Characterizing the executive functioning associated with dispositional mindfulness

Previous research shows that dispositional mindfulness is related to cognitive aspects. The relationship between executive functions and dispositional mindfulness is poorly studied. The aim of this work is to characterize the executive functioning associated with dispositional mindfulness. Dispositional mindfulness was evaluated in 90 undergraduates through the Mindful Attention Awareness Scale. In addition, inhibition (Stroop task), cognitive flexibility (rule shift cards), processing speed (digit symbol substitution test), planning (zoo map test) and abstract reasoning (similarities test) were used to evaluate executive function. A multiple hierarchical regression analysis was carried out to predict dispositional mindfulness based on performance in the executive function tests and the individual’s age and sex. Age and sex accounted for 0.7% of dispositional mindfulness. Inhibition and cognitive flexibility accounted for 10.8% and 6%, respectively, of dispositional mindfulness, while processing speed and abstract reasoning explained 3.5% and 0.8%, respectively. Lastly, planning accounted for 0% of dispositional mindfulness. Individual differences in self-reported dispositional mindfulness may be caused by differences in executive performance. The good management of cognitive flexibility, the ability to inhibit and the ability to process stimuli more quickly play a crucial role in attending to current experience

Stress estimation by the prefrontal cortex asymmetry: Study on fNIRS signals

sure the brain hemodynamic activity in applications to evaluate affective disorders and stress. Using two wavelengths of light, it is possible to monitor relative changes in the concentrations of oxyhemoglobin and deoxyhemoglobin. Besides, the spatial asymmetry in the prefrontal cortex activity has been correlated with the brain response to stressful situations. Methods: We measured prefrontal cortex activity with a NIRS multi-distance device during a baseline period, under stressful conditions (e.g., social stress), and after a recovery phase. We calculated a laterality index for the contaminated brain signal and for the brain signal where we removed the influence of extracerebral hemodynamic activity by using a short channel. Results: There was a significant right lateralization during stress when using the contaminated signals, consistent with previous investigations, but this significant difference disappeared using the corrected signals. Indeed, exploration of the susceptibility to contamination of the different channels showed non-homogeneous spatial patterns, which would hint at detection of stress from extracerebral activity from the forehead. Limitations: There was no recovery phase between the social and the arithmetic stressor, a cumulative effect was not considered. Conclusions: Extracerebral hemodynamic activity provided insights into the pertinence of short channel corrections in fNIRS studies dealing with emotions. It is important to consider this issue in clinical applications including modern monitoring systems based on fNIRS technique to assess emotional states in affective disorders

Regulação de frequência em sistemas de potência que integram fontes de energias eólicas mediante um controlador pi e imitação de inercial

Introduction: This article derives from the research “Multilevel Control for Microgrids Dispatch Considering Stability Issues through mpc -based Frequency Regulation” conducted at the Universidad Nacional de Colombia during 2016 and the first half of 2017. It presents the study and analysis of a frequency regulation control scheme implemented in a power system that integrates renewable energy sources (res). The objective is to improve the reliability and stability of the grid against typical disturbances of renewable energies. Methodology: Initially, the dynamic response of the power system to sudden disturbances and continuous change was simulated to observe frequency deviations. The control block was also implemented in the additional power loop to emulate inertia and, thus, slow down the response of the system. Subsequently, the control parameters were optimized through heuristic optimization algorithms to minimize the frequency signal error. Results: Using the heuristic optimization of proportional integral (pi) control parameters, it was verified that there is a reduction of more than 79 % in the maximum error of frequency deviation in relation to the open loop response, and more than 43 % with respect to pi control with referential gains. Conclusion: In implementing the additional power loop with pi control, a decrease in the frequency deviation error was found in relation to the open loop simulations, due to the additional power loop.Introducción: como producto de la investigación “Multilevel Control for Microgrids Dispatch Considering Stability Issues through MPC-based Frequency Regulation”, desarrollada en la Universidad Nacional de Colombia durante el 2016 y el primer semestre del 2017, se presenta el estudio y análisis de un esquema de control de regulación de frecuencia implementado en un sistema de potencia que integra fuentes de energías renovables (res). El objetivo es mejorar la confiabilidad y estabilidad de la red ante perturbaciones propias de las energías renovables. Metodología: inicialmente, se simuló la respuesta dinámica del sistema de potencia ante disturbios repentinos y de cambio continuo para observar las desviaciones de frecuencia. Así mismo, se implementó el bloque de control en el lazo de potencia adicional para emular la imitación inercial y, de esta manera, ralentizar la respuesta del sistema. Posteriormente, se procedió a optimizar los parámetros de control a través de algoritmos de optimización heurística para minimizar el error de la señal de frecuencia. Resultados: con la optimización heurística realizada a los parámetros de control proporcional-integral (PI), se comprobó que hay una reducción de más del 79% del error máximo de desviación de frecuencia en relación con la respuesta de lazo abierto, y más del 43% respecto al control pi con las ganancias referenciales. Conclusión: con la implementación del lazo de potencia adicional con control pi, se encontró una disminución del error de la desviación de frecuencia en relación con las simulaciones de lazo abierto, debido al lazo de potencia adicional.Introdução: o artigo é produto da pesquisa “Multilevel Control for Microgrids Dispatch Considering Stability Issues through mpc-based Frequency Regulation” desenvolvida na Universidade Nacional da Colômbia durante 2016 e o primeiro semestre de 2017. Apresenta-se o estudo e a análise de um esquema de controle de regulação de frequência implementado em um sistema de potência que integra fontes de energias renováveis (res). O objetivo é melhorar a confiabilidade e estabilidade da rede frente a perturbações próprias das energias renováveis. Metodologia: inicialmente, foi simulada a resposta dinâmica do sistema de potência frente a distúrbios repentinos e de mudança contínua para observar os desvios de frequência. Mesmo assim, foi implementado um bloco de controle no laço de potência adicional para simular a imitação inercial e, dessa maneira, desacelerar a resposta do sistema. Posteriormente, os parâmetros de controle foram otimizados através de algoritmos de aprimoramento heurístico para minimizar o erro do sinal de frequência. Resultados: com a otimização heurística realizada aos parâmetros de controle proporcional-integral (pi), comprovou-se que há uma redução de mais de 79% do erro máximo de desvio de frequência relacionado à resposta de laço aberto, e mais de 43% relacionado ao controle pi com os ganhos referenciais. Conclusão: com a implementação do laço de potência adicional com controle pi, foi encontrada uma diminuição do erro do desvio de frequência relacionadas às simulações de laço aberto, devido ao laço de potência adicional

La policía como actor político

PublishedLa novela de George Orwell (2010, p. 5) “1984” describe una sociedad bajo el control del Estado que determina cómo pensar, vivir, educarse, y en sí, comportarse, para preservar la convivencia social. Este texto comporta un antecedente presente en la sociedad del siglo XXI, que cada vez es más vigilada, recreando un aspecto de la sociedad que se pretende abordar: las instituciones de control social, en específico la Policía, vista como un actor que juega un papel preponderante en las relaciones sociopolíticas. La policía se recoge en los términos de Le Clere (1965, p 46) como unas entidades de diversas denominaciones: gendarmerías, milicias, cuerpos de seguridad y otras acepciones que han ejercido la función histórica del control en las civilizaciones primitivas, antiguas, modernas y contemporáneas

Frequency-domain analysis of fNIRS fluctuations induced by rhythmic mental arithmetic

Functional near-infrared spectroscopy (fNIRS) is an increasingly used technology for imaging neural correlates of cognitive processes. However, fNIRS signals are commonly impaired by task-evoked and spontaneous hemodynamic oscillations of non-cerebral origin, a major challenge in fNIRS research. In an attempt to isolate the task-evoked cortical response, we investigated the coupling between hemodynamic changes arising from superficial and deep layers during mental effort. For this aim, we applied a rhythmic mental arithmetic task to induce cyclic hemodynamic fluctuations suitable for effective frequency-resolved measurements. Twenty university students aged 18–25 years (eight males) underwent the task while hemodynamic changes were monitored in the forehead using a newly developed NIRS device, capable of multi-channel and multi-distance recordings. We found significant task-related fluctuations for oxy-and deoxy-hemoglobin, highly coherent across shallow and deep tissue layers, corroborating the strong influence of surface hemodynamics on deep fNIRS signals. Importantly, after removing such surface contamination by linear regression, we show that the frontopolar cortex response to a mental math task follows an unusual inverse oxygenation pattern. We confirm this finding by applying for the first time an alternative method to estimate the neural signal, based on transfer function analysis and phasor algebra. Altogether, our results demonstrate the feasibility of using a rhythmic mental task to impose an oscillatory state useful to separate true brain functional responses from those of non-cerebral origin. This separation appears to be essential for a better understanding of fNIRS data and to assess more precisely the dynamics of the neuro-visceral link

La arquitectura y construcción modular evaluada desde el triángulo de la triple restricción y aplicada al sector educativo en Colombia

Trabajo de investigaciónEste proyecto evalúa y compara el sistema de construcción modular con el sistema de construcción tradicional, analizado bajo el triángulo de la triple restricción de la guía PMBOK quinta edición, referido al análisis de alcance, tiempo y costo que cada sistema constructivo pueda llegar a alcanzar al finalizar su ejecución. Obteniendo indicadores reales que facilitan la toma de decisiones en la gestión de proyectos de educación superior en Colombia.INTRODUCCIÓN 1. GENERALIDADES 2. LEVANTAMIENTO DE INFORMACIÓN 3. CONCLUSIONES 4. RECOMENDACIONES BIBLIOGRAFÍA ANEXOSEspecializaciónEspecialista en Gerencia de Obras Civile

Factores que influyen en la intención emprendedora de estudiantes de psicología de la modalidad virtual

Most of the studies on entrepreneurial intention have been applied in university students under a face-to-face modality. However, it is also important to consider the context of the students in the virtual mode, that is, those students at a distance, so the objective of this study is to identify the most influential factors in the entrepreneurial intention of enrolled psychology university students in virtual mode. For this, a study with a quantitative approach is applied in which the Factorial Analysis statistical technique is used from the application of a survey to 178 psychology students from the Catholic North University Foundation. The convergent and discriminant validity of the proposed model is evaluated from the Theory of Planned Behavior and the Business Event Model, as well as the reliability and contrast of hypotheses. The results allow identifying relevant relationships between attitude, perceived behavior control, entrepreneurial behavior, and current behavior control with respect to the entrepreneurial intention of the surveyed students. Based on these results, it is possible to identify themost influential factors in the entrepreneurial intention of students, which allow strengthening from higher education institutions and universities the academic programs aimed at fostering the entrepreneurial spirit of psychology students in the virtual modality.La mayoría de los estudios sobre intención emprendedora se han aplicado a estudiantes universitarios en la modalidad presencial. Sin embargo, también es importante considerar el contexto de los estudiantes en la modalidad virtual, es decir, estudiantes a distancia, por lo que el objetivo de este estudio es identificar los factores más influyentes en la intención emprendedora de estudiantes universitarios de psicología inscritos en la modalidad virtual. Para esto, se aplica un estudio de enfoque cuantitativo en el cual se utiliza la técnica estadística Análisis Factorial a partir de la aplicación de una encuesta a 178 estudiantes de psicología de la Católica del Norte Fundación Universitaria. Se evalúa la validez convergente y discriminante del modelo propuesto a partir de la Teoría del Comportamiento Planificado y el Modelo del Evento Empresarial, así como la fiabilidad y contraste de hipótesis. Los resultados permiten identificar relaciones relevantes entre la actitud, el control de comportamientopercibido, el comportamiento emprendedor y el control de la conducta actual con respecto a la intención empresarial de los estudiantes encuestados. A partir de estos resultados es posible identificar los factores más influyentes en la intenciónemprendedora de los estudiantes, que permitan fortalecer desde las instituciones de educación superior y universidades los programas académicos orientados a fomentar el espíritu emprendedor de estudiantes de psicología en la modalidad virtual

Estrés percibido y quejas subjetivas de memoria en adultos jóvenes: papel mediador de las funciones ejecutivas

Introduction. Previous studies have shown that executive functions can be mediators between perceived stress and subjective memory complaints. However, it has not been evaluated which executive functions are those that most mediate this relationship. Aim. To determine if executive functions have a mediating role in the relationship between perceived stress and subjective memory complaints, and which ones have the greatest explanatory power. Patients and methods. The sample consisted of 743 university students (76.4% women), with an average age of 22.24 ± 3.64 years. The subjective memory complaints were evaluated with the Memory Failure of Everyday Questionnaire, the stress with the Perceived Stress Scale, and the executive functions with the Prefrontal Symptoms Inventory. Results. The executive functions and the perceived stress explained altogether 57% of the subjective memory complaints, being the attentional problems and the executive control problems the two variables with a greater weight in the model. On the other hand, the executive control problems, attentional problems and social behaviour problems showed a mediating effect between perceived stress and subjective memory complaints. Conclusions. The executive control problems and the attentional problems could be factors of choice for clinical intervention, since they act on their own as generators of subjective memory complaints and, moreover, are involved in mediation processes of perceived stress.IntroducciónEn estudios previos se ha señalado que las funciones ejecutivas pueden actuar como mediadoras entre el estrés percibido y las quejas subjetivas de memoria. Sin embargo, no se ha evaluado qué funciones ejecutivas son las que median en mayor medida dicha relación. ObjetivoDeterminar si las funciones ejecutivas tienen un papel mediador en la relación entre el estrés percibido y las quejas subjetivas de memoria, y cuáles son las que tienen un mayor poder explicativo. Pacientes y métodosLa muestra estuvo compuesta por 743 universitarios (76,4% mujeres), con una edad media de 22,24 ± 3,64 años. Las quejas subjetivas de memoria se evaluaron con el cuestionario de fallos de memoria de la vida cotidiana; el estrés, con la escala de estrés percibido; y las funciones ejecutivas, con el inventario de síntomas prefrontales. ResultadosLas funciones ejecutivas y el estrés percibido explicaron en conjunto un 57% de las quejas subjetivas de memoria, y los problemas atencionales y los problemas del control ejecutivo fueron las dos variables con un mayor peso en el modelo. Por otro lado, los problemas del control ejecutivo, los problemas atencionales y los problemas de la conducta social mostraron un efecto mediador entre el estrés percibido y las quejas subjetivas de memoria. Conclusiones Los problemas del control ejecutivo y los problemas atencionales podrían ser factores de elección para la intervención clínica, puesto que actúan por sí solos como generadores de quejas subjetivas de memoria y además se encuentran implicados en procesos de mediación del estrés percibido

Wind Power Variability and Singular Events

Examples of the different events affecting wind power fluctuations are shown.The behaviors and the responses of the Spanish power system and wind power plants experiencing such events were analyzed. Examples presented in this chapter show that some of the wind power integration issues are related to low-voltage ride-through. They are solved through strict grid code enforcement. Other solutions to manage the reserve power generation and the wind power fluctuations are also very important in order to achieve high levels of wind power penetration. In the Spanish case, this could require increasing the availability of dispatchable and fast-start power plants, as well as increasing wind power plant participation on supporting the power system by providing voltage control, inertial emulation, frequency control, oscillation damping, or updated voltage ride-through capabilities.Comment: Chapter of the Book 'Wind Power' (eBook (PDF) ISBN: 978-953-51-6418-0

Surface nanostructuring of TiO2 thin films by high energy ion irradiation

The effects of a high ion dose irradiation on TiO2 thin films under different conditions of temperature and ion nature are discussed. We have shown that anatase TiO2 thin films irradiated with N+ ions at room temperature develop a typical microstructure with mounds and voids open to the surface whereas irradiations at 700 K generate a surface pattern of well-ordered nanorods aligned with the ion beam. The formation of these patterns is caused by the simultaneous effect of ion irradiation near the film surface and a film temperature favoring the structural mobilization of the defective network of the material. To explain these phenomena, a qualitative model has been proposed and further tested by irradiating the TiO2 thin films with F+ and S+ ions under different conditions. The obtained results demonstrate that ion irradiation techniques enable the formation of tilted nanorod surface patterns with lengths of about 100 nm on anatase TiO2 thin films.Ministerio de Ciencia e Innovación MAT 2007-65764, 2010-CSD2008-00023, 200960I132Junta de Andalucía TEP2275, P07-FQM-0329