3 research outputs found
Advancing Field-Based GNSS Surveying for Validation of Remotely Sensed Water Surface Elevation Products
To advance monitoring of surface water resources, new remote sensing technologies including the forthcoming Surface Water and Ocean Topography (SWOT) satellite (expected launch 2022) and its experimental airborne prototype AirSWOT are being developed to repeatedly map water surface elevation (WSE) and slope (WSS) of the worldâs rivers, lakes, and reservoirs. However, the vertical accuracies of these novel technologies are largely unverified; thus, standard and repeatable field procedures to validate remotely sensed WSE and WSS are needed. To that end, we designed, engineered, and operationalized a Water Surface Profiler (WaSP) system that efficiently and accurately surveys WSE and WSS in a variety of surface water environments using Global Navigation Satellite Systems (GNSS) time-averaged measurements with Precise Point Positioning corrections. Here, we present WaSP construction, deployment, and a data processing workflow. We demonstrate WaSP data collections from repeat field deployments in the North Saskatchewan River and three prairie pothole lakes near Saskatoon, Saskatchewan, Canada. We find that WaSP reproducibly measures WSE and WSS with vertical accuracies similar to standard field survey methods [WSE root mean squared difference (RMSD) âŒ8 cm, WSS RMSD âŒ1.3 cm/km] and that repeat WaSP deployments accurately quantify water level changes (RMSD âŒ3 cm). Collectively, these results suggest that WaSP is an easily deployed, self-contained system with sufficient accuracy for validating the decimeter-level expected accuracies of SWOT and AirSWOT. We conclude by discussing the utility of WaSP for validating airborne and spaceborne WSE mappings, present 63 WaSP in situ lake WSE measurements collected in support of NASAâs Arctic-Boreal and Vulnerability Experiment, highlight routine deployment in support of the Lake Observation by Citizen Scientists and Satellites project, and explore WaSP utility for validating a novel GNSS interferometric reflectometry LArge Wave Warning System
Hazard Evaluation of Inorganics, Singly and in Mixtures, to Flannelmouth SuckerCatostomus latipinnisin the San Juan River, New Mexico
Isolamento e caracterização do vĂrus da influenza pandĂȘmico H1N1 em suĂnos no Brasil
A infecção causada pelo vĂrus Influenza A (IAV) Ă© endĂȘmica em suĂnos no mundo inteiro. O surgimento da pandemia de influenza humana pelo vĂrus A/H1N1 (pH1N1) em 2009 levantou dĂșvidas sobre a ocorrĂȘncia deste vĂrus em suĂnos no Brasil. Durante o desenvolvimento de um projeto de pesquisa do vĂrus de influenza suĂna em 2009-2010, na Embrapa SuĂnos e Aves (CNPSA), foi detectado em um rebanho de suĂnos em Santa Catarina, Brasil, um surto de influenza altamente transmissĂvel causado pelo subtipo viral H1N1. Este vĂrus causou uma doença leve em suĂnos em crescimento e em fĂȘmeas adultas, sem mortalidade. Tres leitĂ”es clinicamente afetados foram eutanasiados. As lesĂ”es macroscĂłpicas incluiam consolidação leve a moderada das ĂĄreas cranioventrais do pulmĂŁo. Microscopicamente, as lesĂ”es foram caracterizadas por bronquiolite necrosante obliterativa e pneumonia broncointersticial. A imunohistoquĂmica, utilizando um anticorpo monoclonal contra a nucleoproteĂna do vĂrus influenza A, revelou marcação positiva no nĂșcleo das cĂ©lulas epiteliais bronquiolares. O tecido pulmonar de trĂȘs leitĂ”es e os suabes nasais de cinco fĂȘmeas e quatro leitĂ”es foram positivos para influenza A pela RT-PCR. O vĂrus influenza foi isolado de um pulmĂŁo, mais tarde sendo confirmado pelo teste de hemaglutinação (tĂtulo HA 1:128) e por RT-PCR. A anĂĄlise das seqĂŒĂȘncias de nucleotĂdeos dos genes da hemaglutinina (HA) e proteĂna da matriz (M) revelou que o vĂrus isolado foi consistente com o vĂrus pandĂȘmico A/H1N1/2009 que circulou em humanos no mesmo perĂodo. Este Ă© o primeiro relato de um surto de influenza causado pelo vĂrus pandĂȘmico A/H1N1 em suĂnos no Brasil