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Póster.-- Iberian Symposium on Modeling and Assessment of Fishery Resources, 19-22 October, Vigo, Spain, The main control measures used in EU fisheries are the use of logbooks, monitoring of vessel geographic positions and the inspections of the vessels at sea (patrol vessel surveillance) and at the ports (inspection of the landings). Many studies indicate that this traditional control measures are not effective within the current Landing Obligation rules. The Remote Electronic Monitoring (REM) is currently considered as one of the best future alternatives for the control of fishing activity. In fact, many fleets have already incorporated this technology into their activity to respond to the requirements of regional fishing organizations and control authorities in many countries of the world. The aim of this work was to test the implementation of innovative technologies based on artificial vision devices for catch composition determination and data management technologies installed on board. A study case including onboard observer trials and an automatic device was carried out to characterize discards and record unwanted species occurrence in commercial vessels. The “iObserver system” was implemented to improve the quality and availability of data and consequently to deepen knowledge on the status of the fisheries resources. This technology is aimed to be able to identify and quantify the catch (targeted and discarded) without interfering with the activity of fishermen. Once the data (species and biomass estimation) is acquired by iObserver, information is pre-processed and transmitted to land (to management servers). This system will allow real-time decision making for the fishing activity in order to eventually perform a more selective fishing. Automatic estimates of discards by species allow to take real-time decisions, avoid areas/times with high discards rates and potentially to comply with landing obligation

World Fisheries Congress 2021, 20-24 September, Adelaide (Australia), Sustainability is a basic premise for the economic and social future of fisheries and the main objective of fishing policies, such as the Common Fisheries Policy of the European Union. An immense challenge faced by sustainable fisheries management and policies is that of finding cost-effective monitoring methods. Several remote electronic monitoring devices (REM) systems are available to that purpose; however, many of them exhibit a number of drawbacks that prevent its generalization among fleets (e.g. off-line evaluation of catches by the so-called dry observers in land, crew interferences and distrust, etc.). To overcome these drawbacks, robust and reliable innovative technologies for registering captures are required. In this regard, we have developed the iObserver, an electronic device for automatic identification and quantification of the whole catch on board fishing vessels. The iObserver is installed in the fishing park, over the conveyor belt, just before the fishing separation zone. The system takes images of everything that crosses this conveyor belt during the separation process. The recognition software automatically analyzes every image, identifies all the individuals, estimates their length and generates a report containing the results. The Deep Learning algorithms for species recognition algorithms included in the iObserver use Convolutional Neural Networks. Two models were created with transfer learning and data augmentation techniques: an instance segmentation model for specimen detection and classification and a regression model for fish length estimation. To train and test both models, a set of about 6,000 images were labeled with mask, species and length of each individual for a selection of 14 of the most relevant species for the local fisheries. Preliminary results were promising: precision and recall of 98% and 95% respectively for species recognition and 3.2% mean absolute percentage error for length estimation in the test data set. Species identification and quantification results are combined with data supplied by the vessel instrumentation, such as position, course, velocity. Finally, these georeferenced total catch data (a small CSV file) is sent, in real time, to an onshore center for further displaying and analysis enabling their use, either by ship-owners or policy makers, for efficient fishing activity management purposes

Poster.-- XXII Foro dos Recursos Mariños e da Acuicultura das Rías Galegas, O Grove, 10-11 de outubro de 2019

We investigate how a spherically symmetric scalar field can modify the Schwarzschild vacuum solution when there is no exchange of energy-momentum between the scalar field and the central source of the Schwarzschild metric. This system is described by means of the gravitational decoupling by Minimal Geometric Deformation (MGD-decoupling), which allows us to show that, under the MGD paradigm, the Schwarzschild solution is modified in such a way that a naked singularity appears., Comment: 16 pages, 2 figures. arXiv admin note: text overlap with arXiv:1804.03468

This paper presents a detailed discussion of the issue of supergravity perturbations around the flat five dimensional superspace required for manifest superspace formulations of the supergravity side of the AdS_{5}/CFT_{4} Correspondence., Comment: The representation preserving constraints and their consequences are considered; Symmetries and semi-prepotentials sections corrected and improved; typos corrected

To study the rate of infection by Epstein Barr virus (EBV) in Santiago, Chile, the prevalence of antibody to the viral capsid antigen (VCA-IgG) was determined in a group of 663 healthy individuals grouped by age and socioeconomic level (SEL). In addition, several risk factors for infection were studied. VCA-IgG was determined by ELISA. The total prevalence was 76.7%. When grouped by age and SEL, 50% of the children from low and medium SEL had been already infected by the age two, compared to 5.9% in the high SEL (p0.01). However, by age twenty, 90% of the total sample had already specific antibodies to EBV. Age and number of household members were positively associated with the infection. High socioeconomic level represented a delay factor in the acquisition of the virus, (p0.01). These results show that EBV infection is frequent in Santiago, occurring early in childhood among medium and low SEL. Hence, the classical infectious mononucleosis should be recognized more frequently among adolescents and young adults belonging to high SEL, while the clinical spectrum of associated manifestations different from the typical mononucleosis syndrome should be investigated among those exposed in early age.

Black holes with hair represented by generic fields surrounding the central source of the vacuum Schwarzschild metric are examined under the minimal set of requirements consisting of i) the existence of a well defined event horizon and ii) the strong or dominant energy condition for the hair outside the horizon. We develop our analysis by means of the gravitational decoupling approach. We find that trivial deformations of the seed Schwarzschild vacuum preserve the energy conditions and provide a new mechanism to evade the no-hair theorem based on a primary hair associated with the charge generating these transformations. Under the above conditions i) and ii), this charge consistently increases the entropy from the minimum value given by the Schwarzschild geometry. As a direct application, we find a non-trivial extension of the Reissner-Nordstrom black hole showing a surprisingly simple horizon. Finally, the non-linear electrodynamics generating this new solution is fully specified., Comment: 11 pages, 4 figures

We employ the gravitational decoupling approach for static and spherically symmetric systems to develop a simple and powerful method in order to a) continuously isotropize any anisotropic solution of the Einstein field equations, and b) generate new solutions for self-gravitating distributions with the same or vanishing complexity factor. A few working examples are given for illustrative purposes., 8 pages, 4 figures

We review the basic elements of the Minimal Geometric Deformation approach in details. This method has been successfully used to generate brane-world configurations from general relativistic perfect fluid solutions., Brief review; minor corrections; references added

We examined whether variations in photosynthetic capacity are linked to variations in the environment and/or associated leaf traits for tropical moist forests (TMFs) in the Andes/western Amazon regions of Peru. We compared photosynthetic capacity (maximal rate of carboxylation of Rubisco (Vcmax), and the maximum rate of electron transport (Jmax)), leaf mass, nitrogen (N) and phosphorus (P) per unit leaf area (Ma, Na and Pa, respectively), and chlorophyll from 210 species at 18 field sites along a 3300-m elevation gradient. Western blots were used to quantify the abundance of the CO2-fixing enzyme Rubisco. Area- and N-based rates of photosynthetic capacity at 25°C were higher in upland than lowland TMFs, underpinned by greater investment of N in photosynthesis in high-elevation trees. Soil [P] and leaf Pa were key explanatory factors for models of area-based Vcmax and Jmax but did not account for variations in photosynthetic N-use efficiency. At any given Na and Pa, the fraction of N allocated to photosynthesis was higher in upland than lowland species. For a small subset of lowland TMF trees examined, a substantial fraction of Rubisco was inactive. These results highlight the importance of soil- and leaf-P in defining the photosynthetic capacity of TMFs, with variations in N allocation and Rubisco activation state further influencing photosynthetic rates and N-use efficiency of these critically important forests. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust

We investigate how a spherically symmetric fluid modifies the Schwarzschild vacuum solution when there is no exchange of energy-momentum between the fluid and the central source of the Schwarzschild metric. This system is described by means of the gravitational decoupling realised via the minimal geometric deformation approach, which allows us to prove that the fluid must be anisotropic. Several cases are then explicitly shown, New section with a regular hairy black hole solution; references added

We conjecture that any modification of general relativity can be studied by the minimal geometric deformation approach provided that such modification can be represented by a traceless energy-momentum tensor., Comment: Based on the contributed lecture given at the IF-YITP Cosmo International Symposium. Phitsanulok, Thailand, August 3-5, 2016

The minimal geometric deformation approach was introduced in order to study the exterior space-time around spherically symmetric self-gravitating systems, like stars or similar astrophysical objects as well, in the Randall-Sundrum brane-world framework. A consistent extension of this approach is developed here, which contains modifications of both the time component and the radial component of a spherically symmetric metric. A modified Schwarzschild geometry is obtained as an example of its simplest application, and a new solution potentially useful to describe stars in the brane-world is also presented., Comment: Improved version with new solutions. 11 pages, 4 figures. To be published in CQG