GPGPU implementation of growing neural gas: application to 3D scene reconstruction

Self-organising neural models have the ability to provide a good representation of the input space. In particular the Growing Neural Gas (GNG) is a suitable model because of its flexibility, rapid adaptation and excellent quality of representation. However, this type of learning is time-consuming, especially for high-dimensional input data. Since real applications often work under time constraints, it is necessary to adapt the learning process in order to complete it in a predefined time. This paper proposes a Graphics Processing Unit (GPU) parallel implementation of the GNG with Compute Unified Device Architecture (CUDA). In contrast to existing algorithms, the proposed GPU implementation allows the acceleration of the learning process keeping a good quality of representation. Comparative experiments using iterative, parallel and hybrid implementations are carried out to demonstrate the effectiveness of CUDA implementation. The results show that GNG learning with the proposed implementation achieves a speed-up of 6× compared with the single-threaded CPU implementation. GPU implementation has also been applied to a real application with time constraints: acceleration of 3D scene reconstruction for egomotion, in order to validate the proposal.

Psychometric properties of the School Anxiety Inventory-Short Version in Spanish secondary education students

Background: The School Anxiety Inventory (SAI) can be applied in different fields of psychology. However, due to the inventory’s administration time, it may not be useful in certain situations. To address this concern, the present study developed a short version of the SAI (the SAI-SV). Method: This study examined the reliability and validity evidence drawn from the scores of the School Anxiety Inventory-Short Version (SAI-SV) using a sample of 2,367 (47.91% boys) Spanish secondary school students, ranging from 12 to 18 years of age. To analyze the dimensional structure of the SAI-SV, exploratory and confirmatory factor analyses were applied. Internal consistency and test-retest reliability were calculated for SAISV scores. Results: A correlated three-factor structure related to school situations (Anxiety about Aggression, Anxiety about Social Evaluation, and Anxiety about Academic Failure) and a three-factor structure related to the response systems of anxiety (Physiological Anxiety, Cognitive Anxiety, and Behavioral Anxiety) were identified and supported. The internal consistency and test-retest reliability were determined to be appropriate. Conclusions: The reliability and validity evidence based on the internal structure of SAI-SV scores was satisfactory.

Is there any evidence for the validity of diagnostic criteria used for accommodative and nonstrabismic binocular dysfunctions?

Purpose: To analyze the diagnostic criteria used in the scientific literature published in the past 25 years for accommodative and nonstrabismic binocular dysfunctions and to explore if the epidemiological analysis of diagnostic validity has been used to propose which clinical criteria should be used for diagnostic purposes. Methods: We carried out a systematic review of papers on accommodative and non-strabic binocular disorders published from 1986 to 2012 analysing the MEDLINE, CINAHL, PsycINFO and FRANCIS databases. We admitted original articles about diagnosis of these anomalies in any population. We identified 839 articles and 12 studies were included. The quality of included articles was assessed using the QUADAS-2 tool. Results: The review shows a wide range of clinical signs and cut-off points between authors. Only 3 studies (regarding accommodative anomalies) assessed diagnostic accuracy of clinical signs. Their results suggest using the accommodative amplitude and monocular accommodative facility for diagnosing accommodative insufficiency and a high positive relative accommodation for accommodative excess. The remaining 9 articles did not analyze diagnostic accuracy, assessing a diagnosis with the criteria the authors considered. We also found differences between studies in the way of considering patients’ symptomatology. 3 studies of 12 analyzed, performed a validation of a symptom survey used for convergence insufficiency. Conclusions: Scientific literature reveals differences between authors according to diagnostic criteria for accommodative and nonstrabismic binocular dysfunctions. Diagnostic accuracy studies show that there is only certain evidence for accommodative conditions. For binocular anomalies there is only evidence about a validated questionnaire for convergence insufficiency with no data of diagnostic accuracy.

Noticias sobre el virus del papiloma humano y su vacuna en la prensa valenciana (2006-2011)

La introducción de la vacuna contra el virus del papiloma humano (VPH) dirigida a mujeres adolescentes ha tenido en España un desarrollo no exento de cierta controversia. Asociada inicialmente al mensaje de «vacuna contra el cáncer de útero» que ofrecía una nueva posibilidad de lucha contra esa enfermedad, obtuvo una réplica que moderaba la euforia con un mensaje dirigido a probar evidencias. Mientras se administraba la segunda dosis de vacuna (febrero de 2009) ocurrió un suceso inesperado en Valencia relacionado con la aparición de acontecimientos adversos tras la administración de la vacuna en dos adolescentes, que tuvo un explosivo tratamiento mediático. Este estudio analiza el alcance y el contenido de las noticias aparecidas en dos periódicos regionales valencianos de gran tirada durante el sexenio 2006-2011 que mencionan al VPH, su vacuna y el cáncer de útero. Se discute la influencia que los mensajes emitidos hayan podido tener en la aceptabilidad de la vacuna.

Seismic behavior of a masonry chimney with severe cracking condition: preliminary study

This paper presents a structural analysis of a masonry chimney built in the 1940s, which is currently being cataloged as local interest heritage. This structure has not served any industrial purpose for the last thirty years. The chimney is located in the town of Agost (Alicante - Spain) and directly exposed to the prevailing winds from the sea, as it is approximately 12 km away from the waterfront and there are not any significant barriers, which could protect the structure against the wind. There are longitudinal cracks and fissures all along the shaft because of the chimney’s geometrical characteristics, the effect of the masonry creep and especially the lack of maintenance. Moreover, there is also a permanent bending deformation in the upper 1/3 of the height due to the wind pressure. A numerical analysis for the static behavior against gravity and wind loads was performed using the structure’s current conditions after a detailed report of its geometry, its construction system and the cracking pattern. Afterwards, the dynamic behavior was studied, i.e. a seismic analysis using both response spectra and accelerograms in order to examine the structural stability. This work shows the pre-monitoring analysis before any experimental testing. Using the current results the future test conditions will be determined (e.g. number of sensors and monitoring point location, excitation systems, etc) prior to a possible structural reinforcement by applying composite material (fiber reinforced polymers).

Effects of whole body vibration on strength and jumping performance in volleyball and beach volleyball players

The primary aim of this study was to examine the effects of 6-week strength training with whole body vibration (WBV) on leg strength and jumping performance in volleyball and beach volleyball players. Twenty-three sub-elite male volleyball (VB; n=12) and beach volleyball players (BVB; n=11) aged 21.2±3.0 years were divided into two groups and subjected to 6 weeks of strength training (three one-hour sessions per week): (I) 12 players (6 VB and 6 BVB players) underwent training with WBV (30-40 Hz, 1.7-2.5 mm, 3.0-5.7 g), and (II) 11 players (6 VB and 5 BVB players) underwent traditional strength training. Squat jump (SJ) and countermovement squat jump (CMJ) measurements by the Ergo Tester contact platform and maximum leg press test (1RM) were conducted. Three-factor (2 time x 2 WBV use x 2 discipline) analysis of variance for SJ, CMJ and 1RM revealed a significant time main effect (p<0.001), a WBV use effect (p<0.001) and a discipline effect (p<0.001). Significantly greater improvements in the SJ (p<0.001) and CMJ (p<0.001) and in 1RM (p<0.001) were found in the WBV training groups than in traditional training groups. Significant 3-way interaction effects (training, WBV use, discipline kind) were also found for SJ, CMJ and 1RM (p=0.001, p<0.001, p=0.001, respectively). It can be concluded that implementation of 6-week WBV training in routine practice in volleyball and beach volleyball players increases leg strength more and leads to greater improvement in jump performance than traditional strength training, but greater improvements can be expected in beach volleyball players than in volleyball players.

Psychometric properties of the Spanish adaptation of the School Attitude Assessment Survey-Revised

Background: The assessment of attitudes toward school with the objective of identifying adolescents who may be at risk of underachievement has become an important area of research in educational psychology, although few specific tools for their evaluation have been designed to date. One of the instruments available is the School Attitude Assessment Survey-Revised (SAAS-R). Method: The objective of the current research is to test the construct validity and to analyze the psychometric properties of the Spanish version of the SAAS-R. Data were collected from 1,398 students attending different high schools. Students completed the SAAS-R along with measures of the g factor, and academic achievement was obtained from school records. Results: Confirmatory factor analysis, multivariate analysis of variance and analysis of variance tests supported the validity evidence. Conclusions: The results indicate that the Spanish version of the SAAS-R is a useful measure that contributes to identification of underachieving students. Lastly, the results obtained and their implications for education are discussed.

Consequences of Kondo exchange on quantum spins

When individual quantum spins are placed in close proximity to conducting substrates, the localized spin is coupled to the nearby itinerant conduction electrons via Kondo exchange. In the strong coupling limit this can result in the Kondo effect — the formation of a correlated, many body singlet state — and a resulting renormalization of the density of states near the Fermi energy. However, even when Kondo screening does not occur, Kondo exchange can give rise to a wide variety of other phenomena. In addition to the well known renormalization of the g factor and the finite spin decoherence and relaxation times, Kondo exchange has recently been found to give rise to a newly discovered effect: the renormalization of the single ion magnetic anisotropy. Here we put these apparently different phenomena on equal footing by treating the effect of Kondo exchange perturbatively. In this formalism, the central quantity is ρJ, the product of the density of states at the Fermi energy ρ and the Kondo exchange constant J. We show that perturbation theory correctly describes the experimentally observed exchange induced shifts of the single spin excitation energies, demonstrating that Kondo exchange can be used to tune the effective magnetic anisotropy of a single spin.

Relevancia del papel del planificador estratégico en la investigación publicitaria

La investigación sobre el consumidor ha sido el eje central del trabajo del planificador estratégico desde el nacimiento de la profesión en 1968. En concreto, en el origen de la disciplina de la Planificación Estratégica está la relevancia de la investigación cualitativa como fuente fiable para conocer en profundidad al consumidor y poder desarrollar campañas de comunicación eficaces, relevantes y distintivas. Por ello, y por la repercusión que tiene el conocimiento profundo del consumidor hoy en día, se va a hacer un repaso bibliográfico por las funciones que tradicionalmente ha adquirido el planificador en relación a la investigación para después aplicarlo a la realidad española actual a partir de un estudio empírico a los planificadores estratégicos españoles. El artículo termina con una reflexión sobre el papel relevante que el planner tendrá en un futuro muy próximo en el panorama de Big Data.

El espacio del agua en la ciudad de Orihuela en época islámica

Análisis de los datos que proporcionan la arqueología y las fuentes escritas acerca de las diversas funcionalidades del agua en el espacio urbano de Orihuela en el período andalusí. Se dividen en funcionalidades primarias (alimentación y limpieza) y funcionalidades económicas (agricultura y artesanías). Se clasifican al final los datos que poseemos sobre los elementos del espacio del agua de la Orihuela musulmana.

La representación mediática del deportista con discapacidad en el reportaje televisivo. Informe Semanal, un estudio de caso

El tratamiento informativo de los Juegos Paralímpicos de 2008 en los medios españoles aparece ligado casi exclusivamente a los valores asociados al universo deportivo, según un estudio previo. Los paralímpicos son atletas, no personas con discapacidad. Ni se tendió al sensacionalismo ni se ofreció una imagen estereotipada. Debido a la particularidad del acontecimiento, también desaparecen reivindicaciones y problemas. Se trata de información deportiva en la que importa el resultado, los éxitos, las medallas. Para profundizar en la comprensión de la representación televisiva de los deportistas con discapacidad, el objeto de estudio es ahora la información televisiva al margen de la dinámica noticiosa de la cobertura diaria de los Juegos. El análisis de otro tipo de piezas, reportajes, ha permitido descubrir marcas tendentes a la estereotipación vinculadas al campo semántico periodístico, aquel que se hace visible a través del uso de recursos que propician la emotividad y la espectacularización. Emergen las historias de vida y detalles íntimos. Los protagonistas muestran una gran autoestima y una autoidentidad positiva al alejarse de las representaciones sociales habituales de la discapacidad.

Percepción de las enfermeras de atención especializada sobre la prescripción enfermera

El objetivo de esta investigación fue determinar la percepción que sobre el concepto de “prescripción enfermera” tienen los profesionales enfermeros de atención especializada. Para ello se realizó un abordaje cualitativo mediante técnica Delphi, con la participación de 20 profesionales enfermeros que constituyeron el grupo de expertos. El período de estudio estuvo comprendido entre diciembre de 2008 y febrero de 2009 y se desarrolló en un hospital de tercer nivel de la Comunidad de Madrid. Se identificaron 17 actividades que fueron entendidas por el grupo de expertos como prescripción enfermera, siendo éstas agrupadas con arreglo a tres categorías: prescripción independiente, colaborativa y basándose en un protocolo. El grupo de expertos consideró que dichas actividades pueden ser desarrolladas mediante dos perfiles competenciales enfermeros: el perfil administrativo y el facultativo.

Experiencia de transferencia de conocimiento en el proyecto de investigación ITSAL (Inmigración, Trabajo y SALud) con representantes de la población diana

Se describe una experiencia de transferencia de conocimiento entre investigadores del proyecto ITSAL (Inmigración, Trabajo y SALud) y representantes de asociaciones que trabajan con población inmigrante para discutir los resultados obtenidos en esta investigación y las líneas de futuro. Para ello se llevó a cabo una reunión en la que participaron tres investigadoras y 18 representantes de 11 instituciones. Tras una exposición de la metodología y los resultados del proyecto ITSAL, todos los asistentes comentaron los resultados presentados y líneas de investigación de interés. Se pusieron de manifiesto coincidencias entre ambas partes y también se obtuvieron propuestas de interés para el proyecto ITSAL. Entendemos el proceso descrito como una aproximación a la validación social de algunos resultados principales del proyecto. Esta experiencia nos ha permitido abrir un canal de comunicación con la población diana del estudio, en línea con la necesaria interacción de investigadores y población.

The Influence of Gender, Intellectual Ability, Academic Self-Concept, Self-Regulation, Learning Strategies, Popularity and Parent Involvement in Early Adolescence

The present study examined the predictive effects of gender, intellectual ability, self-concept, motivation, learning strategies, popularity and parent involvement on academic achievement. Hiearchical regression analysis were performed with six steps in which each variable was included, among a sample of 1398 high school students (mean age = 12.5; standard deviation = .67) of eight education centers from the province of Alicante (Spain). The results revealed significant predictive effects of all of the variables, explaining 59.1% of the total variance.

Shape Effect of Electrochemical Chloride Extraction in Structural Reinforced Concrete Elements Using a New Cement-Based Anodic System

This article shows the research carried out by the authors focused on how the shape of structural reinforced concrete elements treated with electrochemical chloride extraction can affect the efficiency of this process. Assuming the current use of different anode systems, the present study considers the comparison of results between conventional anodes based on Ti-RuO2 wire mesh and a cement-based anodic system such as a paste of graphite-cement. Reinforced concrete elements of a meter length were molded to serve as laboratory specimens, to closely represent authentic structural supports, with circular and rectangular sections. Results confirm almost equal performances for both types of anode systems when electrochemical chloride extraction is applied to isotropic structural elements. In the case of anisotropic ones, such as rectangular sections with no uniformly distributed rebar, differences in electrical flow density were detected during the treatment. Those differences were more extreme for Ti-RuO2 mesh anode system. This particular shape effect is evidenced by obtaining the efficiencies of electrochemical chloride extraction in different points of specimens.