51 research outputs found

    Hazardous gas emissions from the flanks of the quiescent Colli Albani volcano (Rome, Italy)

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    Gas hazard was evaluated in the three most important cold gas emission zones on the flanks of the quiescent Colli Albani volcano. These zones are located above structural highs of the buried carbonate basement which represents the main regional aquifer and the main reservoir for gas rising from depth. All extensional faults affecting the limestone reservoir represent leaking pathways along which gas rises to the surface and locally accumulates in shallow permeable horizons forming pressurized pockets that may produce gas blowout when reached by wells. The gas, mainly composed by CO2 (>90 vol.%), contains appreciable quantities of H2S (0.35-6 vol.%), and both represent a potentially high local hazard. Both gases are denser than air and accumulate near ground where they may reach hazardous concentrations, and actually lethal accidents frequently occur to animals watering at local ponds. In order to evaluate the rate of degassing and the related hazard, CO2 and H2S diffuse soil flux surveys have been repeatedly carried out by accumulation chamber. The viscous gas flux of some important discrete emissions has been also evaluated and the CO2 and H2S air concentration measured by portable devises and by Tunable Diode Laser profiles. The minimum potential lethal concentration of the two gases (250 ppm for H2S and 8 vol.% for CO2) is 320 times higher for CO2, whereas the CO2/H2S concentration ratio in the emitted natural gas is significantly lower (15-159). This explains why H2S reaches hazardous, even lethal, concentrations more frequently than CO2. A relevant hazard exists for both gases in the depressed zones (channels, excavations) particularly in the non-windy early hours of the day

    Magma emission rates fromshallow submarine eruptions using airborne thermal imaging

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    The effusion rate is the most important parameter to gatherwhen a volcanic eruption occurs, because it controls the way inwhich a lava body grows, extends and expands, influencing its dimensional properties. Calculation of lava flow volume from thermal images collected by helicopter surveys has been largely used during the last decade for monitoring subaerial effusive eruptions. However, due to the depths where volcanic activity occurs, monitoring submarine volcanic eruptions is a very difficult task. The 2011–2012 submarine volcanic eruption at El Hierro, Canary Islands, has provided a unique and excellent opportunity to monitor eruptive processes occurring on the seabed. The use of a hand-held thermal camera during daily helicopter flights allowed us to estimate for the first time the daily and total erupted magma volumes from a submarine eruption. The volume of magma emitted during this eruption has been estimated at 300 Mm3, giving an average effusion rate of ~25 m3 s−1. Thermal imagery by helicopter proved to be a fast, inexpensive, safe and reliable technique of monitoring volcanic eruptions when they occur on the shallow seabed.This research was financially supported by the projects MAKAVOL (MAC/3/C161) from the European Union MAC 2007–2013 Transnational Cooperation Program as well as from the Cabildo Insular de Tenerife. We are also grateful to the staff of El Hierro airport (AENA) for providing logistical support.Published219-2255V. Sorveglianza vulcanica ed emergenzeJCR Journalrestricte

    Estudio sobre la integración en aula específica, de un IES, de alumnado diagnosticado como negativista desafiante y su posible inclusión en aula ordinaria

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    It is known that, nowadays, with the arrival of the inclusive school, in our classrooms we find a greater functional diversity in the students than in the past, diversity that is not always known and accepted within normality. The present investigation, based on the real experience, has as objective the integration in an IES of specific classroom of students affected by serious behavior disorders, such as the defiant negativist disorder, for its later inclusion in the ordinary classroom, in principle, under supervision. The sample consists of 5 subjects whose ages range between 13 and 15 years, who, due to serious alterations in their behavior, can not have full-time schooling in the ordinary classroom. Three of these students are enrolled in 1st of Compulsory Secondary Education (ESO) and 2 of them in 2nd. The serious behavioral problems led to the application of a behavior modification program and a cognitive restructuring and a self-control training.Es sabido que, en la actualidad, con la llegada de la escuela inclusiva, en nuestras aulas nosencontramos con una mayor diversidad funcional en el alumnado que en tiempos pasados, diversidad que no siempre es conocida y aceptada dentro de la normalidad. La presente investigación, basada en la experiencia real, tiene como objetivo la integración en un IES de un aula específica de alumnado afectado de trastornos graves de conducta, como es el trastorno negativista desafiante, para su posterior inclusión en el aula ordinaria, en principio, bajo supervisión. La muestra consta de 5 sujetos cuyas edades oscilan entre los 13 y 15 años, que por presentar graves alteraciones en su conducta no pueden tener una escolarización a tiempo completo en el aula ordinaria. Tres de estos alumnos, estan matriculados en 1º de la Educación Secundaria Obligatoria (ESO) y 2 de ellos en 2º. Los graves problemas de conducta llevaron a la aplicación de un programa de modificación de conducta cognitivo conductual, a una reestructuración cognitiva y a un entrenamiento en autocontrol

    The peasant women and representations of Chagas disease

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    Mujer campesina y representaciones sobre la enfermedad de Chagas

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