Advancing fishery-independent stock assessments for the Norway lobster (Nephrops norvegicus) with new monitoring techn

The Norway lobster, Nephrops norvegicus, supports a key European fishery. Stock assessments for this species are mostly based on trawling and UnderWater TeleVision (UWTV) surveys. However, N. norvegicus are burrowing organisms and these survey methods are unable to sample or observe individuals in their burrows. To account for this, UWTV surveys generally assume that “1 burrow system = 1 animal”, due to the territorial behavior of N. norvegicus. Nevertheless, this assumption still requires in-situ validation. Here, we outline how to improve the accuracy of current stock assessments for N. norvegicus with novel ecological monitoring technologies, including: robotic fixed and mobile camera-platforms, telemetry, environmental DNA (eDNA), and Artificial Intelligence (AI). First, we outline the present status and threat for overexploitation in N. norvegicus stocks. Then, we discuss how the burrowing behavior of N. norvegicus biases current stock assessment methods. We propose that state-of-the-art stationary and mobile robotic platforms endowed with innovative sensors and complemented with AI tools could be used to count both animals and burrows systems in-situ, as well as to provide key insights into burrowing behavior. Next, we illustrate how multiparametric monitoring can be incorporated into assessments of physiology and burrowing behavior. Finally, we develop a flowchart for the appropriate treatment of multiparametric biological and environmental data required to improve current stock assessment methods

WORKING GROUP ON NEPHROPS SURVEYS (WGNEPS ; outputs from 2020)

The Working Group on Nephrops Surveys (WGNEPS) is the international coordination group for Nephrops underwater television and trawl surveys within ICES. This report summarizes the na-tional contributions on the results of the surveys conducted in 2020 together with time series covering all survey years, problems encountered, data quality checks and technological improve-ments as well as the planning for survey activities for 2021.ICE

Cut-offs and response criteria for the Hospital Universitario la Princesa Index (HUPI) and their comparison to widely-used indices of disease activity in rheumatoid arthritis

Objective To estimate cut-off points and to establish response criteria for the Hospital Universitario La Princesa Index (HUPI) in patients with chronic polyarthritis. Methods Two cohorts, one of early arthritis (Princesa Early Arthritis Register Longitudinal PEARL] study) and other of long-term rheumatoid arthritis (Estudio de la Morbilidad y Expresión Clínica de la Artritis Reumatoide EMECAR]) including altogether 1200 patients were used to determine cut-off values for remission, and for low, moderate and high activity through receiver operating curve (ROC) analysis. The areas under ROC (AUC) were compared to those of validated indexes (SDAI, CDAI, DAS28). ROC analysis was also applied to establish minimal and relevant clinical improvement for HUPI. Results The best cut-off points for HUPI are 2, 5 and 9, classifying RA activity as remission if =2, low disease activity if >2 and =5), moderate if >5 and <9 and high if =9. HUPI''s AUC to discriminate between low-moderate activity was 0.909 and between moderate-high activity 0.887. DAS28''s AUCs were 0.887 and 0.846, respectively; both indices had higher accuracy than SDAI (AUCs: 0.832 and 0.756) and CDAI (AUCs: 0.789 and 0.728). HUPI discriminates remission better than DAS28-ESR in early arthritis, but similarly to SDAI. The HUPI cut-off for minimal clinical improvement was established at 2 and for relevant clinical improvement at 4. Response criteria were established based on these cut-off values. Conclusions The cut-offs proposed for HUPI perform adequately in patients with either early or long term arthritis

The comparative responsiveness of Hospital Universitario Princesa Index and other composite indices for assessing rheumatoid arthritis activity

Objective To evaluate the responsiveness in terms of correlation of the Hospital Universitario La Princesa Index (HUPI) comparatively to the traditional composite indices used to assess disease activity in rheumatoid arthritis (RA), and to compare the performance of HUPI-based response criteria with that of the EULAR response criteria. Methods Secondary data analysis from the following studies: ACT-RAY (clinical trial), PROAR (early RA cohort) and EMECAR (pre-biologic era long term RA cohort). Responsiveness was evaluated by: 1) comparing change from baseline (Delta) of HUPI with Delta in other scores by calculating correlation coefficients; 2) calculating standardised effect sizes. The accuracy of response by HUPI and by EULAR criteria was analyzed using linear regressions in which the dependent variable was change in global assessment by physician (Delta GDA-Phy). Results Delta HUPI correlation with change in all other indices ranged from 0.387 to 0.791); HUPI's standardized effect size was larger than those from the other indices in each database used. In ACT-RAY, depending on visit, between 65 and 80% of patients were equally classified by HUPI and EULAR response criteria. However, HUPI criteria were slightly more stringent, with higher percentage of patients classified as non-responder, especially at early visits. HUPI response criteria showed a slightly higher accuracy than EULAR response criteria when using Delta GDA-Phy as gold standard. Conclusion HUPI shows good responsiveness in terms of correlation in each studied scenario (clinical trial, early RA cohort, and established RA cohort). Response criteria by HUPI seem more stringent than EULAR''s

Acoustic underwater target tracking methods using autonomous vehicles

Memoria de tesis doctoral presentada por Ivan Masmitjà Rusiñol para obtener el título de Doctor por la Universitat Politècnica de Catalunya (UPC), realizada bajo la dirección del Dr. Spartacus Gomáriz Castro de la Universitat Politècnica de Catalunya (UPC) y el Dr. Jacopo Aguzz del Institut de Ciències del Mar (ICM-CSIC).-- 192 pages, figures, tablesMarine ecological research related to the increasing importance which the fisheries sector has reached so far, new methods and tools to study the biological components of our oceans are needed. The capacity to measure different population and environmental parameters of marine species allows a greater knowledge of the human impact, improving exploitation strategies of these resources. For example, the displacement capacity and mobility patterns are crucial to obtain the required knowledge for a sustainable management of fisheries. However, underwater localisation is one of the main problems which must be addressed in subsea exploration, where no Global Positioning System (GPS) is available. In addition to the traditional underwater localisation systems, such as Long BaseLine (LBL) or Ultra-Short BaseLine (USBL), new methods have been developed to increase navigation performance, flexibility, and to reduce deployment costs. For example, the Range-Only and Single-Beacon (ROSB) is based on an autonomous vehicle which localises and tracks different underwater targets using slant range measurements conducted by acoustic modems. In a moving target tracking scenario, the ROSB target tracking method can be seen as a Hidden Markov Model (HMM) problem. Using Bayes’ rule, the probability distribution function of the HMM states can be solved by using different filtering methods. Accordingly, this thesis presents different strategies to improve the ROSB localisation and tracking methods for static and moving targets. Determining the optimal parameters to minimize acoustic energy use and search time, and to maximize the localisation accuracy and precision, is therefore one of the discussed aspects of ROSB. Thus, we present and compare different methods under different scenarios, both evaluated in simulations and field tests. The main mathematical notation and performance of each algorithm are presented, where the best practice has been derived. From a methodology point of view, this work advances the understanding of accuracy that can be achieved by using ROSB target tracking methods with autonomous vehicles. [...

Underwater Multi-Target Tracking with Particle Filters

5 pages, 8 figures, 1 table.-- © 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksRobotic platforms communication and interoperability is of relevance for marine science and industrial monitoring. We present results of a particle filter study based on underwater Multi-Target Tracking (MTT) using Autonomous Underwater Vehicles (AUV). The main goal was to assess the viability of using a single surface vehicle as a mobile landmark to track and follow a fleet of underwater targets, each one equipped with an acoustic tag where the slant ranges between the surface vehicle and the underwater targets are the unique input for the filtersThis work was partially supported by the project JERICO-NEXT from the European Commission’s Horizon 2020 research and Innovation programme under grant agreement No 654410. We also thanks the financial support from the Spanish Ministerio de Economía y Competitividad under contract TEC2017-87861-R project RESBIOPeer Reviewe

Underwater acoustic slant range measurements related to weather and sea state

XXII World Congress of the International Measurement Confederation (IMEKO 2018), 3-6 September 2018, Belfast, United Kingdom.-- 4 pages, 6 figuresUnderwater range measurements are key factor in underwater acoustic positioning, used in Long Base-Line (LBL) or Ultra Short Base-Line (USBL) computing techniques. These measurements are commonly carried out through acoustic communications between modems and their accuracy can be affected by different factors, such as sea state, weather conditions, and obstacles in the line of sight propagation. This is especially important in shallow waters areas, where others phenomena such as multi-path have to be considered. Therefore, range accuracy and the associated position estimation errors are an important area of research. Here, we addressed the relation between range measurements variability and sea state (i.e. currents or waves height) as proxy of real-world conditions, affecting acoustic positioning performances. For that purpose, a long-term deployment have been carried out in the underwater cabled observatory OBSEA, which provide different measurements of the sea and weather stateThis work was partially supported by the project JERICO-NEXT from the EC-H2020 under grant agreement No 654410 (EvoLUL TNA sub-project). We also thanks the financial support from the Spanish Ministerio de Economía y Competitividad under contract TEC2017-87861-R project RESBIOPeer Reviewe

Accuracy and precision studies for range-only underwater target tracking in shallow waters

22nd IMEKO TC4 International Symposium & 20th International Workshop on ADC Modelling and Testing, 14-15 September 2017, Iaşi, Romania.-- 6 pages, 8 figures, 1 tableThis paper studies the precision, and the accuracy, of an underwater target tracking system, using range-only and single-beacon methods, in shallow waters environments. For this study, different field tests have been realized in the OBSEA test site, a well-known and monitored area at 4 km from the coast and at 20 meters of depth, in the Mediterranean Sea (Barcelona). The tests have been conducted using two acoustic underwater modems from the company LinkQuest Inc. Moreover, the autonomous underwater vehicle developed by the Universitat Politècnica de Catalunya (called Guanay II) have also used to perform the testsThis work was partially supported by the project NeXOS from the European Union’s Seventh Programme for research, technological development and demonstration under the grant agreement No 614102. We also had financial support from the Spanish Ministerio de Economía y Competitividad under contract CGL2013-42557-R (Interoperabilidad e instrumentación de plataformas autónomas marinas para la monitorización sísmica, INTMARSIS) and CTM2015-68804-REDT (Instrumentation and Applied Technology for the Study, Characterization and Sustainable Exploration of Marine Environment, MarInTech)Peer Reviewe

New Vectorial Propulsion System and Trajectory Control Designs for Improved AUV Mission Autonomy

26 pages, 27 figures, 2 tablesAutonomous Underwater Vehicles (AUV) are proving to be a promising platform design for multidisciplinary autonomous operability with a wide range of applications in marine ecology and geoscience. Here, two novel contributions towards increasing the autonomous navigation capability of a new AUV prototype (the Guanay II) as a mix between a propelled vehicle and a glider are presented. Firstly, a vectorial propulsion system has been designed to provide full vehicle maneuverability in both horizontal and vertical planes. Furthermore, two controllers have been designed, based on fuzzy controls, to provide the vehicle with autonomous navigation capabilities. Due to the decoupled system propriety, the controllers in the horizontal plane have been designed separately from the vertical plane. This class of non-linear controllers has been used to interpret linguistic laws into different zones of functionality. This method provided good performance, used as interpolation between different rules or linear controls. Both improvements have been validated through simulations and field tests, displaying good performance results. Finally, the conclusion of this work is that the Guanay II AUV has a solid controller to perform autonomous navigation and carry out vertical immersions.This work was partially supported by the project JERICO-NEXTfrom the European Commission’s Horizon 2020 research and Innovation program under Grant Agreement No. 654410. We would also like to thank the Spanish Ministerio de Economia y Competitividad under contract for the Spanish thematic network MarInTech (Ref. CTM 2015-68804-REDT (Instrumentation and Applied Technology for the Study, Characterization and Sustainable Exploration of Marine Environment, MarInTech)) for their financial supportPeer Reviewe

Range-Only Single-Beacon Tracking of Underwater Targets From an Autonomous Vehicle: From Theory to Practice

18 pages, 13 figures, 10 tablesUnderwater localization is one of the main problems that must be addressed in subsea exploration, where no global positioning system (GPS) is available. In addition to the traditional underwater localization systems, such as long base line (LBL), new methods have been developed to increase the navigation performance and flexibility and to reduce the deployment costs. For example, range-only and single-beacon (ROSB) is based on an autonomous vehicle that localizes and tracks different underwater targets using slant range measurements carried out with acoustic modems. This paper presents different strategies to improve ROSB tracking methods. The ROSB target tracking method can be seen as a hidden Markov model (HMM) problem. Using Bayes' rule, the probability distribution function of the HMM states can be solved by using different filtering methods. Here, we present and compare different methods under different scenarios, both evaluated in simulations and field tests. The main mathematical notation and performance of each algorithm are presented, where best practice has been derived. From a methodological point of view, this paper advanced the understanding of accuracy that can be achieved by using the ROSB target tracking methods with autonomous underwater vehiclesThis work was supported in part by the JERICO-NEXT project of the EC-H2020 under Grant 654410, in part by the EvoLUL TNA sub-project, in part by the Spanish Ministerio de Economía y Competitividad, through the RESBIO project, under Contract TEC2017-87861-R, and in part by the Generalitat de Catalunya Sistemas de Adquisición Remota de datos y Tratamiento de la Información en el Medio Marino (SARTI-MAR) 2017 SGR 376. The work of I. Masmitja was supported by the FPI-UPC Scholarship from the Universitat Politècnica de Catalunya (UPC) under Grant Agreement 175/2015Peer Reviewe