TIC en la profesionalización docente: Necesidades formativas y de contexto identificados en un curso de Didáctica Universitaria.

Se percibe que muchos docentes y futuros docentes universitarios, están disconformes con las propuestas formativas sobre TIC en Educación Superior. Puede encontrarse profesores universitarios, poco capaces de utilizar la tecnología disponible para desarrollar competencias profesionales y humanas. El objetivo de este trabajo es analizar las necesidades formativas y de contexto en el módulo TIC, correspondiente a la Especialización en Didáctica Superior Universitaria en una institución privada de Paraguay. Este estudio tiene el propósito de aportar insumos para proponer acciones, en pos de atender necesidades formativas y de contexto de estudiantes de postgrado en Didáctica Universitaria, en referencia al aprovechamiento de TIC. La contribución de esta investigación, es la propuesta formativa para docentes y futuros docentes universitarios, que invita al desarrollo de capacidades específicas sobre TIC, operacionalizando en temas puntuales, los estándares de UNESCO sobre competencias tecnológicas paradocentes.CONACYT - Consejo Nacional de Ciencia y TecnologíaPROCIENCI

Searching for tidal tails around ω\omega Centauri using RR Lyrae Stars

We present a survey for RR Lyrae stars in an area of 50 deg$^2$ around the globular cluster $\omega$ Centauri, aimed to detect debris material from the alleged progenitor galaxy of the cluster. We detected 48 RR Lyrae stars of which only 11 have been previously reported. Ten among the eleven previously known stars were found inside the tidal radius of the cluster. The rest were located outside the tidal radius up to distances of $\sim 6$ degrees from the center of the cluster. Several of those stars are located at distances similar to that of $\omega$ Centauri. We investigated the probability that those stars may have been stripped off the cluster by studying their properties (mean periods), calculating the expected halo/thick disk population of RR Lyrae stars in this part of the sky, analyzing the radial velocity of a sub-sample of the RR Lyrae stars, and finally, studying the probable orbits of this sub-sample around the Galaxy. None of these investigations support the scenario that there is significant tidal debris around $\omega$ Centauri, confirming previous studies in the region. It is puzzling that tidal debris have been found elsewhere but not near the cluster itself.Comment: 11 pages, 11 figures, Accepte

Close encounters involving RAVE stars beyond the 47 Tucanae tidal radius

The most accurate 6D phase-space information from the Radial Velocity Experiment (RAVE) was used to integrate the orbits of 105 stars around the galactic globular cluster 47 Tucanae, to look for close encounters between them in the past, with a minimum distance approach less than the cluster tidal radius. The stars are currently over the distance range 3.0 kpc $<$ d $<$ 5.5 kpc. Using the uncertainties in the current position and velocity vector for both, star and cluster, 105 pairs of star-cluster orbits were generated in a Monte Carlo numerical scheme, integrated over 2 Gyr and considering an axisymmetric and non-axisymmetric Milky-Way-like Galactic potential, respectively. In this scheme, we identified 20 potential cluster members that had close encounters with the globular cluster 47 Tucanae, all of which have a relative velocity distribution (V$_{rel}$) less than 200 km s$^{-1}$ at the minimum distance approach. Among these potential members, 9 had close encounters with the cluster with velocities less than the escape velocity of 47 Tucanae, therefore a scenario of tidal stripping seems likely. These stars have been classified with a 93\% confidence level, leading to the identification of extratidal cluster stars. For the other 11 stars, V$_{rel}$ exceeds the escape velocity of the cluster, therefore they were likely ejected or are unassociated interlopers.Comment: 10 pages, 6 figures, 2 table, Accepted for publication in MNRA

Treinta y cinco años de investigación en gestión estratégica. Un análisis de países utilizando técnicas bibliométricas para el período 1987-2021

[EN] As a significant field of study, thirty-five years of strategic management research has accumulated a substantial amount of knowledge. This bibliometric study explores whether the unlimited flow of knowledge and the globalization of education & research in this time period, could drive away (or deter) the identification and specific interest of research in phenomena of national importance. Using bibliometric techniques and visualization of similarities (VOS) procedures of citation and co-citation analyses, this Paper explores research trends at the country level over 35 years using data from the Web of Science database. The aims are to identify: 1) the most visible and prominent actors at the country, regional, and global-level; 2) the evolution of the subjects of research into strategic management at the country, global, and supra-regional level; and 3) the evolution of journals publishing strategic management research articles by location. Findings suggest that common research subjects coexist at higher levels of aggregation, establishing the “paradigm” or general agreement about the field’s boundaries. Additionally, findings show that at the country level, rather than following a global trend, there is an enduring diversification of research agendas that bow to national and supranational factors from geographically close places.[ES] Como un campo de estudio importante, treinta y cinco años deinvestigación en gestión estratégica han acumulado una cantidad sustancial deconocimiento. Este estudio bibliométrico explora si el flujo ilimitado deconocimiento y la globalización de la educación y la investigación en esteperíodo de tiempo, podría alejar (o disuadir) la identificación y el interésespecífico de investigación de fenómenos de importancia nacional. Utilizandotécnicas bibliométricas y procedimientos de visualización de similitudes (VOS) de análisis de citas y co-citas, este documentoexplora las tendencias de investigación a nivel de país durante 35 añosutilizando datos de la base de datos Web of Science. Los objetivos se centranen identificar: 1) los actores más visibles y destacados a nivel nacional,regional y mundial; 2) la evolución de los temas de investigación de la gestiónestratégica a nivel país, global y suprarregional; y 3) la evolución de las revistas que publicanartículos de investigación de gestión estratégica por ubicación. Los hallazgossugieren que los temas de investigación comunes coexisten en niveles superioresde agregación, estableciendo el “paradigma” o acuerdo general sobre los límitesde campo de estudio. Además, los hallazgos muestran que, a nivel de países,existe una diversificación persistente de agendas de investigación, que seinclinan a estudiar eventos nacionales y supranacionales de lugaresgeográficamente cercanos, en vez de seguir una tendencia global

Possible ring material around centaur (2060) Chiron

We propose that several short duration events observed in past stellar occultations by Chiron were produced by rings material. From a reanalysis of the stellar occultation data in the literature we determined two possible orientations of the pole of Chiron's rings, with ecliptic coordinates l=(352+/-10) deg, b=(37+/-10) deg or l=(144+/-10) deg, b=(24+/-10) deg . The mean radius of the rings is (324 +/- 10) km. One can use the rotational lightcurve amplitude of Chiron at different epochs to distinguish between the two solutions for the pole. Both imply lower lightcurve amplitude in 2013 than in 1988, when the rotational lightcurve was first determined. We derived Chiron's rotational lightcurve in 2013 from observations at the 1.23-m CAHA telescope and indeed its amplitude is smaller than in 1988. We also present a rotational lightcurve in 2000 from images taken at CASLEO 2.15-m telescope that is consistent with our predictions. Out of the two poles the l=(144+/-10) deg, b=(24+/-10) deg solution provides a better match to a compilation of rotational lightcurve amplitudes from the literature and those presented here. We also show that using this preferred pole, Chiron's long term brightness variations are compatible with a simple model that incorporates the changing brightness of the rings as the tilt angle with respect to the Earth changes with time. Also, the variability of the water ice band in Chiron's spectra in the literature can be explained to a large degree by an icy ring system whose tilt angle changes with time and whose composition includes water ice, analogously to the case of Chariklo. We present several possible formation scenarios for the rings from qualitative points of view and speculate on the reasons why rings might be common in centaurs. We speculate on whether the known bimodal color distribution of centaurs could be due to presence of rings and lack of them

Madera de compresión en Pinus radiata D. Don: I, características anatómicas

Se caracterizó la madera de compresión en 10 árboles de Pinus radiata D.Don con inclinaciones menores a 10 º en dos sitios.Los diámetros de traqueidas de los árboles del sitio Arena húmeda resultaron estadísticamente mayores que los del sitio Arcilla; pero no resultaron diferentes al comparar madera juvenil y madura o al comparar madera de compresión con madera opuesta.Diferencias significativas se determinaron en el largo de traqueida entre sitios (Arena húmeda-Arcilla), tipo de madera (madera de compresión-opuesta) y edad (madera juvenil-madura), resultados coincidentes con otros autores.Para el coarseness diferencias no significativas entre sitios, así como entre madera juvenil y madura y entre madera de compresión y opuesta coinciden y difieren de los de otros autores que comparan árboles de distintos sitios.Las discrepancias y coincidencias de estos resultados con los de otros autores se explican considerando el comportamiento diferente de las dimensiones celulares de la madera temprana y tardía y las diferencias que hay entre madera de compresión leve y la madera de compresión severa. AbstractCompression wood in 10 Pinus radiata D. Don trees with lean smaller to 10º from two sites were characterized. The tracheid diameters of the trees of the humid sand site were statistically greater than those from the clay site; but they were not different when comparing juvenile wood with mature wood or to it compares compression wood with opposite wood.Significant differences were determined in the tracheid length between sites (humid sand-clay), type of wood (compression-opposite wood) and age (juvenile-mature wood), were similar results with other authors.For coarseness non significant differences between sites, as well as between juvenile and mature wood and compression and opposite and agree and different from those of other authors who compare trees of different sites.The discrepancies and coincidences of these results with those of other authors are explained considering the behavior from the cellular dimensions of the earlywood and latewood wood and the differences between severe compression and mild compression wood

Empirical Rates Characterization of Wearable Multi-Antenna Terminals for First-Responders

Empirical characterization of the achievable rates for a wearable multi-antenna terminal shows the potential advantages of deploying a large number of antennas at the user end. We focus on the challenges and requirements of the broadband communication in future emergency communication systems, specifically addressing the outdoor-to-indoor propagation scenario, where the first responder is within an underground area such as a garage or basement. The measurement campaign undertaken characterizes the flat fading multiple-input multiple-output (MIMO) channel matrices at 3.5 GHz for a maximum of M = 30 antennas deployed at the base station (BS), and N = 12 wearable antennas at the user. The achievable rates are obtained for two transmission strategies that account for the different levels of channel knowledge. In both cases, all the MIMO processing is carried out at the BS.This work was supported in part by the Spanish Government under Project MIMOTEX (TEC2014-61776-EXP), Project CIES (RTC-2015-4213-7), and Project TERESA-ADA (TEC2017-90093-C3-2-R) (MINECO/AEI/FEDER, UE), and in part by the Chilean Government through projects CONICYT under Grant Proyecto Basal FB0821, Grant Fondecyt Iniciación 11171159, and Grant VRIEA-PUCV 039.462/2017.Publicad

Nuevos registros para el mapache, procyon lotor (carnivora: procyonidae) y el tlalcoyote, taxidea taxus (carnivora: mustelidae) en Chihuahua y Durango, México

Seven new records of Taxidea taxus (American badger) and Procyon lotor (raccoon) were documented for the northern states of Chihuahua and Durango, Mexico. Four of them are new localities for T. taxus, a species considered threatened, and 3 new locality records belongs to P. lotor. These records fill gaps in the geographical distribution of these carnivores in northern Mexico.RESUMEN. Se documentaron siete nuevos registros del tlalcoyote, Taxidea taxus y el mapache Procyon lotor, para los estados de Chihuahua y Durango, México. Cuatro de estas son nuevas localidades para T. taxus, una especie considerada amenazada, y tres son nuevas localidades para P. lotor. Estos registros llenan un vacío en la distribución geográfica de estos carnívoros en el norte de México.

Gingival crevicular fluid zinc-and aspartyl-binding protease profile of individuals with moderate/severe atopic dermatitis

Indexación ScopusAtopic dermatitis (AD) is a protease-modulated chronic disorder with heterogenous clinical manifestations which may lead to an imprecise diagnosis. To date, there are no diagnostic protease tests for AD. We explored the gingival crevicular fluid (GCF) protease profile of individuals with moderate/severe AD compared to healthy controls. An exploratory case-control study was conducted. AD patients (n = 23) and controls (n = 21) were enrolled at the International Center for Clinical Studies, Santiago, Chile. Complete dermatological and periodontal evaluations (involving the collection of GCF samples) were made. The levels of 35 proteases were analyzed using a human protease antibody array in matching AD patients (n = 6) and controls (n = 6) with healthy periodontium. The GCF levels of zinc-binding ADAM8, ADAM9, MMP8, Neprilysin/CD10, aspartyl-binding Cathepsin E, serin-binding Protein convertase9, and uPA/Urokinase proteases were lower in moderate/severe AD patients compared to controls (p < 0.05). No inter-group differences in the levels of the other 28 proteases were found. MMP8, Cathepsin E, and ADAM9 were the biomarkers with the highest sensitivity and specificity regarding the detection of AD (p < 0.05). The area under receiver operating characteristic (ROC) curve for MMP8 was 0.83 and MMP8 + ADAMP9 was 0.90, with no significant differences (p = 0.132). A combined model of MMP8, Cathepsin E, and ADAM9 was not considered since it did not converge. Then, levels of MMP8 in GCF were determined using a multiplex bead immunoassay in 23 subjects with AD and 21 healthy subjects. Lower levels of MMP8 in the GCF from the AD group versus healthy group (p = 0.029) were found. This difference remained significant after adjustment by periodontitis (p = 0.042). MMP8 revealed the diagnostic potential to identify AD patients versus healthy controls, (ROC area = 0.672, p < 0.05). In conclusion, differences in the protease profile between AD and control patients were associated with MMP8, Cathepsin E, and ADAM9. Based on the multiplex assay results, MMP8 was lower in AD patients than controls, suggesting that MMP8 may be a diagnostic biomarker candidate. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.https://www.mdpi.com/2218-273X/10/12/160