28 research outputs found

    Evidence of low levels of genetic diversity for the Phytophthora austrocedrae population in Patagonia, Argentina

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    Phytophthora austrocedrae is a recently discovered pathogen that causes severe mortality of Austrocedrus chilensis in Patagonia. The high level of susceptibility of the host tree, together with the distribution pattern of the pathogen, have led to the hypothesis that P. austrocedrae was introduced into Argentina. The aim of this study was to assess the population structure of P. austrocedrae isolates from Argentina in order to gain an understanding of the origin and spread of the pathogen. Genetic diversity was determined based on amplified fragment length polymorphisms (AFLPs). In total, 48 isolates of P. austrocedrae were obtained from infected A. chilensis trees, representing the geographical range of the host. Four primer combinations were used for the AFLP analysis. Of the 332 scored bands, 12% were polymorphic. Gene diversity (h) ranged from 0 01 to 0 03; the Shannon index (I) ranged from 0 01 to 0 04. A high degree of genetic similarity was observed among the isolates (pairwise S values = 0 958–1; 0 993 0 009, mean SD). A frequency histogram showed that most of the isolate pairs were identical. Principal coordinate analysis using three-dimensional plots did not group any of the isolates based on their geographical origin. The low genetic diversity (within and between sites) and absence of population structure linked to geographic origin, together with the aggressiveness of the pathogen and the disease progression pattern, suggest that P. austrocedrae might have been introduced into Argentina.The Tree Protection Co-operative Programme (TPCP) and the NRF/DST Centre of Excellence in Tree Health Biotechnology (CTHB), South Africa.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-30592015-02-27hb201

    Fixed and drifting buoys around the national Spanish waters

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    Joint Technical Commission for Oceanography and Marine Meteorology (JCOMM) Marine Technical Conference, The Technical Conference (TECO) Toward an Integrated Met-ocean Monitoring, Forecasting and Services System, 25-29 October 2017, Geneva, SwitzerlandImproving the knowledge of the ocean and seas surrounding the Iberian Peninsula and Balearic and Canary islands is an objective of the Spanish oceanography. For that purpose, a number of fixed and drifting floats have been established in the last 25 years. Data buoys measure sea surface temperature and salinity, ocean current velocity, air temperature, humidity, wave characteristic and wind velocity across seas and ocean. The objective is increase the quantity, quality, coverage and timeliness of atmospheric and oceanographic data. These observations are used immediately to improve forecast and therefore increase marine safety. The main group of fixed buoys is formed by the Puertos del Estado deep and shallow buoy networks, but a series of well instrumented new platforms has been established in later times. The RAIA Project (Xunta de Galicia), PLOCAN, SOCIB, IEO, Euskalmet-AZTI, ICM and UTM (CSIC) and University and Polytechnic of Barcelona have completed the Observing System. Most of the buoys are transmitting data by GTS for using in atmospheric and ocean prediction models. Multidisciplinary sensors as Dissolved Oxygen, Fluorescence Chlorophyll or pCO2 has been mounted in the buoys and calibration/validation procedures has been developed for improve data quality. Antifouling systems recently developed have also been included and quality of the optical sensors measurements has improved. Drifting floats has increase its number and importance, from Argo floats to traditional deriving ones improving the Spanish contribution to IOC and WWO and JCOMM. Spain is member of EuroArgo ERIC. SOCIB and IEO are the main contributors. Also multidisciplinary work has been done associated to Argo buoys. BGQ ARGO incorporate O2 sensor. ICM, SMOS Barcelona Expert Center, and SOCIB are the main contributors to the drifting buoys group. Main objectives are improving Technological development as well as data management. Tropical and Southern Atlantic Ocean are the main studying areasPeer Reviewe

    All-particle cosmic ray energy spectrum measured with 26 IceTop stations

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    We report on a measurement of the cosmic ray energy spectrum with the IceTop air shower array, the surface component of the IceCube Neutrino Observatory at the South Pole. The data used in this analysis were taken between June and October, 2007, with 26 surface stations operational at that time, corresponding to about one third of the final array. The fiducial area used in this analysis was 0.122 km^2. The analysis investigated the energy spectrum from 1 to 100 PeV measured for three different zenith angle ranges between 0{\deg} and 46{\deg}. Because of the isotropy of cosmic rays in this energy range the spectra from all zenith angle intervals have to agree. The cosmic-ray energy spectrum was determined under different assumptions on the primary mass composition. Good agreement of spectra in the three zenith angle ranges was found for the assumption of pure proton and a simple two-component model. For zenith angles {\theta} < 30{\deg}, where the mass dependence is smallest, the knee in the cosmic ray energy spectrum was observed between 3.5 and 4.32 PeV, depending on composition assumption. Spectral indices above the knee range from -3.08 to -3.11 depending on primary mass composition assumption. Moreover, an indication of a flattening of the spectrum above 22 PeV were observed.Comment: 38 pages, 17 figure

    An improved method for measuring muon energy using the truncated mean of dE/dx

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    The measurement of muon energy is critical for many analyses in large Cherenkov detectors, particularly those that involve separating extraterrestrial neutrinos from the atmospheric neutrino background. Muon energy has traditionally been determined by measuring the specific energy loss (dE/dx) along the muon's path and relating the dE/dx to the muon energy. Because high-energy muons (E_mu > 1 TeV) lose energy randomly, the spread in dE/dx values is quite large, leading to a typical energy resolution of 0.29 in log10(E_mu) for a muon observed over a 1 km path length in the IceCube detector. In this paper, we present an improved method that uses a truncated mean and other techniques to determine the muon energy. The muon track is divided into separate segments with individual dE/dx values. The elimination of segments with the highest dE/dx results in an overall dE/dx that is more closely correlated to the muon energy. This method results in an energy resolution of 0.22 in log10(E_mu), which gives a 26% improvement. This technique is applicable to any large water or ice detector and potentially to large scintillator or liquid argon detectors.Comment: 12 pages, 16 figure

    Fixed and Drifting Buoys around the National Spanish Waters

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    Improving the knowledge of the seas surrounding the Iberian Peninsula, Balearic and Canary islands is one of the objectives for the Spanish oceanographic community. For that purpose, a number of fixed and drifting buoys have been deployed in the last 25 years. Parameters measured included sea surface temperature and salinity, ocean current velocity, air temperature, humidity, wave characteristic and wind velocity. The national aim is to increase the quantity, quality, coverage and timeliness of atmospheric and oceanographic data. These observations are used immediately to improve forecast and therefore increase marine safety

    Autoantibodies against type I IFNs in patients with life-threatening COVID-19

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    Interindividual clinical variability in the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is vast. We report that at least 101 of 987 patients with life-threatening coronavirus disease 2019 (COVID-19) pneumonia had neutralizing immunoglobulin G (IgG) autoantibodies (auto-Abs) against interferon-w (IFN-w) (13 patients), against the 13 types of IFN-a (36), or against both (52) at the onset of critical disease; a few also had auto-Abs against the other three type I IFNs. The auto-Abs neutralize the ability of the corresponding type I IFNs to block SARS-CoV-2 infection in vitro. These auto-Abs were not found in 663 individuals with asymptomatic or mild SARS-CoV-2 infection and were present in only 4 of 1227 healthy individuals. Patients with auto-Abs were aged 25 to 87 years and 95 of the 101 were men. A B cell autoimmune phenocopy of inborn errors of type I IFN immunity accounts for life-threatening COVID-19 pneumonia in at least 2.6% of women and 12.5% of men

    International nosocomial infection control consortium (INICC) report, data summary of 36 countries, for 2004-2009

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    The results of a surveillance study conducted by the International Nosocomial Infection Control Consortium (INICC) from January 2004 through December 2009 in 422 intensive care units (ICUs) of 36 countries in Latin America, Asia, Africa, and Europe are reported. During the 6-year study period, using Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN; formerly the National Nosocomial Infection Surveillance system [NNIS]) definitions for device-associated health care-associated infections, we gathered prospective data from 313,008 patients hospitalized in the consortium's ICUs for an aggregate of 2,194,897 ICU bed-days. Despite the fact that the use of devices in the developing countries' ICUs was remarkably similar to that reported in US ICUs in the CDC's NHSN, rates of device-associated nosocomial infection were significantly higher in the ICUs of the INICC hospitals; the pooled rate of central line-associated bloodstream infection in the INICC ICUs of 6.8 per 1,000 central line-days was more than 3-fold higher than the 2.0 per 1,000 central line-days reported in comparable US ICUs. The overall rate of ventilator-associated pneumonia also was far higher (15.8 vs 3.3 per 1,000 ventilator-days), as was the rate of catheter-associated urinary tract infection (6.3 vs. 3.3 per 1,000 catheter-days). Notably, the frequencies of resistance of Pseudomonas aeruginosa isolates to imipenem (47.2% vs 23.0%), Klebsiella pneumoniae isolates to ceftazidime (76.3% vs 27.1%), Escherichia coli isolates to ceftazidime (66.7% vs 8.1%), Staphylococcus aureus isolates to methicillin (84.4% vs 56.8%), were also higher in the consortium's ICUs, and the crude unadjusted excess mortalities of device-related infections ranged from 7.3% (for catheter-associated urinary tract infection) to 15.2% (for ventilator-associated pneumonia). Copyright © 2012 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved

    Influences de la sylviculture sur le risque de dégâts biotiques et abiotiques dans les peuplements forestiers

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