Comparative theoretical analysis between parallel and perpendicular geometries for 2d particle patterning in photovoltaic ferroelectric substrates

This paper describes the dielectrophoretic potential created by the evanescent electric field acting on a particle near a photovoltaic crystal surface depending on the crystal cut. This electric field is obtained from the steady state solution of the Kukhtarev equations for the photovoltaic effect, where the diffusion term has been disregarded. First, the space charge field generated by a small, square, light spot where d ≪ l (being d a side of the square and l the crystal thickness) is studied. The surface charge density generated in both geometries is calculated and compared as their relation determines the different properties of the dielectrophoretic potential for both cuts. The shape of the dielectrophoretic potential is obtained and compared for several distances to the sample. Afterwards other light patterns are studied by the superposition of square spots, and the resulting trapping profiles are analysed. Finally the surface charge densities and trapping profiles for different d/l relations are studiedThis work was supported by the Spanish Ministerio de Economia y Competitividad under grants MAT2011-28379- C03 and MAT2014-57704-C

Design and Experimental Validation of Power Electric Vehicle Emulator for Testing Electric Vehicle Supply Equipment (EVSE) with Vehicle-to-Grid (V2G) Capability

Nowadays, the global decarbonization and electrification of the world’s energy demands have led to the quick adoption of Electric Vehicle (EV) technology. Therefore, there is an urgent need to provide a wide network of fast Vehicle-to-Grid (V2G) charging stations to support the forecast demand and to enable enough autonomy of such devices. Accordingly, V2G charging stations must be prepared to work properly with every manufacturer and to provide reliable designs and validation processes. In this way, the development of power electric vehicle emulators with V2G capability is critical to enable such development. The paper presents a complete design of a power electric vehicle emulator, as well as an experimental testbench to validate the behaviour of the proposal

Electrophoretic versus dielectrophoretic nanoparticle patterning using optoelectronic tweezers

Currently, there is increasing interest from many scientific disciplines in the development of systems that are able to sort and arrange many objects in parallel at the nano-and micrometric scale. Among others, photovoltaic tweezers (PVT) are an optoelectronic technique for trapping and patterning nano-and micro-objects in accordance with an arbitrary light profile. In this work, the differential features of electro-and dielectrophoretic (EP and DEP) nanoparticle (NP) patterning using PVT are deeply investigated. The study is carried out through theory and experiments. The developed theory extends the applicability of a previously reported model to be able to compute EP potentials and to obtain numerical values for the EP and DEP potential energies. Two-dimensional patterns of charged and neutral aluminum NPs are fabricated on top of Fe:LiNbO3 crystals, and different light distributions and other experimental parameters (crystal thickness and NP concentration) are compared. Patterns of charged and neutral NPs show remarkable differences in both particle density distribution and fidelity to the original light profile. The observed different features between EP and DEP trapping are satisfactorily explained by the theoretical analysis. The results provide routes for the optimization of the NP arrangements for both regimes.This work is supported by the Spanish Ministerio de Economía y Competitividad under Grant No. MAT201457704-C3. J.F.M.-M. is partially supported by a fellowship of the Universidad Politécnica de Madrid (Grant No. RR01/2016

Diffractive optical devices produced by light-assisted trapping of nanoparticles

© 2015 Optical Society of America.]. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibitedOne and two-dimensional diffractive optical devices have been fabricated by light assisted trapping and patterning of nanoparticles. The method is based on the dielectrophoretic forces appearing in the vicinity of a photovoltaic crystal, such as Fe:LiNbO3, during or after illumination. By illumination with the appropriate light distribution, the nanoparticles are organized along patterns designed at will. One- and two-dimensional diffractive components have been achieved on X- and Z-cut Fe:LiNbO3 crystals, with their polar axes parallel and perpendicular to the crystal surface, respectively. Diffraction gratings with periods down to around a few micrometers have been produced using metal (Al, Ag) nanoparticles with radii in the range of 70-100 nm. Moreover, several 2D devices, such as Fresnel zone plates, have been also produced showing the potential of the method. The diffractive particle patterns remain stable when light is removed. A method to transfer the diffractive patterns to other non-photovoltaic substrates, such as silica glass, has been also reportedThis work was supported by Spanish projects MAT2011- 28379-C03 and MAT2014-57704-C0

Investigating mutations in the genes GDF9 and BMP15 in Pelibuey sheep through the amplification-refractory mutation system with tetra-primers

Single Nucleotide Polymorphisms (SNP) or mutations are variations with a broad distribution in the genome and, as part of genetic studies, SNP allow the identification of allelic variants related to characteristics of economic importance in sheep production. However, the identification of SNP and their genotypes through sequencing is expensive, as it requires specialized materials and equipment. The objective of this study was to identify polymorphisms and their genotypes in the growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) genes in Pelibuey sheep using the tetra-primer amplification-refractory mutation system through polymerase chain reaction (T-ARMS-PCR). DNA extraction and amplification of BMP15 and GDF9 were conducted from blood samples contained in WhatmanTM FTATM cards from 60 multiparous Pelibuey ewes with reproductive records. The T-ARMS-PCR methodology allowed the identification of wild-type genotypes and mutated homozygous genotypes in polymorphisms G4 and G6 of GDF9, whereas mutations in the BMP15 gene were not found. These results were confirmed by sequencing. In conclusion, the T-ARMS-PCR methodology allowed the identification of mutated and wild-type genotypes in SNP G4 and G6 of GDF9, although no mutations were found in BMP15 in Pelibuey sheep. This technique was found to be reliable, rapid, and easily applied to identify polymorphic genotypes

Caracterización genética de las razas Hartón del Valle, Angus, Brangus, Holstein y Senepol en Colombia, usando 10 marcadores microsatélites

ABSTRACT: The objective of this paper is to establish a genetic characterization of the Senepol (S, n=49), Holstein (H, n= 60), Hartón del Valle (HV, n=60), Angus (A, n=61) and Brangus (Br, n=60) cattle breeds in Colombia, by using the following microsatellite markers: SPS115, INRA64, ETH225, ETH10, BM1824, INRA37, TGLA122, TGLA126, INRA32, and BM2113. A total of 142 alleles were obtained for ten analyzed loci, considering the five cattle breeds as a whole. The number of alleles per locus ranged from 9 (INRA64 and 1824) to 22 (TGLA122). The expected heterozygosity was between 0.79 (INRA32) and 0.90 (INRA37) in all the cattle breeds, respectively; and medium heterozygosity was 0.84. The average number of alleles per breed varied from 9.2 in the Senepol breed to 10.3 in the Holstein breed. The expected heterozygosity range varied from 0.75 in the Hartón del Valle breed and 0.82 in the Holstein breed, with an average of 0.79. Hardy Wienberg disequilibrium was observed (p>0.05) when the populations were analyzed with all the markers. All the populations presented a heterozygote deficit, which could be the result of a strong endogamy tendency within all the herds. The markers used in this study allowed a genetic characterization of the analyzed populations. The microsatellites panel in the Hartón del Valle breed should be increased in order to increase the reliability value. Microsatellite panels could solve parenthood cases for the remainder breeds.RESUMEN: El objetivo de este trabajo fue caracterizar genéticamente las razas bovinas Senepol (S, n=49), Holstein (H, n= 60), Hartón del Valle (HV, n=60), Angus (A, n=61) y Brangus (Br, n=60) en Colombia, con los marcadores microsatélites SPS115, INRA64, ETH225, ETH10, BM1824, INRA37, TGLA122, TGLA126, INRA32 y BM2113. En total, 142 alelos fueron encontrados en los diez loci analizados, considerando las cinco razas como un todo. El número de alelos por locus estuvo entre 9 (INRA64 y BM1824) y 22 (TGLA122). La Heterocigosidad esperada a través de todas las razas varió entre 0.79 (INRA32) y 0,90 (INRA37) y heterocigosidad media esperada de 0.84. El número promedio de alelos por raza varió de 9.2 en la raza S a 10.3 en la raza H. El rango de la Heterocigosidad esperada entre las razas varió entre 0.75 en la raza HV y 0.82 en la raza H, con una media de 0.79. Al analizar las poblaciones con el total de marcadores, todas se encontraron en desequilibrio de Hardy Weinberg (p>0.05). Todas las poblaciones presentaron un déficit de heterocigotos, para todas las poblaciones, lo que podría ser el resultado de la fuerte tendencia a la endogamia dentro de los diferentes hatos. Los resultados indicaron que los marcadores utilizados en este estudio permitieron caracterizar genéticamente las poblaciones analizadas. En el caso de la Raza HV, se debe aumentar el panel de microsatélites para aumentar el valor de confiabilidad. Para las demás razas el panel de microsatélites permitiría resolver casos de filiación

Cardio-ankle vascular index (CAVI) measured by a new device: protocol for a validation study

This study was funded by Consejeria de Economia e Infraestructura de la Junta de Extremadura (Spain) (Grant no: IB16218).Introduction Cardio-ankle vascular index (CAVI) is a new marker of arterial stiffness (AS) that can assess vascular wall stiffness in the aorta, femoral artery and tibial artery. CAVI is less affected by blood pressure at the time of measurement than the gold standard method (carotid-femoral pulse wave velocity (PWV)). Our group has developed a device called VOPITB (Velocidad Onda de Pulso Índice Tobillo Brazo) that uses the oscillometric method and easily and accurately measures the PWV in the arms and legs separately, allowing new AS indices to be studied. This article describes the research protocol to determine CAVI using VOPITB and to validate the device against a reference device (VaSera VS-1500) and assess its clinical utility. Methods and analyses A cross-sectional, descriptive and observational study will be conducted. In all, 120 subjects (a minimum of 40% of subjects from any one gender) will be evaluated. CAVI will be determined from the measurement by VOPITB and VaSera VS-1500. For each subject, the average of the three readings taken with each device will be calculated. The Bland-Altman plot will be used to determine whether any bias exists in the data -that is, a tendency of the size of the difference to vary with the mean. The participants will be divided roughly equally between the following age bands: 60 years. Ethics and dissemination The study has been approved by the ethics committee of the Hospital San Pedro de Alcántara, Cáceres, Spain. The participants will be required to sign an informed consent form before inclusion in the study, in accordance with the Declaration of Helsinki and WHO standards for observational studies. The dissemination plan of the research study results will be through presentations in relevant national and international conferences and scientific publications in peer-reviewed journals. Trial registration number NCT04303546.publishersversionpublishe

Unconventional superconductivity mediated by spin fluctuations in single-layer NbSe2

Van der Waals materials provide an ideal platform to explore superconductivity in the presence of strong electronic correlations, which are detrimental of the conventional phonon-mediated Cooper pairing in the BCS-Eliashberg theory1 and, simultaneously, promote magnetic fluctuations. Despite recent progress in understanding superconductivity in layered materials, the glue pairing mechanism remains largely unexplored in the single-layer limit, where electron-electron interactions are dramatically enhanced. Here we report experimental evidence of unconventional Cooper pairing mediated by magnetic excitations in single-layer NbSe2, a model strongly correlated 2D material. Our high-resolution spectroscopic measurements reveal a characteristic spin resonance excitation in the density of states that emerges from the quasiparticle coupling to a collective bosonic mode. This resonance, observed along with higher harmonics, gradually vanishes by increasing the temperature and upon applying a magnetic field up to the critical values (TC and HC2), which sets an unambiguous link to the superconducting state. Furthermore, we find clear anticorrelation between the energy of the spin resonance and its harmonics and the local superconducting gap({\Delta}), which invokes a pairing of electronic origin associated with spin fluctuations. Our findings demonstrate the fundamental role that electronic correlations play in the development of superconductivity in 2D transition metal dichalcogenides, and open the tantalizing possibility to explore unconventional superconductivity in simple, scalable and transferable 2D superconductors.Comment: Manuscript and SI. Comment are welcom

Ventricular Fibrillation detection using time-frequency and the KNN classifier without parameter extraction

[ES] Este trabajo propone la detección de FV y su discriminación de TV y otros ritmos cardiacos basándose en la representación tiempo-frecuencia del ECG y su conversión en imágen como entrada a un clasificador de vecinos más cercanos (KNN) sin necesidad de extracción de parámetros adicionales. Tres variantes de datos de entrada al clasificador son evaluados. Los resultados clasifican la señal en cuatro clases diferentes: ’Normal’ para latidos con ritmo sinusal, ’FV’ para fibrilación ventricular, ’TV’ para taquicardia ventricular y ’Otros’ para el resto de ritmos. Los resultados para detección de FV mostraron 88,27% de sensibilidad y 98,22% de especificidad para la entrada de imágen equivalente reducida que es la más rápida computacionalmente a pesar de obtener resultados de clasificación ligeramente inferiores a las representaciones no reducidas. En el caso de TV, se alcanzó un 88,31% de sensibilidad y 98,80% de especificidad, un 98,14% de sensibilidad y 96,82% de especificidad para ritmo sinusal normal y 96,91% de sensibilidad con 99,06% de especificidad para la clase ’Otros’. Finalmente, se realiza una comparación con otros algoritmos.[EN] This work describes new techniques to improve VF detection and its separation from Ventricular Tachycarida (VT) and other rhythms. It is based on time-frequency representation of the ECG and its use as input in an automatic classifier (K-nearest neighbours - KNN) without any further signal parameter extraction or additional characteristics. For comparison purposes, three time-frequency variants are analysed: pseudo Wigner-Ville representation (RTF), grey-scale image obtained from RTF (IRTF), and reduced image from IRTF (reduced IRTF). Four types of rhythms (classes) are defined: ’Normal’ for sinus rhythm, ’VT’ for ventricular tachycardia, ’VF’ for ventricular fibrillation and ’Others’ for the rest of rhythms. Classification results for VF detection in case of reduced IRTF are 88.27% sensitivity and 98.22% specificity. In case of VT, 88.31% sensitivity and 98.80% specificity is obtained, 98.14% sensitivity and 96.82% specificity for normal rhythms, and 96.91% sensitivity and 99.06% specificity for other rhythms. Finally, results are compared with other authors.Mjahad, A.; Rosado Muñoz, A.; Bataller Mompeán, M.; Francés Víllora, JV.; Guerrero Martínez, JF. (2017). Detección de Fibrilación Ventricular Mediante Tiempo-Frecuencia y Clasificador KNN sin Extracción de Parámetros. Revista Iberoamericana de Automática e Informática industrial. 15(1):124-132. https://doi.org/10.4995/riai.2017.8833OJS124132151Classen, T. A. C. M., Mecklenbrauker, W. F. G., 1980. 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Revealing giant exciton fine-structure splitting in 2D perovskites using van der Waals passivation

The study of two-dimensional (2D) van der Waals materials has been an active field of research in the development of new optoelectronics and photonic applications over the last decade. Organic-inorganic layered perovskites are currently some of the most promising 2D van der Waals materials, due to their exceptional optical brightness and enhanced excitonic effects. However, low crystal quality and spectral diffusion usually broaden the exciton linewidth, obscuring the fine structure of the exciton in conventional photoluminescence experiments. Here, we propose a mechanical approach for reducing the effect of spectral diffusion by means of hBN-capping on layered perovskites with different thicknesses, revealing the exciton fine structure. We used a stochastic model to link the reduction of the spectral linewidth with the population of active charge fluctuation centres present in the organic spacer taking part in the dynamical Stark shift. Active fluctuation centres are reduced by a factor of 3.7 to 7.1 when we include hBN-capping according to our direct spectral measurements. This rate is in good agreement with the analysis of the overlap between the squared perovskite lattice and the hexagonal hBN lattice. Van der Waals forces between both lattices cause the partial clamping of the perovskite organic spacer molecules, and hence, the amplitude of the dynamical Stark shift characteristic of the spectral diffusion effect is reduced. Our work provides an easy and low-cost solution to the problem of accessing important fine-structure excitonic state information, along with an explanation of the important carrier dynamics present in the organic spacer that affect the quality of the optical emission