Modification of chiral dimethyl tartrate through transesterification : immobilisation on POSS and enantioselectivity reversion in Sharpless asymmetric epoxidation

Modification of dimethyl tartrate has been investigated through transesterification with aminoalcohols to provide reactive functionalities for the covalent bonding of chiral tartrate to polyhedral oligomeric silsesquioxanes. The transesterification of dimethyl tartrate has been widely studied by means of using different catalytic systems and reaction conditions. Through the proper selection of both, the catalytic system and the reaction conditions, it is possible to achieve the mono- or the bis-substituted tartrate derivative as sole products. All the intermediate chiral tartrate-derived ligands were successfully used in the homogeneous enantioselective epoxidation of allylic alcohols providing moderate enantiomeric excess over the products. Attached amine groups have been used to support the modified tartrate ligands onto a haloaryl-functionalized silsesquioxane moiety. This final chiral tartrate ligand displays enantioselectivity reversion in the asymmetric epoxidation of allylic alcohols with regards to the starting dimethyl tartrate ligand, having both molecules them the same chiral sign. However, the POSS-containing ligand can be easily recovered in almost quantitative yield and reused in asymmetric epoxidation reactions. In addition, recovered silsesquioxane-pendant ligand, though displaying decreasing catalytic activity in recycling epoxidation tests, showed very stable enantioselective behavior

Release experiments with Octopus vulgaris Cuvier, 1797 in Galicia, NW Spain. First results on recapture rate, distribution and growth.

This paper describes the release experiments carried out with 465 octopus (Octopus vulgaris Cuvier, 1797) with an average weight ranging from 703 to 986 g in three different areas in the Ría of Vigo, Galicia, NW Spain. Thirty-seven individuals were recaptured by fishermen, representing a total recapture rate of 7.9 %. Among these, 80.5 % remained within 5 km of the release point, showing a sedentary behavior. The specific growth rate (SGR) in weight was 0.00902 ± 0.00468; there was not a significant difference between males and females. The exponential growth curve is the best fitting theoretical model. Life expectancy in Ría de Vigo waters was estimated at 18 months for males, and 16 months for females. Throughout the recapture process, males were predominant over females, giving a sex ratio of 1.83:1. Data reported in this paper on recapture rate, sedentary behavior and instantaneous growth rate can be used as reference for future stocking programs in Galicia

Culture viability of Sarddina pilchardus: preliminary results of growth in captivity

Larvae of Sardina pilchardus were obtained in captivity from fertilized eggs captured in the wild, and grown in a 10 000 L tank. Isochrysis galbana , Artemia franciscana nauplii and live zooplankton were used as prey during the first two weeks; afterwards, anim als were fed on artemia metanauplius enriched with Isochrysis galbana . A dry feed (Gemma 0.4 and 0.8) from SKRETTING S.A. (Burgos, España) was supplied from the third to 18th month. The total length reached by sardines at one year of life was 162.02 ± 9. 49 mm, corresponding to a wet weight of 36.12 ± 10.82 g. Total length at 18 months was 182.37 mm. A long experiment (18 ‐ month) of sardine culture is described for the first time, and growth data reported can contribute to determine its potential interest as a candidate for marine aquacultur

Culture viability of Sardine pilchardus (Fish, teleost): Preliminary results of growth in captivity up to 18 months

Larvae of Sardina pilchardus were obtained in captivity from fertilized eggs captured in the wild and grown in a 10000-L tank. Isochrysis galbana, Artemia franciscana nauplii and live zooplankton were used as prey during the first two weeks; afterwards, the animals were fed on Artemia metanauplii enriched with Isochrysis galbana. A dry feed (Gemma 0.4 and 0.8) from Skretting S.A. (Burgos, España) was supplied from the 3rd to the 18th month. The total length reached by sardines at one year of life was 162.02±9.49 mm, corresponding to a wet weight of 36.12±10.82 g. Total length of the last survivor individual at 18 months was 182.37 mm. An 18-month experiment of sardine culture is described for the first time, and the growth data reported can help to determine its potential as a candidate for marine aquaculture.Publicado

Results of the Spanish Experimental Fishing in NAFO Subarea 1

An experimental fishing was carried out with a commercial Spanish vessel from October to December of the year 2003 in the Subarea 1. The main objective of the experimental fishing was to search for cephalopods species concentrations inside the territorial waters of Greenland. During the experimental fishing a scientific observer stayed on board to collect effort data, catches and yields by haul and Division, strata and gear. The observer carried out length distributions samplings of the following species: Pandalus borealis, Sebastes spp., Hippoglossoides platessoides, Gadus morhua and Macrourus berglax. Biological samplings of Reinhardtius hippoglossoides, Hippoglossoides platessoides, Gadus morhua and Gadus ogac were also carried out. Greenland halibut was the main species caught and the cephalopods, target species, have not been found in the experimental fishing

Coastal morphodynamic emulator for early warning short-term forecasts

- Name of the Software: XBeach version 1.23. Developers: Deltares/XBeach Open-Source Community; First year available: 2009; Cost: Free; Software availability:https://download.deltares.nl/en/download/xbeach-open-source/; Program size: 330.97 MB. - The deep learning-based emulator used for surrogating the XBeach morphodynamic module was implemented in Python language (version 3.9) based on TensorFlow library. The authors used a Windows 11 Home OS environment, CPU Intel(R) Core (TM) i7-8750H 2.20 GHz, RAM 16 GB, GPU Nvidia GeForce GTX 1060. The architecture of the model is available at: http://www.hydroshare.org/resource/b4ae97df748842a1800816b32a3d640 b.Data will be made available on request. Deep learning model for XBeach morphodynamic emulation (Original data) (HydroShare): https://www.hydroshare.org/resource/b4ae97df748842a1800816b32a3d640b/The use of numerical models to anticipate the effects of floods and storms in coastal regions is essential to mitigate the damages of these natural disasters. However, local studies require high spatial and temporal resolution numerical models, limiting their use due to the involved high computational costs. This constraint becomes even more critical when these models are used for real-time monitoring and warning systems. Therefore, the objective of this paper was to reduce the computational time of coastal morphodynamic models simulations by implementing a deep learning emulator. The emulator performance was evaluated using different scenarios run with the XBeach software, which considered different grid resolutions and the effects of a storm event in the morphodynamic patterns around a breakwater and a groin. The morphodynamic simulation time was reduced by 23%, and it was identified that the major restriction to reducing the computational cost was the hydrodynamic numerical model simulation.This research was supported by the Doctoral Grant SFRH/BD/151383/2021 financed by the Portuguese Foundation for Science and Technology (FCT), and with funds from the Ministry of Science, Technology and Higher Education, under the MIT Portugal Program. I. Iglesias also acknowledge the FCT financing through the CEEC program (2022.07420. CEECIND)

Linking short- to medium-term beach dune dynamics to local features under wave and wind actions: a northern portuguese case study

Many coasts suffer from prevailing erosion, with them being particularly vulnerable to predicted climate change impacts, threatening coastal ecosystems, their services, infrastructures and populations. Understanding coastal morpho-sedimentary dynamics is thus essential for coastal management. However, coastal vulnerability may differ locally, depending on exposure/protection and local geological and morpho-hydrodynamical features, suggesting that a local approach to erosion risk assessment is needed to identify and understand local patterns. Digital elevation models of a 14 km long coastal stretch in northern Portugal that were extracted from aerial surveys obtained between November 2008 and February 2019 were analysed to quantify changes in shoreline position and sediment budgets, both for the whole study area and for distinct beach segments. The observed dynamics were subsequently analysed by considering prevailing wave and wind intensities and directions. Overall and during the decade analysed, the beach–dune system of the studied stretch slightly increased in volume (0.6%), although the shoreline retreated (by 1.6 m on average). Temporal variability in coastal dynamics was observed at all of the temporal scales considered—from seasons to 5-year periods—with them being related to variability in ocean and wind patterns. There was a trend from accretional to erosional conditions, with the first 5-year period showing a mean increase in the beach–dune system’s volume of 0.6% and a mean shoreline progradation of 1.5 m, followed by 5-years with 0.0% volume change and 3.1 m shoreline retreat. Locally, the dynamics were very variable, with shoreline dynamics ranging from 24.0 m regression to 51.5 m progradation, and sediment budgets from 213.8 m3 loss to 417.0 m3 gain, per segment and for the decade. Stretches with relatively stable morphologies and others with erosional or accretional trends were found, depending on the beach type, shoreline orientation and the presence of defence structures. Rocky beaches were the least dynamic and sandy beaches the most dynamic, with mean shoreline position changes of 0.0 m and −3.4 m, respectively, and mean sediment budgets of −1.1 m3 and −2.9 m3 per linear meter of coastline, respectively, for the studied decade. The observed dynamics showed how local conditions interacted with meteo-ocean conditions in shaping local morpho-sedimentary dynamics, stressing the importance of a local approach to coastal erosion monitoring and risk assessment.European Union MarRISK project: Adaptación costera ante el Cambio Climático: conocer los riesgos y aumentar la resiliencia (0262_MarRISK_1_E) through EP INTERREG V A España-Portugal (POCTEP) program and the project INNOVMAR-Innovation and Sustainability in the Management and Exploitation of Marine Resources (NORTE-01-0145-FEDER-000035, within Research Line ECOSERVICES), supported by NORTE 2020, under the PORTUGAL 2020 Partnership Agreement, through the ERD

Particle methods parallel implementations by GP-GPU strategies

This paper outlines the problems found in the parallelization of SPH (Smoothed Particle Hydrodynamics) algorithms using Graphics Processing Units. Different results of some parallel GPU implementations in terms of the speed-up and the scalability compared to the CPU sequential codes are shown. The most problematic stage in the GPU-SPH algorithms is the one responsible for locating neighboring particles and building the vectors where this information is stored, since these specific algorithms raise many difficulties for a data-level parallelization. Because of the fact that the neighbor location using linked lists does not show enough data-level parallelism, two new approaches have been proposed to minimize bank conflicts in the writing and subsequent reading of the neighbor lists. The first strategy proposes an efficient coordination between CPU-GPU, using GPU algorithms for those stages that allow a straight forward parallelization, and sequential CPU algorithms for those instructions that involve some kind of vector reduction. This coordination provides a relatively orderly reading of the neighbor lists in the interactions stage, achieving a speed-up factor of x47 in this stage. However, since the construction of the neighbor lists is quite expensive, it is achieved an overall speed-up of x41. The second strategy seeks to maximize the use of the GPU in the neighbor’s location process by executing a specific vector sorting algorithm that allows some data-level parallelism. Although this strategy has succeeded in improving the speed-up on the stage of neighboring location, the global speed-up on the interactions stage falls, due to inefficient reading of the neighbor vectors. Some changes to these strategies are proposed, aimed at maximizing the computational load of the GPU and using the GPU texture-units, in order to reach the maximum speed-up for such codes. Different practical applications have been added to the mentioned GPU codes. First, the classical dam-break problem is studied. Second, the wave impact of the sloshing fluid contained in LNG vessel tanks is also simulated as a practical example of particle methods

Analysis of estuarine flood levels based on numerical modelling. The Douro river estuary case study

Estuarine hydrodynamics present intermittent and complex circulation patterns. In this context, from the point of view of the coastal management associated with flood risks in riverine areas, numerical models allow predicting scenarios under specific hypotheses. This work simulates flood events occurring in the Douro river estuary recurring to numerical modelling tools. This estuary, located in the northern region of Portugal, periodically suffered severe flooding, with the associated losses and damages for the local protected landscape areas and hydraulic structures. The occurrence of these events justify the importance of a complete characterization of the areas that present risk of inundation and how they can be affected. A 2D-horizontal numerical model implemented with the Delft3D software was developed for this estuarine region including also the adjacent coastal zone. Available in-situ data were used for model calibration and validation processes. The obtained results are consistent with the in-situ measured water levels, allowing to understand the dynamics of the estuary during flood events. The robustness of the implemented numerical model allows to anticipate flood scenarios effects and associated water levels. The simulations results can then be used for sustainable management of this estuarine zone that presents high social, economic and environmental values.This research was partially supported by the Research Line ECOSERVICES, integrated in the Structured Program of R&D&I INNOVMAR: Innovation and Sustainability in the Management and Exploitation of Marine Resources (NORTE-01- 0145-FEDER-000035), funded by the Northern Regional Operational Programme (NORTE2020) through the European Regional Development Fund (ERDF), and by the Brazilian National Council for Scientific and Technological Development (CNPq) through a scholarship granted to the 1st author (Process 200016 / 2014-8)

Simulation of saltwater intrusion in the Minho river estuary under sea level rise scenarios

Estuaries are areas that are vulnerable to the impacts of climate change. Understanding how these impacts affect these complex environments and their uses is essential. This paper presents a work based on an analytical solution and 2DH and 3D versions of the Delft3D numerical model to simulate the Minho River estuary and its saline wedge length under climate change projections. Temperature observations at several locations in the estuary region were selected to determine which model better simulated the temperature patterns. Specific simulations were performed for the observation periods. Sixteen numerical model scenarios were proposed, considering a varying tide, different river flows, and several SLR projections based on the RCP4.5 and RCP8.5 for 2050 and 2100. The analytical solution was also calibrated using the numerical model solutions. The results show that although there is no relevant stratification, there was a difference in both models in which in the worst climate change scenario, the length of the saline intrusion increased up to 28 km in the 2DH model and 30 km in the 3D model. It was concluded that the 3D model results were more precise, but both configurations can provide insights into how the saline intrusion will be affected. Additionally, the excellent agreement between the analytical solution and the results of the numerical models allowed us to consider the analytical solution a helpful tool for practical applications. It was demonstrated that freshwater discharges and bed slopes are the most critical drivers for the saline intrusion length in the Minho River estuary as they have more impact than the increase in sea level. Therefore, flow regulation can be an excellent way to control saline intrusion in the future.NNI -Nortel Networks Inc(2022.07420