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Ocean observations are critical in developing our understanding of the interaction between the ocean and climate. Detailed information about the nutrient composition of the ocean is achieved using in situ sensing and the collection and analysis of physical samples from research vessels. The analysis of nutrients underpins work in understanding both the carbon cycle and biological productivity in oceans. Although in situ sensors are becoming more common for some nutrients, the best and most reliable method for making these measurements is to conduct analysis of physical samples at sea. This article discusses the analysis and data processing methods developed by the hydrochemistry team at Commonwealth Scientific and Industrial Research Organisation (CSIRO) to provide repeatable and accurate analysis of nutrient samples at sea. Nutrients are measured by segmented flow analysis and data are processed using in‐house software (Hydrology Processor [HyPro]). These methods were used during the Global Ocean Ship‐based Hydrographic Investigations Program (GO‐SHIP) P15S voyage in 2016. Accuracy and precision of the analyses during the voyage was determined from measurement of the certified reference material for nutrients in seawater (RMNS) for silicate, phosphate, nitrate, and nitrite and is presented and discussed here. The accuracy of the silicate and phosphate RMNS measurements was within 1–3% of the certified values, and nitrate + nitrite within 1–2%. The precision for silicate, nitrate + nitrite, and phosphate was greater than 0.2%. The hydrochemistry team has established a standard operating procedure which assures the quality of nutrient data obtained is accurate and precise. [ABSTRACT FROM AUTHOR]

The article offers information on research related to the semantic processing of words and objects conducted by Barry J. Devereux and colleagues. Topics include input modality and semantic representations, functional magnetic resonance imaging to study neural processing, and activity in parts of the brain including the left posterior middle temporal gyrus, the left angular gyrus, and the left interparietal sulcus.

Light Detection and Ranging (LiDAR), a comparatively new technology in the field of underwater surveying, has principally been used for taking precise measurement of undersea structures in the oil and gas industry. Typically, the LiDAR is deployed on a remotely operated vehicle (ROV), which will "land" on the seafloor in order to generate a 3D point cloud of its environment from a stationary position. To explore the potential of subsea LiDAR on a moving platform in an environmental context, we deployed an underwater LiDAR system simultaneously with a multibeam echosounder (MBES), surveying Kingston Reef off the coast of Rottnest Island, Western Australia. This paper compares and summarises the relative accuracy and characteristics of underwater LiDAR and multibeam sonar and investigates synergies between sonar and LiDAR technology for the purpose of benthic habitat mapping and underwater simultaneous localisation and mapping (SLAM) for Autonomous Underwater Vehicles (AUVs). We found that LiDAR reflectivity and multibeam backscatter are complementary technologies for habitat mapping, which can combine to discriminate between habitats that could not be mapped with either one alone. For robot navigation, SLAM can be effectively applied with either technology, however, when a Global Navigation Satellite System (GNSS) is available, SLAM does not significantly improve the self-consistency of multibeam data, but it does for LiDAR. [ABSTRACT FROM AUTHOR]