Propagation of gravity waves and spread F in the low-latitude ionosphere over Tucumán, Argentina, by continuous Doppler sounding: first results

Results of systematic analysis of propagation directions and horizontal velocities of gravity waves (GWs) and spread F structures in low-latitude ionosphere (magnetic inclination ~27°) in Tucumán region, Argentina, are presented. Measurements were carried out by multipoint continuous Doppler system during 1 year from December 2012 to November 2013. It was found that meridian propagation of GWs dominated and that southward propagation prevailed in the local summer. Oblique spread structures observed in Doppler shift spectrograms and associated with spread F propagated roughly eastward at velocities from ~70 to ~180 m/s and were observed at night from ~ September to ~ March. The velocities were computed for 182 events and the azimuths for 64 events. Continuous Doppler sounding makes it possible to analyze more events compared to optical observations often used for propagation studies since the measurements do not depend on weather.Fil: Chum, J.. Institute of Atmospheric Physics; República ChecaFil: Miranda Bonomi, Fernando Alberto. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Electricidad, Electrónica y Computación. Laboratorio de Telecomunicaciones; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fišer, J.. Institute of Atmospheric Physics; República ChecaFil: Cabrera, M. A.. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Electricidad, Electrónica y Computación. Laboratorio de Telecomunicaciones; Argentina. Universidad Tecnológica Nacional. Facultad Regional Tucuman; ArgentinaFil: Ezquer, Rodolfo Gerardo. Universidad Tecnológica Nacional. Facultad Regional Tucuman; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Ionosfera; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Burešová, D.. Institute of Atmospheric Physics; República ChecaFil: Laštovička, J.. Institute of Atmospheric Physics; República ChecaFil: Baše, J.. Institute of Atmospheric Physics; República ChecaFil: Hruška, F.. Institute of Atmospheric Physics; República ChecaFil: Molina, Maria Graciela. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Ciencias de la Computación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ise, Juan Eduardo. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Electricidad, Electrónica y Computación. Laboratorio de Telecomunicaciones; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cangemi, José Ignacio. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Electricidad, Electrónica y Computación. Laboratorio de Telecomunicaciones; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Šindelářová, T.. Institute of Atmospheric Physics; República Chec

Climate of the upper atmosphere

In the frame of the European COST 296 project (Mitigation of Ionospheric Effects on Radio Systems, MIERS)investigations of the climate of the upper atmosphere have been carried out during the last four years to obtain new information on the upper atmosphere. Mainly its ionospheric part has been analysed as the ionosphere is most essential for the propagation of radio waves. Due to collaboration between different European partners many new results have been derived in the fields of long-term trends of different ionospheric and related atmospheric parameters, the investigations of different types of atmospheric waves and their impact on the ionosphere, the variability of the ionosphere, and the investigation of some space weather effects on the ionosphere.Published273-2991.7. Osservazioni di alta e media atmosferaJCR Journalreserve

Ionospheric Response at Conjugate Locations During the 7–8 September 2017 Geomagnetic Storm Over the Europe-African Longitude Sector

This paper focuses on unique aspects of the ionospheric response at conjugate locations over Europe and South Africa during the 7–8 September 2017 geomagnetic storm including the role of the bottomside and topside ionosphere and plasmasphere in influencing electron density changes. Analysis of total electron content (TEC) on 7 September 2017 shows that for a pair of geomagnetically conjugate locations, positive storm effect was observed reaching about 65% when benchmarked on the monthly median TEC variability in the Northern Hemisphere, while the Southern Hemisphere remained within the quiet time variability threshold of ±40%. Over the investigated locations, the Southern Hemisphere midlatitudes showed positive TEC deviations that were in most cases twice the comparative response level in the Northern Hemisphere on the 8 September 2017. During the storm main phase on 8 September 2017, we have obtained an interesting result of ionosonde maximum electron density of the F2 layer and TEC derived from Global Navigation Satellite System (GNSS) observations showing different ionospheric responses over the same midlatitude location in the Northern Hemisphere. In situ electron density measurements from SWARM satellite aided by bottomside ionosonde-derived TEC up to the maximum height of the F2 layer (hmF2) revealed that the bottomside and topside ionosphere as well as plasmasphere electron content contributions to overall GNSS-derived TEC were different in both hemispheres especially for 8 September 2017 during the storm main phase. The differences in hemispheric response at conjugate locations and on a regional scale have been explained in terms of seasonal influence on the background electron density coupled with the presence of large-scale traveling ionospheric disturbances and low-latitude-associated processes. The major highlight of this study is the simultaneous confirmation of most of the previously observed features and their underlying physical mechanisms during geomagnetic storms through a multi–data set examination of hemispheric differences. © 2020. American Geophysical Union. All Rights Reserved

The experimental analysis of problematic video gaming and cognitive skills: a systematic review

There is now a growing literature demonstrating the excessive gaming can have negative detrimental effects on a small minority of gamers. This has led to much debate in the psychological literature on both the positive and negative effects of gaming. One specific area that has been investigated is the effect of gaming on different types of cognitive skills. The present study carried a systematic review examining the studies that have examined the impact of problematic gaming on cognitive skills. Following a number of inclusion and exclusion criteria, a total of 18 studies were identified that had investigated three specific cognitive skills: (i) multi-second time perception (4 studies), inhibition (7 studies), and decision-making (7 studies). Based on the studies reviewed, the findings demonstrate that the pathological and/or excessive use of videogames leads to more negative consequences on cognitive processes. Contexte et objectifs: Jouer aux jeux vidéo est devenu l’une des activités mondiales majeures avec des millions de personnes y jouant tous les jours. Suivant ce succès, les jeux vidéo ont grandement évolué, multipliant les genres (p.ex., MMORPG, MOBA, FPS); certains de ces jeux demandant un grand investissement de la part des joueurs. Cet investissement peut devenir excessif, voire pathologique, et de nombreuses études ont exploré ce risque, menant à l’inclusion de l’« Usage pathologique des jeux sur Internet » dans l’appendice du DSM-5 (American Psychiatric Association, 2013). Cependant, malgré les risques sous-jacents d’une addiction (p.e.x., pertes de relations, difficultés scolaires), il a également été démontré que le jeu vidéo pouvait significativement améliorer les performances des joueurs (p.ex., performances sur un simulateur de chirurgie, Fanning, Fenton, Johnson, Johnson, & Rehman, 2011; meilleure recherche visuelle, Sims & Mayer, 2002). De plus, il a été démontré que le fait de jouer à ces jeux pouvait impacter les capacités cognitives des joueurs (p.ex., Durlach, Kring, & Bowens, 2009). Une revue systématique sur l’impact d’une utilisation pathologique/excessive sur ces capacités a donc été menée. Méthode: La recherche d’articles a été menée sur quatre bases de données (p.ex., Google Scholar, PubMed, Science Direct, PsychINFO). Afin d’être inclus dans cette revue, les articles revus par les pairs devaient: (i) dater d’au moins 2000 (les jeux vidéo ayant grandement évolué depuis), (ii) inclure au moins une étude expérimentale sur les processus cognitifs des joueurs, (iii) inclure des joueurs excessifs/pathologiques, (iv) être publiés en anglais, et (v) Ne pas avoir été utilisés dans une revue de littérature auparavant (p.ex., études en fMRI). Après sélection des articles et tri des doublons, la recherche a mené à 18 résultats dans 3 sections différentes (c.-à-d., Perception du temps supérieur à la seconde, Inhibition, et Prise de décision). Résultats: Les expériences sur la perception du temps montrent des résultats hétérogènes, certaines études ne montrant aucun résultat (p.ex.., Rivero, Covre, Reyes, & Bueno, 2012), d’autres des résultats partiels (Rau, Peng, & Yang, 2006), voire des résultats significatifs (Tobin & Grondin, 2009). Cependant, les études démontrant des résultats (potentiellement) significatifs incluaient des utilisateurs pathologiques, contrairement aux études sans résultats significatifs. Cette différence de population pouvant potentiellement expliquer cette différence. Les études sur l’inhibition montrent le même type de résultats hétérogènes, cependant, une fois ces études classées par type d’inhibition, il apparaîtrait que les joueurs montrent une inhibition de la réponse prépotente réduite (p.ex., au travers de tâches Go/Nogo, Littel et al., 2012), celle-ci étant aggravée lorsque des stimuli liés aux jeux étaient inclus dans la tâche (p.ex., Liu et al., 2014). Cependant, la seule étude ayant exploré l’annulation d’une réponse prépotente n’a pas démontré d’inhibition réduite, les joueurs de jeux-vidéos d’action présentant des temps de réactions réduits (Colzato, van den Wildenberg, Zmigrod, & Hommel, 2013). Finalement, Les études sur la prise de décision montrent des résultats similaires au travers des études, c’est-à-dire des lacunes à prendre des décisions dans des contextes de risque (p.ex., Pawlikowski & Brand, 2011), une prise de décision intacte dans les tâches à contextes ambigus (p.ex., Nuyens et al., 2016), et une tendance à préférer une récompense moindre immédiate à une récompense plus importante après un délai variable (Weinstein, Abu, Timor, & Mama, 2016). Discussion: Malgré les divers résultats contraires, et le peu d’étude sur certains processus, il est clair qu’une utilisation pathologique des jeux vidéo peut mener à des difficultés cognitives. Cependant, sachant que les études sur les performances susmentionnées ne recrutaient que des participants sains, il est supposable qu’une utilisation normale mènerait à des performances améliorées, sans aucune contrepartie négative. Plus d’études seraient donc nécessaires afin de déterminer l’impact différent des jeux vidéo sur les processus cognitifs en fonction du degré et type d’utilisation de ceux-ci (c.-à-d., utilisation occasionnelle, fréquente, ou pathologique)

Hysteresis of <i>fo</i>F2 at European middle latitudes

The hysteresis of foF2 is studied for several European stations over the whole 24-hour diurnal interval for the equinoctial months of the years just before and just after the solar cycle minimum for solar cycles 20 and 21. Based on previous results, the hysteresis is expected to develop best just for the equinoctial months and near the solar cycle minimum. The hysteresis is generally found to be negative, i.e. higher foF2 for the rising branch compared to the falling branch of solar cycle. However, this is not the case in some individual months of some years. The noontime hysteresis represents the hysteresis at other times of the day qualitatively (as to sign) but not quantitatively. The hysteresis appears to be relatively persistent from one solar cycle to another solar cycle in spring but not in autumn. A typical value for springtime hysteresis is about 0.5 MHz. The inclusion of hysteresis into long-term ionospheric and radio wave propagation predictions remains questionable.Key words: Ionosphere (mid-latitude ionosphere; ionospheric disturbances

November 2003 event: effects on the Earth's ionosphere observed from ground-based ionosonde and GPS data

Intense late-cycle solar activity during October and November 2003 produced two strong geomagnetic storms: 28 October-5 November 2003 (October) and 19-23 November 2003 (November); both reached intense geomagnetic activity levels, <i>K_p</i>=9, and <i>K_p</i>=8+, respectively. The October 2003 geomagnetic storm was stronger, but the effects on the Earth's ionosphere in the mid-latitude European sector were more important during the November 2003 storm. The aim of this paper is to discuss two significant effects observed on the ionosphere over the mid-latitude European sector produced by the November 2003 geomagnetic storm, using data from ground ionosonde at Chilton (51.5&deg; N; 359.4&deg; E), Pruhonice (50.0&deg; N; 14.6&deg; E) and El Arenosillo (37.1&deg; N; 353.3&deg; E), jointly with GPS data. These effects are the presence of well developed anomalous storm <i>E_s</i> layers observed at latitudes as low as 37&deg; N and the presence of two thin belts: one having enhanced electron content and other, depressed electron content. Both reside over the mid-latitude European evening sector