Search results for "Activity"

Frequency Based Detection and Monitoring of Small Scale Explosive Activity by Comparing Satellite and Ground Based Infrared Observations at Stromboli…

2014

Abstract Thermal activity is a common precursor to explosive volcanic activity. The ability to use these thermal precursors to monitor the volcano and obtain early warning about upcoming activity is beneficial for both human safety and infrastructure security. By using a very reliably active volcano, Stromboli Volcano in Italy, a method has been developed and tested to look at changes in the frequency of small scale explosive activity and how this activity changes prior to larger, ash producing explosive events. Thermal camera footage was used to designate parameters for typical explosions at Stromboli (size of spatter field, cooling rate, frequency of explosions) and this information was a…

Sensory performance of blind Mexican cave fish after destruction of the canal neuromasts.

1990

Diagenesis of speleothems and its effect on the accuracy of 230 Th/U-ages

2014

Abstract Speleothems can be precisely dated by U-series disequilibrium methods. One basic assumption of the 230Th/U-dating method is that the system remains closed and U and Th isotopes are neither lost nor added after deposition. For stalagmites, this requirement is usually fulfilled due to their protected environment in caves. However, undersaturated drip water may lead to diagenesis of speleothem CaCO3 and altered 230Th/U-ages. Here we present a detailed petrographic investigation using thin sections and 230Th/U-ages of a stalagmite from the Riesenberghohle, northern Germany, which grew during Marine Isotope Stages 5e, c and a. The occurrence of a mosaic fabric in large parts of the stal…

Radiative heat power at Stromboli volcano during 2000–2011: Twelve years of MODIS observations

2012

Abstract Twelve years of night-time MODIS (Moderate Resolution Imaging Spectroradiometer) observations, has been analysed to detect and quantify the radiative heat power emitted by Stromboli volcano (from March 2000 to September 2011). Using an accurate background subtraction of the MODIS signal at 4 μm, we were able to discriminate two main regimes of thermal radiation, related to different levels of volcanic activity. Effusive eruptions (occurred on December 28, 2002 and February 27, 2007) radiated at an average of ~ 186 MW with a frequency of alert detection of 50–95%. Conversely, during the typical strombolian activity, an average of ~ 9 MW is radiated, with a frequency of alert detecti…

Structural diversity and enzyme activity of volcanic soils at different stages of development and response to experimental disturbance

2008

We investigated the phospholipid fatty acid (PLFA) diversity and enzyme activities in soils from the volcano, Mt. Etna (Sicily). The soils were at sites which have been developing for different periods of time and have formed in volcanic lava of differing ages that have been supplemented with volcanic ejecta from subsequent eruptions. However, the plant communities indicated a marked successional difference between the sites and we have used this as a proxy for developmental stage. We have compared the structural and functional properties of the microbial communities in soils from the two sites and tested experimentally the hypothesis that the more diverse community was more resistant and r…

Activity overlap between mesocarnivores and prey in the Central Mongolian steppe

2021

Research on the ecology and behaviour of mesocarnivores and their prey is scant in Mongolia. We investigated activity patterns of a guild of mesocarnivores (red fox, Pallas's cat and beech marten) and their prey (Siberian marmot, Daurian pika, Brandt vole, Mongolian gerbil and Mongolian silver vole) using 21 camera traps (effort = 1155 camera days) in Central Mongolia from 25st of May to 20th August 2019. Activity patterns of mesocarnivores were cathemeral (i.e. no difference between diurnal, nocturnal and crepuscular detections, although activity peaked at sunrise). Among prey, the Siberian marmot and the Daurian pika were diurnal, whereas the Mongolian gerbil and the Mongolian silver vole…

Kompleksy metali przejściowych z zasadami Lewisa jako prekursory katalizatorów polimeryzacji olefin. Cz. I. Postęp w komputerowym modelowaniu procesu…

2001

A review with 35 references covering molecular modeling in coordination polymerization over homogeneous and heterogeneous Ziegler-Natta catalysts. The study includes supports, cocatalysts, Lewis bases and solvents. Recent progress in elucidating the mechanisrn of elementary polymerization steps is presented against the background of rapidly deveIoping computational methods and available computational power. Theoretical studies on polymerization mcchanisms and structure of active centers are described (egns. 1-4). Authors own calculations are used to compare [MtC14(THF)2] complex-based (Mt = Ti, Hf or Zr) heterogeneous catalysts. The geometrical characteristics of precursors is presented (Ta…

Microbiology meets geochemistry: geothermal flux shapes different microbial communities at the same exhalative area

2015

Volcanic/geothermal areas are sites of complex interactions between geosphere and biosphere. Pantelleria island (Southern Mediterranean Sea) hosts a high enthalpy geothermal system characterized by high CH4 and low H2S fluxes. Two sites, FAV1 and FAV2, located a few meters apart at the main exhalative area of the island (Favara Grande), recorded similar physical conditions (soil temperature 60°C, soil gas composition enriched in CH4, H2 and CO2). However, while high methanotrophic activity (59.2 nmol g-1 h-1) and high diversity of methanotrophs was detected at FAV2, FAV1 was not active and appeared deprived of methanotrophs (1). Our aim was to investigate the main factors influencing methan…

Chemical composition of the essential oil from Pulicaria vulgaris var. graeca (Sch.-Bip.) Fiori (Asteraceae) growing wild in Sicily and its antimicro…

2015

In this study the chemical composition of the essential oil from aerial parts of Pulicaria vulgaris var. graeca (Sch.-Bip.) Fiori collected in Sicily was evaluated by GC and GC–MS. The main components of P. vulgaris var. graeca oil were hexadecanoic acid (21.7%), β-caryophyllene (14.3%) and geranyl propionate (8.2%). The comparison with other studied oils of genus Pulicaria is discussed. Antibacterial activity against several bacteria, including some ones infesting historical art craft, was also determined.

Análisis de los motivos para la participación en actividades físicas de personas con y sin discapacidad

2006

Tradicionalmente, la actividad física adaptada ha sido utilizada para conseguir efectos terapéuticos y rehabilitadores en las personas con discapacidad. Actualmente, los educadores relacionados con la actividad física y deporte adaptado pretenden hacer ver a la sociedad en general que las personas con discapacidad pueden practicar actividades físicas y deportivas por las mismas motivaciones que las personas sin discapacidad. Para contribuir a este objetivo, y empleando como marco de referencia la teoría de las metas de logro, hemos analizado las motivaciones de una muestra de 80 personas con discapacidad funcional y otras 80 sin ningún tipo de discapacidad, todas ellas practicantes de activ…