Estimulación del nervio vago para el tratamiento de la epilepsia refractaria al tratamiento médico en el Hospital Universitario de Canarias.

Alrededor de un 30% de los pacientes que sufren epilepsia presentan resistencia al tratamiento farmacológico. En el Hospital Universitario de Canarias (HUC) existe la unidad médico-quirúrgica de epilepsia refractaria, que actúa como referencia para tratar estos casos en la Comunidad Autónoma. El tratamiento quirúrgico de elección se basa en la resección del foco epileptógeno; sin embargo, un elevado número de pacientes no presenta un foco claro (origen multifocal) o lo presenta en una zona elocuente del cerebro (regiones irresecables). Estos pacientes son candidatos a la implantación de un estimulador del nervio vago (ENV), terapia neuroquirúrgica aprobada por la FDA en 1997 y realizada en el HUC desde el año 2007. El propósito de este Trabajo de Fin de Grado es analizar los resultados de la implantación del estimulador del nervio vago (efectividad, complicaciones…) en pacientes que han sido sometidos a dicha intervención por parte del Servicio de Neurocirugía del HUC. Para ello, se va a extraer información de las historias clínicas de los pacientes a partir de una base de datos electrónica codificada en números de historia de los mismos. El modelo del estudio es observacional retrospectivo y no se realizará ninguna intervención diagnósticoterapéutica como parte de este. Se incluirán todos los pacientes intervenidos por el Servicio de Neurocirugía del HUC desde el año 2007, independientemente de su edad y sexo, siendo excluidos aquellos en los que conste una objeción a participar en proyectos de investigación. Con esta información se crearán grupos de respuesta al ENV que nos permitirá hacer un estudio por separado y comparativo entre dichos grupos.About 30% of patients that suffer from epilepsy show resistance to pharmacological treatment. In the Hospital Universitario de Canarias (HUC) there is a medical-surgical unit for refractory epilepsy, which acts as a reference to treat these cases in the Autonomous Community. The elegible surgical treatment is based on resection of the epileptogenic focus; however, a large number of patients do not have a clear focus (multifocal origin) or it is presented in an eloquent area of the brain (unresectable regions). These patients are candidates for implantation of a vagus nerve stimulator (VNS), neurosurgical therapy approved by the FDA in 1997 and performed at the HUC since 2007. The purpose of this Final Degree Project is to analyze the results of the implantation of the vagus nerve stimulator (effectiveness, complications ...) in patients who have undergone such intervention by the HUC Neurosurgery Service. For this, information will be extracted from the patient's medical records, from an electronic database encoded in patient’s history numbers. The study model is retrospective observational and no diagnostic-therapeutic interventions will be performed as part of it. All patients operated on by the HUC Neurosurgery Service since 2007, regardless of their age and sex, will be included, excluding those with an objection to participating in research projects. With this information, VNS response groups will be created to make a separated and comparative study between these groups

Retraction: time series decomposition using automatic learning techniques for predictive models

This article, and others within this volume, has been retracted by IOP Publishing following clear evidence of plagiarism and citation manipulation. This work was originally published in Spanish (1) and has been translated and published without permission or acknowledgement to the original authors. IOP Publishing Limited has discovered other papers within this volume that have been subjected to the same treatment. This is scientific misconduct. Misconduct investigations are ongoing at the author's institutions. IOP Publishing Limited will update this notice if required once those investigations have concluded. To date, there is no evidence to suggest anyone other than Amelec Viloria / Jesus Silva was directly culpable for the actions that led to retraction

Parallel Algorithm for Reduction of Data Processing Time in Big Data

Technological advances have allowed to collect and store large volumes of data over the years. Besides, it is significant that today's applications have high performance and can analyze these large datasets effectively. Today, it remains a challenge for data mining to make its algorithms and applications equally efficient in the need of increasing data size and dimensionality [1]. To achieve this goal, many applications rely on parallelism, because it is an area that allows the reduction of cost depending on the execution time of the algorithms because it takes advantage of the characteristics of current computer architectures to run several processes concurrently [2]. This paper proposes a parallel version of the FuzzyPred algorithm based on the amount of data that can be processed within each of the processing threads, synchronously and independently

Análisis de Correspondencias Múltiples en donantes de sangre de la Cruz Roja Ecuatoriana Junta Provincial de Chimborazo, periodo 2017-2020

El presente trabajo de titulación tuvo como objetivo estudiar la interdependencia entre las variables demográficas en donantes de sangre de la Cruz Roja Ecuatoriana Junta Provincial de Chimborazo durante el periodo 2017 – 2020, a través de la aplicación de técnicas estadísticas. La matriz de información se tomó del software de registro de donantes de sangre e-Delphyn, donde se almacena la información recolectada en campañas de donación de sangre. Para el estudio se consideraron las variables: sexo, edad, población, nuevo donante, tipo de donación, grupo sanguíneo, aceptación de la donación. Se realizó un análisis descriptivo a cada variable en estudio para observar el comportamiento de los datos, seguidamente se aplicó un análisis de correlación para verificar la relación existente entre pares de variables, luego se realizó un análisis de independencia para observar si existe relación o no entre las variables objeto de estudio, por último se aplicó un análisis de correspondencias múltiples con el objetivo de representar en un espacio multidimensional reducido la relación existente entre las categorías de las variables cualitativas propuestas en el presente estudio. Se obtuvo como resultados que solo las variables edad y donante nuevo presentaron una relación lineal relativamente débil, inversamente proporcional; la prueba de hipótesis chi-cuadrado de independencia identificó que los pares de variables tipo de donación y sexo, tipo de donación y población, aceptación sanguínea y población, fueron independientes entre sí; la aplicación del análisis de correspondencias múltiples a través del mapa perceptual no generó resultados óptimos para el estudio ya que, el porcentaje de variabilidad de las dos primeras coordenadas principales fue del 10.71%. Se concluye que las variables sexo, población, edad y nuevo donante, aportaron de manera significativa a la donación de sangre. Se recomienda aplicar técnicas multivariadas en futuras investigaciones para contribuir en la toma de decisiones.The objective of this work was to study the interdependence between demographic variables in blood donors at Cruz Roja Ecuatoriana Junta Provincial de Chimborazo during 2017-2020, through the application of statistical techniques. The information matrix was taken from the e-Delphyn blood donor registry software, where the information collected in blood donation campaigns is stored. For the study, the considered variables were: sex, age, population, new donor, type of donation, blood group, acceptance of the donation. A descriptive analysis was carried out on each variable under study to observe the behavior of the data, then a correlation analysis was applied to verify the existing relationship between pairs of variables. After that an independence analysis was performed to observe whether or not there is a relationship between the variables under study. Finally, a multiple correspondence analysis was applied in order to represent in a reduced multidimensional space the relationship between the categories of the qualitative variables proposed in the present study. The results were that only the variables age and new donor presented a relatively weak linear relationship, inversely proportional. The chi-square hypothesis test of independence identified that the pairs of variables type of donation and sex, type of donation and population, blood acceptance and population, were independent of each other; The application of multiple correspondence analysis through the perceptual map did not generate optimal results for the study, since the percentage of variability of the first two main coordinates was 10.71%. It is concluded that the variables sex, population, age and new donor contributed significantly to blood donation. It is recommended to apply multivariate techniques in future research to contribute to decision making

High On/Off ratio memristive switching of manganite/cuprate bilayer by interfacial magnetoelectricity

Memristive switching serves as the basis for a new generation of electronic devices. Memristors are two-terminal devices in which the current is turned on and off by redistributing point defects, e.g., vacancies, which is difficult to control. Memristors based on alternative mechanisms have been explored, but achieving both the high On/Off ratio and the low switching energy desirable for use in electronics remains a challenge. Here we report memristive switching in a La_(0.7)Ca_(0.3)MnO_(3)/PrBa_(2)Cu_(3)O_(7) bilayer with an On/Off ratio greater than 103 and demonstrate that the phenomenon originates from a new type of interfacial magnetoelectricity. Using results from firstprinciples calculations, we show that an external electric-field induces subtle displacements of the interfacial Mn ions, which switches on/off an interfacial magnetic “dead” layer, resulting in memristive behavior for spin-polarized electron transport across the bilayer. The interfacial nature of the switching entails low energy cost about of a tenth of atto Joule for write/erase a “bit”. Our results indicate new opportunities for manganite/cuprate systems and other transition-metal-oxide junctions in memristive applications

Interfacial-Redox-Induced Tuning of Superconductivity in YBa2Cu3O7-δ.

Solid-state ionic approaches for modifying ion distributions in getter/oxide heterostructures offer exciting potentials to control material properties. Here, we report a simple, scalable approach allowing for manipulation of the superconducting transition in optimally doped YBa2Cu3O7-δ (YBCO) films via a chemically driven ionic migration mechanism. Using a thin Gd capping layer of up to 20 nm deposited onto 100 nm thick epitaxial YBCO films, oxygen is found to leach from deep within the YBCO. Progressive reduction of the superconducting transition is observed, with complete suppression possible for a sufficiently thick Gd layer. These effects arise from the combined impact of redox-driven electron doping and modification of the YBCO microstructure due to oxygen migration and depletion. This work demonstrates an effective step toward total ionic tuning of superconductivity in oxides, an interface-induced effect that goes well into the quasi-bulk regime, opening-up possibilities for electric field manipulation

Electrical properties of biomorphic SiC ceramics and SiC/Si composites fabricated from medium density fiberboard

A study has been made of the dependences of the electrical resistivity and the Hall coefficient on the temperature in the range 1.8–1300 K and on magnetic fields of up to 28 kOe for the biomorphic SiC/Si (MDF-SiC/Si) composite and biomorphic porous SiC (MDF-SiC) based upon artificial cellulosic precursor (MDF – medium density fiberboards). It has been shown that electric transport in MDF-SiC is effected by carriers of n-type with a high concentration of ∼1020 cm−3 and a low mobility of ∼0.4 cm2 V−1 s−1. The specific features in the conductivity of MDF-SiC are explained by quantum effects arising in disordered systems and requiring quantum corrections to conductivity. The TEM studies confirmed the presence of disordering structural features (nanocrystalline regions) in MDF-SiC. The conductivity of MDF-SiC/Si composite originates primarily from Si component in the temperature range 1.8–500 K and since ∼500 to 600 K the contribution of MDF-SiC matrix becomes dominant

Exfoliation of Alpha-Germanium: A Covalent Diamond-Like Structure

2D materials have opened a new field in materials science with outstanding scientific and technological impact. A largely explored route for the preparation of 2D materials is the exfoliation of layered crystals with weak forces between their layers. However, its application to covalent crystals remains elusive. Herein, a further step is taken by introducing the exfoliation of germanium, a narrow-bandgap semiconductor presenting a 3D diamond-like structure with strong covalent bonds. Pure α-germanium is exfoliated following a simple one-step procedure assisted by wet ball-milling, allowing gram-scale fabrication of high-quality layers with large lateral dimensions and nanometer thicknesses. The generated flakes are thoroughly characterized by different techniques, giving evidence that the new 2D material exhibits bandgaps that depend on both the crystallographic direction and the number of layers. Besides potential technological applications, this work is also of interest for the search of 2D materials with new properties

O plano nacional de desenvolvimento de 2018-2022, “Pacto pela Colômbia, Pacto pela Equidade”. Reflexões e propostas

The Colombian government presented to Congress, the National Development Plan (PND) 2018-2022 “Pact for Colombia, Pact for Equity,” which was approved by Law 1955 of 2019. The reflections and proposals included in this paper refer to the main components of the PND, the reforms proposed, the Multi-Annual Program of Investments that accompanies it, as well as to its apparent omissions. The paper does not intend to cover all the topics in the PND.El gobierno colombiano presentó al Congreso el Plan Nacional de Desarrollo (PND) 2018-2022 “Pacto por Colombia, Pacto por la Equidad,” que fue aprobado mediante la Ley 1955 de 2019. Las reflexiones y propuestas incluidas en este artículo se refieren a los componentes principales del PND, a las reformas que implican, al Programa Plurianual de Inversiones que lo acompaña y a sus omisiones aparentes, sin la pretensión de agotar todos los temas.O governo colombiano apresentou ao Congresso o Plano Nacional de Desenvolvimento (PND) 2018-2022 “Pacto para a Colômbia, Pacto pela Equidade”, que foi aprovado pela Lei 1955 de 2019. As reflexões e propostas incluídas neste artigo referem-se à principais componentes do PND, as reformas que implicam, o Programa Plurianual de Investimentos que o acompanha e suas aparentes omissões, sem pretender esgotar todas as questões

Modified magnetic anisotropy at LaCoO_(3)/La_(0.7)Sr_(0.3)MnO_(3) interfaces

Controlling magnetic anisotropy is an important objective towards engineering novel magnetic device concepts in oxide electronics. In thin film manganites, magnetic anisotropy is weak and it is primarily determined by the substrate, through induced structural distortions resulting from epitaxial mismatch strain. On the other hand, in cobaltites, with a stronger spin orbit interaction, magnetic anisotropy is typically much stronger. In this paper, we show that interfacing La0.7Sr0.3MnO3 (LSMO) with an ultrathin LaCoO3 (LCO) layer drastically modifies the magnetic anisotropy of the manganite, making it independent of the substrate and closer to the magnetic isotropy characterizing its rhombohedral structure. Ferromagnetic resonance measurements evidence a tendency of manganite magnetic moments to point out-of-plane suggesting non collinear magnetic interactions at the interface. These results may be of interest for the design of oxide interfaces with tailored magnetic structures for new oxide devices