Search for extended γ-ray emission around AGN with MAGIC telescopes

TeV photons coming from a distant extragalactic source are not able to propagate over large distances because they interact with the extragalactic background light photons producing pairs e+e−. These pairs, in turn, interact with the cosmic microwave background via inverse-compton producing a secondary γ-ray emission at lower energies. Extragalactic magnetic fields alter the trajectories of the electron pairs hence the secondary emission can be extended around the TeV sources. This process can be used to constrain the magnetic fields in the inter-galactic medium. We present the study of the emission profile of the blazar Markarian 421 yielding upper limit on the halo flux of the order of 1.5% Crab units in the energy range 300–1300 GeV

Detection of Walls, Floors, and Ceilings in Point Cloud Data

This is the author accepted manuscript. The final version is available from the American Society of Civil Engineers via http://dx.doi.org/10.1061/9780784479827.229The successful implementation of Building Information Models (BIMs) for facility management, maintenance and operation is highly dependent on the ability to generate such models for existing assets. Generating such BIMs typically requires laser scanning to acquire point clouds and significant post-processing to register the clouds, replace the points with BIM objects, assign semantic relationships and add any additional properties, such as materials. Several research efforts have attempted to reduce the post-processing manual effort by classifying the structural elements and clutter in isolated rooms. They have not however examined the complexity of a whole building. In this paper, we propose a robust framework that can automatically process the point cloud of an entire building, possibly with multiple floors, and classify the points belonging to floors, walls and ceilings.. We first extract the planar surfaces by segmenting the point cloud, and then we use contextual reasoning, such as height, orientation, relation to other objects, and local statistics like point density in order to classify them into objects. Experiments were conducted on a registered point cloud of an office building. The results indicated that almost all of the walls and floors/ceilings were correctly clustered in the point cloud.The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreements n° 247586 ("BIMAutoGen") and n° 334241 ("INFRASTRUCTUREMODELS")

Gas chromatographic-sulfur chemiluminescent detector procedures for the simultaneous determination of free forms of volatile sulfur compounds including sulfur dioxide and for the determination of their metal-complexed forms

Three different procedures for the quantitative assessment of free and metal complexed volatile sulfur compounds (VSCs) and for the determination of truly free SO 2 have been developed, taking advantage of a GC-sulfur chemiluminescent detector system (GC-SCD) with cryotrapping. The inertness of the inlet systems, together with the column used (SPB-1 sulfur) makes it possible to obtain a non-saturated perfectly Gaussian peak for SO 2 , well resolved from H 2 S. In the main procedure, the injection of 1 mL of the headspace of a sample prepared in complete anoxia and equilibrated at 30 °C makes it possible to get highly sensitive signals for all VSCs and free SO 2 . Detection limits are 3, 35 and 60 ng/L for H 2 S, MeSH and EtSH, 13 µg/L for truly free SO 2 (at pH = 3.4, or 0.46 µg/L for molecular SO 2 ), and better than 1 µg/L for other relevant sulfur volatiles. Method precision is also satisfactory and linearity covers the whole range of occurrence of these compounds. A second procedure, not making use of the cryotrapping unit, gives also satisfactory results, although with higher detection limits (0.03, 0.25 and 0.37 µg/L for free H 2 S, MeSH and EtSH, respectively). For the analysis of free plus metal-complexed forms, it has been demonstrated that the headspace injection of the vapors on a 1:10 brine dilution of the sample heated at 70 °C for 25 min, gives good estimates of the free + metal-complexed forms of H 2 S and wine mercaptans

"I am Maya, not Guatemalan, nor Hispanic"—the Belongingness of Mayas in Southern Florida

Dieser Artikel untersucht die persönlichen Bedeutungen und die öffentlichen Darstellungen von Zuhause, Ethnizität und Zugehörigkeitsgefühl von Maya-guatemaltekischen Immigrant/innen in Florida. Die Ergebnisse basieren auf der Analyse von sieben Biografien von Maya-Einwanderer/innen der ersten und zweiten Generation. Die narrative Analyse zeigt, dass die Immigrant/innen aktiv gegen eine öffentliche Miss-Kategorisierung als Teil der Hispanischen Gemeinschaft Widerstand leisten, indem sie ihre indigene Herkunft hervorheben. In diesem Sinne bietet unserer Studie eine neue Art der Forschung im Hinblick auf Maya-Einwanderer/innen und ihre "Positionierung" und "Selbst-Lokalsierung" als indigene Völker, welche Zuflucht in den Vereinigten Staaten suchen. Es handelt sich um Lebensgeschichten von Mayas – die meisten von ihnen überlebten als Kinder – welche mit ihren Familien vor dem Völkermord in Guatemala geflohen sind und in ihrem Leben in den Vereinigten Staaten diskriminiert werden. Das Einzigartige an unserer Studie ist die Betonung der Biografien, welche bestimmte Aspekte von Ethnizität und Indigenität und die schwierigen Prozesse transnationaler Migration von Mayas, die nun in Florida leben, hervorheben. URN: urn:nbn:de:0114-fqs0903106Este artículo examina los significados personales y expresiones públicas sobre lo que es la casa (lugar de origen), etnicidad y sentimiento de pertenencia entre los inmigrantes mayas de Guatemala a Florida, Estados Unidos. Se presenta el análisis de siete entrevistas biográficas realizado con inmigrantes mayas de primera y segunda generación. El análisis narrativo muestra que los inmigrantes apuntan su origen indígena como forma de resistencia en contra de una categorización falsa como parte de la comunidad hispana. En este sentido, nuestro estudio ofrece una nueva forma de investigación con respecto a los inmigrantes mayas y a la "colocación" y "auto-localización" de los pueblos indígenas que buscan refugio en los Estados Unidos. Se trata de historias de vida de mayas, la mayoría de los cuales sobrevivieron como niños, que huyeron con sus familias del genocidio en Guatemala y que han sido discriminados en los Estados Unidos. Lo particular de nuestro estudio es el énfasis sobre las biografías que enfatizan aspectos específicos de etnicidad y indigenidad y sobre las dificultades de los procesos de migración trasnacional de mayas que ahora pertenecen a Florida. URN: urn:nbn:de:0114-fqs0903106This article explores the personal meanings and public expressions of home, ethnicity and belonging among Maya/Guatemalan immigrants living in South Florida, specifically from the viewpoints of seven biographies of first and second-generation Maya immigrants. Our examination of their narratives suggests why these immigrants actively resist a public mis-categorization of being part of the Hispanic community by emphasizing their indigenous heritage. As such, this study provides a new type of research regarding Maya immigrants and their "positioning" or their "self-localization" as indigenous peoples seeking refuge in the United States. These are narratives of Maya lives, most of them child survivors, who fled the genocide in Guatemala with their families and who have faced discrimination while living in the United States. What is unique about our study is its emphasis upon biography for portraying particular facets of ethnicity and indigeneity and the difficult processes of transnational migration faced by Maya peoples now living in Florida. URN: urn:nbn:de:0114-fqs090310

The effects of copper fining on the wine content in sulfur off-odors and on their evolution during accelerated anoxic storage

Three different red wines with reductive character have been treated with two different doses of copper sulfate (0.06 and 0.5 mg/L) and with a commercial copper-containing product at the recommended dose (0.6 mg/L). Wines were in contact with copper one week, centrifuged and stored at 50 °C in strict anoxia for 2 weeks (up to 7 in one case). Brine-releasable (BR-) and free fractions of Volatile Sulfur Compounds were determined throughout the process. Relevant increases of BR-H2S suggest that those wines contained other H2S precursors non-detectable by the brine dilution method. Copper treatments had two major effects: 1) immediate decrease the levels of free H2S and methanethiol (MeSH); 2) slow the rate at which free H2S (not MeSH) increases during anoxic storage. After 7 weeks of anoxia levels of free H2S and MeSH were high and similar regardless of the copper treatment. Higher copper doses could induce the accumulation of BR-H2S