531 research outputs found
El éxito lleva al éxito, especialmente cuando la autoeficacia se relaciona con una atribución interna de causalidad
Taking the Social Cognitive Theory by Albert Bandura as its starting point, this paper tests the hypothesis that academic self-efficacy influences future academic success through the differential impact of internal and external attribution of past success. Structural Equation Modelling performed with data from a longitudinal sample of 527 university students provides strong evidence supporting the research model. These findings show that past academic success has a positive influence on academic self-efficacy (p < .001) and on future academic success (p < .001). Two processes can then occur: (1) when self-efficacy is related with an internal attribution (p < .001) it has a positive impact on future academic success over time (p < .001); (2) when self-efficacy is related with an external attribution (p < .001) it has a negative impact on future academic success (p < .05). Theoretical and practical implications, as well as its limitations and future research, are discussed.Considerando la Teoría Cognitiva Social de Albert Bandura, el presente trabajo pone a prueba la hipótesis de que la autoeficacia académica influye en el éxito académico futuro a través del impacto diferencial de la atribución interna y externa de los éxitos pasados. Modelos de Ecuaciones Estructurales en una muestra longitudinal de 527 estudiantes universitarios apoyan el modelo de investigación. Estos resultados muestran que el éxito académico pasado tiene una influencia positiva sobre la autoeficacia académica (p < .001) y sobre el éxito académico futuro (p < .001). Dos procesos pueden entonces ocurrir: (1) cuando la autoeficacia se relaciona con una atribución interna (p < .001) se muestra un impacto positivo sobre el éxito académico futuro a lo largo del tiempo (p < .001); (2) cuando la autoeficacia se relaciona con una atribución externa (p < .001) el impacto sobre el éxito académico futuro es negativo (p < .05). Se discuten las implicaciones de los resultados, sus limitaciones e investigación futura
Análisis de chapas trapezoidales de acero conformado en frio mediante el método de los elementos finitos
En el presente proyecto se ha desarrollado un procedimiento para el análisis de chapas
trapezoidales de acero conformado en frío mediante el método de los elementos finitos.
En concreto se ha estudiado el comportamiento en el colapso de las chapas sometidas a flexión centrándonos en las diferentes posibilidades de modelización y los distintos parámetros que influyen en ella. Más que un estudio teórico en profundidad de los fenómenos que
intervienen en el colapso de las chapas, el objetivo ha sido estudiar la modelización de dichos fenómenos.
Para realizar el análisis final de las chapas se han estudiado por pasos los diferentes componentes que las conforman. Esto se ha hecho así con el objetivo de facilitar el análisis de los diferentes fenómenos que intervienen y tener una idea más clara de cuál es el mejor
método de simulación.
Las diferentes partes en que puede dividirse una chapa trapezoidal serían perfiles (una ondade la chapa) y placas individuales (elementos de sección). Los fenómenos que se producen durante el colapso de las chapas son de inestabilidad y
formación de rótulas plásticas. Por esta razón, se han estudiado diferentes modos de
inestabilidad y configuraciones de líneas de plastificación.
Como comprobación final de la modelización de dichos fenómenos sobre la chapa se ha
realizado un ensayo experimental con el que se han comparado los resultados
Conocimiento y percepción de la Inteligencia Emocional en la gestión de la salud ocupacional
Introducción: El concepto de Inteligencia Emocional (IE) ha ido ganando relevancia, considerándose un constructo importante en contextos laborales, sobre todo relacionándolo con la salud y el bienestar en el trabajo. El interés por la prevención de riesgos laborales y la investigación relativa a factores psicosociales, muestran la importancia de considerar la Ie en los procesos de evaluación e intervención dirigidos a optimizar el bienestar psicosocial. Sin embargo, el nivel de conocimiento de estos temas entre los profesionales de Recursos Humanos es desigual y, desafortunadamente, en algunos casos bastante bajo. El objetivo general de este trabajo es analizar el conocimiento y la percepción de estos profesionales acerca de las temáticas de Ie como variable de interés en la prevención de riesgos psicosociales en las organizaciones. Método: Una muestra de 122 participantes (102 profesionales de Recursos Humanos y una muestra adicional de 20 estudiantes) cumplimentó un cuestionario online ad hoc. El cuestionario consistía en diferentes preguntas acerca del conocimiento, uso y percepción de las prácticas de Ie por parte de los responsables de RRHH., PRL y CEOS. Resultados: Se observa que un 60% de los profesionales conoce las prácticas de Ie y sus beneficios, siendo este conocimiento mayor en los estudiantes, con un 76,2%. Otros resultados se refieren a las diferencias en función del género respecto a la aplicación y percepción de las prácticas de Ie, siendo las mujeres las que muestran mayor conocimiento de estas prácticas. Conclusiones: Debe potenciarse la investigación y difusión de resultados en esta línea, con el fin de aumentar el conocimiento y aplicación de las prácticas de IE.Introduction: The concept of Emotional Intelligence (eI) has become highly relevant, being considered an important construct in work contexts, especially in health and wellbeing at work. Interest in prevention of occupational risks empirical and research about psychosocial factors show the importance of considering eI in the evaluation and intervention processes aimed to optimize psychosocial. However, the level of knowledge of these issues among Human Resources professionals is uneven and, unfortunately, in some cases quite low. The general objective of this work is to analyze the knowledge and perception about eI of these professionals as a variable of interest in the prevention of psychosocial risks at organizations. Method: A sample of 122 participants (120 Human Resources professionals and an additional sample of 20 students) completed an ad hoc online questionnaire. The questionnaire consisted of different questions about the knowledge, usage, and perception of eI practices by professionals of HR, PLR, and CEOS. Results: It is observed that 60% of professionals know about EI practices and its benefits, being this knowledge greater in students, with 76,2%. Other results refer to gender differences regarding application and perception of eI practices, being women the ones who show greater knowledge of these practices. Conclusions: Research and dissemination of results in this line should be promoted, in order to increase knowledge and application of eI practices
Dewaterability of sewage sludge by ultrasonic, thermal and chemical treatments
Sludges resulting from wastewater treatment processes have a characteristically high water content, which complicates handling operations such as pumping, transport and disposal. To enhance the dewatering of secondary sludge, the effect of ultrasound waves, thermal treatment and chemical conditioning with NaOH have been studied. Two features of treated sludges were examined: their rheological behavior and their dewaterability. The rheological tests consisted of recording shear stress when the shear rate increases and decreases continuously and linearly with time, and when it increases and decreases in steps. Steady-state viscosity and thixotropy were obtained from the rheological tests, and both decreased significantly in all cases with increased treatment intensity. Centrifugation of ultrasonicated and thermally treated sludges allowed the total solid content to be increased by approximately 16.2% and 17.6%, respectively. These dewatered sludges had a lower viscosity and thixotropy than the untreated sludge. In contrast, alkali conditioning barely allowed the sludge to be dewatered by centrifugation, despite decreasing its viscosity and thixotropy
Flow colectivo en equipos de trabajo que utilizan tecnologías
Decenes Jornades de Foment de la Investigació de la FCHS (Any 2004-2005)Cada vez más se está otorgando una mayor importancia a la capacidad de las personas para trabajar
en equipo, tanto a nivel académico como a nivel organizacional. Este hecho remarca la necesidad
de investigar acerca de cómo organizar y cómo optimizar ese trabajo en equipo. La presente investigación
se encuadra desde el contexto de la Psicología Organizacional Positiva, donde cobra sentido
el concepto de ‘flow colectivo’. El Flow es una “experiencia óptima extremadamente disfrutada. Se
experimenta total concentración y disfrute con un alto interés por la actividad en si misma” (Moneta
y Csikszentmihalyi, 1996). Esta experiencia puede aparecer tanto en actividades de ocio como en
contextos laborales, y es en los contextos laborales donde se persigue estudiar el flow en equipos de
trabajo. Además existen estudios (Chen, Wigand y Nilan, 2000; Trevino y Webster, 1992) en los que se
ha encontrado muy relacionado el uso de las Tecnologías de la Información y Comunicación al hecho
de experimentar flow. Así pues el objetivo del presente estudio es analizar la existencia de diferencias
significativas en la experiencia de flow (absorción, interés intrínseco, disfrute) a través de un estudio
experimental longitudinal, en una muestra de 100 estudiantes de la Universitat Jaume I, evaluando las
dimensiones de flow a nivel colectivo, ya que los estudiantes realizaron tres tareas a nivel grupal. Así
mismo, se comparan dos condiciones: uso- no uso de la tecnología en la realización de la tarea (grupos
que realizaron las tareas utilizando el chat vs grupos que realizaron las tareas cara a cara). Por otro
lado, también se estudia la influencia del control del tiempo en la realización de las tareas (grupos con
la presión temporal vs grupos sin presión temporal). Los resultados muestran que no hay diferencias
significativas en las tres variables del flow en cuanto al uso o no uso de la tecnología. Sin embargo, si
observamos diferencias en cuanto a la presión temporal (tan sólo en las tareas 2 y 3) ya que los grupos
que tenían control de tiempo parece ser que tienen más probabilidades de experimentar flow colectivo.
Conclusiones e implicaciones teóricas y prácticas se desarrollan en el estudio
Effect of early development on semen parameters and lifespan of rabbit males selected by high growth rate
[EN] Life history theory suggests that different body development dynamics may influence survival and future reproductive performance of organisms. The present work studied how these dynamics could influence seminal traits and lifespan of rabbit males selected for growth rate and intended for Al. To achieve this goal, a total of 550 rabbit males were controlled from birth, evaluated both during the testing phase (four consecutive weeks after reaching 147 days of life) and the productive phase (377 of them from the end of the testing phase until 2 years of life). In order to obtain individuals with different body development dynamics, we pre-selected males based on their live weight (LW) at 0, 28, 63 and 147 days and on their average daily gain (ADG) between each period (0-28, 28-63 and 63-147 days). Libido and main seminal traits (semen volume, motility, concentration, and production, as well as normal apical ridge and abnormalities of spermatozoa) were controlled during the testing phase. Semen volume, motility and concentration were subsequently controlled during the productive phase, as well as the length of the male life, calculated as the number of days a rabbit was present at the farm between age 147 and day of death, culling or censoring; set to 2 years of life). The birth weight, the ADG between 0 and 28 days and between 28 and 63 days were positively related to some seminal parameters measured during the testing phase (semen volume, concentration, production and motility; P<0.05), while the ADG between 63 and 147 days was negatively related to the seminal productivity throughout the productive life of the males (an increment of 10 g per day on ADG reduced the number of profitable ejaculates by 4.9%; P<0.05). In addition, a higher growth between 0 and 28 and between 63 and 147 days increased the risk of death or culling of males during the productive phase (P < 0.05). In conclusion, an adequate body development early in life seems to have a positive effect on the degree of sexual maturity with which male rabbits begin their reproductive life, but reaching the reproduction onset with excessive weight can reduce their reproductive performance and lifespan. (C) 2019 Elsevier Inc. All rights reserved.The authors would like to thank Jose Manuel Arias, owner of the selection centre El Adil Redondo S.L., (Carrizo de la Ribera, Leon, Spain), and his team for their help, as without their collaboration this work could not have been carried out. This study was supported by the Interministerial Commission for Science and Technology (CICYT) of the Spanish Government (AGL2017-85162-C2-1-R).Martinez-Paredes, E.; Llorens, J.; Ródenas Martínez, L.; Savietto, D.; Pascual Amorós, JJ. (2019). Effect of early development on semen parameters and lifespan of rabbit males selected by high growth rate. Theriogenology. 139:72-80. https://doi.org/10.1016/j.theriogenology.2019.07.014S728013
SAVASA project @ TRECVID 2012: interactive surveillance event detection
In this paper we describe our participation in the interactive surveillance event detection task at TRECVid 2012. The system we developed was comprised of individual classifiers brought together behind a simple video search interface that enabled users to select relevant segments based on down~sampled animated gifs. Two types of user -- `experts' and `end users' -- performed the evaluations. Due to time constraints we focussed on three events -- ObjectPut, PersonRuns and Pointing -- and two of the five available cameras (1 and 3). Results from the interactive runs as well as discussion of the performance of the underlying retrospective classifiers are presented
Independent Validation of the SEND-PD and Correlation with the MDS-UPDRS Part IA
Introduction. Neuropsychiatric symptoms in Parkinson's disease can be assessed by the MDS-UPDRS part IA. The Scale for Evaluation of Neuropsychiatric Disorders in Parkinson's disease (SEND-PD) has been recently developed to assess the severity of some neuropsychiatric symptoms. The objective of this study is to compare the performance of the SEND-PD with the corresponding items of the MDS-UPDRS part IA. Methods. Patients with Parkinson's disease were evaluated using the MDS-UPDRS and the SEND-PD by independent raters. Partial SEND-PD and neuropsychiatric MDS-UPDRS part IA were constructed with equivalent items for comparison. Results. A total of 260 consecutive patients were included. Overall, 61.2% of the patients did not report any psychotic symptom and 83.5% did not report any ICD symptom. On the other hand, 78.5% of the patients did report at least one symptom related to apathy, depression, or anxiety. The partial SEND-PD score was 2.9 ± 3.1 (range from 0 to 16). The neuropsychiatric MDS-UPDRS part IA score was 2.9 ± 3 (range from 0 to 14). The correlation coefficient between corresponding items ranged from 0.67 to 0.98 and between both summary indexes was r s = 0.93 (all, P < 0.001). Conclusion. A high association between equivalent items of the SEND-PD and the MDS-UPDRS was found.S
Diagnostic Ability of Macular Nerve Fiber Layer Thickness Using New Segmentation Software in Glaucoma Suspects
Purpose. To assess the capacity of internal retinal layer thickness measurements made at the macula using new spectral-domain optical coherence tomography (OCT) software to distinguish between healthy subjects and those with suspected glaucoma. The diagnostic performance of such measurements also was compared with that of conventional peripapillary retinal nerve fiber layer (RNFL) thickness measurements.
Methods. The study included 38 subjects with suspected glaucoma and 38 age-matched healthy subjects. In one randomly selected eye of each participant, thickness measurements at the level of the macula were made of the nerve fiber layer (mRNFL), the ganglion cell layer (GCL), and the ganglion cell complex (GCC; GCL + internal plexiform layer) through automated OCT segmentation. Peripapillary RNFL thickness (pRNFL) also was determined using the conventional scan.
Results. As the only variable showing intergroup variation, mRNFL in the glaucoma suspects was significantly thinner in the quadrants inner inferior (P = 0.003), inner temporal (P = 0.010), and outer inferior (P = 0.017). The variable best able to discriminate between the two groups was inner inferior mRNFL thickness, as indicated by an area below the receiver operating characteristic (ROC) curve of 0.742.
Conclusions. Macular RNFL thickness measurements showed an improved diagnostic capacity over the other variables examined to distinguish between healthy subjects and glaucoma suspects
Visual outcomes after bilateral trifocal diffractive intraocular lens implantation
Background
In recent years new models of intraocular lenses are appearing on the market to reduce requirements for additional optical correction. The purpose of this study is to assess visual outcomes following bilateral cataract surgery and the implant of a FineVision® trifocal intraocular lens (IOL).
Methods
Prospective, nonrandomized, observational study. Vision was assessed in 44 eyes of 22 patients (mean age 68.4 ± 5.5 years) before and 3 months after surgery. Aberrations were determined using the Topcon KR-1 W wave-front analyzer. LogMAR visual acuity was measured at distance (corrected distance visual acuity, CDVA 4 m), intermediate (distance corrected intermediate visual acuity, DCIVA 60 cm) and near (distance corrected near visual acuity, DCNVA 40 cm). The Pelli-Robson letter chart and the CSV-1000 test were used to estimate contrast sensitivity (CS). Defocus curve testing was performed in photopic and mesopic conditions. Adverse photic phenomena were assessed using the Halo v1.0 program.
Results
Mean aberration values for a mesopic pupil diameter were: total HOA RMS: 0.41 ± 0.30 μm, coma: 0.32 ± 0.22 μm and spherical aberration: 0.21 ± 0.20 μm. Binocular logMAR measurements were: CDVA −0.05 ± 0.05, DCIVA 0.15 ± 0.10, and DCNVA 0.06 ± 0.10. Mean Pelli-Robson CS was 1.40 ± 0.14 log units. Mean CSV100 CS for the 4 frequencies examined (A: 3 cycles/degree (cpd), B: 6 cpd, C: 12 cpd, D: 18 cpd) were 1.64 ± 0.14, 1.77 ± 0.18, 1.44 ± 0.24 and 0.98 ± 0.24 log units, respectively. Significant differences were observed in defocus curves for photopic and mesopic conditions (p < 0.0001). A mean disturbance index of 0.28 ± 0.22 was obtained.
Conclusions
Bilateral FineVision IOL implant achieved a full range of adequate vision, satisfactory contrast sensitivity, and a lack of significant adverse photic phenomena.
Trial registration
Eudract Clinical Trials Registry Number: 2014-003266-2
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