Characterization of Neural Activity using Complex Network Theory. Application to the Identification of the Altered Neural Substrates in Schizophrenia

La esquizofrenia es un desorden psiquiátrico caracterizado por alteraciones en el pensamiento y en la capacidad de respuesta emocional. Comprende una gran variedad de síntomas, sin embargo, no está claro que todos compartan un sustrato neurológico común. Por ello, el objetivo de esta Tesis Doctoral es desarrollar un marco de referencia desde la perspectiva de la Teoría de Redes Complejas para investigar las interacciones neurales alteradas de la esquizofrenia haciendo uso de la señal electroencefalográfica. Así, dos bases de datos independientes de registros electroencefalográficos fueron registras durante una tarea cognitiva. Nuestros hallazgos son consistentes con estudios previos al tiempo que muestran una hiperactivación del intervalo de estímulo previa a una reorganización neural disminuida durante la cognición, principalmente asociado a caminos neurales secundarios. Los hallazgos de esta Tesis ponen de manifiesto la gran heterogeneidad de la esquizofrenia, posiblemente asociada a la existencia de subgrupos dentro de la misma.Departamento de Teoría de la Señal y Comunicaciones e Ingeniería TelemáticaDoctorado en Tecnologías de la Información y las Telecomunicacione

Optical instrument for the study of time recovery from total disability glare vision

Disability glare is defined as the loss of contrast sensitivity of the retinal image due to intraocular straylight originated from the presence of an intense and broad bright light in the field of vision. This loss of vision can range between vision loss at high spatial frequencies or total temporal blindness. If the extreme case occurs, the recovery time is crucial in night driving conditions or those professional activities in which maximum visual acuity is required at any moment. The recovery time depends mainly on the intensity and glare angle of the light source, ocular straylight, and the photoreceptor response at the retina. The recovery time can also be affected by ocular pathologies, aging, or physiological factors that increase ocular straylight. The aim of this work is to develop a new optical instrument based on psychophysical methodology as well as to investigate the recovery time from total disability glare (photobleaching) as a function of the contrast of the visual target and the glare angle of the source in healthy volunteers. Results showed significant exponential correlation between recovery time and contrast of the visual target and linear correlation between contrast sensitivity and the glare angle. Those findings allowed to obtain an empirical expression to compute the recovery time required to restore contrast sensitivity baseline vision after photobleaching. Finally, a statistical dependence of recovery time with age was found for short glare angles that disappear as the glare angle increases

Extracción y clasificación de características del electrocardiograma y la variabilidad del ritmo cardiaco. Aplicación al síndrome de la apnea-hipopnea del sueño

El propósito de este TFM es evaluar la utilidad del análisi automático de la señal de variabilidad del ritmo cardiaco (HRV) procedente del electrocardiograma (ECG)como posible alternativa a la polisomnografía (PSG) para ayudar al diagnóstico del Síndrome de Apnea-Hipopnea del Sueño (SAHS). Para ello, se dispuso de 240 registros de ECG procedentes de sujetos sospechosos de padecer SAHS. Estos registros fueron procesados mediante técnicas de análisis espectral y no lineal para la extracción de características. Posteriormente, se realizó una selección de dichas características mediante regresión logística paso a paso para, finalmente, realizar una clasificación basada en máquinas de soporte vectorial (SVM). Los sujetos fueron divididos en dos grupos: entrenamiento (sobre los que se extrajeron una serie de umbrales óptimos de decisión diagnóstica) y test (con lo que se midió el rendimiento diagnóstico). Dicho rendimiento fue expresado en términos de sensibilidad, especificidad, precisión y área bajo la curva ROC (AROC).Teoría de la Señal y Comunicaciones e Ingenieria TelemáticaMáster en Investigación en Tecnologías de la Información y las Comunicacione

Self-reported drug allergies and the diagnostic work-up in the surgical population

Producción CientíficaObjective The diagnostic work-up of a drug hypersensitivity reaction is indeed difficult. In general, medical documentation of allergic reactions in medical reports is usually highly deficient or non-existent. The aim of this study was to analyse the prevalence of selfreported drug allergies in the surgical population as well as the criteria used in the diagnosis of drug hypersensitivity reactions. Methods A prospective study with the consecutive participation of 1439 patients, following surgical intervention, attended the Post-Operative Care Unit. Previously, as a routine process during the pre-anesthesia consultation, all patients were questioned about whether they had any drug allergies to report and diagnostic work-up. Results The prevalence of self-reported drug allergies was 8.3% (119/1439): 3.6% considered themselves allergic to b-lactams and 2.4% to non-steroidal anti-inflammatory drugs. Approximately one-third of the subjects (40 out of the 119) had not been subjected to any allergy diagnostic procedure and with 79 (66.4%), the only diagnostic test used by the Allergy Unit had been the skin prick-test. None of those participating in the study had tryptase, methylhistamine, specific IgE or intradermal tests carried out to characterize the diagnosis of the allergic reaction. Conclusions These results show that self-reported drug allergies are highly prevalent and as yet little explored. It is an important prevalence which should bring about modifications to the prescription of certain medicaments. The medical personnel must be made aware of the need to make an accurate diagnosis of allergies to medicaments

An Asynchronous P300-Based Brain-Computer Interface Web Browser for Severely Disabled People

This paper presents an electroencephalo- graphic (EEG) P300-based brain–computer interface (BCI) Internet browser. The system uses the “odd-ball” row-col paradigm for generating the P300 evoked potentials on the scalp of the user, which are immediately processed and translated into web browser commands. There were previous approaches for controlling a BCI web browser. However, to the best of our knowledge, none of them was focused on an assistive context, failing to test their applications with a suitable number of end users. In addition, all of them were synchronous applications, where it was necessary to introduce a “read-mode” command in order to avoid a continuous command selection. Thus, the aim of this study is twofold: 1) to test our web browser with a population of multiple sclerosis (MS) patients in order to assess the usefulness of our proposal to meet their daily communication needs; and 2) to overcome the aforementioned limitation by adding a threshold that discerns between control and non-control states, allowing the user to calmly read the web page without undesirable selections. The browser was tested with sixteen MS patients and five healthy volunteers. Both quantitative and qualitative metrics were obtained. MS participants reached an average accuracy of 84.14%, whereas 95.75% was achieved by control subjects. Results show that MS patients can successfully control the BCI web browser, improving their personal autonom

Preliminary study on the performance of biomorphic silicon carbide as substrate for diesel particulate filters

This paper presents the results of a preliminary experimental study to assess the performance of biomorphic silicon carbide when used for the abatement of soot particles in the exhaust of Diesel engines. Given its optimal thermal and mechanical properties, silicon carbide is one of the most popular substrates in commercial diesel particulate filters. Biomorphic silicon carbide is known for having, besides, a hierarchical porous microstructure and the possibility of tailoring that microstructure through the selection of a suitable wood precursor. An experimental rig was designed and built to be integrated within an engine test bench that allowed to characterizing small lab-scale biomorphic silicon carbide filter samples. A particle counter was used to measure the particles distribution before and after the samples, while a differential pressure sensor was used to measure their pressure drop during the soot loading process. The experimental campaign yielded promising results: for the flow rate conditions that the measuring devices imposed (1 litre per minute; space velocity = 42,000 L/h), the samples showed initial efficiencies above 80%, pressure drops below 20 mbar, and a low increase in the pressure drop with the soot load which allows to reach almost 100% efficiency with an increase in pressure drop lower than 15%, when the soot load is still less than 0.01 g/L. It shows the potential of this material and the interest for advancing in more complex diesel particle filter designs based on the results of this workMinisterio de Economía y Competitividad (España) MAT2013-41233-R DPI2013-46485-C3-3-RFondos FEDER MAT2013-41233-R DPI2013-46485-C3-3-RUniversidad de Sevilla VI Plan Propio I.3B - C.I. 24/05/2017 MAT2016-76526-

Planteamiento de una metodología de mejora continua en la Tutorización y elaboración de Trabajos Fin de Grado

Fac. de Comercio y TurismoFALSEsubmitte

Insatisfacción y distorsión de la imagen corporal en adolescentes de doce a diecisiete años de edad

La presente investigación ha analizado la satisfacción con la apariencia física y el nivel de distorsión entre la imagen real y la imagen autoconcebida. Para ello se ha administrado el cuestionario BODY SHAPE (self-perceived) a 195 alumnos con edades comprendidas entre los doce y los diecisiete años, recogiendo además sus datos de peso y talla reales. Los resultados alcanzados reflejan que los hombres se encuentran más insatisfechos en este sentido, teniendo además una mayor distorsión de su imagen que las mujeres. Del mismo modo, a medida que aumenta la edad se observa una disminución de la distorsión, así como un aumento de los niveles de satisfacción. No obstante, los valores son alarmantes por lo que toda la comunidad educativa debe concienciarse de esta situación y aunar esfuerzos para revertirlaThis research has assessed physical appearance satisfaction and distortion level between real image and self perceived image. In order to do that, BODY SHAPE (self-perceived) questionnaire has been administrated to 195 students whose ages vary from twelve to seventeen years old, as well as having measured their real weight and height. The achieved results show that boys are more dissatisfied in this way, furthermore they also have bigger distortion levels than girls. Analogously, while the age increases, a decrease of distortion is recorded, as well as a satisfaction level increase. However, the values are so alarming that the entire school community must be aware of this situation and join efforts to reverse it

El Trabajo Fin de Grado y su tutorización: un enfoque integrador entre áreas y participantes implicados

Fac. de Comercio y TurismoFALSEsubmitte

Appraisal of the suitability of two-stage extraction process by combining compressed fluid technologies of polar lipid fractions from chia seed

Although triacylglycerols (TAG) are the major constituents of chia oil, it also contains minor lipid fractions that include phospholipids (PL) among other desirable components. Its amphiphilic character and excellent biocompatibility make PL appropriate for numerous applications with technological and nutritional significanceand potential health benefits. Given the difficulties entailed by the PL isolation, the efficiency for extracting such compounds using two environmental friendly techniques, pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE) was evaluated. By using PLE with food-grade ethanol (EtOH), an oil recovery close to 100% was achieved in just 10 min. This oil extract was particularly rich in α-linolenic acid (ALA; 70%) as compared to the oil extracted by SFE (56%). In the case of SFE, the oil recovery was only 87% but increased to 99% when ethanol was added to CO2. However the use of co-solvent did not affect the fatty acid profile of the supercritical extracts or their TAG composition, where the high molecular weight TAG species were the predominant in all cases. With the exception of SFE without co-solvent, all methods applied were capable of extracting the PL fraction, although the content and distribution of the individual components present in this fraction differed markedly depending on the extraction conditions used. In this context, the use of a sequential extraction process, combining SFE and PLE was particularly interesting. The re-extraction by PLE of the chia cake, previously defatted by SFE, allowed to obtain an oil extract highly enriched in PLs, whose content exceeded 16% and with a higher PL species than the rest of the oil extractsThis study was supported in part by grants from the Spanish Ministry of Science, Innovation and Universities, Spain (AGL2017-87884 MINECO/AEI/FEDER, UE); by the Comunidad de Madrid through the B Programa de Actividades en Tecnologías, Spain (ALIBIRD-CM S2013/ABI-2728