PACO: Python-Based Atmospheric COrrection.

The atmospheric correction of satellite images based on radiative transfer calculations is a prerequisite for many remote sensing applications. The software package ATCOR, developed at the German Aerospace Center (DLR), is a versatile atmospheric correction software, capable of processing data acquired by many different optical satellite sensors. Based on this well established algorithm, a new Python-based atmospheric correction software has been developed to generate L2A products of Sentinel-2, Landsat-8, and of new space-based hyperspectral sensors such as DESIS (DLR Earth Sensing Imaging Spectrometer) and EnMAP (Environmental Mapping and Analysis Program). This paper outlines the underlying algorithms of PACO, and presents the validation results by comparing L2A products generated from Sentinel-2 L1C images with in situ (AERONET and RadCalNet) data within VNIR-SWIR spectral wavelengths range.

Application of a Multivariant, Caucasian-Specific, Genotyped Donor Panel for Performance Validation of MDmulticard®, ID-System®, and Scangel® RhD/ABO Serotyping.

BACKGROUND: Validations of routinely used serological typing methods require intense performance evaluations typically including large numbers of samples before routine application. However, such evaluations could be improved considering information about the frequency of standard blood groups and their variants. METHODS: Using RHD and ABO population genetic data, a Caucasian-specific donor panel was compiled for a performance comparison of the three RhD and ABO serological typing methods MDmulticard (Medion Diagnostics), ID-System (DiaMed) and ScanGel (Bio-Rad). The final test panel included standard and variant RHD and ABO genotypes, e.g. RhD categories, partial and weak RhDs, RhD DELs, and ABO samples, mainly to interpret weak serological reactivity for blood group A specificity. All samples were from individuals recorded in our local DNA blood group typing database. RESULTS: For 'standard' blood groups, results of performance were clearly interpretable for all three serological methods compared. However, when focusing on specific variant phenotypes, pronounced differences in reaction strengths and specificities were observed between them. CONCLUSIONS: A genetically and ethnically predefined donor test panel consisting of 93 individual samples only, delivered highly significant results for serological performance comparisons. Such small panels offer impressive representative powers, higher as such based on statistical chances and large numbers only.

The new ID-heparin/PF4 antibody test for rapid detection of heparin-induced antibodies in comparison with functional and antigenic assays.

Heparin-induced thrombocytopenia (HIT) is an immune-mediated complication of heparin treatment. Several in vitro assays are available to detect the causative HIT antibodies: functional assays, usually requiring freshly prepared platelets and immunological tests based on the enzyme-linked immunosorbent assay (ELISA) principle. We compared a new, simple and rapid test based on the ID-microtyping particle agglutination system with 14C-serotonin release assay, heparin-induced platelet activation (HIPA) test and two ELISAs. Sera from 100 confirmed HIT patients, 20 serologically negative suspected HIT patients and 20 healthy blood donors were used. The specificity and sensitivity of the new test was similar to the functional assays. Compared with the ELISAs, specificity was better at the cost of reduced sensitivity. As in all other immunological tests, HIT antibodies against less typical antigens, such as interleukin (IL)-8 or neutrophil-activating peptide (NAP) 2 could not be detected. Thus, although the ID-Heparin/PF4 antibody test seems to be a quick, reliable and robust test to determine the presence of HIT antibodies, it should still be combined with a functional assay if possible. Evaluation of the test in a prospective setting as well as interlaboratory variation should be assessed as a next step.

Serodiagnosis of Trypanosoma cruzi infection using the new particle gel immunoassay - ID-PaGIA Chagas

The ID-Chagas test is a particle gel immunoassay (PaGIA). Red coloured particles are sensitised with three different synthtic peptides representing antigen sequences of Trypanosoma cruzi: Ag2, TcD and TcE. When these particles are mixed with serum containing specific antibodies, they agglutinate. The reaction mixture is centrifuged through a gel filtration matrix allowing free agglutinated particles to remain trapped on the top or distributed within the gel. The result can be read visually. In order to investigate the ability of the ID-PaGIA to discriminate negative and positive sera, 111 negative and 119 positive, collected in four different Brazilian institutions, were tested by each of the participants. All sera were previously classified as positive or negative according to results obtained with three conventional tests (indirect immunofluorescence, indirect hemaglutination, and enzyme linked immunosorbent assay). Sensitivity rates of ID-PaGIA varied from 95.7 per cent to 97.4 per cent with mean sensitivity of 96.8 per cent and specificity rates varied from 93.8 to 98.8 per cent with mean specificity of 94.6 per cent. The overall Kappa test was 0.94. The assay presents as advantages the simplicity of operation and the reaction time of 20 min. In this study, ID-PaGIA showed to be highly sensitive and specific.