The logarithmic spiral, autoisoptic curve

In the Line of Investigation that in the department of “Technical Drawing” in the School of Agriculture Engineering of Madrid, we carry out on the study of The Technical Curves and his singularities, we demonstrate an interesting property of the Logarithmic Spiral. The demonstrated property consists of which the logarithmic spiral is a autoisoptic curve, that is to say that if from a point P anyone of the spiral tangent straight lines draw up to the previous arc, these form a constant angle α. This demonstration is novel and in addition we get to contribute a method to calculate the angle α given the equation of the spiral

On the design of Aircraft Electrical Structure Networks

As part of the technology research engaged in the EU Clean Sky 1 project, we present in this paper an electrical structure network (ESN) designed to prevent the impact on an electronic equipment of unwanted voltage drops appearing when nonmetal composite materials are used for grounding. An iterative process has been followed to reach an optimal tradeoff solution meeting all the aircraft requirements: structural, safety, low weight, electrical, etc. Guidelines on the design of a low-impedance metal ESN, to minimize the inductive behavior of the power distribution network, are outlined in this paper. To this end, we employ the UGRFDTD simulation tool, combining finite-difference time domain to analyze the general EM problem, and a multiconductor transmission-line network to handle internal coupling between cables running along coinciding routes. The capability of this tool to create time-domain snapshots of surface currents is shown to provide a useful way to optimize the ESN, thanks to the insight gained on the physics of the problem.This work was supported from the European Community Seventh Framework Program FP7/2008-2014 under Grant CSJU-GAM-GRA- 2008-01 (Clean Sky 1 project), and from the Projects TEC2013-48414-C3- 01 and TEC2015-68766-REDC (MINECO, Spain), P12-TIC-1442 (Junta de Andalucia, Spain), Alhambra-UGRFDTD (AIRBUS DS), and by the CSIRC alhambra.ugr.es supercomputing cente

Estudio de accesibilidad a las zonas verdes urbanas mediante Sistemas de Información Geográfica

La creciente preocupación por parte de la sociedad respecto del medio ambiente que nos rodea, ha hecho que las administraciones de ámbito local recojan las inquietudes de los ciudadanos e intenten dar soluciones mediante la creación de lo que se viene a denominar espacios verdes urbanos: son nuestros parques y jardines públicos. Sin embargo, día a día surgen nuevas demandas por parte de los distintos grupos sociales, pasando de la mera creación o representación estética del campo en la ciudad a dotar a estos entornos de elementos en los que la practicidad toma un valor relevante. El objetivo del presente trabajo es servir como instrumento de información a las distintas administraciones en su labor de planificación de zonas verdes urbanas utilizando para ello Sistemas de Información Geográfic

A smart power electronic multiconverter for the residential sector

El futuro de la red incluye la generación distribuida y las tecnologías de red inteligente. Los sistemas de gestión del lado de la demanda (DSM) también serán esenciales para lograr un alto nivel de confiabilidad y robustez en los sistemas de energía. Para hacer eso, es necesario expandir la Infraestructura de medición avanzada (AMI) y los Sistemas de gestión de energía (EMS). La dirección de la tendencia es hacia la creación de centros de recursos energéticos, como el concepto de comunidad inteligente. Este documento presenta un sistema multiconvertidor inteligente para el sector residencial / vivienda con un Sistema de Almacenamiento de Energía Híbrido (HESS) que consta de supercapacitador y batería, y con integración de fuente de energía fotovoltaica (PV) local. El dispositivo funciona como una unidad de energía distribuida ubicada en cada casa de la comunidad, recibiendo puntos de ajuste de energía activos proporcionados por una comunidad inteligente EMS. Este SGA central es responsable de administrar los flujos de energía activa entre la red eléctrica, las fuentes de energía renovables, los equipos de almacenamiento y las cargas existentes en la comunidad. El multiconvertidor propuesto es responsable de cumplir con los puntos de referencia de potencia activa de referencia con la calidad de potencia adecuada; garantizando que los módulos fotovoltaicos locales funcionen con un algoritmo de seguimiento del punto de máxima potencia (MPPT); y prolongando la vida útil de la batería gracias a un funcionamiento cooperativo del HESS. Se ha desarrollado un modelo de simulación para mostrar el funcionamiento detallado del sistema. Finalmente, se implementó un prototipo de la plataforma de multiconversores y se realizaron algunas pruebas experimentales para validarlo.The future of the grid includes distributed generation and smart grid technologies. Demand Side Management (DSM) systems will also be essential to achieve a high level of reliability and robustness in power systems. To do that, expanding the Advanced Metering Infrastructure (AMI) and Energy Management Systems (EMS) are necessary. The trend direction is towards the creation of energy resource hubs, such as the smart community concept. This paper presents a smart multiconverter system for residential/housing sector with a Hybrid Energy Storage System (HESS) consisting of supercapacitor and battery, and with local photovoltaic (PV) energy source integration. The device works as a distributed energy unit located in each house of the community, receiving active power set-points provided by a smart community EMS. This central EMS is responsible for managing the active energy flows between the electricity grid, renewable energy sources, storage equipment and loads existing in the community. The proposed multiconverter is responsible for complying with the reference active power set-points with proper power quality; guaranteeing that the local PV modules operate with a Maximum Power Point Tracking (MPPT) algorithm; and extending the lifetime of the battery thanks to a cooperative operation of the HESS. A simulation model has been developed in order to show the detailed operation of the system. Finally, a prototype of the multiconverter platform has been implemented and some experimental tests have been carried out to validate it.Ministerio de Economía y Competitividad (España) y Fondos FEDER: Proyecto TEC2013-47316-C3-3-PpeerReviewe

Neutron cross-sections for advanced nuclear systems: the n_TOF project at CERN

E2C 2013 – 3rd European Energy ConferenceThe study of neutron-induced reactions is of high relevance in a wide variety of fields, ranging from stellar nucleosynthesis and fundamental nuclear physics to applications of nuclear technology. In nuclear energy, high accuracy neutron data are needed for the development of Generation IV fast reactors and accelerator driven systems, these last aimed specifically at nuclear waste incineration, as well as for research on innovative fuel cycles. In this context, a high luminosity Neutron Time Of Flight facility, n_TOF, is operating at CERN since more than a decade, with the aim of providing new, high accuracy and high resolution neutron cross-sections. Thanks to the features of the neutron beam, a rich experimental program relevant to nuclear technology has been carried out so far. The program will be further expanded in the near future, thanks in particular to a new high-flux experimental area, now under constructio

Light-Emitting-Diodes based on ordered InGaN nanocolumns emitting in the blue, green and yellow spectral range

The growth of ordered arrays of InGaN/GaN nanocolumnar light emitting diodes by molecular beam epitaxy, emitting in the blue (441 nm), green (502 nm), and yellow (568 nm) spectral range is reported. The device active region, consisting of a nanocolumnar InGaN section of nominally constant composition and 250 to 500 nm length, is free of extended defects, which is in strong contrast to InGaN layers (planar) of similar composition and thickness. The devices are driven under pulsed operation up to 1300 A/cm2 without traces of efficiency droop. Electroluminescence spectra show a very small blue shift with increasing current, (almost negligible in the yellow device) and line widths slightly broader than those of state-of-the-art InGaN quantum wells

Catalytic activity of MWCNT-based inks synthetized by different methods

Abstract of the poster presented at "Current Trends in Electrochemistry", 41st Meeting of the Electrochemistry Group of the Spanish Royal Society of Chemistry and 1st French-Spanish Atelier/Workshop on Electrochemistry, Paris (July 6 - 9, 2021).Research on new catalyst materials for the oxygen reduction reaction (ORR) is the main goal for many research groups around the world, due to its application in fuel cells and metal/air batteries. ORR mainly occurs by two pathways, in alkaline media, the direct four-electron transfer pathway from O2 to OH- or in a two-steps mechanism, where hydrogen peroxide (HO2-) is formed in the first reaction. On fuel cells and metal air batteries applications, the catalyst must be optimized to get the oxygen reduced directly to water through the 4 electrons mechanism1. Due to high price of the precious metals, new materials are tested to be used as catalyst in ORR. Among them, researchers have focused their attention mainly on metal oxides, perovskites or carbonaceous materials. In this communication, we have studied four carbonaceous-based inks synthetized by ultrasonic or hydrothermal methods2, using a rotating ring-disk electrode (RRDE) (Figure 1.A). The production of HO2- (%HO2-), transferred electrons and others parameters will be analyzed and the results will be discussed in depth. Finally, the inks were used as catalysts in the cathode of a PVA-KOH-based zinc/air batteries to replace the most widely used catalyst to date, MnO2The authors thank the financial support from Fundación Séneca (Región de Murcia, Spain; Ref: 20985/PI/18 and 19882-GERM-15), Spanish Agencia Estatal de Investigación (PID2019-104272RB-C55/ AEI/10.13039/501100011033 and PID2019-104272RB-C51/AEI/10.13039/501100011033), and Gobierno de Aragón (DGA T03_20R).Peer reviewe

Medición de parámetros fisicos, biológicos y químicos en el tramo estuarino del río Ebro

En este artículo se describen las campañas de campo CYTMAR I y II realizadas en la primavera y el verano de 1997, con el fin de estudiar los procesos y los flujos físicos, biológicos y químicos en la zona del Delta del Ebro, tanto en el tramo estuarino del río como en la pluma de agua dulce que se forma en las cercanías de la desembocadura. Aquí el estudio se ha centrado en la zona estuarina, presentando algunos resultados preliminares y analizando las diferencias estacionales observadas

Review of Pharmacokinetics and Pharmacogenetics in Atypical Long-Acting Injectable Antipsychotics

Over the last two decades, pharmacogenetics and pharmacokinetics have been increasingly used in clinical practice in Psychiatry due to the high variability regarding response and side effects of antipsychotic drugs. Specifically, long-acting injectable (LAI) antipsychotics have different pharmacokinetic profile than oral formulations due to their sustained release characteristics. In addition, most of these drugs are metabolized by CYP2D6, whose interindividual genetic variability results in different metabolizer status and, consequently, into different plasma concentrations of the drugs. In this context, there is consistent evidence which supports the use of therapeutic drug monitoring (TDM) along with pharmacogenetic tests to improve safety and efficacy of antipsychotic pharmacotherapy. This comprehensive review aims to compile all the available pharmacokinetic and pharmacogenetic data regarding the three major LAI atypical antipsychotics: risperidone, paliperidone and aripiprazole. On the one hand, CYP2D6 metabolizer status influences the pharmacokinetics of LAI aripiprazole, but this relation remains a matter of debate for LAI risperidone and LAI paliperidone. On the other hand, developed population pharmacokinetic (popPK) models showed the influence of body weight or administration site on the pharmacokinetics of these LAI antipsychotics. The combination of pharmacogenetics and pharmacokinetics (including popPK models) leads to a personalized antipsychotic therapy. In this sense, the optimization of these treatments improves the benefit–risk balance and, consequently, patients’ quality of lifeThis project was partially supported by Fundación Española de Farmacia Hospitalaria “Convocatoria de ayudas de proyectos para grupos de trabajo de la SEFH 2021-2022”, Plan Galego de Saude Mental (SERGAS) and Axencia Galega Innovación (Grupos de Potencial Crecimiento IN607B2020/11). Bandín-Vilar E.: Mondelo-García C. and Fernández-Ferreiro A. are grateful to the Carlos III Health Institute for financing their personnel contracts: CM20/00135, JR20/00026 and JR18/00014S

A Complex Regulatory Network Governs the Expression of Symbiotic Genes in Sinorhizobium Fredii HH103

Introduction: The establishment of the rhizobium-legume nitrogen-fixing symbiosis relies on the interchange of molecular signals between the two symbionts. We have previously studied by RNA-seq the effect of the symbiotic regulators NodD1, SyrM, and TtsI on the expression of the symbiotic genes (the nod regulon) of Sinorhizobium fredii HH103 upon treatment with the isoflavone genistein. In this work we have further investigated this regulatory network by incorporating new RNA-seq data of HH103 mutants in two other regulatory genes, nodD2 and nolR. Both genes code for global regulators with a predominant repressor effect on the nod regulon, although NodD2 acts as an activator of a small number of HH103 symbiotic genes. Methods: By combining RNA-seq data, qPCR experiments, and b-galactosidase assays of HH103 mutants harbouring a lacZ gene inserted into a regulatory gene, we have analysed the regulatory relations between the nodD1, nodD2, nolR, syrM, and ttsI genes, confirming previous data and discovering previously unknown relations. Results and discussion: Previously we showed that HH103 mutants in the nodD2, nolR, syrM, or ttsI genes gain effective nodulation with Lotus japonicus, a model legume, although with different symbiotic performances. Here we show that the combinations of mutations in these genes led, in most cases, to a decrease in symbiotic effectiveness, although all of them retained the ability to induce the formation of nitrogen-fixing nodules. In fact, the nodD2, nolR, and syrM single and double mutants share a set of Nod factors, either overproduced by them or not generated by the wild-type strain, that might be responsible for gaining effective nodulation with L. japonicus.Ministerio de Ciencia e Innovación PID2019-107634RB-I0