TENTH WORKSHOP ON THE DEVELOPMENT OF QUANTITATIVE ASSESSMENT METHODOLOGIES BASED ON LIFE-HISTORY TRAITS, EXPLOITATION CHARACTERISTICS, AND OTHER RELEVANT PARAMETERS FOR DATA-LIMITED STOCKS (WKLIFE X)

The Workshop on the Development of Quantitative Assessment Methodologies based on Life history traits, exploitation characteristics, and other relevant parameters for data-limited stocks (WKLIFE X), chaired by Carl O'Brien (UK) and Manuela Azevedo (Portugal) met virtually 5–9 October 2020, to further develop methods for stock assessment and catch advice for stocks in Categories 3 and 4, focusing on the provision of sound advice rules that are within the ICES MSY framework. This tenth workshop was convened to further address the challenges to the evidence base for the provision of ICES advice with specific reference to data-limited stocks. There is an increasing number of fish stocks in Categories 3 and 4 for which assessment of status relative to MSY proxy reference points is available but for which short-term forecasts and MSY-based ad vice are not available. For assessments using the stochastic surplus production model in contin uous time (SPiCT), WKLIFE X developed and evaluated ‘fractile rules’ that account for uncer tainty and allow to consider any percentile and demonstrated that ‘fractile rules’ are more effec tive and precautionary than the median rule (50th percentile) and the ‘2-over-3’ rule. Additional work on advice rules for stocks in Category 3 based on life-history traits (k), tested through sim ulation and management strategy evaluation (MSE), showed that the addition of specific multi pliers based on the stock’s life-history characteristics decreases the risk of the control rule´s per formance. Annex 3 to this report contains the revised technical guidance on methods and advice rules for stocks in Category 3. The revision of the accumulated decade of ICES documentation on methods and advice for data-limited stocks into a stand-alone technical guidance document requires significant effort and dedicated work beyond the time available at the WKLIFE X meet ing. It is proposed that a dedicated workshop be established to undertake and complete the up dating and revision into a single reference documentICES, U

Optically addressing interaction of Mg/MgO plasmonic systems with hydrogen

Magnesium-based films and nanostructures are being studied in order to improve hydrogen reversibility, storage capacity, and kinetics, because of their potential in the hydrogen economy. Some challenges with magnesium (Mg) samples are their unavoidable oxidation by air exposure and lack of direct in situ real time measurements of hydrogen interaction with Mg and MgO surfaces and Mg plasmonic nanoparticles. Given these challenges, the present article investigates direct interaction of Mg with hydrogen, as well as implications of its inevitable oxidation by real-time spectroscopic ellipsometry for exploiting the optical properties of Mg, MgH2 and MgO. The direct hydrogenation measurements have been performed in a reactor that combines a remote hydrogen plasma source with an in situ spectroscopic ellipsometer, which allows optical monitoring of the hydrogen interaction and results in optical property modification. The hydrogen plasma dual use is to provide the hydrogen-atoms and to reduce barriers to heterogeneous hydrogen reactions.European Commission under the H2020 grant TWINFUSYON (GA692034). Army Research Laboratory under Cooperative Agreement Number W911NF-17-2-0023. SODERCAN (Sociedad para el Desarrollo de Cantabria) through the Research Vicerrectorate of the University of Cantabria

Fertilización nitrogenada en olivo cv. Empeltre. II.- composición polifenólica de hojas y frutos y calidad del aceite

4 Pags.- 1 Tabl.- 3 Figs.El establecimiento de posibles relaciones entre el estado nutricional del olivo, la composición polifenólica de sus hojas y frutos y la calidad del aceite, sólo puede llevarse a cabo en experimentos de fertilización controlados, donde se estudie el efecto de un sólo elemento nutriente, manteniendo constantes todos los demás parámetros agronómicos. Este es el objetivo del presente trabajo. Realizar un estudio de este tipo, es tarea compleja, interdisciplinar, y exige un largo periodo de tiempo de observación y seguimiento. Nuestro equipo la ha abordado, aunque consciente de que no se puede llegar en corto plazo a resultados concluyentes. La reconocida calidad de los aceites de Aragón (GRACIA, 1991, 1996, 2001) y la peculiaridad de las principales variedades aquí implantadas, Empeltre y Arbequina, han motivado la puesta en marcha de dos experimentos de fertilización con árboles jóvenes (uno en cada variedad), que puedan contribuir a mejorar su conocimiento. En dos trabajos previos (MONGE et al., 2002 a y b) se da cuenta de los datos relativos a cada uno de los experimentos, así como de los primeros resultados del estudio de los suelos, del estado nutritivo de los árboles y del crecimiento de éstos. El presente trabajo sintetiza los primeros datos obtenidos en el ensayo de fertilización nitrogenada con la variedad Empeltre sobre el contenido de los polifenoles en hoja y fruto y sobre la calidad del aceite.Este trabajo ha sido subvencionado por el MAPA, Programa de Mejora de la Calidad de la Producción de Aceite de Oliva, proyecto CAO99-020-C2.Peer reviewe

Sustainable and tunable Mg/MgO plasmon-catalytic platform for the grand challenge of SF6 environmental remediation

Sulfur hexafluoride (SF₆) is one of the most harmful greenhouse gases producing environmental risks. Therefore, developing ways of degrading SF₆ without forming hazard products is increasingly important. Herein we demonstrate for the first time the plasmon-catalytic heterogeneous degradation of SF₆ into non-hazardous MgF₂ and MgSO₄ products by non-toxic and sustainable plasmonic magnesium/magnesium oxide (Mg/MgO) nanoparticles, which are also effective as a plasmonenhanced SF₆ chemometric sensor. The main product depends on the excitation wavelength; when the localized surface plasmon resonance (LSPR) is in the ultraviolet then MgF₂ forms, while visible light LSPR results in MgSO₄. Furthermore, Mg/MgO platforms can be regenerated in few seconds by hydrogen plasma treatment and can be re-used in a new cycle of air purification. Therefore, this research first demonstrates effectiveness of Mg/MgO plasmoncatalysis enabling environmental remediation with the concurrent functionalities of monitoring, degrading and detecting sulfur- and fluorine- gases in the atmosphere.Y.G., F.G. and F.M. acknowledge MICINN (Spanish Ministry of Science and Innovation) through project PGC2018-096649-B-100. Y.G. thanks the University of Cantabria for her FPU grant

Estimating life history parameters of European hake using Bayesian models

Sustainability and Maximum Sustainable yield (MSY) are nowadays the main fishery management goals, which are mainly addressed through single stock assessment models. However, there is a need of increasing the number of stocks assessed and improve the quality of existing assessments. The stock assessment is based on models that link the fishing activity to population dynamics based on biological processes. A common problem when starting to develop a stock assessment model for a specific species is that the biological knowledge for some processes is poor or even absent (frequently for M but also growth). In these cases, the lack of prior knowledge can be replaced with empirical estimates. The theory of life history invariants states (in general) that for a similar taxa, k/M and Lm/Linf tend to be relatively constant. This theory highlights two helpful considerations: one that whether you know one parameter you can estimate the other and two that those parameters cannot vary since they are correlated. Within this frame, life history invariants theory and hierarchical Bayesian models can be combined to better understand biological processes needed in most stock assessment models (maturity, growth and natural mortality) providing the required parameters together with their statistical structure (posterior distributions). In order to perform this meta-analysis, bibliographic life history parameters for different hake species all over the world have been collected and analysed. The results of these parameters could be useful to help in the configuration of biological processes of hake stock assessment models