Using brain connectivity metrics from synchrostates to perform motor imagery classification in EEG-based BCI systems

Phase synchronisation between different neural groups is considered an important source of information to understand the underlying mechanisms of brain cognition. This Letter investigated phase-synchronisation patterns from electroencephalogram (EEG) signals recorded from ten healthy participants performing motor imagery (MI) tasks using schematic emotional faces as stimuli. These phase-synchronised states, named synchrostates, are specific for each cognitive task performed by the user. The maximum and minimum number of occurrence states were selected for each subject and task to extract the connectivity network measures based on graph theory to feed a set of classification algorithms. Two MI tasks were successfully classified with the highest accuracy of 85% with corresponding sensitivity and specificity of 85%. In this work, not only the performance of different supervised learning techniques was studied, as well as the optimal subset of features to obtain the best discrimination rates. The robustness of this classification method for MI tasks indicates the possibility of expanding its use for online classification of the brain-computer interface (BCI) systems

Deducción de colegiaturas de nivel superior para personas físicas

"En el presente trabajo de investigación se analizó la imposibilidad de las personas físicas, que sólo perciben ingresos por sueldos y salarios, de hacer deducibles los pagos por servicios educativos, comúnmente llamadas colegiaturas, específicamente del nivel educativo superior, que incluye a los programas de licenciatura y posgrado, de acuerdo con las disposiciones fiscales vigentes en México al año 2020. Se abordó lo concerniente al ISR y sus elementos, a las deducciones aplicables para los contribuyentes personas físicas de acuerdo con el tipo de ingreso que obtengan, las deducciones personales que pueden aplicar y los requisitos establecidos para dichas deducciones. Además, se analizó el concepto de estímulo fiscal, sus elementos y el concepto de gasto tributario.

Connectivity analysis from EEG phase synchronisation in emotional BCI

A Brain Computer Interface (BCI) is a device that uses the brain activity of the user as an input to the system to select the desired output on a computer, giving the person a different pathway to establish communications with the surrounding environment. There are many types and uses of BCIs. They can be defined by which technique is used to record the brain activity of the user and which variety of stimuli is used to trigger a consistent response from the user, following the signal processing methodology selected to produce a response on the computer. Each one of the selected choices will determine the reliability and efficiency of the BCI system. However, even with this flexibility, the performance of BCI systems used for assistive technology or rehabilitation processes still remains behind other systems and the percentage of people unable to use one of these systems remains too high. The main objective of this thesis is to improve the classification performance and reliability of the current electroencephalogram (EEG) based BCI systems. Firstly, a novel paradigm based on emotional faces is used with the aim of enhancing a stronger response from the user, therefore a higher amplitude of brain activity. Two types of emotional faces have been used during this work. Initially, emotional schematic faces or emotions were used. Posteriorly, human emotional faces were introduced into the experiments. Additionally, the evolution of the phase synchronisation over time is studied to achieve a deeper understanding of the latent communication mechanisms of the different parts of the human brain. Wavelet families and their ability to retain temporal and frequency information simultaneously have been used to study the phase relationships between the EEG signals when a specific task is being performed. This study has led to the identification of a reduced number of discrete states with a quasi-stable phase synchronisation of the order of milliseconds, named synchrostates. Those synchrostates present switching patterns over time, clearly distinctive for each one of the tasks performed by the user. In order to establish a classification protocol the temporal stability of each task-specific synchrostate was studied by means of the synchronisation index and posteriorly translated into connectivity network maps based on graph theory. From this connectivity network, a series of connectivity metrics was obtained and used to feed a variety of classification algorithms. This process led to accuracies of 83% for a two-tasks classification problem and rose to a 93% averaged accuracy for a four-tasks problem

Towards a Personalized Multi-Domain Digital Neurophenotyping Model for the Detection and Treatment of Mood Trajectories

The commercial availability of many real-life smart sensors, wearables, and mobile apps provides a valuable source of information about a wide range of human behavioral, physiological, and social markers that can be used to infer the user’s mental state and mood. However, there are currently no commercial digital products that integrate these psychosocial metrics with the real-time measurement of neural activity. In particular, electroencephalography (EEG) is a well-validated and highly sensitive neuroimaging method that yields robust markers of mood and affective processing, and has been widely used in mental health research for decades. The integration of wearable neuro-sensors into existing multimodal sensor arrays could hold great promise for deep digital neurophenotyping in the detection and personalized treatment of mood disorders. In this paper, we propose a multi-domain digital neurophenotyping model based on the socioecological model of health. The proposed model presents a holistic approach to digital mental health, leveraging recent neuroscientific advances, and could deliver highly personalized diagnoses and treatments. The technological and ethical challenges of this model are discussed

Los ambientes lúdicos internos y su incidencia en el proceso de enseñanza aprendizaje de los niños de 1º. De Educación Inicial del centro infantil municipal María Olimpia Gudiño N1 en el año lectivo 2013-2014

Determinar el nivel de incidencia de los ambientes lúdicos, en el proceso de enseñanza aprendizaje de los niños de 3 a 4 años del Centro Infantil Municipal “María Olimpia Gudiño” Nro. 1, en el año lectivo 2013 - 2014.La investigación parte de la existencia del problema de ¿Cómo inciden los Ambientes Lúdicos en el Proceso de Enseñanza Aprendizaje de los niños de 3 a 4 años del Centro Infantil Municipal ¿María Olimpia Gudiño¿ Nº 1 en el año lectivo 2013- 2014. El objetivo de la investigación es determinar el nivel de incidencia de los ambientes lúdicos, en el proceso de enseñanza aprendizaje de estos niños. El campo de acción está determinado como los medios del proceso enseñanza aprendizaje. Por la modalidad de investigación corresponde a un proyecto Factible, donde el diseño metodológico que se escogió es una investigación documental, de campo y de tipo descriptivo y propositivo. Apoyada en el método analítico ¿ sintético, inductivo¿deductivo, los investigados fueron los docentes y niños quienes constituyeron la población y grupo de estudio. Pedagógicamente se sustenta en la Teoría Científica propuesta por Montessori, Psicológicamente se fundamenta en la Teoría cognitiva y la Teoría del Aprendizaje Significativo. Se ha analizado además la importancia de los Ambientes Lúdicos como un espacio relacional que constantemente propicia el diálogo entre sus miembros, a fin de transformar el rol pasivo del sujeto que aprende en sujeto protagonista de su propio desarrollo, donde el juego crea una zona de desarrollo potencial y cumple una función determinante en la formación del niño, de modo que el niño aprende a vivir mediante el juego, y, desde la interacción con los objetos y las personas que apoyan sus estructuras cognitivas y atienden necesidades sociales, emocionales e intelectuales. También se detalla las características, físicas, conductas motoras, destrezas, censo percepción, lenguaje y aspecto psicosocial del niño de 3 a 4 años. Se analiza además a la guía didáctica como un recurso que favorece los roles dinámicos de docentes y estudiantes en el proceso de aprendizaje.Licenciatur

“Análisis de la calidad del servicio posventa y la satisfacción de clientes de los concesionarios de la industria automotriz en Colombia”

El propósito del presente estudio es analizar la percepción de calidad del servicio de los concesionarios automotrices del país, identificando los factores que impactan en la satisfacción de los clientes y que son importantes en el mercado de los concesionarios. Como instrumento de medición se utilizó el modelo SERVPERF (Service Performance), escala propuesta por Cronin y Taylor (1992), reconocida por su validez, utilidad y eficiencia para medir la calidad del servicio en los negocios con la posibilidad de abarcar varios sectores y en este caso aplicada a los concesionarios con presencia a nivel nacional. Se realizó un muestreo no probabilístico por cuotas con los clientes de 2 concesionarios Chevrolet de Colombia, dando lugar a 139 encuestas individuales para el análisis, complementada con entrevistas a profundidad a clientes de concesionarios de otras marcas y a los Gerentes de Servicio Posventa. Se identificaron los factores que influyen en la satisfacción de los clientes de los concesionarios y el grado de complacencia, así como la relevancia de cada una de las dimensiones cumplir con las expectativas de los clientes. Finalmente, se resaltan las oportunidades de mejora para este mercado tan competitivo.Maestrí

Emotional valence modulates the topology of the parent-infant inter-brain network.

Emotional communication between parents and children is crucial during early life, yet little is known about its neural underpinnings. Here, we adopt a dual connectivity approach to assess how positive and negative emotions modulate the interpersonal neural network between infants and their mothers during naturalistic interaction. Fifteen mothers were asked to model positive and negative emotions toward pairs of objects during social interaction with their infants (mean age 10.3 months) whilst the neural activity of both mothers and infants was concurrently measured using dual electroencephalography (EEG). Intra-brain and inter-brain network connectivity in the 6-9 Hz range (i.e. infant Alpha band) during maternal expression of positive and negative emotions was computed using directed (partial directed coherence, PDC) and non-directed (phase-locking value, PLV) connectivity metrics. Graph theoretical measures were used to quantify differences in network topology as a function of emotional valence. We found that inter-brain network indices (Density, Strength and Divisibility) consistently revealed strong effects of emotional valence on the parent-child neural network. Parents and children showed stronger integration of their neural processes during maternal demonstrations of positive than negative emotions. Further, directed inter-brain metrics (PDC) indicated that mother to infant directional influences were stronger during the expression of positive than negative emotional states. These results suggest that the parent-infant inter-brain network is modulated by the emotional quality and tone of dyadic social interactions, and that inter-brain graph metrics may be successfully applied to examine these changes in parent-infant inter-brain network topology.UK Economic and Social Research Council (ESRC) Transforming Social Sciences Grant ES/N006461/1 (to V.L. and S.W.), a Nanyang Technological University start-up Grant M4081585.SS0 (to V.L.), a Ministry of Education (Singapore) Tier 1 grant M4012105.SS0 (V.L.) and an ESRC Future Research Leaders Fellowship ES/N017560/1 (to S.W.)

Green nanocomposites from Salvia-based waterborne polyurethane-urea dispersions reinforced with nanocellulose

Waterborne polyurethane-urea (WBPUU) dispersions, products having none or low contents of organic solvents, depending on the used synthesis process, can provide suitable environmentally-friendly strategies to prepare novel materials. Moreover, waterborne systems enable the incorporation of aqueous dispersible nanoentities and soluble additives, which provides a strategy to design versatile functional materials with tailored properties. Having demonstrated in previous work the bacteriostatic properties of a 3 wt% Salvia-based WBPUU against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, this work is focused in the preparation of Salvia-based WBPUU added with cellulose nanocrystals (CNC) tackling the preparation of functional green nanocomposite films with increased mechanical properties. Through this strategy, nanocomposites loaded with 1, 3 and 5 wt% of CNC were prepared, showing an effective CNC incorporation avoiding agglomerates. CNC addition is able to modulate soft and hard phase's segregation, inducing enhanced mechanical stiffness, together with improved deformability, while retarding thermomechanical instability to higher temperatures.Financial support from the University of the Basque Country (UPV/ EHU) (GIU18/216 Research Group), the Spanish Ministry of Economy and Competitiveness (MINECO) (MAT2016-76294-R). Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020). National funding by FCT- Foundation for Science and Technology, through the institutional scientific employment program-contract with I.P. Fernandes. We also wish to acknowledge the “Macrobehaviour-Mesostructure- Nanotechnology” SGIker units from the UPV/EHU, for their technical supporinfo:eu-repo/semantics/publishedVersio

Apalancamiento financiero y la rentabilidad de la empresa Industrias del papel S.A. Periodos 2016 -2020

En el presente artículo de investigación tuvo como propósito determinar la relación de los indicadores de apalancamiento financiero y la rentabilidad de la empresa Industrias del Papel S.A. periodos 2016 – 2020, así mismo la metodología de investigación responde al diseño no experimental de enfoque transversal, de tipo cuantitativo, de alcance descriptivo, correlacional, la población está constituida por los estados financieros de la empresa Industrias del Papel, como muestra se analizara de manera trimestral de los años 2016 -2020, se consideró el análisis con el coeficiente rho de spearman por tener datos no normales, por lo cual se evidenció a manera de conclusión se identificó una relación inversa entre los ratios de apalancamiento financiero frente a los indicadores de la rentabilidad, evidenciando que mientras el apalancamiento financiero aumente la otra variable disminuye, provocando una efecto contrario, por lo que se aceptó la hipótesis alterna de la investigación.LIMAEscuela Profesional de ContabilidadFinanza

Effects of targeted memory reactivation on cortical networks

Sleep is a complex physiological process with an important role in memory consolidation characterised by a series of spatiotemporal changes in brain activity and connectivity. Here, we investigate how task-related responses differ between pre-sleep wake, sleep, and post-sleep wake. To this end, we trained participants on a serial reaction time task using both right and left hands using Targeted Memory Reactivation (TMR), in which auditory cues are associated with learned material and then re-presented in subsequent wake or sleep periods in order to elicit memory reactivation. The neural responses just after each cue showed increased theta band connectivity between frontal and other cortical regions, as well as between hemispheres, in slow wave sleep compared to pre- or post-sleep wake. This pattern was consistent across the cues associated with both right- and left-handed movements. We also searched for hand-specific connectivity and found that this could be identified in within-hemisphere connectivity after TMR cues during sleep and post-sleep sessions. The fact that we could identify which hand had been cued during sleep suggests that these connectivity measures could potentially be used to determine how successfully memory is reactivated by our manipulation. Collectively, these findings indicate that TMR modulates the brain cortical networks showing clear differences between wake and sleep connectivity patterns