191 research outputs found
Connectivity Patterns for Direct Developing Invertebrates in Fragmented Marine Habitats: Fish Farms Fouling as Source Population in the Establishment and Maintenance of Local Metapopulations
Artificial structures can be considered as high spatially structured habitats in the marine pelagic system, where patch connectivity would be strongly dependent on the exchange of larvae or dispersing individuals. Fish-farms located offshore may alter ecological connectivity, modifying trophic resources, and species dispersal among patches. High population densities of invertebrates can be found associated with fish-farm fouling communities, which can act as a seed source, contributing to the patterns of connectivity through individuals exchange between subpopulations or with sink populations. A field experiment was performed to analyse the role of fish-farms in the colonisation of new uninhabited habitats (floating experimental units) located at different positions relative to the fish farm and the main current, containing artificial habitats with and without feed pellets similar to those used in the fish farm. Amphipods were used as example of direct developing invertebrates for studying dispersing individuals from the fish farm to the new habitats. The richest and most abundant populations in this study were found close to and downstream of the fish farm, surpassing 1,000 amphipods at their maximum. Moreover, some floating habitats located more than 2 km from the fish farm were colonised in only 15 days. Thus, the role of fish farms has been shown to extend beyond a ‘stepping-stones’ effect in species dispersal, and have an additional effect on ecological connectivity by increasing population sizes and acting as population source. Our study aims to provide recommendations for coastal zone management in order to predict potential spread from fish farms to other platforms in the future and promote solutions related to interactions and consequences of connectivity within and between marine facilities
Sistema para la adquisición de señales electrocardiográficas usando Matlab®.
Este trabajo presenta un sistema para la obtención de nueve derivaciones de un electrocardiograma usando la herramienta para adquisición de datos de Simulink. El sistema consta de una etapa de instrumentación conectada a un cable para electrocadiograma que toma los potenciales de nueve electrodos superficiales, con ellos se adquieren tres derivaciones bipolares y seis derivaciones precordiales. Las nueve derivaciones fueron filtradas usando dos filtros análogos Butterworth de cuarto orden, pasaaltos y pasabajos, en cascada y luego fueron adquiridas a través de una tarjeta de adquisición de datos NI USB-6215. Finalmente, las derivaciones fueron visualizadas y almacenas en Matalb®
Sistema para la adquisición de señales electrocardiográficas usando Matlab®.
Este trabajo presenta un sistema para la obtención de nueve derivaciones de un electrocardiograma usando la herramienta para adquisición de datos de Simulink. El sistema consta de una etapa de instrumentación conectada a un cable para electrocadiograma que toma los potenciales de nueve electrodos superficiales, con ellos se adquieren tres derivaciones bipolares y seis derivaciones precordiales. Las nueve derivaciones fueron filtradas usando dos filtros análogos Butterworth de cuarto orden, pasaaltos y pasabajos, en cascada y luego fueron adquiridas a través de una tarjeta de adquisición de datos NI USB-6215. Finalmente, las derivaciones fueron visualizadas y almacenas en Matalb®
Depositional depth of laminated carbonate deposits: Insights from the lower Cretaceous Valdeprado formation (Cameros Basin, Northern Spain)
The Lower Cretaceous (Berriasian) Valdeprado Formation (Cameros Basin, northern Spain) contains more than 900 m of laminated carbonates and pseudomorphs after sulfates. Traditionally, many sedimentary packages of different ages and lithologies have been interpreted as deep-water deposits based essentially on the abundance of laminations and the absence of subaerial exposure features. In contrast, the Valdeprado Formation provides an example of a shallow-water deposit dominated by laminations with scarce evidence of subaerial exposure, and gives criteria to solve the challenge of distinguishing
shallow-water and deep-water, ancient laminated deposits.
The two most abundant facies all along the Valdeprado Formation are: a) parallel-laminated limestone, formed by
alternating carbonate mudstone and calcite and quartz pseudomorphs after displacive gypsum, and b) graded-laminated limestone, consisting of quartz, mica, ostracodes, and pseudomorphs after detrital gypsum grains at the base, which changes gradually upwards to carbonate mudstone. Parallel-laminated limestone and graded-laminated limestone could have been deposited in either deep or shallow environments as a result of salinity fluctuations driven by alternation of flooding and
evaporation and by sediment resuspension processes, respectively. Subaerial exposure features, such as desiccation mudcracks, are scarce in most of the succession, except in a few meter-scale stratigraphic intervals where they are very abundant. Interestingly, in these intervals desiccation cracks are present at the tops of several successive laminae (up to 25 mudcracked
laminae per meter of deposit), indicating that, at least during those periods of time, deposition occurred in shallow water bodies that were desiccated frequently. In the upper part of the stratigraphic section, parallel-laminated and graded-laminated limestones are associated with current-ripple and wave-ripple cross-laminated arenites, and ostracode mudstone to wackestone with centimeter-size pseudomorphs after lenticular gypsum, and abundant desiccation mudcracks and tepees, which also suggest
sedimentation in shallow-water environments. Moreover, the laminated carbonates display continuous, parallel layering, and the same facies along the 40-km-long outcropping area. These deposits are directly interbedded with, and pass laterally to, siliciclastic sandy–muddy flat deposits in the western area of the basin, without clinoforms, slump structures, or slide masses in between. All of these features suggest deposition in shallow, perennial carbonate–sulfate water bodies and their peripheral mudflats, developed in a flat-bottomed basin with no marked gradients
Applied medical informatics for neuroanatomy training
[EN]In recent years, the efforts to apply developments in
medical informatics within training contexts have increased. The
objective of this paper is to illustrate the benefits associated to the
use of three-dimensional visualization digital systems, in a
neuroanatomical training context, and evaluate the satisfaction
level and perceived usefulness of these tools by students. The three dimensional models generated allowed the anatomical interactive
study of brain structures and their spatial relationships in a
complete, realistic and visually appealing manner for students,
regardless of previous visuo-spatial skills
First biological data, associated fauna, and microclimate preferences of the enigmatic cave-dwelling beetle Dalyat mirabilis Mateu, 2002 (Coleoptera, Carabidae)
Dalyat mirabilis is an extraordinary troglobite carabid described in 2002 from the cave Simarrón II in the southeast of the Iberian Peninsula (Spain). A new subfamily Dalyatinae was erected to accommodate this species with remarkable morphological characters and adaptations to live underground. In addition to the former original descriptions, there is only one more study and it aimed to elucidate its evolutionary history. Its closest living relative belongs to the genus Promecognathus in North America and both groups seem to have diverged sometime in the late Jurassic to early Cretaceous. In this work, the phenology of D. mirabilis, its associated invertebrate fauna and the environmental conditions of the cave Simarrón II were studied for a full year cycle. This carabid is not evenly distributed in the cave, in time or space. It is most abundant during the winter months, wet season, and it disappears from the top layer of the substrate in the summer. A positive correlation was found between the number of carabids captured per trap and the distance to the entrance of the cave; most specimens were captured in traps farthest from the entrance and located in the chamber known as Vias Salas Negras. Furthermore, several spatially-resolved analyses integrating relative humidity, temperature, and the number of captures per trap showed that D. mirabilis prefers Vias Salas Negras for having a higher and more stable relative humidity than other chambers in the cave. Larvae were never captured, regardless of intense efforts to collect them for years. Finally, 30 other invertebrate species belonging to 12 different Orders were captured in the cave and are listed here, 25.8% are troglobites, 29.0% troglophiles and 45.2% troglexenes. The data from this study was used for an initiative to protect this cave and its remarkable fauna. Some of the measures taken by the Administration include the control of human visits to the cave, the installation of a perimetral fence surrounding the entrance, and the installation of an informative panel at the exterior of the cave describing the endemic entomological fauna it contains
Calcareous algae (dasycladales and charophytes), essential for the sedimentological interpretation of ancient coastal-lakes systems. The Barremian-Aptian Leza Fm., Cameros Basin, N Spain
Depto. de Geodinámica, EstratigrafÃa y PaleontologÃaFac. de Ciencias GeológicasTRUEpu
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