and 1% of the available substratum, respectively. Sponges interacted most frequently with algae (~ 34%), corals (~ 30%) and crustose coralline algae (CCA ~ 19%) that represented ~ 46%, ~ 18% and ~ 14% of the substratum cover, respectively. The microhabitat preferences of sponges and frequency of interactions with other taxa were mostly consistent across various exposure, depth and substratum topography conditions. Most interactions appeared to be “stand-offs” (71%) which are interactions with no clear winner or loser. However, when overgrowth occurred, sponges were usually winners, overgrowing corals (92%), CCA (81%) and macroalgae (65%). Three sponge species Dysidea sp1, Lamellodysidea cf. chlorea and Lamellodysidea chlorea accounted for 51% to 96% of the overgrowth of sponges over algae, corals and CCA, but there was no one species found to always win or lose. Our results suggest that sponges avoid other biological substrata by preferentially settling on dead coral, coral rubble and CaCO3 rock, but when they do come into contact with algae and corals, they frequently overgrow their spacial competitors

Osteitis condensante de clavícula

La osteítis condensante de clavícula es una lesión ósea infrecuente, benigna y de etiología desconocida. Se caracteriza por esclerosis densa y homogénea de la porción infero-medial clavicular con obliteración de la cavidad medular sin afectación de la articulación esternoclavicular. Hasta ahora sólo se había descrito en mujeres, en el presente trabajo presentamos un caso en un paciente varón. Se discute el diagnóstico diferencial con otras entidades que producen afectación similar y proponemos la TC como método diagnóstico de elección, defendiendo el tratamiento conservador.Condensing osteitis of the clavicle is a benign and uncommon bone lesion of unknown cause, characterized by homogeneously dense sclerotic patch with obliteration of the marrow cavity at the medial end of the clavicle without involvement of the sternoclavicular joint. To date it had been described only in women. In this work we report a case in a male patient. The differential diagnosis with other disorders of similar findings is discussed. We propose CT-scan as the elective diagnostic test and we defend the conservative treatment