Level of characterization development reached by Santiago badmintonists in decision making

The act of deciding is considered one of the current research problems of Sports Psychology. It is important to know what athletes think, how they analyze game situations and how they make decisions during vital moments of obtaining a satisfactory sporting result. The decision-making guarantees, then, the rapid adaptation of the athlete to emergent situations of training and competition. Badminton as a sport of high strategy demands in those who practice it, perceptual, decisive and execution skills. From a descriptive study, having as sample six badmintonists from Santiago, it is intended to characterize the level of development reached by the latter in decision making. Techniques such as the memory stimulation interview, coach interviews and the game performance evaluation instrument (GPAI) are used as an observation protocol. The present characterization shows that in training and competition, badmintonists present difficulties in the perceptual-cognitive, decisive and executive indicators of the decision process. They also reveal the technical-methodological limitations of the coach in the development of the said process in his athletes

Effect of the anodization voltage on the porewidening rate of nanoporous anodic alumina

A detailed study of the pore-widening rate of nanoporous anodic alumina layers as a function of the anodization voltage was carried out. The study focuses on samples produced under the same electrolyte and concentration but different anodization voltages within the self-ordering regime. By means of ellipsometry-based optical characterization, it is shown that in the porewidening process, the porosity increases at a faster rate for lower anodization voltages. This opens the possibility of obtaining three-dimensional nanostructured nanoporous anodic alumina with controlled thickness and refractive index of each layer, and with a refractive index difference of up to 0.24 between layers, for samples produced with oxalic acid electrolytes

Diversité linguistique, langues menacées et développement durable

262 p.The UNESCO Chair on World Language Heritage at the University of the Basque Country (UPV/EHU) has carried out different linguistic cooperation activities which have shown that the effort made, particularly by the local community itself, always has a positive effect. Traditionally, we have had the right to be educated in “vernacular language”. This was the name given at that time to native or indigenous languages, which were generally unofficial languages. For the majority of these languages, this right has not been upheld. This year, 2019, the year of indigenous languages, many linguistic communities are decrying abandonment, apathy and a lack of real commitment to achieving the goals that the so-called bilingual schools are formally pursuing. It is an honour for us to be able to include contributions from the specialists we have called upon, who have generously responded with their original insights for this publication. This will help it to continue to stimulate development among the most vulnerable groups in society and particularly among communities of speakers of indigenous languages. The first half of the book contains more general contributions about linguistic diversity and its challenges as it relates to sustainable development. It includes theorising and reflections that, even if they take inspiration from knowledge and analysis of specific situations, provide information and suggestions for action to take which are relevant and applicable to any situation where there is a decline or a threat to linguistic diversity. The second half of the book incorporates contributions that could also be classified as general. However, they relate more specifically to certain languages and places which are under study and proposals specifically designed for those contexts are put forward. We believe its specificity to be its most valuable asset.Esta edición se ha realizado gracias a la financiación del Gobierno Vasco /Eusko Jaurlaritza, Departamento de Cultura y Política Lingüística y de la Fundación AZKUE. The edition of this volume has been made possible through financial Support of the Basque Government, Culture and Linguistic Policy Department and the Foundation AZKU

Stern-Gerlach experiment with light: separating photons by spin with the method of A. Fresnel

In 1822 A. Fresnel described an experiment to separate a beam of light into its right- and left-circular polarization components using chiral interfaces. Fresnel's experiment combined three crystalline quartz prisms of alternating handedness to achieve a visible macroscopic separation between the two circular components. Such quartz polyprisms were rather popular optical components in XIXth century but today remain as very little known optical devices. This work shows the analogy between Fresnel's experiment and Stern-Gerlach experiment from quantum mechanics since both experiments produce selective deflection of particles (photons in case of Fresnel's method) according to their spin angular momentum. We have studied a historical quartz polyprism with eight chiral interfaces producing a large spatial separation of light by spin. We have also constructed a modified Fresnel biprism to produce smaller separations and we have examined the analogy with Stern-Gerlach apparatus for both strong and weak measurements. The polarimetric analysis of a Fresnel polyprism reveals that it acts as a spin angular momentum analyzer

Estudio socio-clínico sobre alcoholismo en el Bierzo

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Psiquiatría. Fecha de lectura: 17 de Abril de 201

Increasing signal-to-noise ratio in over-determined Mueller matrices

This work investigates how the signal-to-noise ratio (SNR) of an over-determined Mueller matrix can be improved by changing the method of calculation. Specifically, our investigation focused on comparing SNRs achieved using the vector methodology from the field of partial Mueller polarimetry, and the matrix methodology. We use experimentally derived measurements from an investigation into the time-varying signal produced by the Mueller matrix of an electro-optic Bismuth Silicon Oxide (BSO) crystal undergoing cyclical impact of a Helium plasma ionisation wave. Our findings show that the vector methodology is superior to the matrix methodology, with a maximum SNR of 7.54 versus 4.97. We put forth that the superiority of the vector methodology is due to its greater flexibility, which results in the Mueller matrix being calculated with better condition matrices, and higher levels of SNR in the intensity measurements used for calculation.</p

Nonideal optical response of liquid crystal variable retarders and its impact on their performance as polarization modulators

Liquid crystal variable retarders (LCVRs) will be used for the first time in a space instrument, the Solar Orbiter mission of the European Space Agency, as polarization states analyzers (PSAs). These devices will determine the Stokes parameters of the light coming from the Sun by temporal polarization modulation, using the so-called modulation matrix O. This is a matrix constituted by the first rows of properly selected PSA Mueller matrices. Calibrating a space instrument, in particular, finding O, is a critical point because in a spacecraft there is no possibility of physical access. Due to the huge difficulty in calibrating the complete instruments in all possible scenarios, a more complete calibration of the individual components has been done in ground in order to make extrapolations to obtain O in-flight. Nevertheless, apart from the individual calibrations, the experimental errors and nonideal effects that inhibit the system to reach the designed and theoretical values must be known. In this work, description and study of these effects have been done, focusing on the nonideal effects of the LCVRs and the azimuthal misalignments between the optical components of the PSA during the mechanical assembly. The Mueller matrix of a representative LCVR has been measured and mathematically decomposed by logarithm decomposition, looking for values of circular birefringence and fast axis angle variations as a function of voltage. These effects, in the absence of other nonidealities, affect the polarimetric performance, reducing the polarimetric efficiencies in some cases until 11%. Nevertheless, in this case, they are negligible if compared to the other nonideality studied, which are the azimuthal misalignments between the PSA optical components. The study presented in this work is key to extrapolate the PSA O matrix if the expected instrumental set-point temperatures are not reached in flight and can be used for the design and implementation of other polarimetric instruments

Sum decomposition of Mueller-matrix images and spectra of beetle cuticles

International audienceSpectral Mueller matrices measured at multiple angles of incidence as well as Mueller matrix images are recorded on the exoskeletons (cuticles) of the scarab beetles Cetonia aurata and Chrysina argenteola. Cetonia aurata is green whereas Chrysina argenteola is gold-colored. When illuminated with natural (unpolarized) light, both species reflect left-handed and near-circularly polarized light originating from helicoidal structures in their cuticles. These structures are referred to as circular Bragg reflectors. For both species the Mueller matrices are found to be nondiagonal depolarizers. The matrices are Cloude decomposed to a sum of non-depolarizing matrices and it is found that the cuticle optical response, in a first approximation can be described as a sum of Mueller matrices from an ideal mirror and an ideal circular polarizer with relative weights determined by the eigenvalues of the covariance matrices of the measured Mueller matrices. The spectral and image decompositions are consistent with each other. A regression-based decomposition of the spectral and image Mueller matrices is also presented whereby the basic optical components are assumed to be a mirror and a circular polarizer as suggested by the Cloude decomposition. The advantage with a regression decomposition compared to a Cloude decomposition is its better stability as the matrices in the decomposition are determined a priori. The origin of the depolarizing features are discussed but from present data it is not possible to conclude whether the two major components, the mirror and the circular polarizer are laterally separated in domains in the cuticle or if the depolarization originates from the intrinsic properties of the helicoidal structure.-matrix characterization of bee-tle cuticle: polarized and unpolarized reflections from representative architectures," Appl. Opt. 49, 4558–4567 (2010).-induced polarization effects in the cuticle of scarab beetles: 100 years after Michelson," Phil. Mag. 92, 1583–1599 (2012). 4. H. Arwin, T. Berlind, B. Johs, and K. Järrendahl, "Cuticle structure of the scarab beetle Cetonia aurata analyzed by regression analysis of Mueller-matrix ellipsometric data," Opt. Express 21, 22645–22656 (2013). 5. matrices: how to decompose them?," Phys. Status Solidi A 205, 720–727 (2008). 6. S. R. Cloude, "Group theory and polarization algebra," Optik (Stuttgart) 75, 26–36 (1986). 7. S. R. Cloude and E. Pottier, "A review of target decomposition theorems in radar polarimetry," IEEE Trans

Fast and optimal broad-band Stokes/Mueller polarimeter design by the use of a genetic algorithm

A fast multichannel Stokes/Mueller polarimeter with no mechanically moving parts has been designed to have close to optimal performance from 430-2000 nm by applying a genetic algorithm. Stokes (Mueller) polarimeters are characterized by their ability to analyze the full Stokes (Mueller) vector (matrix) of the incident light. This ability is characterized by the condition number, $\kappa$, which directly influences the measurement noise in polarimetric measurements. Due to the spectral dependence of the retardance in birefringent materials, it is not trivial to design a polarimeter using dispersive components. We present here both a method to do this optimization using a genetic algorithm, as well as simulation results. Our results include fast, broad-band polarimeter designs for spectrographic use, based on 2 and 3 Ferroelectric Liquid Crystals, whose material properties are taken from measured values. The results promise to reduce the measurement noise significantly over previous designs, up to a factor of 4.5 for a Mueller polarimeter, in addition to extending the spectral range.Comment: 10 pages, 6 figures, submitted to Optics Expres

Depolarizing metrics for plant samples imaging

Optical methods, as fluorescence microscopy or hyperspectral imaging, are commonly used for plants visualization and characterization. Another powerful collection of optical techniques is the so-called polarimetry, widely used to enhance image contrast in multiple applications. In the botanical applications framework, in spite of some works have already highlighted the depolarizing print that plant structures left on input polarized beams, the potential of polarimetric methods has not been properly exploited. In fact, among the few works dealing with polarization and plants, most of them study light scattered by plants using the Degree of Polarization (DoP) indicator. Other more powerful depolarization metrics are nowadays neglected. In this context, we highlight the potential of different depolarization metrics obtained using the Mueller matrix (MM) measurement: the Depolarization Index and the Indices of Polarimetric Purity. We perform a qualitative and quantitative comparison between DoP- and MM-based images by studying a particular plant, the Hedera maroccana. We show how Mueller-based metrics are generally more suitable in terms of contrast than DoP-based measurements. The potential of polarimetric measurements in the study of plants is highlighted in this work, suggesting they can be applied to the characterization of plants, plant taxonomy, water stress in plants, and other botanical studies