443 research outputs found
Lightning activity in the Southern Coast of Chile
Ponencia presentada en la XV International Conference on Atmospheric Electricity, 15-20 June 2014, Norman, Oklahoma, U.S.A.Based on eight years of lightning data (from January 2005 to December 2012) from the World Wide Lightning Location Network (WWLLN) we describe the spatial distribution and temporal variability of lightning activity over southern Chile. This region extends from ~ 40°S to 55°S along the west coast of South America, is limited to the east by the austral Andes about 100 km inland, and features a maritime climate with annual mean precipitation in excess of 4000 mm. Cloud electrification is not expected in this region given the predominance of stable, deep-stratiform precipitation there, but days with at least one stroke occur up to a third of the time along the coast, being slightly more frequent during late summer and fall. Lightning density and frequency of lightning days exhibit a sharp maximum along the coast of southern Chile. Disperse strokes are also observed off southern Chile. In contrast, lightning activity is virtually inexistent over the austral Andes -where precipitation is maximum- and farther east over the dry lowlands of Argentina. It is suggested that electrification could develop under weakly unstable conditions that prevail in the region after the passage of a cold front. Large-scale ascent near the cyclone?s center may lift near-surface air parcels over open ocean fostering shallow convection, which is enhanced as the strong westerly flow ascend over the coastal topography. Laboratory experiments of charge transferred during ice crystal-graupel collisions in low liquid water content conditions and low impact velocity have shown that the non-inductive mechanism can work as a charge separation process in these systems.Fil: Nicora, M. Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Departamento de Investigaciones en Láseres y sus aplicaciones; Argentina.Fil: Nicora, M. Gabriela. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Departamento de Investigaciones en Láseres y sus aplicaciones; Argentina.Fil: Quel, Eduardo J. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Departamento de Investigaciones en Láseres y sus aplicaciones; Argentina.Fil: Quel, Eduardo J. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Departamento de Investigaciones en Láseres y sus aplicaciones; Argentina.Fil: Bürgesser, Rodrigo E. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Bürgesser, Rodrigo E. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Ávila, Eldo E. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Ávila, Eldo E. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Garreaud, René D. Universidad de Chile. Department of Geophysics; ChileFil: Garreaud, René D. Center for Climate and Resilience Research; ChileInvestigación Climatológic
Decision making in fencing training and its relationship with reaction time
En la esgrima, se plantean tareas orientadas a desarrollar el mecanismo de percepción, el de decisión y/o el de ejecución. Una forma de saber en qué medida se incide más en uno u otro es medir el Tiempo de Reacción, y a partir de él hacer inferencias sobre el efecto de las variables manipuladas en la investigación sobre cada uno de los mecanismos. Por otro lado, nos puede ayudar a determinar el nivel de capacidad perceptiva y de toma de decisiones de un esgrimista. Los objetivos planteados en este estudio fueron, conocer si existen diferencias en cuanto a la percepción y toma de decisiones en función del arma practicada y determinar con qué acciones se dificulta la percepción y la toma de decisiones en esgrima. Los sujetos fueron 18 miembros del equipo nacional de esgrima, que se colocaron frente a una pantalla en la que se proyectaban vídeos en los que aparecía el entrenador de cada arma realizando acciones a las que los esgrimistas debían reaccionar lo antes posible. Los resultados mostraron diferencias significativas del grupo de espadistas con los floretistas y sablistas. Por otro lado, se pudo constatar que la tarea que más tiempo requiere para tomar la decisión al tirador es discernir si un ataque lanzado por el contrario está bien o mal ejecutado.In fencing, certain tasks are designed to develop the mechanism of perception, decision and/ or execution. One way to know the effect to one or another is to measure the Reaction Time, making inferences about the effect of the manipulated variables in the research about the mechanisms. On the other hand, Reaction Time can help us to determine the level of perceptual ability and decision making of a fencer. The objectives of this study were, test the differences in perception and decision making depending on the weapon, and determine what actions are more difficult to perception and decision making in fencing. The subjects were 18 members of the spanish national fencing team. Fencers were placed facing a screen in which videos were projecting appearing the coach of each weapon launching actions to which the fencers had to react quickly. The results showed significant differences between the epeeists and the foil and sabre fencers. On the other hand, it was found more time is required to make the decision is to distinguish if the opponent´s attack had a good or bad execution.peerReviewe
Reconstrucción de espectros de irradiancia solar global UV a partir de mediciones con radiómetro de banda angosta
La medición de la región ultravioleta (UV) de la radiación solar ha sido motivo de sumo interés desde la aparición del fenómeno de adelgazamiento global de la capa de ozono. Diferentes propuestas tecnológicas fueron utilizadas para tal fin, desde radiómetros de banda ancha, hasta los costosos espectrorradiómetros. Los radiómetros de ancho de banda moderado (típicamente 10 nm) con canales centrados en las regiones UVA y UVB, son una solución intermedia entre las dos anteriores y están ampliamente distribuidos. En este trabajo se describe un método para realizar la reconstrucción del espectro UV entre 290 y 400 nm a partir de las mediciones de un instrumento de este tipo y de la utilización conjunta de un modelo de transferencia radiativa. A partir de la reconstrucción del espectro solar UV en superficie con una resolución de 1 nm es posible monitorear la estabilidad de los distintos canales de los radiómetros a lo largo del tiempo, y también calcular diferentes subproductos, como la irradiancia eritémica y el índice UV. Se presentan resultados para instrumentos GUV de Biospherical Instruments Inc., instalados en el país. También se comparan los valores de la radiación biológicamente efectiva (irradiancia eritémica) calculada por este método con la medida directa de diferentes biómetros de la estación de sensado remoto que el CEILAP tiene instalado en el sitio SOLAR en la ciudad patagónica de Rio Gallegos.The measurement of ultraviolet (UV) solar radiation has been a subject of great interest since the emergence of the global depletion of the ozone layer phenomenon. Different technological proposals were used to this purpose, from broadband radiometers to expensive spectroradiometers.
Moderate ubandwidth uradiometers u(typically u10 unm) uwith uchannels uon uregions uUVA uand uUVB, uare ua intermediate usolution ubetween uthe utwo previous instruments, and they are widely distributed. This paper describes a method to carry out the reconstruction of the UV spectrum between 290 and 400 nm from measurements of this kind of instrument and the joint use of a radiative transfer model. From the reconstruction of UV solar spectrum in surface with a resolution of 1 nm it is possible to monitor the stability of the various channels of the radiometers over time, and also to calculate different subproducts, as erythemical irradiance and UV index. The results for GUV instruments from Biospherical Instruments Inc. installed in the country are presented. The values of biologically effective radiation (erythemical irradiance) calculated by this method with direct measurement from different biometers CEILAP has installed in the SOLAR site in the Patagonian city of Rio Gallegos, are also compared
The unusual persistence of an ozone hole over a southern mid-latitude station during the Antarctic spring 2009: a multi-instrument study
International audienceRecord-low ozone column densities (with a minimum of 212 DU) persisted over three weeks at the Río Gallegos NDACC (Network for the Detection of Atmospheric Composition Change) station (51.5° S, 69.3° W) in November 2009. Total ozone remained two standard deviations below the climatological mean for five consecutive days during this period. The statistical analysis of 30 years of satellite data from the Multi Sensor Reanalysis (MSR) database for Río Gallegos revealed that such a long-lasting low-ozone episode is a rare occurrence. The event is examined using height-resolved ozone lidar measurements at Río Gallegos, and observations from satellite and ground-based instruments. The computed relative difference between the measured total ozone and the climatological monthly mean shows reductions varying between 10 and 30% with an average decrease of 25%. The mean absolute difference of total ozone column with respect to climatological monthly mean ozone column is around 75 DU. Extreme values of the UV index (UVI) were measured at the ground for this period, with the daily maximum UVI of around 13 on 15 and 28 November. The high-resolution MIMOSA-CHIM (Modélisation Isentrope du transport Méso-échelle de l'Ozone Stratosphérique par Advection) model was used to interpret the ozone depletion event. An ozone decrease of about 2 ppmv was observed in mid-November at the 550 K isentropic level (~22 km). The position of Río Gallegos relative to the polar vortex was classified using equivalent latitude maps. During the second week of November, the vortex was over the station at all isentropic levels, but after 20 November and until the end of the month, only the 10 lower levels in the stratosphere were affected by vortex overpasses with ozone poor air masses. A rapid recovery of the ozone column density was observed later, due to an ozone rich filament moving over Río Gallegos between 18 and 24 km in the first two weeks of December 2009
La actividad eléctrica atmosférica en Argentina : estimación de la tasa de mortalidad anual por acción de caídas de rayos
Disponer de información de la actividad eléctrica en el territorio nacional es un elemento fundamental para la vigilancia atmosférica. Tanto para aplicaciones de relevancia, en cuestiones de seguridad e infraestructura, así como variable meteorológica, los valores de días de tormenta en las diferentes regiones del país, son una herramienta simple y poderosa para poder evaluar la atmósfera y losfuturos cambios en ella.Los objetivos del presente trabajo son realizar un estudio de la evolución de la eficiencia de detección de descargas eléctricas de la red global terrestre World Wide LightningLocation Network (WWLLN) dentro del territorio nacional, comparar los datos de dicha red con los datos suministrados por el SMN y, en función de la evaluación de dicha información, confeccionar los mapas isoceraúnico de la República Argentina para el periodo 2005-2012.Estos datos se utilizan para estimar la tasa de mortalidad anual por un rayo en la región. La estimación se basa en un modelo propuesto por Gomes Chandima, y Ab Kadir [1]. Los resultados obtenidos podrían ayudar a fomentar conductas de protección en la población.To have information of electrical activity in the country is a key element for atmospheric monitoring. In the fields of applications in security and infrastructure issues and weather variables, the values of stormy days in different regions of the country are a simple and powerful tool to evaluate the atmosphere and future changes. The objectives of this study are to conduct a study of the evolution of the efficiency of lightning detection global terrestrial network World Wide Lightning Location Network (WWLLN) within the country, comparing this data with the supplied by the SMN and, depending on the evaluation of that information, make isoceraunics maps of Argentina for the period 2005-2011. These data are used to estimate the annual death rate by lightning in the region. The estimation is based on a model proposed by Chandima Gomes, and AbKadir [1]. The obtained results could help to promote protective behaviors in the population.http://anales.fisica.org.ar/journal/index.php/analesafa/article/view/1995https://anales.fisica.org.ar/journal/index.php/analesafa/article/view/1995publishedVersionFil: Nicora, M. Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Departamento de Investigaciones en Láseres y sus aplicaciones; Argentina.Fil: Nicora, M. Gabriela. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Departamento de Investigaciones en Láseres y sus aplicaciones; Argentina.Fil: Quel, Eduardo J. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Departamento de Investigaciones en Láseres y sus aplicaciones; Argentina.Fil: Quel, Eduardo J. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Departamento de Investigaciones en Láseres y sus aplicaciones; Argentina.Fil: Nicora, M. Gabriela. Instituto Franco Argentino de Estudios sobre el Clima y sus Impactos; ArgentinaFil: Quel, Eduardo J. Instituto Franco Argentino de Estudios sobre el Clima y sus Impactos; ArgentinaFil: Salvador, Jacobo O. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigaciones en Láseres y Aplicaciones; Argentina.Fil: Salvador, Jacobo O. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigaciones en Láseres y Aplicaciones; Argentina.Fil: Bürgesser, Rodrigo E. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Ávila, Eldo E. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Bürgesser, Rodrigo E. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Ávila, Eldo E. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Rosales, Alejandro. Universidad Nacional de la Patagonia. Facultad de Ingeniería. Departamento de Física; ArgentinaFil: D’Elia, Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Departamento de Investigaciones en Láseres y sus aplicaciones; Argentina.Fil: D’Elia, Raúl. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Departamento de Investigaciones en Láseres y sus aplicaciones; Argentina.Fil: D’Elia, Raúl. Instituto Franco Argentino de Estudios sobre el Clima y sus Impactos; ArgentinaMeteorología y Ciencias Atmosférica
Effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness: A multi-country cluster randomized controlled trial
Purpose: To examine the effects of a school-based karate intervention on academic achievement, psychosocial functioning and physical fitness in children aged 7-8 years.
Methods: Twenty schools of five different European countries (two second grade classrooms per school) participated in the present cluster randomised controlled trial (Sport at School trial). Participants were assigned to either a control group, which continued with their habitual physical education lessons, or to an intervention group, which replaced these lessons by a one-year karate intervention (Karate Mind and Movement program). Outcomes included academic performance (average grade), psychosocial functioning (Strengths and Difficulties Questionnaire for parents), and different markers of physical fitness (cardiorespiratory fitness, balance and flexibility).
Results: Seven hundred and twenty-one children (344 girls and 377 boys, 7.4±0.5 years) completed the study, of which 333 and 388 were assigned to the control and intervention group, respectively. The intervention provided small but significant benefits compared to the control group for academic achievement (d=0.16; p=0.003), conduct problems (d=-0.28; p=0.003), cardiorespiratory fitness (d=0.36; p0.05).
Conclusions: A one-year school-based karate intervention was effective for the improvement of academic achievement, conduct problems, and physical fitness in primary school children, which supports the inclusion of karate during physical education lessons
LALINET: The First Latin American–Born Regional Atmospheric Observational Network
Sustained and coordinated efforts of lidar teams in Latin America at the beginning of the 21st century have built LALINET (Latin American Lidar NETwork), the only observational network in Latin America created by the agreement and commitment of Latin American scientists. They worked with limited funding but an abundance of enthusiasm and commitment toward their joint goal. Before LALINET, there were a few pioneering lidar stations operating in Latin America, described briefly here. Bi-annual Latin American Lidar Workshops, held from 2001 to the present, supported both the development of the regional lidar community and LALINET. At those meetings, lidar researchers from Latin America meet to conduct regular scientific and technical exchanges among themselves and with experts from the rest of the world. Regional and international scientific cooperation has played an important role for the development of both the individual teams and the network. The current LALINET status and activities are described, emphasizing the processes of standardization of the measurements, methodologies, calibration protocols, and retrieval algorithms. Failures and successes achieved in the buildup of LALINET are presented. In addition, the first LALINET joint measurement campaign and a set of aerosol extinction profile measurements obtained from the aerosol plume produced by the Calbuco volcano eruption on April 22, 2015, are described and discussed.Fil: Antuña Marrero, Juan Carlos. Centro Meteorológico de Camagüey; CubaFil: Landulfo, Eduardo. Instituto de Pesquisas Energéticas e Nucleares; BrasilFil: Estevan, René. Centro Meteorológico de Camagüey; CubaFil: Barja, Boris. Centro Meteorológico de Camagüey; Cuba. Universidade de Sao Paulo; BrasilFil: Robock, Alan. State University of New Jersey; Estados UnidosFil: Wolfram, Elian Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; ArgentinaFil: Ristori, Pablo Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; ArgentinaFil: Clemesha, Barclay. Upper Atmosphere Research Group; BrasilFil: Zaratti, Francesco. Universidad Mayor de San Andrés; BoliviaFil: Forno, Ricardo. Universidad Mayor de San Andrés; BoliviaFil: Armandillo, Errico. ESTEC; Países BajosFil: Bastidas, Álvaro E.. Universidad Nacional de Colombia. Sede Medellin; ColombiaFil: de Frutos Baraja, Ángel Máximo. Universidad de Valladolid; EspañaFil: Whiteman, David N.. National Aeronautics and Space Administration; Estados UnidosFil: Quel, Eduardo Jaime. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; ArgentinaFil: Barbosa, Henrique M. J.. Universidade de Sao Paulo; BrasilFil: Lopes, Fabio. Comissao Nacional de Energia Nuclear. Centro de Lasers e Aplicacoes. Instituto de Pesquisas Energeticas e Nucleares.; BrasilFil: Montilla-Rosero, Elena. Universidad de Concepción; Chile. Universidad Escuela de Administración, Finanzas e Instituto Tecnológico; ColombiaFil: Guerrero Rascado, Juan L.. Comissao Nacional de Energia Nuclear. Centro de Lasers e Aplicacoes. Instituto de Pesquisas Energeticas e Nucleares.; Brasil. Universidad de Granada; Españ
Measurement of the Depth of Maximum of Extensive Air Showers above 10^18 eV
We describe the measurement of the depth of maximum, Xmax, of the
longitudinal development of air showers induced by cosmic rays. Almost four
thousand events above 10^18 eV observed by the fluorescence detector of the
Pierre Auger Observatory in coincidence with at least one surface detector
station are selected for the analysis. The average shower maximum was found to
evolve with energy at a rate of (106 +35/-21) g/cm^2/decade below 10^(18.24 +/-
0.05) eV and (24 +/- 3) g/cm^2/decade above this energy. The measured
shower-to-shower fluctuations decrease from about 55 to 26 g/cm^2. The
interpretation of these results in terms of the cosmic ray mass composition is
briefly discussed.Comment: Accepted for publication by PR
The Pierre Auger Observatory III: Other Astrophysical Observations
Astrophysical observations of ultra-high-energy cosmic rays with the Pierre
Auger ObservatoryComment: Contributions to the 32nd International Cosmic Ray Conference,
Beijing, China, August 201
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