Technological solutions and laser processes for the development of superconductor-based applications.

El trabajo realizado en esta tesis doctoral aborda diferentes retos asociados con la implantación de tecnología superconductora en diversas aplicaciones. En la primera parte, se analiza la estabilidad térmica de cables y bobinas superconductoras. En particular, se ha estudiado la generación y propagación de quench en cables de diboruro de magnesio (MgB2) con geometría Rutherford. Se han empleado dos configuraciones para estudiar la dinámica de quench en estos conductores: la generación de calor localizada, simulando un punto caliente gracias a un calentador externo; y la aplicación de sobrecorrientes (corrientes por encima de la corriente crítica del cable). Además, se ha analizado la estabilidad térmica de una bobina tipo doble pancake fabricada con cinta de material superconductor de alta temperatura de segunda generación (2G-HTS), la cual se bobinó de forma continua y sin aislamiento entre espiras. La bobina se ancló térmicamente al dedo frío de un crio-generador para ser enfriada por conducción. Se ha analizado el comportamiento térmico y electromagnético de esta bobina incluyendo los procesos de carga y de descarga, la medida de la corriente crítica de la bobina, las pérdidas generadas, y sus diferentes contribuciones, durante las rampas de carga y descarga, así como la conductancia térmica que se establece en las diferentes uniones térmicas que se han utilizado para refrigerar la bobina.Para poder realizar estos estudios fue necesario inyectar de forma estable corrientes por encima de los 400 A. Esto supuso un reto por el calor generado en el equipo y en las barras de corriente, con un extremo a temperatura ambiente y otro a temperaturas criogénicas, por lo que son necesarios disipadores térmicos, que deben tener buena conductancia térmica y aislamiento eléctrico. En esta tesis se ha propuesto para esta aplicación emplear piezas de cobre recubiertas por una capa de alúmina proyectada por plasma, que es posteriormente densificada y re-fundida mediante el procesado láser de superficies, consiguiendo así una mejora notable de su conductividad térmica.Otro de los objetivos que se han abordado en este trabajo fue estudiar si las propiedades superconductoras pueden verse modificadas por la interacción con radiación láser. La versatilidad de las tecnologías láser permite facilitar la formación de nanoestructuras en la superficie del material con una disposición casi periódica, lo que abre un nuevo camino a la ingeniería de superficies. En esta tesis se ha estudiado como los tratamientos láser pueden modificar las propiedades superconductoras del material. Para estos estudios se han utilizado muestras de niobio por ser el elemento puro superconductor con una temperatura crítica y campos magnéticos críticos más altos. Dichas estructuras han sido generadas con distintos láseres: un láser ultravioleta con pulsos en el rango de cientos de picosegundos, y dos láseres que emiten pulsos en el infrarrojo cercano en el rango de los femtosegundos. Además, se han estudiado tratamientos en diferentes atmósferas. Esta modificación superficial es de gran interés para una aplicación directa del material, como es la construcción de cavidades resonantes de radio frecuencia.<br /

Parsimonious scenario for the emergence of viroid-like replicons de novo

This article belongs to the Special Issue Viroid-2018: International Conference on Viroids and Viroid-Like RNAs.Viroids are small, non-coding, circular RNA molecules that infect plants. Different hypotheses for their evolutionary origin have been put forward, such as an early emergence in a precellular RNA World or several de novo independent evolutionary origins in plants. Here, we discuss the plausibility of de novo emergence of viroid-like replicons by giving theoretical support to the likelihood of different steps along a parsimonious evolutionary pathway. While Avsunviroidae-like structures are relatively easy to obtain through evolution of a population of random RNA sequences of fixed length, rod-like structures typical of Pospiviroidae are difficult to fix. Using different quantitative approaches, we evaluated the likelihood that RNA sequences fold into a rod-like structure and bear specific sequence motifs facilitating interactions with other molecules, e.g., RNA polymerases, RNases, and ligases. By means of numerical simulations, we show that circular RNA replicons analogous to Pospiviroidae emerge if evolution is seeded with minimal circular RNAs that grow through the gradual addition of nucleotides. Further, these rod-like replicons often maintain their structure if independent functional modules are acquired that impose selective constraints. The evolutionary scenario we propose here is consistent with the structural and biochemical properties of viroids described to date.P.C. is supported by a Ramón Areces Foundation Postdoctoral Fellowship. The Spanish Ministerio de Ciencia, Innovación y Universidades-FEDER funds of the European Union support Projects BASIC (PGC2018-098186-B-I00, J.A.C. and P.C.), MiMevo (FIS2017-89773-P, S.M.), and EvolSysVir (BFU2015-65037-P, S.F.E.)

Caracterización y Simulación de un Diodo Schottky de Microondas

Presentado en el XXVIII Simposium Nacional de la Unión Científica Internacional de Radio. URSI 2013, Santiago de Compostela, 11 al 13 de septiembre de 2013.Microwave diode models included in commercial simulators use a large set of parameters, so they are often difficult to set up in order to match the actual response of a specific device. In this paper a simple model for a zero-bias microwave Schottky diode is presented. Noise characteristics are determined by measurements and then incorporated to the large signal model offered by the manufacturer in the diode datasheet. Using this model a diode power detector in large signal operation is simulated with commercial software, achieving excellent agreement with the measurement results, both in terms of power sensitivity and noise spectrum.Consejería de Economía, Innovación, Ciencia y Empleo de la Junta de Andalucía, mediante el proyecto P09-TIC-5268. Universidad de Málaga - Campus de Excelencia Internacional Andalucía Tec

Myristic acid potentiates palmitic acid-induced lipotoxicity and steatohepatitis associated with lipodystrophy by sustaning de novo ceramide synthesis.

Palmitic acid (PA) induces hepatocyte apoptosis and fuels de novo ceramide synthesis in the endoplasmic reticulum (ER). Myristic acid (MA), a free fatty acid highly abundant in copra/palmist oils, is a predictor of nonalcoholic steatohepatitis (NASH) and stimulates ceramide synthesis. Here we investigated the synergism between MA and PA in ceramide synthesis, ER stress, lipotoxicity and NASH. Unlike PA, MA is not lipotoxic but potentiated PA-mediated lipoapoptosis, ER stress, caspase-3 activation and cytochrome c release in primary mouse hepatocytes (PMH). Moreover, MA kinetically sustained PA-induced total ceramide content by stimulating dehydroceramide desaturase and switched the ceramide profile from decreased to increased ceramide 14:0/ceramide16:0, without changing medium and long-chain ceramide species. PMH were more sensitive to equimolar ceramide14:0/ceramide16:0 exposure, which mimics the outcome of PA plus MA treatment on ceramide homeostasis, than to either ceramide alone. Treatment with myriocin to inhibit ceramide synthesis and tauroursodeoxycholic acid to prevent ER stress ameliorated PA plus MA induced apoptosis, similar to the protection afforded by the antioxidant BHA, the pan-caspase inhibitor z-VAD-Fmk and JNK inhibition. Moreover, ruthenium red protected PMH against PA and MA-induced cell death. Recapitulating in vitro findings, mice fed a diet enriched in PA plus MA exhibited lipodystrophy, hepatosplenomegaly, increased liver ceramide content and cholesterol levels, ER stress, liver damage, inflammation and fibrosis compared to mice fed diets enriched in PA or MA alone. The deleterious effects of PA plus MA-enriched diet were largely prevented by in vivo myriocin treatment. These findings indicate a causal link between ceramide synthesis and ER stress in lipotoxicity, and imply that the consumption of diets enriched in MA and PA can cause NASH associated with lipodystrophy

The human CD53 gene, coding for a four transmembrane domain protein, maps to chromosomal region 1p13

The rat OX44/CD53 protein is the prototypic member of a"novel" family of proteins. These proteins are characterizedby four highly hydrophobic transmembrane domains, twosmall extracellular domains, one of which is extensively N-glycosylated,and both the amino and the carboxy terminus intracytoplasmic.This work has been supported by grants from Fundación Ramón Areces and CICYT (SAL90-0209 and SAL91-0043) to P.A.L. and FIS(92-0889) to S.R.CS

El conocimiento práctico en las maestras de 4º curso de Educación Infantil: distancia entre las teorías proclamadas y las teorías al uso

Actualmente los y las docentes deben ser profesionales competentes que den respuestas a las demandas educativas que se les plantean, asuman un rol docente polivalente, y sean conscientes del conocimiento práctico y pensamiento práctico que ponen en juego en su actividad diaria. Este trabajo forma parte de una investigación más extensa subvencionada por una convocatoria de ayuda a proyectos de I+D+i1 . En este caso, se pretende conocer las discrepancias existentes entre lo que los/as futuros/as docentes de Educación Infantil piensan que deben hacer, y lo que hacen, es decir, las contradicciones que existen entre las teorías proclamadas (pensamiento práctico) y las teorías al uso (conocimiento práctico). Para ello se ha realizado un estudio cualitativo, fundamentado en el estudio de casos, en el cual han participado 3 estudiantes de último curso, 3 docentes del Grado de Maestro/a en Educación Infantil, y un responsable del Equipo Decanal de la Universidad de Huelva. Los resultados ponen de manifiesto que, la interacción entre el discurso narrativo de las personas participantes y su verdadera práctica educativa es débil. Debido a esto es necesario plantear estrategias formativas fundamentadas en la reflexión e indagación profunda, donde se produzca una verdadera reconstrucción del conocimiento práctico o conocimiento inconsciente, y se pueden eliminar o acortar la distancia existente entre las teorías al uso y las teorías proclamadas.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Bridging the gap between researchers and patients: The role of the Institutional Review Boards in the informed consent process

Background: The Institutional-Review-Boards (IRB) frequently give unfavorable opinions to evaluated studies due to deficiencies in informed consent forms (ICFs), which delays the ethical approval of the study and increases waste in research. Objective: To analyze the extent to which IRB in our center gives unfavorable opinions due to documents deficiencies and to evaluate types of objection. Material and methods: Retrospective observational study of decisions during the first review by the IRB in our center (2012-2015). We carried out a systematic review of minutes when decisions on approval of studies are collected. If not approval, we analyzed appealed objections. Results: 1858 clinical studies were evaluated by the IRB. 1558 required informed consent for participating (83.9%, CI95%:82.1-85.5), 987 were not approved during the first review due to deficiencies in ICFs (63.3%, CI95%:60.9-65.7). The main causes of objections for non-approval were unreadability (11.7%, CI95%:10.6-12.9), inadequate information given about access to personal data rights (9.2%, CI95%:8.1-10.2), biological samples management (7.8%, IC95%:6.9-8.8), and expected benefits (7.6%, IC95%:6.7-8.6). Conclusions: Deficiencies in ICFs are an important reason for non-approval of protocols evaluated by an IRB. There are three fundamental weaknesses on which the IRB plays a key role: 1) improving readability; 2) adapting them to regulations concerning data protection and biological materials management; 3) avoiding misleading information towards enrollment

Bridging the gap between researchers and patients: The role of the Institutional Review Boards in the informed consent process

Background: The Institutional-Review-Boards (IRB) frequently give unfavorable opinions to evaluated studies due to deficiencies in informed consent forms (ICFs), which delays the ethical approval of the study and increases waste in research. Objective: To analyze the extent to which IRB in our center gives unfavorable opinions due to documents deficiencies and to evaluate types of objection. Material and methods: Retrospective observational study of decisions during the first review by the IRB in our center (2012-2015). We carried out a systematic review of minutes when decisions on approval of studies are collected. If not approval, we analyzed appealed objections. Results: 1858 clinical studies were evaluated by the IRB. 1558 required informed consent for participating (83.9%, CI95%:82.1-85.5), 987 were not approved during the first review due to deficiencies in ICFs (63.3%, CI95%:60.9-65.7). The main causes of objections for non-approval were unreadability (11.7%, CI95%:10.6-12.9), inadequate information given about access to personal data rights (9.2%, CI95%:8.1-10.2), biological samples management (7.8%, IC95%:6.9-8.8), and expected benefits (7.6%, IC95%:6.7-8.6). Conclusions: Deficiencies in ICFs are an important reason for non-approval of protocols evaluated by an IRB. There are three fundamental weaknesses on which the IRB plays a key role: 1) improving readability; 2) adapting them to regulations concerning data protection and biological materials management; 3) avoiding misleading information towards enrollment

Butler Matrix Based Six-port Passive Junction

In this work we propose the utilization of the Butler matrix as a six-port I/Q demodulator. The inherent symmetry of its topology allows to overcome the intrinsic amplitude and phase imbalances of the traditional approaches making it more suitable for the design of high performance six-port networks. To demonstrate the validity of the proposal a Butler matrix has been designed covering the complete UWB band and its results are compared with the traditional approaches

Epigenetic modifiers as potential therapeutic targets in diabetic kidney disease

Diabetic kidney disease is one of the fastest growing causes of death worldwide. Epigenetic regulators control gene expression and are potential therapeutic targets. There is functional interventional evidence for a role of DNA methylation and the histone post-translational modifications—histone methylation, acetylation and crotonylation—in the pathogenesis of kidney disease, including diabetic kidney disease. Readers of epigenetic marks, such as bromodomain and extra terminal (BET) proteins, are also therapeutic targets. Thus, the BD2 selective BET inhibitor apabetalone was the first epigenetic regulator to undergo phase-3 clinical trials in diabetic kidney disease with an endpoint of kidney function. The direct therapeutic modulation of epigenetic features is possible through pharmacological modulators of the specific enzymes involved and through the therapeutic use of the required substrates. Of further interest is the characterization of potential indirect effects of nephroprotective drugs on epigenetic regulation. Thus, SGLT2 inhibitors increase the circulating and tissue levels of β-hydroxybutyrate, a molecule that generates a specific histone modification, β-hydroxybutyrylation, which has been associated with the beneficial health effects of fasting. To what extent this impact on epigenetic regulation may underlie or contribute to the so-far unclear molecular mechanisms of cardio-and nephroprotection offered by SGLT2 inhibitors merits further in-depth studies.This research was funded by FIS/FEDER funds (PI15/00298, CP14/00133, PI16/01900, PI18/01386, PI18/0133, PI19/00588, PI19/00815, DTS18/00032, ERA-PerMed-JTC2018 (KIDNEY ATTACK AC18/00064 and PERSTIGAN AC18/00071), ISCIII-RETIC REDinREN RD016/0009), Sociedad Española de Nefrología, FRIAT, Comunidad de Madrid en Biomedicina B2017/BMD- 3686 CIFRA2-CM. Salary support: ISCIII Miguel Servet to ABS and MDS-N, ISCIII Sara Borrell to JM-MM, REDinREN RD016/0009 to MF-B, and MICIU to JG-M