Performance of a novel system for high-resolution tracking of marine fish societies

Recent advances in tracking systems have revolutionized our ability to study animal movement in the wild. In aquatic environments, high-resolution acoustic telemetry systems make it technically possible to simultaneously monitor large amounts of individuals at unprecedented spatial and temporal resolutions, providing a unique opportunity to study the behaviour and social interactions using a reality mining approach. Despite the potential, high-resolution telemetry systems have had very limited use in coastal marine areas due to the limitations that these environments pose to the transmission of acoustic signals. This study aims at designing and testing a high-resolution acoustic telemetry system to monitor, for the first time, a natural fish population in an open marine area. First, we conducted preliminary range tests and a computer simulation study to identify the optimal design of the telemetry system. Then, we performed a series of stationary and moving tests to characterize the performance of the system in terms of positioning efficiency and precision. Finally, we obtained a dataset corresponding to the movements of 170 concurrently tagged individuals to demonstrate the overall functioning of the system with a real study case of the behaviour of a small-bodied coastal species. Our results show that high-resolution acoustic telemetry systems efficiently generate positional data in marine systems, providing a precision of few meters, a temporal resolution of few seconds, and the possibility of tracking hundreds of individuals simultaneously. Data post-processing using a trajectory filter and movement models proved to be key to achieve a sub-meter positioning precision. The main limitation detected for our system was the restricted detection range, which was negatively affected by the stratification of the water column. Our work demonstrates that high-resolution acoustic telemetry systems are an effective method to monitor the movements of free-ranging individuals at the population level in coastal sites. By providing highly precise positioning estimates of large amounts of individuals, these systems represent a powerful tool to study key ecological processes regarding the social interactions of individuals, including social dynamics, collective movements, or responses to environmental perturbations, and to extend the studies to poorly studied small-sized species or life-stages.The telemetry system was financed by the German Federal Ministry of Education and Research (grant no. #033W024A). EA was supported by a Margalida Comas postdoctoral grant from the Government of the Balearic Islands and the European Social Fund (Grant No. PD/023/2018). JA was supported by a Ramon y Cajal Grant (Grant No. RYC2018-024488-I) and received funding from the CLOCKS R&D Project (Grant No. PID2019-104940GA-I00) and the intramural research project JSATS (Grant No. PIE 202030E002) funded by the Spanish Ministry of Science and Innovation and the Spanish National Research Council. GFB was supported by a Ph.D. fellowship (FPI-INIA 2015–0013-CPD2015-0084) from the National Institute for Agricultural and Food Research and Technology.Peer reviewe

New Structured Materials in the Study of the Mechanobiological Processes Related to the Heart Failure

Cardiovascular diseases are the number one of death globally. According to the World Health organization 17.7 million people died from cardiovascular diseases in 2015, representing 31% of all global deaths.  In these diseases the cardiac homeostasis is disrupted by a non-appropriate myocardium remodelling. The cardiac extracellular matrix (ECM) provides not only the biochemical environment but also a natural scaffold surrounding and connecting cardiac cells and distributing mechanical forces throughout the organ. Thus, the properties of the ECM are essential for the maintenance of the functional myocardium. Alterations in cardiac ECM structure associated with heart failure influence cell-matrix and cell-cell adhesions modifying cell shape and mechanotransduction.The need to understand the cardiac ECM remodelling mechanisms that allow us to identify new therapeutic targets lead us to create biomimetic scaffolds which emulate the structure, topography, mechanics and chemical composition of ECM.Here, we present the development of modulable materials for the manufacturing, by using photopolymerizable materials, of structured hydrogels with myocardium properties of stiffness and elastic modulus in physiological and pathological conditions

New Structured Materials in the Study of the Mechanobiological Processes Related to the Heart Failure

Cardiovascular diseases are the number one of death globally. According to the World Health organization 17.7 million people died from cardiovascular diseases in 2015, representing 31% of all global deaths. In these diseases the cardiac homeostasis is disrupted by a non-appropriate myocardium remodelling. The cardiac extracellular matrix (ECM) provides not only the biochemical environment but also a natural scaffold surrounding and connecting cardiac cells and distributing mechanical forces throughout the organ. Thus, the properties of the ECM are essential for the maintenance of the functional myocardium. Alterations in cardiac ECM structure associated with heart failure influence cell-matrix and cell-cell adhesions modifying cell shape and mechanotransduction. The need to understand the cardiac ECM remodelling mechanisms that allow us to identify new therapeutic targets lead us to create biomimetic scaffolds which emulate the structure, topography, mechanics and chemical composition of ECM. Here, we present the development of modulable materials for the manufacturing, by using photopolymerizable materials, of structured hydrogels with myocardium properties of stiffness and elastic modulus in physiological and pathological conditions

Marine aerosols, their precursors and their influence on clouds over the global ocean

Memoria de tesis doctoral presentada por María Aránzazu Lana Celaya para optar al grado de Doctora en Ciencias del Mar en el Departament d'Enginyeria Hidràulica, Marítima i Ambiental de la Universitat Politècnica de Catalunya (UPC), realizada bajo la dirección del Dr. Rafel Simó Martorell del Institut de Ciències del Mar (ICM-CSIC) y del Dr. Jordi Dachs del Instituto de Diagnóstico Ambiental y Estudios del Agua (IDAEA-CSIC).-- 207 pagesMarine aerosols have a large potential to influence the Earth’s climate through their effects on cloud properties. The CLAW hypothesis goes further, and suggests that marine aerosols formed by the sulphur cycle of the ocean and the atmosphere act as a mechanism for regulating the Earth's climate. This effect is produced through the influence of plankton emissions of sulphur compounds on cloud formation. Phytoplankton produces dimethylsulphide (DMS), a highly volatile sulphur compound. Once in the atmosphere, DMS is oxidized and becomes the main source of natural atmospheric sulphates. These sulphates act as condensation nuclei, particles that are essential for the formation of clouds. Those marine particles in the atmosphere play an important role in the Earth's radiation budget. Indirectly they produce a greater amount of cloud droplets. Higher cloud condensation nuclei imply smaller cloud droplets. The efficiency of smaller droplets in reflecting incident solar radiation is greater, resulting in an increase in cloud albedo, producing a cooling effect on the Earth's surface. To properly study the marine aerosols we need accurate knowledge of the global seawater distribution of the aerosol precursors. Our work focused on the ocean-to-atmosphere emissions of DMS and other biogenic gases that can have an impact on cloud microphysics. During the thesis we updated the monthly global DMS climatology taking advantage of the three-fold increased size and better resolved distribution of the observations available in the DMS database. The emerging patterns found with the previous versions of the database and climatology were explored with the updated version. The statistical relationships between the seasonalities of DMS concentrations and solar radiation doses and chlorophyll a concentrations were here re-examined. Analyses of nine years of satellite data suggested that there is a natural inverse correlation between the spatial cover of low marine clouds and the cloud droplet size, which is related to the presence of small aerosols. This coupled seasonality pushes cloud albedo to contribute higher negative radiative forcing in summer and lower in winter. This relation is disrupted in the marine atmosphere regions heavily impacted by anthropogenic aerosols. Consequently, the potential influence the aerosol precursors have on marine clouds was next analysed over unpolluted and polluted ocean, separately. The 9 years of global satellite data and ocean climatologies were used to derive parameterizations of the production fluxes of secondary aerosols formed by oxidation of DMS and other biogenic organic volatiles. Further, the emission fluxes of biogenic primary organic and sea salt aerosols ejected by wind action on sea surface were also globally studied. Series of weekly estimates of these fluxes were correlated to series of cloud droplet effective radius. The outcome of the statistical analyses indicated that sulphur and organic secondary aerosols might be important in seeding cloud nucleation and droplet activation over mid and high latitude unpolluted oceanic regions. Conversely, primary aerosols (organic and sea salt) showed that, despite contributing to large shares of the marine aerosol mass, they do not seem to be major drivers of the variability of cloud microphysics. Our results provide partial support for the feasibility of the CLAW hypothesis at the seasonal scale. Despite that DMS has drawn much of the attention on the links between marine biota and climate regulation, the implication of other biogenic precursors on cloud formation provides and suggests a wider scope on the formulation of such hypothesisPeer Reviewe

Estudio de los riesgos que afectan a la patología mental, musculoesquelética y visual de los Usuarios de Pantallas de Visualización de datos

The surveillance of health allows us to analyze working conditions, in order to detect the health problems related to the job, and tries to prevent the risks derived from its execution, that can damage both health professionals and workers in general, we are trying to find the risks that cause the pathology, of the employees. This is a retrospective descriptive study of a company involved in the sale and distribution of computers. The study is conducted from medical examinations of users of PVD in 2011 .We want to know if they have medical disorders and if they are work related. The results show a higher prevalence of ocular pathology followed by muscle- skeletal. When we finished it, we informed the manager about the sample results and preventative measures The objective of this study is to know the pathology on the usage of computer terminals, related with the place of work and identify the risk factors over the health.La vigilancia de la salud permite analizar las condiciones de trabajo y el estado de salud del trabajador, con el objetivo de detectar los problemas relacionados durante su desarrollo. En este estudio tratamos de controlar los riesgos derivados de la ejecución del mismo y de identificar sus efectos sobre la salud en los usuarios de pantallas de visualización de datos (PVD), con el fin de, posteriormente, planificar una adecuada intervención para hacer frente a esos riesgos y a los futuros problemas que puedan desarrollarse. Se trata de un estudio descriptivo retrospectivo de una empresa que se dedica a la venta y distribución de ordenadores. El estudio se realiza a partir de los exámenes de salud específicos de los usuarios de PVD del año 2011, sobre los trastornos de salud y su implicación según el puesto. Los resultados obtenidos reflejan una mayor prevalencia de patología osteomuscular, seguida de ocular y por último mental. Una vez obtenidos los resultados, se informa al empresario de los mismos. El objetivo del estudio es conocer la patología ocasionada en los Usuarios de PVD, en relación derivada del puesto de trabajo e identificar los factores de riesgo y sus efectos sobre la salu

SOCIB Continuous Observations Of Ibiza Channel Using HF Radar

The Balearic Islands Coastal Observing and Forecasting System (SOCIB), is a multi-platform distributed and integrated system that provides streams of oceanographic data and modelling services to support operational oceanography in a European and International framework (in line with EuroGOOS). SOCIB is a facility of facilities that responds to a change of paradigm in the observation of the oceans and coasts that has evolved from single platform observing systems (the research vessels) to multi-platform and integrated observing systems. SOCIB is composed of three major subsystems (Tintoré et al., 2013): (1) an observing subsystem; (2) a forecasting and modelling subsystem and (3) a data management subsystem. The High Frequency (HF) Radar observing Facility is a key element of the observing system, and provides real-time two-dimensional surface velocity hourly observations in the Ibiza Channel. Dr. Arancha Lana, Dr. Joaquín Tintoré (Mediterranean Institute for Advance Studies) and Dr. Vicente Fernandez (freelance consultant) examine technology for the SOCIB Continuous Observations Of Ibiza Channel Using HF Radar (PDF Download Available). Available from: https://www.researchgate.net/publication/273909954_SOCIB_Continuous_Observations_Of_Ibiza_Channel_Using_HF_Radar [accessed Feb 9, 2016].Peer Reviewe

Surface current patterns in the Ibiza Channel with the use of High Frequency (HF) Radar system

Trabajo presentado en la EGU General Assemby 2014, celebrada del 27 de abril al 2 de mayo de 2014 en Viena (Austria)The Ibiza Channel located between the East Coast of the Iberian Peninsula, and the West Coast of Ibiza, at the Balearic Islands, is a well-known biodiversity hot spot. This area is relevant due to the interaction of water masses coming from the Atlantic Ocean – ascending through the Iberian Peninsula coast – with the older Atlantic waters descending from the Gulf of Lion. In 2012, the installation of Coastal HF Radar in the area provides valuable information for the study of the surface transport along the channel. The Coastal HF Radar operates since June 2012, and provides hourly surface current maps with a spatial resolution of approximately 3 km and a range reaching up to 70 km offshore. The instrument forms part of a monitoring multi-platform system, which is completed with satellite-derived data, gliders, modelling and fixed and lagrangian buoys. All HF Radar data are processed with standard quality control methods. Drifter velocity obtained from lagrangian buoys for two oceanographic campaigns, satellite-derived data and currentmeter data from a fixed buoy in the Ibiza Channel are used to validate the HF Radar data. All surface current data are used to perform a spectrum analysis in order to show the physical processes, at the main temporal periods. The contribution of the different temporal scales to the total Kinetic Energy has been analysed for the first time at different seasonal intervals. This served to evaluate the energetic importance of the different components of the surface currents. The inertial currents have a lower contribution to the total KE during winter, compared with the summer period. Besides, the spatial distribution of the inertial component to the total KE varies seasonally, and according to the bathymetry of the area. The low-pass (sub-inertial) filtered HF Radar currents show a predominant northern current during the summer months in the channel, and a mean southern current during the winter period. These results are discussed and related with the external forcing, and bathymetry distribution, according to coastal or open ocean dataPeer reviewe

Combined use of glider, radar and altimetry data to study a coastal current in the western Mediterranean Sea

Trabajo presentado en la EGU General Assemby 2014, celebrada del 27 de abril al 2 de mayo de 2014 en Viena (Austria)The Mediterranean Sea is characterized by a small Rossby radius of deformation, hence small structures and eddies. The Ibiza Channel, located in the Balearic Sea, is of particular importance since it controls the exchanges in the western Mediterranean Sea. In order to understand and describe the upper ocean dynamics, a multi-sensor/integrated approach was applied in the Ibiza Channel in the first days of August 2013 during the G-AltiKa mission. This approach combines: Sea-level anomaly (SLA) measurements from Saral-AltiKa track no. 16, which passed west of Ibiza island. 1-Hz and 40-Hz data were considered. Glider data obtained along the satellite track a few hours after its passage. The horizontal resolution ranges from 5 km offshore to about 1 km in the coastal area. HF radar hourly velocities on a 3 km-resolution grid that partially covers the study region (range up to 74 km offshore). Dynamic height (DH) was derived from the glider temperature and salinity profiles, while Absolute Dynamic Topography (ADT) was obtained by combining SLA and the new Mean Dynamic Topography (MDT) jointly produced by CLS and SOCIB. From DH and SLA, the cross-track velocities were derived using geostrophy relations. Different filters were applied on SLA data and different reference levels were tested for the DH computation. DH and ADT both displayed very weak variations, on the order of 2-3 cm, along the glider trajectory. The gliderand the altimetry-derived velocities exhibit the signal of a meander centered at 38.65◦N and a narrow coastal current flowing northward a few kilometers off Ibiza. These computed velocities are on the order of 20 cm/s, as confirmed by the HF radar. The time separation between the passage of the satellite and the glider can explain the discrepancies observed between the two platforms. Our results highlight the promising measurements offered by SARAL/AltiKa in the coastal band. In particular, the satellite was able is able to capture the northern edge of the meander which lied on a shallow bathymetry, less than 10 km from the coast. They also constitute the first experiment where satellite altimetry and glider measurements were obtained almost simultaneously on the same track, in a region covered by a HF radar. Such an approach allows us to process, validate and intercalibrate multi-platform datasets dedicated to coastal oceanPeer reviewe

Interpolation of SLA using Diva: Near-real time application during a multi-sensor experiment in the Ibiza Channel

Póster presentado en el OSTST (Ocean Surface Torpography Science Meeting) celebrado del 8 al 11 de octubre de 2013 en Boulder, Colorado (Estados Unidos) y organizado conjuntamente con el 7th Coastal Altimetry WorkshopThe spatial interpolation of Sea-Level Anomalies (SLA) along-track data to produce gridded map has numerous applications in oceanography, such model validation, data assimilation or eddy tracking. Optimal Interpolation (OI) is often the preferred method for this task, as it leads to the lowest expected error and provides an error field associated to the analyzed field. However, the numerical cost of the method (due to the inversion of covariance matrices) as well as the isotropic covariance function, generally employed in altimetry, may stand in the way of a systematic application to SLA data. The Data-Interpolating Variational Analysis (DIVA) is a gridding method based on the minimization of a cost function using a finite-element technique. The cost function penalizes the departure from observations, the smoothness or regularity of the gridded field and can also include physical constraints (advection, diffusion, ...). It has been shown that DIVA and OI are equivalent (provided some assumptions on the covariances are made), the main difference is that in DIVA, the covariance function is not explicitly formulated. The technique has been previously applied for the creation of regional hydrographic climatologies, which required the processing of a large number of data points. In this work we present a implementation of Diva for generating high-resolution daily maps of SLA, ADT and geostrophic currents in the Mediterranean Sea. The procedure for the productions of the gridded products is as follow: 1. The download and formatting of AVISO NetCDF data files. This step is performed with bash scripts with the help of NCO toolbox. 2. The interpolation of SLA measurements using the DIVA tool and the generation of NetCDF files. 3. The computation of geostrophic velocity using the new SOCIB-CLS Mean Dynamic Topography (MDT). 4. The preparation of graphics for the region of interest. This step is performed with a script in Python using the Matplotlib plotting library. The generated maps were used in the frame of G-ALTIKA (see poster by Pascual et al.) experiments carried out in the southwest of Ibiza island in August 2013. The results for this region show a good agreement with AVISO near-real time products for the Mediterranean Sea, while some differences are observed in the representation of eddies and meanders. HF Radar data partially covering G-ALTIKA domain as well as drifter are used for further validation and comparisonPeer Reviewe

Interactions between angler movement behaviour and an invasive seaweed with ecosystem engineering properties in a marine recreational fishery

The establishment of non-native, habitat-forming seaweeds into new areas may trigger changes in ecosystem functioning, including the spatial redistribution of native biodiversity. These changes can in turn affect socio-economic systems. We studied the question whether the spatial behaviour of marine anglers is altered by the presence of a non-native seaweed using a novel image-based method to measure fisher movements. A Hidden Markov Model (HMM) was applied to high resolution tracking data of marine recreational boat anglers exploiting a coastal fishery half covered by a recently introduced tropical seaweed, Halimeda incrassata. We then examined if the presence of the non-native seaweed affected the transition probability between two key behavioural states of the anglers: searching and fishing. The analysis revealed a significant effect of the seaweed presence at site-level on angler movement behaviour, but in the opposite direction that we predicted: the presence of the non-native seaweed led a decrease in the use of invaded patches although these patches are known to host an increased fish abundance. Invaded sites thus were attractive to the target fishes, but not for anglers, leading to repulsion. We conclude that, at the patch level non-native habitat forming seaweeds can exert substantial impacts on fisher behaviour in marine recreational fisheries. We discuss future studies needed to shed light to the social-economic impact of H. incrassata for local temperate recreational fisheries.JA was supported by a Ramon y Cajal Grant (grant no. RYC2018-024488-I) and the intramural research project JSATS (grant no. PIE 202030E002) funded by the Spanish Ministry of Science and Innovation, and the Spanish National Research Council. This study has been developed within the research project AutoNatura2000dos funded by the Ministerio para la Transición Ecológica - Fundación Biodiversidad through the program PLEAMAR and the Fondo Europeo Marítimo Pesquero (FEMP). We thank Antoni Grau (Govern de les Illes Balears, Direcció General de Pesca) for supporting and authorizing this study and all researcher involved in the field work. RA received funding through the European Union (European Maritime and Fisheries Fund) and the State of Mecklenburg-Vorpommern (Germany) (Grant MV-I.18-LM-004, B 730117000069), and the German Federal Ministry of Education and Research (Grants 01LC1826E and 033W046A)