Earnings Mobility in Argentina, Mexico, and Venezuela: Testing the Divergence of Earnings and the Symmetry of Mobility Hypotheses

This paper examines changes in individual earnings during positive and negative growth periods in three Latin American economies: Argentina, Mexico, and Venezuela. We ask whether those individuals who start in the best economic position are those who experience the largest earnings gains or the smallest earnings losses; this is the “divergent mobility” hypothesis. We also compare periods of positive economic growth with those of negative economic growth, asking whether those groups of individuals that experience large positive earnings gains when the economy is growing are the same as those that experience large earnings losses when the economy is contracting; this is the “symmetry of mobility” hypothesis. We find very occasional support for the divergent mobility hypothesis in scattered years in the cases of Mexico and Venezuela, and no support at all in the case of Argentina. Rather, earnings mobility is most frequently convergent or neutral in all three countries. As for the symmetry of mobility hypothesis, we find that it is rejected in most cases; rather, those groups that gain the most when the economy is growing are also the ones that gain the most when the economy is contracting. Furthermore, we explain how the absence of divergence is compatible with rising inequality in the countries under study

Income Mobility in Latin America

[Excerpt] In the last decades Latin American countries have experienced substantial macroeconomic instability. While the region as a whole experienced economic growth during most of the 1990’s and 2000’s, there were also years of stagnation as well as economic decline

Design of novel aqueous two-phase systems to be coupled in biological remediation processes

The ability of a biodegradable Deep Eutectic Solvent (DES) reline to induce phase segregation in aqueous solutions of polymeric non-ionic surfactants (Tween 20 and Tween 80) has been demonstrated as a preliminary step to be employed for assisting a biological degradation process of a model contaminant. The binodal curves for systems composed of (surfactants + reline + Water) have been determined at several temperatures, and the experimental data have been correlated using well-known equations. The equilibrium data have been analysed in the light of the operating temperature and the hydrophobicity of surfactants. Tie-lines of these systems have been determined, together with useful parameters such as tie-line length and tie-line slopes. Othmer-Tobias and Bancroft equations have been applied to provide an adequate description of the equilibrium data. Finally, the application of this new approach for the remediation of aqueous polluted effluent has proven to be highly efficient, with extraction percentages exceeding 99% for two model persistent contaminants (Acid Black 48 and Crystal Violet). Consequently, this ATPS is proposed as an extra-stage to enhance the remediation percentagesachieved through biological methods. Furthermore, the process has been simulated using commercial software.Universidade de Vigo/CISU

El profesorado universitario ante la e-evaluación del aprendizaje

El artículo se enmarca en el campo de la eevaluación en la Universidad. Se pretende identificar cómo se gestiona el proceso de evaluación de los estudiantes y, a la vez, conocer la actitud de los docentes universitarios hacia la incorporación de las tecnologías en el proceso de evaluación de aprendizajes. La metodología descriptiva-correlacional empleada se basa en la aplicación de una encuesta electrónica a una muestra representativa por rama y categoría profesional de docentes en la Universidad de Salamanca. Los resultados obtenidos, tras la realización de los contrastes inferenciales oportunos de “actitud” por rama de conocimiento, categoría profesional y años de docencia, muestran diferencias estadísticamente significativas por rama de conocimiento

Cycloidal Domains in the Magnetization Reversal Process of Ni80Fe20/Nd16Co84/Gd12Co88 Trilayers

The magnetization reversal of each individual layer in magnetic trilayers ( permalloy / Nd Co / Gd Co ) is investigated in detail with x-ray microscopy and micromagnetic calculations. Two sequential inversion mechanisms are identified. First, magnetic vortex-antivortex pairs move along the field direction while inverting the magnetization of magnetic stripes until they are pinned by defects. The vortex-antivortex displacements are reversible within a field interval which allows their controlled motion. Second, as the reversed magnetic field increases, cycloidal domains appear in the permalloy layer as a consequence of the dissociation of vortex-antivortex pairs due to pinning. The field range where magnetic vortices and antivortices are effectively guided by the stripe pattern is of the order of tens of mT for the Ni Fe layer, as estimated from the stability of cycloid domains in the sample

Spark plasma sintering and optical properties of Tm3+ and Tm3+ /Yb3+ doped NaLaF4 transparent glass-ceramics

Tm3+ doped oxyfluoride glass-ceramics (GCs) containing NaLaF4 nanocrystals (NCs) have been obtained by spark plasma sintering (SPS). First, the precursor glasses were melted and then milled and sieved to a suitable particle size. Glass powder pellets were sintered by spark plasma sintering under vacuum conditions. The SPS processing parameters (temperature, pressure, and holding time) were optimized to obtain transparent glass-ceramics. The times of SPS processing are considerably shorter compared with those for the preparation of these GCs by conventional thermal treatment. All glass-ceramics contain nanocrystals of the β- NaLaF4 phase with an average crystal size of 20 nm, but the more highly doped samples (2Tm3+ and 0.5Tm3+/2Yb3+) show evidence of the presence of another phase corresponding with α-NaLaF4. The luminescence properties of the near infrared (NIR) emissions of Tm3+ for different concentrations reveal the presence of concentration quenching of the 3H4 and 3F4 levels. The analysis of the decay from the 3H4 level with increasing concentration is consistent with a dipole-dipole quenching process assisted by energy migration, whereas the self-quenching of the 3F4→3H6 emission can be attributed to fast diffusion. Energy transfer between Yb3+ and Tm3+ ions is confirmed by the NIR and upconverted (UC) emissions after Yb3+ excitation at 975 nm. No UC emission is observed under 791 nm excitation of Tm3+ ions.Funding from MICINN under project PID2020–115419 GB-C-21/C-22/AEI/10.13039/501100011033 is acknowledged. This paper is part of the dissemination activities of project FunGlass. This project has received funding from the European Union´s Horizon 2020 research and innovation program under grant agreement No 739566

GRB 051221A and Tests of Lorentz Symmetry

Various approaches to quantum gravity suggest the possibility of violation of Lorentz symmetry at very high energies. In these cases we expect a modification at low energies of the dispersion relation of photons that contains extra powers of the momentum suppressed by a high energy scale. These terms break boost invariance and can be tested even at relatively low energies. We use the light curves of the very bright short Gamma-Ray Burst GRB 051221A and compare the arrival times of photons at different energies with the expected time delay due to a modified dispersion relation. As no time delay was observed, we set a lower bound of 0.0066 E_{pl} \sim 0.66 10^{17} GeV on the scale of Lorentz invariance violation.Comment: 9 pages, 2 figure

Cuantificación simultánea de colorantes en bebidas deportivas utilizando espectroscopia visible y PLS-1

En este trabajo se propone un nuevo procedimiento para la cuantificación de cuatro colorantes artificiales: rojo allura, azul brillante, tartrazina y amarillo ocaso, presentes en bebidas hidratantes de la marca Gatorade y Powerade. Se aplico espectroscopía visible y calibración multivariada. Los datos fueron tratados con el programa Matlab y la rutina MVC1 aplicando el método PLS-1. Los resultados de las predicciones aplicando este nuevo método, se compararon estadísticamente con los obtenidos aplicando el método de referencia (cromatografía líquida), en todos los casos los resultados fueron comparables. La desventaja es que el amarillo ocaso no pudo ser cuantificado por este método, aunque su presencia no interfiere con la determinación de los otros tres colorantes. Puede concluirse que este método es fácilmente aplicable para el control de calidad de colorantes en bebidas comerciales en laboratorios de baja complejidad, sin necesidad de recurrir a técnicas separativas y reactivos contaminantes.Fil: Rodríguez, María Celeste. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Schenone, Agustina Violeta. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe; ArgentinaFil: Sobrero, M. S.. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Marsili, N. R. . Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentin

A Code for Simulating Heat Transfer in Turbulent Channel Flow

[EN] One numerical method was designed to solve the time-dependent, three-dimensional, incompressible Navier-Stokes equations in turbulent thermal channel flows. Its originality lies in the use of several well-known methods to discretize the problem and its parallel nature. Vorticy-Laplacian of velocity formulation has been used, so pressure has been removed from the system. Heat is modeled as a passive scalar. Any other quantity modeled as passive scalar can be very easily studied, including several of them at the same time. These methods have been successfully used for extensive direct numerical simulations of passive thermal flow for several boundary conditions.This work was supported by RTI2018-102256-B-I00 of MINECO/FEDER. The computations of the new simulations were made possible by several generous grants of computing time from the Barcelona Supercomputing Centre, references FI-2018-1-0037, FI-2018-2-0021, FI-2018-3-0032, FI-2019-1-0025, IM-2019-2-2016, AECT-2020-1-0024, AECT-2020-2-0005.Lluesma-Rodríguez, F.; Alcántara-Ávila, F.; Pérez Quiles, MJ.; Hoyas, S. (2021). A Code for Simulating Heat Transfer in Turbulent Channel Flow. Mathematics. 9(7):1-12. https://doi.org/10.3390/math9070756S1129

Mejoramiento en la eficiencia del proceso de secado convencional y homogenización en el color de la Albura y el Duramen en madera de Teca (Tectona grandis L.) (Documento I)

Informe final de Proyecto de Investigación. Código: 5401-1401-1030Different drying schedules were investigated to decrease drying time of Tectona grandis L. wood from juvenile plantations, using the drying rate (DR) to reduce time. The DR value was 20% per day during the first stages and by the time the wood reached 30% of moisture content (MC), the DR remained in 8% per day until the end of drying. The initial moisture content (MCi) ranged between 92 and 115%, MCi was affected by grain pattern and heartwood percentage. The final moisture content (MCf) differed in 2.0% in relation to the MC targeted for this study. Drying time can be reduced from 140 hours to 105 hours, maintaining DR conditions and saving 33% of energy consumption. DR is affected by moisture content and drying time and this behavior can be modeled mathematically by the equation Y = a*t + b. In these relations, the factors with greatest influence were dry-bulb temperature and wet-bulb depression. Both relations show an inflexion point in the relation DR-MC, 80% in fast drying schedule and 40% in slow drying schedule. This MC indicates the point where the DR must be changed