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The Sentinel-2A and Sentinel-2B constellation is an Earth observation optical mission developed and operated by the European Space Agency in the frame of the Copernicus program of the European Commission. The novel observation capacity offered by the multispectral instruments (MSI) on-board Sentinel-2 mission provides a massive resource for the Earth observation community. The accurate radiometric calibration is a critical element of the success of the mission; therefore, in-orbit calibration and validation activities are conducted within the Sentinel-2 Mission Performance Centre. The database of the imaging multispectral instrument and tool for radiometric intercomparison and the ground measurements of the radiometric calibration network (RadCalNet) are used to perform the vicarious validation of the radiometry of the Level-1 products delivered to the users. The aims of this validation are to assess the quality of the data product, to monitor the evolution of the radiometry of both instruments, and to ensure that the products meet the mission requirement accuracy. This article outlines the vicarious methods—Rayleigh scattering, desert pseudoinvariant calibration sites, sensor-to-sensor intercalibration, and the ground reflectance-based approach—that are used for the Sentinel-2 radiometry validation. The validation results indicate good performance and stability of both sensors MSI-A and MSI-B and consistency up to ∼1% (∼2% for red-edge bands) between them. The results of the intercomparison with the in situ measurements from RadCalNet illustrate the relevance of such dataset for the vicarious validation activity.

With more than 4 TB of data acquired every day, the Sentinel 2 mission poses new challenges for quality control (QC). To support the QC operations of Sentinel 2, a dedicated tool has been developed for improved efficiency and traceability of analyses. This tool aims at helping visual inspection by human operators through automatic product retrieval, generation of quicklook images and production of quality indicators. The article describes the product sampling strategy used to select products suitable for quality control checks. Then we present the methodology used to generate quicklooks, compute relative and multi-spectral co-registration performance. The final step is the production of end-to-end service performance indicators. Lessons learnt from the first year of operation of this tool are presented regarding detected product anomalies and measured performance trends.

International audience; As part of the Copernicus programme of the European Commission (EC), the European Space Agency (ESA) operates the Sentinel-2 mission that acquires high spatial resolution optical imagery. The consistency of the image time series is ensured by some specific performance requirements such as multi-temporal spatial registration and radiometric stability, routinely monitored by the Sentinel-2 Mission Performance Centre (S2MPC). The products also provide a rich set of metadata and auxiliary data to support high-level processing activities. This presentation provides a description of the main level-1 products calibration and validation activities, performed by the S2MPC including several Expert Support Laboratories (ESL). Measured performances and analysed results show the good quality of the mission products both in terms of radiometry and geometry. The current performances for Sentinel-2A and Sentinel-2B are compared to mission product quality requirements.

Sentinel-2 is an Earth Observation optical mission developed and operated by the European Space Agency (ESA) in the frame of the Copernicus program of the European Commission. The mission consists on a MultiSpectral Instruments (MSI) on board a constellation of two satellites flying on the same orbit but phased at 180°: Sentinel-2A launched in June 2015 and Sentinel-2B launched in March 2017. It covers the Earth's land surfaces and inland and coastal waters every five days at the equator under the same viewing conditions with high spatial resolution and wide field of view. Accurate radiometric calibration is key to the success of the mission; therefore, in-orbit calibration and validation activities are conducted within the Sentinel-2 Mission Performance Centre (MPC), including a consortium of Expert Support Laboratories (ESL). The Database of Imaging Multispectral Instrument and Tool for Radiometric Intercomparison (DIMITRI) is used to perform the vicarious validation of Level-l products delivered to users. The aims of this validation are 1) to assess the quality of the data product at Level-1, 2) to monitor the evolution of the radiometry of both instruments and 3) to ensure that the products meet the mission requirement accuracy. Three vicarious methods are used, such as Rayleigh scattering, Desert Pseudo- Invariant Calibration Sites (PICS) and Sensor-to-Sensor intercalibration methods. Although the results indicate good stability and performance of both sensors MSI-A/B, a slight discrepancy between them of ~1 % over desert sites could be observed. Slight decrease of band B8A (865 nm) signal over Algeria-3 site has been detected since April 2017. This effect seems to be related to the impact of human and industry activities near the area. Radiometric performances and image quality of Sentinel-2 MSI-A/B level-1C products appear stable and meet the mission requirements.

The Landsat program is a joint United States Geological Survey (USGS) and National Aeronautics and Space Administration (NASA) enterprise for Earth Observation (EO), that represents the world’s longest running system of satellites for moderate-resolution optical remote sensing. The European Space Agency (ESA) has acquired Landsat data over Europe through the ESA ground stations over the last 40 years, in co-operation with USGS and NASA. A new ESA Landsat Multi-Spectral Scanner (MSS), Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) processor has been developed. This enhanced processor aligns the historical Landsat products to the highest quality standards that can be achieved with the current knowledge of the instruments. The updated processor is mainly based on the USGS algorithm; however the ESA processor has some different features that are detailed in this paper. Using this upgraded processor, ESA is currently performing for the first time a bulk-processing of its entire Landsat series MSS/TM/ETM+ historical archive to make all products available to users. Current achievements include the processing and online distribution of approximately 290 000 new Landsat 5 TM high-quality products acquired at the Kiruna ground station between 1983 and 2011. The Landsat 5 TM bulk-processed products are made available for direct download after registration at: https://earth.esa.int/web/guest/pi-community/apply for-data/fast-registration. The remainder of the ESA’s Landsat data, dating back more than 40 years, will gradually become available for all users during the course of 2014. The ESA Landsat processor algorithm enhancement, together with the results of the ESA archive bulk-processing, and an overview on the data quality on a subset of the Landsat 5 TM data are herein presented.

The delivery of holistic care should incorporate patient empowerment through the promotion of health and self-help measures, including pain relief. In this article, the author, a newly qualified independent prescriber, explains why she believes that encouraging patients to buy over-the-counter medication is morally acceptable and based on the principles of beneficence and non-malevolence. She also reflects on her prescribing decisions in the context of ethics, health economics and personal perspective for four patients with similar injuries. The author works in Wales, where prescriptions are free to residents.

Although tests of young children's understanding of mind have had a remarkable impact upon developmental and clinical psychological research over the past 20 years, very little is known about their reliability. Indeed, the only existing study of test-retest reliability suggests unacceptably poor results for first-order false-belief tasks (Mayes, Klin, Tercyak, Cicchetti, & Cohen, 1996), although this may in part reflect the nonstandard (video-based) procedures adopted by these authors. The present study had four major aims. The first was to re-examine the reliability of false-belief tasks, using more standard (puppet and storybook) procedures. The second was to assess whether the test-retest reliability of false-belief task performance is equivalent for children of contrasting ability levels. The third aim was to explore whether adopting an aggregate approach improves the reliability with which children's early mental-state awareness can be measured. The fourth aim was to examine for the first time the test-retest reliability of children's performances on more advanced theory-of-mind tasks. Our results suggest that most standard and advanced false-belief tasks do in fact show good test-retest reliability and internal consistency, with very strong test-retest correlations between aggregate scores for children of all levels of ability.

Background: This study focuses on a novel observational paradigm (SNAP) involving a rigged competitive card game (Murray, Woolgar, Cooper, & Hipwell, 2001) designed to expose children to the threat of losing. Recent work suggests that this paradigm is useful for assessing disruptive behaviour in young children (Hughes, Cutting, & Dunn, 2001). Method: We report on a large study (involving 800 five-year-olds) that compares observational ratings of disruptive behaviour on the SNAP game with mother and teacher reports of externalising behaviour on the CBCL and TRF (Achenbach, 1991a, 1991b). To ensure independence of data, playmates were randomly assigned to two different sub-samples. The validity of this rigged game for examining individual differences in disruptive behaviour was supported (in both sub-samples) by modest but significant correlations with both mother and teacher ratings of externalising problems, and by significantly elevated SNAP ratings among children rated by mothers and teachers as showing extreme (≥95 th %) levels of externalising problems, compared with the remaining majority of children. Results: Significant gender differences in disruptive behaviour were found on all three measures: observational SNAP ratings and mother/teacher questionnaire ratings. Factors that may contribute to this gender difference are discussed. Conclusions: Our findings emphasise the importance of multi-method, multi-informant measures of disruptive behaviour, and suggest that the rigged card game used in this study is a valuable adjunct to more standard methods of rating disruptive behaviour.

Three experiments investigated conditions designed to facilitate acquisition of arbitrary conditional discriminations in 3- to 6-year-old normally developing children. In Experiment 1, 6 subjects failed to master the arbitrary match-to-sample task under conditions of differential reinforcement alone, but 7 subjects did so when instructions or instructions and sample naming were added. In Experiment 2, sample naming introduced in a blocked-trial arrangement resulted in acquisition, but only when the sample name was a nonsense syllable provided by the experimenter (5 of 7 subjects) and not when the sample name was generated by the subject (0 of 5 subjects). Experiment 3 demonstrated the effectiveness of a training sequence involving thematically related stimuli as an intermediate step facilitating the transition from identity to novel arbitrary relations. The difficulties in mastering arbitrary conditional discriminations shown here imply that further analyses with young children will be particularly important in efforts to investigate the development of theoretically important stimulus relations.

Methyl benzoate is a consistent product of cocaine hydrochloride exposed to humid air. The detection responses of dogs trained to detect illicit cocaine hydrochloride may be controlled by vapor from cocaine, methyl benzoate, or other constituents of illicit cocaine. The present study addressed the following questions: 1) How capable are dogs of detecting methyl benzoate compared to cocaine hydrochloride, 2) When dogs are trained to detect methyl benzoate, do they respond to cocaine hydrochloride as being the same or different from methyl benzoate. These questions were investigated using random source dogs trained and tested under laboratory conditions. Odor stimuli were generated and delivered by a vapor generation systems, the outputs from which were characterized by thermal desorption GC/MS. ONe group of dogs was trained to discriminate pharmaceutical grade and illicit cocaine hydrochloride from clean air and tested using a two lever procedure to determine their sensitivity to these substances. A second group of dogs was trained to discriminate between methyl benzoate and clean air and tested for their sensitivity to the substance. The dogs in this second group were then tested using a three lever procedure to determine their sensitivity to these substances. A second group of dogs was trained to discriminate between methyl benzoate and clean air and tested for their sensitivity to the substance. The dogs in this second group were then tested using a three lever procedure to determine whether they responded to cocaine hydrochloride as the same or different from methyl benzoate.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.