Impact of noise on a dynamical system: prediction and uncertainties from a swarm-optimized neural network

In this study, an artificial neural network (ANN) based on particle swarm optimization (PSO) was developed for the time series prediction. The hybrid ANN+PSO algorithm was applied on Mackey--Glass chaotic time series in the short-term $x(t+6)$. The performance prediction was evaluated and compared with another studies available in the literature. Also, we presented properties of the dynamical system via the study of chaotic behaviour obtained from the predicted time series. Next, the hybrid ANN+PSO algorithm was complemented with a Gaussian stochastic procedure (called {\it stochastic} hybrid ANN+PSO) in order to obtain a new estimator of the predictions, which also allowed us to compute uncertainties of predictions for noisy Mackey--Glass chaotic time series. Thus, we studied the impact of noise for several cases with a white noise level ($\sigma_{N}$) from 0.01 to 0.1.Comment: 11 pages, 8 figure

Sanidad animal y comercio internacional

La condición sanitaria de los países y la inocuidad de sus productos se han convertido en la principal limitante para el comercio internacional de productos pecuarios, en un escenario de globalización y liberación de mercados. En este contexto, los países miembros de la Organización Mundial de Comercio han suscrito el Acuerdo para la Aplicación de Medidas Sanitarias y Fitosanitarias, cuyo principal objetivo es asegurar que las condiciones de sanidad e inocuidad no representarán barreras injustificadas para el comercio de productos agropecuarios, y al mismo tiempo generar las condiciones para que el comercio de los productos mencionados, no signifique un riesgo para la salud de personas o de poblaciones animales.Dicho escenario ha generado una gran responsabilidad para los Servicios Veterinarios Oficiales. Esto deben, por una parte, garantizar que productos pecuarios de exportación no representarán peligros para los países que importarán dichos productos, y complementariamente, proteger la salud de sus poblaciones animales, exigiendo la aplicación de las medidas sanitarias correspondientes a productos pecuarios de importación. Chile y el Servicio Agrícola y Ganadero han respondido a estos desafíos, desarrollando una política que tiene como objetivo, en el corto plazo, el posicionamiento de Chile como potencia agroalimentaria.  

Decomposition Analysis of the Aggregate Carbon Intensity (ACI) of the Power Sector in Colombia—A Multi-Temporal Analysis

This paper presents the application of the Logarithmic Mean Divisia Index Decomposition Analysis (LMDI) to the aggregate carbon intensity (ACI) of the power sector in Colombia in the period 1990–2020, with the aim of identifying the main drivers influencing the ACI change. The analysis performed identifies the main drivers among: carbon intensity, generation efficiency, and contribution of fossil generation at the specific and total level of electricity production. The analysis is performed at the aggregate and disaggregated level of fossil fuels. Due to the highly variable behavior of the ACI, a multi-temporal decomposition is performed in the eight presidential administrations in the period of analysis. For each period, the main drivers are identified and the energy policy implications and their effects on the operation and management of the power sector are analyzed. The results show that the main driver is the fossil share of total energy production. Important effects on thermal generation efficiency and fossil energy mix were also identified in some analysis periods. The need for effective long-term policies and regulation in relation to the factors influencing the ACI was identified. It is recommended to accelerate the diversification of the energy mix of the power sector and the permanent monitoring of the behavior of the drivers

Surfactant Protein C Deficiency in a Puerto Rican Adolescent With a Rare SFTPC Genetic Variant

Surfactant protein C (SP-C) is a hydrophobic lipoprotein necessary for lowering alveolar surface tension and lung defense mechanisms. Defects in its function due to genetic mutations in the SFTPC gene have been increasingly identified in patients presenting with childhood interstitial lung disease. SFTPC mutations are inherited in an autosomal dominant pattern with reduced penetration and variable expressivity, although de novo mutations have also been documented. In this article, we present the case of an oxygen-dependent 13-year-old male with interstitial lung disease and severe pulmonary hypertension. Genetic analysis and lung biopsy confirmed the diagnosis of SP-C deficiency with the rare heterozygous mutation IVS4+2. To our knowledge, this is the first documented case of SP-C deficiency in the Puerto Rican population and the second worldwide with the IVS4+2 genetic mutation

Estudios sobre el calor de hidratación desarrollado en morteros con materiales puzolánicos: naturales y subproductos industriales

The heat of hydration developed in reactions of mortars and concretes can be sensibly reduced using pozzolanic materials. However, the decrease of the heat of hydration is not directly proportional to the amount of cement substituted, because of the heat released in the pozzolanic reaction. With materials of high pozzolanic activity as silica fume or opaline rocks very, the heat is even increased.Con la incorporación de materiales con características puzolánicas en morteros y hormigones se puede rebajar el calor desarrollado en las reacciones de hidratación. Sin embargo, la disminución en el calor de hidratación no es directamente proporcional a la cantidad de cemento sustituido, esto es debido al aporte de calor generado en la reacción puzolánica, de forma que con materiales muy activos, como el humo de sílice o las rocas opalinas, incluso se incrementa

Desarrollo metodológico para la caracterización de caudales y niveles de sedimentación

La dinámica que ha alcanzado en Latinoamérica el desarrollo metodológico para el análisis de sistemas de producción, no ha tenido el mismo grado de desarrollo para la caracterización de la disponibilidad y uso de los recursos naturales. El objetivo de la investigación fue identificar metodologías sencillas, para estimar la producción de caudales y niveles de sedimentación a nivel de cuenca, de tal manera que estimule su incorporación a los procesos utinarios de caracterización de los sistemas de producción. La investigación se llevó a cabo en una subcuenca del río La Miel, donde actualmente se construye un importante complejo hidroeléctrico, cuya viabilidad depende de la disponibilidad del agua y de los niveles de sedimentación. Para la determinación del caudal se tomaron medidas de profundidad cada 5 cm en la lámina de agua, y se estableció una base fija para realizar mediciones diarias de altura, durante un año. El área del cauce se determinó, a partir de la altura diaria del nivel del río. La velocidad del cauce se determinó mediante el método del cuerpo flotante doble o subsuperficial, realizando regresiones de velocidad por altura del río. Para determinar el nivel de sedimentación, se midió la concentración de sólidos totales en muestras de agua tomadas diariamente,utilizando el método del turbidímetro. Los resultados indican un caudal promedio de 7.2 m3/s y un nivel de sedimentación de 48.61TM/ha.año, niveles que se ajustan a las estimaciones realizadas por otros métodos. La propuesta metodológica de medición de caudales, utilizando el flotador doble o subsuperficial, y la medición del área del cauce a partir de una regresión con la altura del nivel del río, resulta confiable, económica y de fácil acceso y aplicabilidad. La determinación indirecta de sedimentos, mediante la utilización del turbidímetro, aunque dependa de la disponibilidad de equipo, resultó económica y fácil de realizar

Implementing ARP-Path Low Latency Bridges in NetFPGA

The demo is focused on the implementation of ARP-Path (a.k.a. FastPath) bridges, a recently proposed concept for low latency bridges. ARP-Path Bridges rely on the race between broadcast ARP Request packets, to discover the minimum latency path to the destination host. Several implementations (in Omnet++, Linux, OpenFlow, NetFPGA) have shown that ARP-Path exhibits loop-freedom, does not block links, is fully transparent to hosts and neither needs a spanning tree protocol to prevent loops nor a link state protocol to obtain low latency paths. This demo compares our hardware implementation on NetFPGA to bridges running STP, showing that ARP-Path finds lower latency paths than STP.Comunidad de MadridJunta de Comunidades de Castilla-La Manch

Low-load resistance exercise completed to volitional failure decreases pain perception post-exercise in females and males

Exercise-induced hypoalgesia (EIH) is the acute pain reduction post-exercise. Typically, high-intensity and/or long-duration exercise is required to elicit EIH. Alternatively, low-load resistance exercise with blood flow restriction (LL+BFR) may elicit EIH. However, there is conflicting evidence regarding the necessary repetitions and volume load. This study evaluated EIH after 75 repetitions (1×30, 3×15) (BFR-75) and four sets to volitional failure (BFR-F) protocols. Twenty-six participants completed unilateral knee extensions at 30% of maximal strength using a BFR-75 and BFR-F protocol. Pain pressure threshold (PPT) of the rectus femoris was assessed before and after exercise. Repetitions completed, volume load, occlusion time, and PPT were analyzed. Participants completed more repetitions (91.4±30.5), volume load (5,204.9±2,367.0 Nm), and had a longer occlusion time (345.8±76.2 seconds) during BFR-F compared to BFR-75 (73.2±3.7 repetitions, 4,451.1±1,498.1 Nm, 300.5±52.2 seconds, respectively). Collapsed across sex, PPT increased from pre- (3.24±1.91 kgf) to post-exercise (3.76±2.27 kgf) for BFR-F but not BFR-75 (3.51±1.67 to 3.68±2.04 kgf). The results indicated that BFR-F, but not for BFR-75, elicited EIH, as assessed by an increase in PPT. Lower loads used during LL+BFR may be a clinically relevant alternative to high-intensity and/or long-duration exercise in populations that may not tolerate high-intensity or prolonged exercise to induce EIH

Zika virus epidemiology: From Uganda to world pandemic, an update

Zika virus (ZIKV) infection is an emergent worldwide public health problem. Historically, 84 countries have reported vector-borne ZIKV transmission, 61 of which report on-going transmission. It is a Flavivirus transmitted through arthropods belonging to the Aedes genus. Since 2015, ZIKV infections have increased dramatically; with 1.3 million people infected during 2015 in Brazil alone. This paper's objective is to highlight the conjectural epidemiological points of the virus' dissemination. The digital archives Pubmed, MEDLINE, EMBASE and Cochrane were searched for papers that assessed aspects of ZIKV transmission and epidemiology. The first isolation occurred in Uganda in 1947. Since then, important outbreaks were documented globally. Consequently, an emergent public health problem arose from a rapidly increasing incidence and its association with the development of neurological diseases such as microcephaly and Guillain-Barré syndrome. Key factors in the successful containment of outbreaks include surveillance of mosquitos in the neighbourhood, an early mosquito control treatment, an assertive information campaign, and the involvement of the local population and healthcare workers. As such, while ZIKV seems to be spreading globally in a similar manner to other arboviruses, such as Dengue and Chikungunya viruses, it can also be rapidly contained due to the pre-existing availability of necessary resources and regulatory tools as control measures. This review aims to provide a description of those characteristics of ZIKV infection that may be useful in the construction of effective outbreak control strategies. Copyright © Cambridge University Press 2018