On multifractals: a non-linear study of actigraphy data

This work aimed, to determine the characteristics of activity series from fractal geometry concepts application, in addition to evaluate the possibility of identifying individuals with fibromyalgia. Activity level data were collected from 27 healthy subjects and 27 fibromyalgia patients, with the use of clock-like devices equipped with accelerometers, for about four weeks, all day long. The activity series were evaluated through fractal and multifractal methods. Hurst exponent analysis exhibited values according to other studies ($H>0.5$) for both groups ($H=0.98\pm0.04$ for healthy subjects and $H=0.97\pm0.03$ for fibromyalgia patients), however, it is not possible to distinguish between the two groups by such analysis. Activity time series also exhibited a multifractal pattern. A paired analysis of the spectra indices for the sleep and awake states revealed differences between healthy subjects and fibromyalgia patients. The individuals feature differences between awake and sleep states, having statistically significant differences for $\alpha_{q-} - \alpha_{0}$ in healthy subjects ($p = 0.014$) and $D_{0}$ for patients with fibromyalgia ($p = 0.013$). The approach has proven to be an option on the characterisation of such kind of signals and was able to differ between both healthy and fibromyalgia groups. This outcome suggests changes in the physiologic mechanisms of movement control.Comment: Preprint accepted for publication at Physica A: Statistical Mechanics and its Application

La empresa informativa busca nuevos modelos de negocio

Old business model traditionally used in media, based on reader or consumer collection and advertising revenue is insufficient to sustain media companies. It is necessary to reinvent this business model to allow media survive in our new online multi-product and globalized media market.El modelo de negocio tradicionalmente empleado en los medios informativos, basado en el cobro al lector o consumidor y en los ingresos publicitarios, resulta insuficiente para poder sostener la empresa informativa. Es necesario reinventar el modelo de negocio, buscando un sistema que permita a los medios subsistir en el nuevo mercado mediático online, con multiproducto y globalizado

Self-Regulation of SMR Power Led to an Enhancement of Functional Connectivity of Somatomotor Cortices in Fibromyalgia Patients

Neuroimaging studies have demonstrated that altered activity in somatosensory and motor cortices play a key role in pain chronification. Neurofeedback training of sensorimotor rhythm (SMR) is a tool which allow individuals to self-modulate their brain activity and to produce significant changes over somatomotor brain areas. Several studies have further shown that neurofeedback training may reduce pain and other pain-related symptoms in chronic pain patients. The goal of the present study was to analyze changes in SMR power and brain functional connectivity of the somatosensory and motor cortices elicited by neurofeedback task designed to both synchronize and desynchronize the SMR power over motor and somatosensory areas in fibromyalgia patients. Seventeen patients were randomly assigned to the SMR training (n = 9) or to a sham protocol (n = 8). All participants were trained during 6 sessions, and fMRI and EEG power elicited by synchronization and desynchronization trials were analyzed. In the SMR training group, four patients achieved the objective of SMR modulation in more than 70% of the trials from the second training session (good responders), while five patients performed the task at the chance level (bad responders). Good responders to the neurofeedback training significantly reduced pain and increased both SMR power modulationandfunctionalconnectivityofmotorandsomatosensoryrelatedareasduring the last neurofeedback training session, whereas no changes in brain activity or pain were observed in bad responders or participants in the sham group. In addition, we observed that good responders were characterized by reduced impact of fibromyalgia and pain symptoms, as well as by increased levels of health-related quality of life during the pre-training sessions. In summary, the present study revealed that neurofeedback training of SMR elicited significant brain changes in somatomotor areas leading to a significant reduction of pain in fibromyalgia patients. In this sense, our research provide evidence that neurofeedback training is a promising tool for a better understanding of brain mechanisms involved in pain chronification

Estimación visual de las pérdidas sanguíneas por el personal de anestesiología de dos hospitales universitarios

Existe un gran vacío en la literatura sobre el cómo se cuantifica el sangrado peroperatorio y cuál es la importancia real de este factor a la hora de definir la necesidad de una transfusión, Lo que nos proponemos es identificar cuan precisa es ésta habilidad entre los anestesiólogos y residentes de anestesiología de nuestro medio y, evaluar cuáles son los factores afectan la estimación del sangrado intraoperatorio entre éstos profesionales mediante un estudio descriptivo donde se comparará los valores de sangre calculados por los anestesiólogos y residentes de anestesiología del HUCS (hospital universitario clínica san Rafael) y el HOMIC ( hospital militar central) que se encuentran contenidos en diferentes medios absorbentes y contenedores volumétricos y los valores reales conocidos gracias al diseño del estudi

Estimación visual de las pérdidas sanguíneas por el personal de anestesiología de dos hospitales universitarios

Existe un gran vacío en la literatura sobre el cómo se cuantifica el sangrado peroperatorio y cuál es la importancia real de este factor a la hora de definir la necesidad de una transfusión, Lo que nos proponemos es identificar cuan precisa es ésta habilidad entre los anestesiólogos y residentes de anestesiología de nuestro medio y, evaluar cuáles son los factores afectan la estimación del sangrado intraoperatorio entre éstos profesionales mediante un estudio descriptivo donde se comparará los valores de sangre calculados por los anestesiólogos y residentes de anestesiología del HUCS (hospital universitario clínica san Rafael) y el HOMIC ( hospital militar central) que se encuentran contenidos en diferentes medios absorbentes y contenedores volumétricos y los valores reales conocidos gracias al diseño del estudi

Communicative Change in the New Didactic Methodologies

El acto comunicativo clásicamente entendido, informativo o docente, se compone de un emisor, un receptor, un referente y un canal por el que se transmite el mensaje cifrado en un código (Jakobson, 1963). Hemos realizado una revisión de las diferentes metodologías didácticas que se están desarrollando en la actualidad, tanto en áreas de ciencias como de letras. De esta revisión podemos concluir que la metodología tradicional es la más empleada hoy que sigue los principios del acto comunicativo tradicional, el profesor es el emisor, el alumno es el receptor y el mensaje es la explicación del profesor. Sin embargo, se puede también concluir que las nuevas metodologías hacen que el alumno asuma el papel activo, como actor principal del proceso de enseñanza y aprendizaje.The communicative classically understood, informative or educational act, consists of an issuer, a recipient, a modal and a channel by which there is transmitted the message coded in a code (Jakobson, 1963). We have realized a review of the different didactic methodologies that are developing at present, so much in areas of sciences as of letters. Of this review we can conclude that the traditional methodology is most used today and it follows the communicative traditional act, the teacher is the issuer, the student is the recipient and the message is the explanation of the teacher. Nevertheless, it is possible conclude also that the new methodologies do that the student assumes the active role, as principal actor of the process of education and learning

An Alternate Representation of the Vector of Apparent Power and Unbalanced Power in Three-Phase Electrical Systems

[EN] Low-voltage distribution systems are typically unbalanced. These ine¿ciencies cause unbalanced powers that can significantly increase the apparent power of the system. Analysing and measuring these ine¿cient powers appropriately allows us to compensate for them and obtain a more e¿cient system. Correcting the imbalance at some nodes can worsen the rest of the system; therefore, it is essential that all nodes are analysed such that action can be taken when necessary. In most studies, the unbalanced power is measured from the modulus. Other more recent studies have proposed phasor expressions of unbalanced powers; however, in both cases, these are not enough to address the compensation of unbalanced powers in systems with unbalanced voltages. In this work, a di¿erent representation of the vector expressions for analysis of the unbalanced powers and the apparent powers of the three-phase linear systems is proposed. Additionally, these vector expressions are extended to nonlinear systems to quantify the harmonic apparent powers. These expressions have been formulated from the power of Buchholz and are valid for systems with unbalanced voltages and currents. To help understand the use of the proposed formulation, a practical case of a three-phase four-wire system with unbalanced loads and voltages is demonstrated.This work is supported by the Spanish Ministry of Science, Innovation and Universities (MICINN) and the European Regional Development Fund (ERDF) under Grant RTI2018-100732-B-C21.Blasco Espinosa, PA.; Montoya-Mira, R.; Diez-Aznar, J.; Montoya Villena, R. (2020). An Alternate Representation of the Vector of Apparent Power and Unbalanced Power in Three-Phase Electrical Systems. Applied Sciences. 10(11):1-16. https://doi.org/10.3390/app10113756S1161011Emanuel, A. E. (1993). On the definition of power factor and apparent power in unbalanced polyphase circuits with sinusoidal voltage and currents. IEEE Transactions on Power Delivery, 8(3), 841-852. doi:10.1109/61.252612Willems, J. L. (2004). Reflections on Apparent Power and Power Factor in Nonsinusoidal and Polyphase Situations. IEEE Transactions on Power Delivery, 19(2), 835-840. doi:10.1109/tpwrd.2003.823182Emanuel, A. E. (1999). Apparent power definitions for three-phase systems. IEEE Transactions on Power Delivery, 14(3), 767-772. doi:10.1109/61.772313Czarnecki, L. S. (1994). Misinterpretations of some power properties of electric circuits. IEEE Transactions on Power Delivery, 9(4), 1760-1769. doi:10.1109/61.329509Kersting, W. H. (2001). Causes and effects of unbalanced voltages serving an induction motor. IEEE Transactions on Industry Applications, 37(1), 165-170. doi:10.1109/28.903142Pillay, P., & Manyage, M. (2006). Loss of Life in Induction Machines Operating With Unbalanced Supplies. IEEE Transactions on Energy Conversion, 21(4), 813-822. doi:10.1109/tec.2005.853724Poblador, M. L. A., & Lopez, G. A. R. (2013). Power calculations in nonlinear and unbalanced conditions according to IEEE Std 1459-2010. 2013 Workshop on Power Electronics and Power Quality Applications (PEPQA). doi:10.1109/pepqa.2013.6614957Langella, R., Testa, A., & Emanuel, A. E. (2012). Unbalance Definition for Electrical Power Systems in the Presence of Harmonics and Interharmonics. IEEE Transactions on Instrumentation and Measurement, 61(10), 2622-2631. doi:10.1109/tim.2012.2209909Kukačka, L., Kraus, J., Kolář, M., Dupuis, P., & Zissis, G. (2016). Review of AC power theories under stationary and non‐stationary, clean and distorted conditions. IET Generation, Transmission & Distribution, 10(1), 221-231. doi:10.1049/iet-gtd.2015.0713Chicco, G., Postolache, P., & Toader, C. (2007). Analysis of Three-Phase Systems With Neutral Under Distorted and Unbalanced Conditions in the Symmetrical Component-Based Framework. IEEE Transactions on Power Delivery, 22(1), 674-683. doi:10.1109/tpwrd.2006.887095Paap, G. C. (2000). Symmetrical components in the time domain and their application to power network calculations. IEEE Transactions on Power Systems, 15(2), 522-528. doi:10.1109/59.867135León-Martínez, V., & Montañana-Romeu, J. (2018). Formulations for the apparent and unbalanced power vectors in three-phase sinusoidal systems. Electric Power Systems Research, 160, 37-43. doi:10.1016/j.epsr.2018.01.028Castilla, M., Bravo, J. C., Ordonez, M., & Montano, J. C. (2008). Clifford Theory: A Geometrical Interpretation of Multivectorial Apparent Power. IEEE Transactions on Circuits and Systems I: Regular Papers, 55(10), 3358-3367. doi:10.1109/tcsi.2008.924885Diez, J. M., Blasco, P. A., & Montoya, R. (2016). Formulation of phasor unbalance power: application to sinusoidal power systems. IET Generation, Transmission & Distribution, 10(16), 4178-4186. doi:10.1049/iet-gtd.2016.0730Tongxin Zheng, Makram, E. B., & Girgis, A. A. (2003). Evaluating power system unbalance in the presence of harmonic distortion. IEEE Transactions on Power Delivery, 18(2), 393-397. doi:10.1109/tpwrd.2002.807460Mohamadian, S., & Shoulaie, A. (2011). Comprehensive Definitions for Evaluating Harmonic Distortion and Unbalanced Conditions in Three- and Four-Wire Three-Phase Systems Based on IEEE Standard 1459. IEEE Transactions on Power Delivery, 26(3), 1774-1782. doi:10.1109/tpwrd.2011.2126609Blasco, P. A., Montoya-Mira, R., Diez, J. M., Montoya, R., & Reig, M. J. (2019). Compensation of Reactive Power and Unbalanced Power in Three-Phase Three-Wire Systems Connected to an Infinite Power Network. Applied Sciences, 10(1), 113. doi:10.3390/app10010113Montoya-Mira, R., Blasco, P. A., Diez, J. M., Montoya, R., & Reig, M. J. 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VERITAS long term monitoring of Gamma-Ray emission from the BL Lacertae object

BL Lacertae is the prototype of the blazar subclass known as BL Lac type objects. BL Lacertae object itself is a low-frequency-peaked BL Lac(LBL). Very high energy (VHE) gamma ray emission from this source was discovered in 2005 by MAGIC observatory while the source was at a flaring state. Since then, VHE gamma rays from this source has been detected several times. However, all of those times the source was in a high activity state. Former studies suggest several non-thermal zones emitting in gamma-rays, then gamma-ray flare should be composed of a convolution. Observing the BL Lacertae object at quiescent states and active states is the key to disentangle these two components. VERITAS is monitoring the BL Lacertae object since 2011. The archival data set includes observations during flaring and quiescent states. This presentation reports on the preliminary results of the VERITAS observation between January 2013 - December 2015, and simultaneous multiwavelength observations