La Investigación En La Práctica Pedagógica De Los Docentes De Educación Media

La investigación docente no debe estar limitada a campos específicos de las universidades, por el contrario, es pertinente que los docentes en todos los niveles educativos del sistema escolar, apoyen su práctica pedagógica con la realización de estudios que sistematicen sus experiencias y contribuyan al campo de la educación. El presente artículo exhibe los desarrollos de la tesis doctoral Aproximación Teórica a la Investigación en la Práctica Pedagógica de los Docentes de Educación Media, para el cual se asume una visión epistemológica constructivista, con metodología hermenéutico dialéctica, bajo el paradigma cualitativo y se sigue el método de la teoría fundamentada para el análisis de datos y la generación teórica. El estudio concluye con la presentación de la aproximación teórica según el constructo emergente que se revela en relación a la investigación en la práctica pedagógica de los docentes de educación media

Non-degenerate four-wave mixing in rubidium vapor: transient regime

We investigate the transient response of the generated light from Four-Wave Mixing (FWM) in the diamond configuration using a step-down field excitation. The transients show fast decay times and oscillations that depend on the detunings and intensities of the fields. A simplified model taking into account the thermal motion of the atoms, propagation, absorption and dispersion effects shows qualitative agreement with the experimental observations with the energy levels in rubidium (5S1/2, 5P1/2, 5P3/2 and 6S1/2). The atomic polarization comes from all the contributions of different velocity classes of atoms in the ensemble modifying dramatically the total transient behavior of the light from FWM.Comment: 11 pages, 11 figures, to be published in Physical Review

Displaced geostationary orbit design using hybrid sail propulsion

Because of an increase in the number of geostationary spacecraft and the limits imposed by east–west spacing requirements, the geostationary orbit is becoming congested. To increase its capacity, this paper proposes to create new geostationary slots by displacing the geostationary orbit either out of or in the equatorial plane by means of hybrid solar sail and solar electric propulsion. To minimize propellant consumption, optimal steering laws for the solar sail and solar-electric-propulsion thrust vectors are derived and the performance in terms of mission lifetime is assessed. For comparison, similar analyses are performed for conventional propulsion, including impulsive and pure solar electric propulsion. It is shown that hybrid sails outperform these propulsion techniques and that out-of-plane displacements outperform in-plane displacements. The out-of-plane case is therefore further investigated in a spacecraft mass budget to determine the payload mass capacity. Finally, two transfers that enable a further improvement of the performance of hybrid sails for the out-of-plane case are optimized using a direct pseudospectral method: a seasonal transit between orbits displaced above and below the equatorial plane and a transit to a parking orbit when geostationary coverage is not needed. Both transfers are shown to require only a modest propellant budget, outweighing the improvements they can establish

Experiences Participating in Online Synchronous Lectures During COVID-19 Emergency Remote Teaching for First- and Non-First-Generation Students

Background: During the COVID-19 pandemic, emergency remote teaching (ERT) was implemented in the U.S., and some of the most vulnerable college students struggled to adapt. Purpose: The current study sought to understand the experiences and outcomes of undergraduate students enrolled in radiography programs while participating in synchronous online lectures during ERT, especially first-generation students. Specifically, this study focused on students who participated in class lectures that were taught online in a live and synchronous format due to COVID-19 stay-at-home orders. Methods: This study utilized a retrospective and longitudinal design where participants were asked to answer a series of questions retrospectively at two points in time with each question forming a pair. Survey participants were enrolled as students during ERT in 2020 through 2021 and participated in class lectures that were taught online in a live and synchronous format due to COVID-19 stay-at-home orders. Results: Wilcoxon Signed-Rank and Spearman Rank-Order tests suggest that ERT has affected the experiences and outcomes of students enrolled in radiography programs, with more pronounced negative effects for first-generation students. Conclusion and Recommendations: The researchers recommend yearly and preventative planning across three academic and administrative areas to include training, support, and technology as essential strategies for delivering remote education, specifically online synchronous lectures, in the context of ERT situations. Strategies in these three areas will keep the academic success of the most vulnerable and underserved college student populations at the forefront during emergency remote teaching scenarios

Stability of axially symmetric magnetic fields in stars

The magnetic fields observed in Ap-stars, white dwarfs, and neutron stars are known to be stable for long times. However, the physical conditions inside the stellar interiors that allow these states are still a matter of research. It has been formally demonstrated that both purely toroidal and purely poloidal magnetic fields develop instabilities at some point in the star. On the other hand, numerical simulations have proved the stability of roughly axisymmetric magnetic field configurations inside stably stratified stars. These configurations consist of mutually stabilizing toroidal and poloidal components in a twisted torus shape. Previous studies have proposed rough upper and lower bounds on the ratio of the magnetic energy in the toroidal and poloidal components of the magnetic field. With the purpose of mapping out the parameter space under which such configurations remain stable, we used the Pencil Code to perform 3D magnetohydrodynamic simulations of the evolution of the magnetic field in non-rotating, non-degenerate stars in which viscosity is the only dissipation mechanism, both for stars with a uniform (barotropic) and radially increasing (stably stratified) specific entropy. Furthermore, we considered different conditions regarding the degree of stable stratification and the magnetic energy in each component, roughly confirming the previously suggested stability boundaries for the magnetic field.Comment: 9 pages, 9 figure

Construcción de la integral por recorrido para la teoría de Dirac a través de las transformaciones de Fourier de las funciones de Green

Una estructura de la integral por recorrido para el electrón relativista es propuesta en este trabajo. En la construcción de esta integral es utilizada la ecuación de Einstein-Smolukhovski y las transformaciones de Fourier para cada una de las funciones de Green. Se hace un análisis de esta integral para tres, cuatro y N puntos fijos en la trayectoria del electrón

Generation of two-photon EPR and Wstates

In this paper we present a scheme for generation of two-photon EPR and W states in the cavity QED context. The scheme requires only one three-level Rydberg atom and two or three cavities. The atom is sent to interact with cavities previously prepared in vacuum states, via two-photon process. An appropriate choice of the interaction times one obtains the mentioned state with maximized fidelities. These specific times and the values of success probability and fidelity are discussed.Comment: 4 pages, 5 figure