The Impact of the Use of Large Non-Linear Lighting Loads in Low-Voltage Networks

The principal numerical and experimental results obtained by the authors on the harmonic power losses in low-voltage networks in the lighting area have been summarized in this review. Light-emitting diodes (LEDs) and compact fluorescent lamp (CFL) loads were considered. Four-core cables and four single-core cable arrangements were examined. The cables were modeled by using electromagnetic finite element analysis software. It was found that the cross section of the neutral conductor plays an important role in the derating of the cable ampacity due to the presence of a high level of triplen harmonics in the distorted current. In order to reduce the third-order harmonic currents in the neutral conductor, an experimental investigation of diversity factors for LED in combination with CFL and LED lamps was also performed. Attention was paid to the reduction of the third-order harmonic current, which is mainly responsible for the strong increase in power losses in the neutral conductor of low-voltage installations. The convenience of having LED lamps designed to operate as two-phase loads is suggested for certain applications

Análisis multidimensional de la estructura de las rutinas competitivas en natación sincronizada

El objetivo de este estudio fue caracterizar la estructura de las rutinas de solo y dúo de natación sincronizada. Para ello se utilizó un diseño observacional puntual, nomotético y multidimensional. El instrumento observacional ad hoc fue validado por 12 especialistas. Se utilizó como instrumento de registro el programa LINCE. La fiabilidad en la observación se determinó mediante el grado de concordancia intra e interobservador. Dieciocho nadadoras (seis medallistas olímpicas) participaron en el estudio. Se analizaron 39 rutinas: solo técnico (n = 9), solo libre (n = 11), dúo técnico (n = 10) y dúo libre (n = 9). El 61.6 ± 6.4 %) del tiempo de competición las nadadoras estaban con la cara dentro del agua, con apneas máximas de 21.1 ± 4.0 s. La posición más utilizada en el conjunto de rutinas fue la inferior (43.2 ± 5.3 %), siendo la fase de inmersión alta inferior la más reproducida (35.3 ± 5.0 %). En conclusión: 1) se dispone de una herramienta válida para el análisis de la estructura de las rutinas en natación sincronizada, 2) existen diferencias significativas en la estructura de las rutinas atendiendo a la duración total, las fases relativas de apnea y a la inmersión en distintas posiciones corporales.The aim of this study was to characterize the structure of solo and duet-based synchronized swimming routines. This was done using a specific nomothetic multidimensional observational design. The ad hoc observational instrument was validated by 12 specialists. The data was recorded using LINCE software, and observational reliability was determined by calculating the degree of intra-observer and inter-observer agreement. The participants were 18 female swimmers (including six Olympic medallists), and 39 routines were analysed: technical solos (n = 9), free solos (n = 11), technical duets (n = 10) and free duets (n = 9). The swimmers spent 61.6 ± 6.4 % of the competition time with their faces immersed in the water, with maximum apnea of 21.1 ± 4.0 s. The inverted-vertical position was the most widely taken in routines (43.2 ± 5.3 %), with the phase of deep immersion in that position being the most commonly reproduced (35.3 ± 5.0 %). In conclusion: 1) the observational instrument is a valid tool for analysing the structure of routines in synchronized swimming; and 2) there are significant differences in the structure of routines as regards their total duration, episodes of apnea, and the degree of immersion in different body positions.O objectivo deste estudo foi caracterizar a estrutura das rotinas individuais e duplas de natação sincronizada. Para tal foi utilizado um delineamento observacional pontual, nomotético e multidimensional. O instrumento observacional ad hoc foi validado por 12 especialistas. Utilizou-se como instrumento de registo o programa LINCE. A fidelidade na observação foi determinada mediante o grau de concordância intra e interobservador. Dezoito nadadoras (seis medalhistas olímpicas) participaram no estudo. Foram analisadas 39 rotinas; solo técnico (n = 9), solo livre (n = 11), duo técnico (n = 10) e duo livre (n = 9). As nadadoras estavam totalmente imersas na água em 61.6 % (± 6.4 %) do tempo de competição, com apneias máximas de 21.1 ± 4.0 s. A posição mais utilizada no conjunto de rotinas foi a imersão inferior (43.2 ± 5.3 %), sendo a fase de imersão total a mais reproduzida (35.3 ± 5.0 %). Em suma: 1) dispõem-se de uma ferramenta válida para a análise da estructura das rotinas na natação sincronizada, 2) existem diferenças significativas na estructura das rotinas atendendo à duração total, às fases relativas de apneia e à imersão em distintas posições corporais

Water-soluble polyphosphonate-based bottlebrush copolymers via aqueous ring-opening metathesis polymerization

Ring-opening metathesis polymerization (ROMP) is a versatile method for synthesizing complex macromolecules from various functional monomers. In this work, we report the synthesis of water-soluble and degradable bottlebrush polymers, based on polyphosphoesters (PPEs) via ROMP. First, PPE-macromonomers were synthesized via organocatalytic anionic ring-opening polymerization of 2-ethyl-2-oxo-1,3,2-dioxaphospholane using N-(hydroxyethyl)-cis-5-norbornene-exo-2,3-dicarboximide as the initiator and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the catalyst. The resulting norbornene-based macromonomers had degrees of polymerization (DPn) ranging from 25 to 243 and narrow molar mass dispersity (Đ ≤ 1.10). Subsequently, these macromonomers were used in ROMP with the Grubbs 3rd-generation bispyridyl complex (Ru-G3) to produce a library of well-defined bottlebrush polymers. The ROMP was carried out either in dioxane or in aqueous conditions, resulting in well-defined and water-soluble bottlebrush PPEs. Furthermore, a two-step protocol was employed to synthesize double hydrophilic diblock bottlebrush copolymers via ROMP in water at neutral pH-values. This general protocol enabled the direct combination of PPEs with ROMP to synthesize well-defined bottlebrush polymers and block copolymers in water. Degradation of the PPE side chains was proven resulting in low molar mass degradation products only. The biocompatible and biodegradable nature of PPEs makes this pathway promising for designing novel biomedical drug carriers or viscosity modifiers, as well as many other potential applications.</p

Comportamiento de fases del La2 CuO4+d debido al contenido de oxigeno

In-situ resistivity (T) measurements have been used in air ambient to study the phase behavior above room temperature of the La2 CuO4+ system, in samples thermically treated in order to obtain oxygenated and deoxygenated samples. Our results in oxygenated samples have shown an anomaly at around 600 K corresponding to the orthorhombic to tetragonal structural phase transition. However, this anomaly was observed&nbsp; with higher intensity in he first heating sweep in deoxygenated samples,&nbsp; which we have attributed to the fast oxygen in-diffusion into the sample at around this temperature.Usando medidas in situ de resistividad eléctrica (T) en ambiente de aire, hemos estudiado el comportamiento de fases por encima de la temperatura ambiente del sistema La2 CuO4+d , en muestras tratadas termicamente para obtener muestras con y sin deficiencias de oxigeno. Nuestros resultados en muestras sin deficiencia de oxigeno exhiben una anomalia en p(T) alrededor de 600k correspondiente&nbsp; a la transición de fase estructural de ortorrómbica a tetragonal. Sin embargo, esta anomalía se observó con bastante intensidad en el primer barrido de calentamiento en muestras con mínimo contenido de oxígeno, lo cual atribuimos a la rápida difusión de oxígeno hacia el volumen de la muestra alrededor de esta temperatura

Diversificación de patrones en rutinas de solo en natación sincronizada de alto nivel

El objetivo del presente estudio es determinar y caracterizar la existencia de diferencias estructurales y T-Patterns en la disposición corporal entre las rutinas de solo técnico y libre en la natación sincronizada de alto nivel. Se utilizó un diseño observacional puntual, nomotético y multidimensional. El instrumento de registro fue el programa LINCE v. 1.1. La #abilidad en la observación se determinó mediante el grado de concordancia intra e interobservador con valores de 0,9 en el índice Kappa. Se analizaron 15 nadadoras analistas del campeonato del Mundo y 11 del campeonato de España), en 19 rutinas de solo técnico) y 23 de solo libre). Se realizó un análisis descriptivo e inferencial de los registros, así como una detección de T-Patterns, mediante 6eme 6 Edu. Se detectó un mayor número de T-Patterns en el solo técnico que en el solo libre. El 69,3 % (±5,7) del tiempo total de rutina, las nadadoras están en fase de apnea, siendo mayores estos porcentajes en la rutina técnica que en la libre (p<0,05). Se encontraron diferencias significativas entre los tipos de rutina en el análisis de la posición corporal y los niveles de inmersión. En conclusión, podemos afirrmar que existen diferencias significativas entre las rutinas de solo libre y solo técnico tanto en la estructura temporal como en los T-Patterns detectados. Los programas técnicos se caracterizan por mayores porcentajes temporales en fases de apnea, elementos en baja inmersión y ejecuciones en posición inferior, así como en la cantidad de T-Patterns detectados

We are ready for faunistic surveys of bdelloid rotifers through DNA barcoding: the example of <i>Sphagnum</i> bogs of the Swiss Jura Mountains

The identification of biological diversity through DNA barcoding and metabarcoding of the organisms living in the field has the potential to revolutionise the way biological surveys and monitoring are performed. Yet, we still do not know if the current representativeness of the reference database of DNA sequence data is sufficient to allow such approaches. Here, we show that, at least for bdelloid rotifers (Metazoa; Rotifera; Bdelloidea) in Europe, current knowledge is ripe to perform such surveys. We show the results of an exercise performed on bdelloid rotifers in Sphagnum bogs of the Swiss Jura Mountain. The results of DNA-based identifications were rather consistent with the morphology-based identifications, and the few cases of mismatch could be used as a cautionary tale to avoid potential misinterpretations of results. The mismatches were due to cases of the closest match not being genetically very close, and to the occurrence of cryptic species.La identificación de la diversidad biológica a través de DNA barcoding y metabarcoding de los organismos en el medio ambiente tiene el potencial de revolucionar la forma en que se realizan los inventarios biológicos y el monitoreo. Sin embargo, todavía no se sabe si las bases de datos genéticos de referencia a disposición hoy en día son lo suficientemente representativas como para permitir tales enfoques. Aquí, mostramos que, al menos para los rotíferos bdelloideos (Metazoa; Rotifera; Bdelloidea) de Europa, el nivel de conocimiento es suficiente para realizar tales estudios. Mostramos los resultados de un ejercicio realizado sobre rotíferos bdelloideos en turberas de Sphagnum del Jura suizo. Los resultados de las identificaciones basadas en el ADN fueron bastante consistentes con las identificaciones basadas en la morfología, y los pocos casos de desajuste podrían utilizarse como una advertencia para evitar posibles interpretaciones erróneas de los resultados. Estos desajustes se debieron a que las secuencias más cercanas seguían alejadas de los organismos realmente encontrados y a la presencia de especies crípticas

Diversificación de patrones en rutinas de solo en natación sincronizada de alto nivel

El objetivo del presente estudio es determinar y caracterizar la existencia de diferencias estructurales y T-Patterns en la disposición corporal entre las rutinas de solo técnico y libre en la natación sincronizada de alto nivel. Se utilizó un diseño observacional puntual, nomotético y multidimensional. El instrumento de registro fue el programa LINCE v.1.1. La habilidad en la observación se determinó mediante el grado de concordancia intra e interobservador con valores de 0,9 en el índice Kappa. Se analizaron 15 nadadoras analistas del campeonato del Mundo y 11 del campeonato de España), en 19 rutinas de solo técnico) y 23 de solo libre). Se realizó un análisis descriptivo e inferencial de los registros, así como una detección de T-Patterns, mediante Theme 6 Edu. Se detectó un mayor número de T-Patterns en el solo técnico que en el solo libre. El 69,3 % (±5,7) del tiempo total de rutina, las nadadoras están en fase de apnea, siendo mayores estos porcentajes en la rutina técnica que en la libre (p&lt;0,05). Se encontraron diferencias significativas entre los tipos de rutina en el análisis de la posición corporal y los niveles de inmersión. En conclusión, podemos a#rmar que existen diferencias significativas entre las rutinas de solo libre y solo técnico tanto en la estructura temporal como en los T-Patterns detectados. Los programas técnicos se caracterizan por mayores porcentajes temporales en fases de apnea, elementos en baja inmersión y ejecuciones en posición inferior, así como en la cantidad de T-Patterns detectados

Singularities of surface mixing activity in the Western Mediterranean influence bluefin tuna larval habitats

Understanding how the surface dynamics of the ocean influence the spawning and larval ecology of many large pelagic species, in particular tuna species, is a major challenge. For temperate tunas, the selection of geographically restricted spawning grounds is influenced by environmental conditions, but the influence of surface mixing properties on the early life stages of these species remains poorly understood. Here, based on ichthyoplankton samples collected over 4 yr and satellite-derived finite size Lyapunov exponents (FSLEs), we examined how horizontal mixing activity drives the probability of presence of Atlantic bluefin tuna Thunnus thynnus larvae. We further analyzed the spatial and temporal scales of the FSLE variability at which the relationship between larval presence and mesoscale activity is maximized. We found that moderate mixing activity strongly favors the spatial-temporal distribution of larval habitats, evidencing an optimal environmental window of bluefin tuna spawning and early life development within the mesoscale dynamics. During the spawning season, the Balearic Sea presents a unique spatial and temporal hydrodynamic scenario within the Western Mediterranean. These results can be used for developing oceanographic indicators and improving larval abundance indices that are currently used in Atlantic bluefin tuna stock assessments.En prensa2,48

The OTELO survey. A case study of [O III]4959,5007 emitters at <z> = 0.83

The OTELO survey is a very deep, blind exploration of a selected region of the Extended Groth Strip and is designed for finding emission-line sources (ELSs). The survey design, observations, data reduction, astrometry, and photometry, as well as the correlation with ancillary data used to obtain a final catalogue, including photo-z estimates and a preliminary selection of ELS, were described in a previous contribution. Here, we aim to determine the main properties and luminosity function (LF) of the [O III] ELS sample of OTELO as a scientific demonstration of its capabilities, advantages, and complementarity with respect to other surveys. The selection and analysis procedures of ELS candidates obtained using tunable filter (TF) pseudo-spectra are described. We performed simulations in the parameter space of the survey to obtain emission-line detection probabilities. Relevant characteristics of [O III] emitters and the LF([O III]), including the main selection biases and uncertainties, are presented. A total of 184 sources were confirmed as [O III] emitters at a mean redshift z=0.83. The minimum detectable line flux and equivalent width (EW) in this ELS sample are $\sim$5 $\times$ 10$^{-19}$ erg s$^{-1}$ cm$^{2}$ and $\sim$6 \AA, respectively. We are able to constrain the faint-end slope ($\alpha = -1.03\pm0.08$) of the observed LF([O III]) at z=0.83. This LF reaches values that are approximately ten times lower than those from other surveys. The vast majority (84\%) of the morphologically classified [O III] ELSs are disc-like sources, and 87\% of this sample is comprised of galaxies with stellar masses of M$_\star$ $<$ 10$^{10}$ M$_{\odot}$.Comment: v1: 16 pages, 6 figures. Accepted in Astronomy \& Astrophysics. v2: Author added in metadat

Galaxy classification: deep learning on the OTELO and COSMOS databases

Context. The accurate classification of hundreds of thousands of galaxies observed in modern deep surveys is imperative if we want to understand the universe and its evolution. Aims. Here, we report the use of machine learning techniques to classify early- and late-type galaxies in the OTELO and COSMOS databases using optical and infrared photometry and available shape parameters: either the Sersic index or the concentration index. Methods. We used three classification methods for the OTELO database: 1) u-r color separation , 2) linear discriminant analysis using u-r and a shape parameter classification, and 3) a deep neural network using the r magnitude, several colors, and a shape parameter. We analyzed the performance of each method by sample bootstrapping and tested the performance of our neural network architecture using COSMOS data. Results. The accuracy achieved by the deep neural network is greater than that of the other classification methods, and it can also operate with missing data. Our neural network architecture is able to classify both OTELO and COSMOS datasets regardless of small differences in the photometric bands used in each catalog. Conclusions. In this study we show that the use of deep neural networks is a robust method to mine the cataloged dataComment: 20 pages, 10 tables, 14 figures, Astronomy and Astrophysics (in press