A semiempirical error estimation technique for PWV derived from atmospheric radiosonde data

Water vapour is the main responsible for the atmospheric extinction in astronomical observations in different bands. One of the most common and accurate techniques to measure it are the radiosoundings. A method to estimate the error and the optimum number of sampled levels is proposed, considering the uncertainties and the leakage in sampling, based on data from Roque de los Muchachos Observ. and Guimar (Canary Is., Spain), Lindenberg (Germany) and Ny-Ålesund (Norway). The median error is 2.0  %

Estimación del error al medir vapor de agua precipitable con radiosondeos

Seminario impartido el 17 de octubre de 2016 en el Centro de Investigación Atmosférica de Izaña

The best skies for astronomy

Seminario impartido por Casiana Muñoz-Tuñón (IAC) el 15 de noviembre de 2016 en las Oficinas del CIAI en Santa Cruz de Tenerife

A semiempirical error estimation technique for PWV derived from atmospheric radiosonde data [Discussion paper]

Water vapour is the main responsible for the atmospheric extinction in astronomical observations in different bands. One of the most common and accurate techniques to measure it are the radiosoundings. A method to estimate the error and the optimum number of sampled levels is proposed, considering the uncertainties and the leakage in sampling, based on data from Roque de los Muchachos Observ. and Guimar (Canary Is., Spain), Lindenberg (Germany) and Ny-Ålesund (Norway). The median error is 2.0  %

Estudio del contenido de aerosoles para la caracterización de observatorios astronómicos

Seminario impartido por la Dra. Antonia M. Varela el 19 de enero de 2017 en las Oficinas del CIAI en Santa Cruz de Tenerife.La extinción atmosférica es el parámetro astronómico que determina la transparencia del cielo. La extinción se asocia a la absorción/dispersión de los fotones a su paso por la atmósfera de la Tierra. Las fuentes de degradación de la transparencia del cielo son principalmente las nubes y los aerosoles (partículas de polvo incluidas). Estudios recientes han explorado la utilidad de los datos de satélites y de archivos de diagnóstico climático (NCEP / NCAR) para la selección, caracterización y predicción de parámetros de interés astronómico. En particular, para determinar el contenido de aerosoles, cobertura de nubes, vapor de agua precipitable y otros parámetros relacionados con la turbulencia atmosférica y con las tendencias climáticas. Estos datos necesitan ser analizados críticamente e interpretados de acuerdo con la resolución espacial y temporal y con los canales espectroscópicos usados. Deben ser validados con datos obtenidos con instrumentos in situ. En esta charla revisaremos la contribución en este campo, centrándonos en la extinción atmosférica por aerosoles y en los vientos troposféricos para inferir la turbulencia atmosférica

Aplicación contrastada de técnicas de datación absoluta al yacimiento "Cueva de Tendal", isla de La Palma (Islas Canarias)

Con la intención de contrastar los resultados de diferentes técnicas geocronológicas, realizamos 7 determinaciones de termoluminiscencia (TL) y 4 de radiocarbono (14C) sobre diversos niveles estratigráficos del yacimiento del Tendal en la isla de La Palma. Los resultados obtenidos con ambas técnicas concuerdan aceptablemente y sólo encontramos ciertas diferencias en los niveles basales del yacimiento. La posible solución de esta discrepancia cabe buscarla, en futuras excavaciones, en la realización de una dosimetría de radiación gamma precisa para las edades TL, y en la búsqueda de sistemas cerrados, como por ejemplo otolitos de peces, para les edades 14C.With a view to comparing the results obtained using different geochronological techniques, we made 7 determinations by thermoluminiscence (TL) and 4 by radiocarbon (14C) over different stratigraphic levels of the Tendal site on the island of La Palma. The results obtained with both techniques are in acceptable agreement and certain discrepancies were only observed in the base layers of the site. The possible solution to these discrepancies may be sought during future excavations by performing a gamma radiation dosimetry for the TL ages, and by searching for closed systems such as, for example, fish otolites, for the 14C ages

The ESO’s Extremely Large Telescope Working Groups

Since 2005 ESO has been working with its community and industry to develop an extremely large optical/infrared telescope. ESO’s Extremely Large Telescope, or ELT for short, is a revolutionary ground-based telescope that will have a 39-metre main mirror and will be the largest visible and infrared light telescope in the world. To address specific topics that are needed for the science operations and calibrations of the telescope, thirteen specific working groups were created to coordinate the effort between ESO, the instrument consortia, and the wider community. We describe here the goals of these working groups as well as their achievements so far

International Nosocomial Infection Control Consortiu (INICC) report, data summary of 43 countries for 2007-2012. Device-associated module

We report the results of an International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2007-December 2012 in 503 intensive care units (ICUs) in Latin America, Asia, Africa, and Europe. During the 6-year study using the Centers for Disease Control and Prevention's (CDC) U.S. National Healthcare Safety Network (NHSN) definitions for device-associated health care–associated infection (DA-HAI), we collected prospective data from 605,310 patients hospitalized in the INICC's ICUs for an aggregate of 3,338,396 days. Although device utilization in the INICC's ICUs was similar to that reported from ICUs in the U.S. in the CDC's NHSN, rates of device-associated nosocomial infection were higher in the ICUs of the INICC hospitals: the pooled rate of central line–associated bloodstream infection in the INICC's ICUs, 4.9 per 1,000 central line days, is nearly 5-fold higher than the 0.9 per 1,000 central line days reported from comparable U.S. ICUs. The overall rate of ventilator-associated pneumonia was also higher (16.8 vs 1.1 per 1,000 ventilator days) as was the rate of catheter-associated urinary tract infection (5.5 vs 1.3 per 1,000 catheter days). Frequencies of resistance of Pseudomonas isolates to amikacin (42.8% vs 10%) and imipenem (42.4% vs 26.1%) and Klebsiella pneumoniae isolates to ceftazidime (71.2% vs 28.8%) and imipenem (19.6% vs 12.8%) were also higher in the INICC's ICUs compared with the ICUs of the CDC's NHSN