Longline-caught blue shark (Prionace glauca): factors affecting the numbers available for live release*

The blue shark (Prionace glauca) is an oceanic species that occurs in temperate and tropical waters around the globe (Robins and Ray, 1986). This species is a major bycatch of pelagic longline fleets that operate to supply the world’s growing demand for tunas and swordfish (Xiphias gladius) (Stevens, 1992; Bailey et al., 1996; Francis, 1998; Francis et al., 2001; Macias and de la Serna, 2002); numerically, the blue shark is the top nontarget species captured by the U.S. longline pelagic Atlantic fleet (Beerkircher et al

¿Cómo enseñar la Web Semántica?

Los objetivos, tecnologías y problemas relacionados con la Web Semántica están claramente establecidos a nivel de investigación. Sin embargo, la gran envergadura del proyecto hace difícil su divulgación a nivel docente. Los profesores universitarios encuentran muchas dificultades a la hora de explicar las materias relacionadas con la Web Semántica. Existe un acuerdo en que la enseñanza de estos contenidos debe tener una fuerte componente práctica y de experimentación. Sin embargo, aunque cada tema puede ser explicado de forma independiente, existe una dificultad inherente a la elaboración de trabajos autocontenidos, pero relacionados entre sí, con los que poner en práctica todos los conceptos y comprender sus dificultades y dependencias. En este artículo se presenta la experiencia con una práctica en el dominio del marcado y recuperación de imágenes.Este trabajo ha sido parcialmente financiado por la Dirección General de Universidades e Investigación de la Consejería de Educación de la Comunidad de Madrid y por la Universidad Complutense de Madrid (Grupo de investigación consolidado 910494), y por el Ministerio de Ciencia y Tecnología (TIN2006-15140-C03-02 y TIN2006-15202-C03-03)

Radar remote sensing estimates of waves and wave forcing at a tidal inlet

Author Posting. © American Meteorological Society, 2015. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Atmospheric and Oceanic Technology 32 (2015): 842–854, doi:10.1175/JTECH-D-14-00215.1.The time and space variability of wave transformation through a tidal inlet is investigated with radar remote sensing. The frequency of wave breaking and the net wave breaking dissipation at high spatial resolution is estimated using image sequences acquired with a land-based X-band marine radar. Using the radar intensity data, transformed to normalized radar cross section σ0, the temporal and spatial distributions of wave breaking are identified using a threshold developed via the data probability density function. In addition, the inlet bathymetry is determined via depth inversion of the radar-derived frequencies and wavenumbers of the surface waves using a preexisting algorithm (cBathy). Wave height transformation is calculated through the 1D cross-shore energy flux equation incorporating the radar-estimated breaking distribution and bathymetry. The accuracy of the methodology is tested by comparison with in situ wave height observations over a 9-day period, obtaining correlation values R = 0.68 to 0.96, and root-mean-square errors from 0.05 to 0.19 m. Predicted wave forcing, computed as the along-inlet gradient of the cross-shore radiation stress was onshore during high-wave conditions, in good agreement (R = 0.95) with observations.These data were collected as part of a joint field program, Data Assimilation and Remote Sensing for Littoral Applications (DARLA) and Rivers and Inlets (RIVET-1), both funded by the Office of Naval Research. The authors were funded through the Office of Naval Research Grant N00014-10-1-0932 and the Office of the Assistant Secretary of Defense for Research and Engineering.2015-10-0

A near-infrared view of Nearby Galaxies: The Case of NGC 6300

We present a near-infrared study of the Seyfert 2 galaxy NGC 6300, based on subarcsecond images and long slit spectroscopy obtained with Flamingos-2 at Gemini South. We have found that the peak of the nuclear continuum emission in the K s band and the surrounding nuclear disk are 25 pc off-center with respect to the center of symmetry of the larger scale circumnuclear disk, suggesting that this black hole is still not fixed in the galaxy potential well. The molecular gas radial velocity curve yields a central black hole upper mass estimation of . The Paβ emission line has a strongly asymmetric profile with a blueshifted broad component that we associate with a nuclear ionized gas outflow. We have found in the K s -band spectra that the slope of the continuum becomes steeper with increasing radii, which can be explained as the presence of large amounts of hot dust not only in the nucleus but also in the circumnuclear region up to r = 27 pc. In fact, the nuclear red excess obtained after subtracting the stellar contribution resembles to that of a blackbody with temperatures around 1200 K. This evidence supports the idea that absorbing material located around the nucleus, but not close enough to be the torus of the unified model, could be responsible for at least part of the nuclear obscuration in this Seyfert 2 nucleus.Fil: Gaspar, Gaia. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Diaz, Ruben Joaquin. Observatorio Astronomico de la Universidad Nacional de Cordoba; Argentina. Gemini Observatory; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Mast, Damian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Observatorio Astronomico de la Universidad Nacional de Cordoba; ArgentinaFil: D'Ambra, A.. Observatorio Astronomico de la Universidad Nacional de Cordoba; ArgentinaFil: Agüero, Maria Paz. Observatorio Astronomico de la Universidad Nacional de Cordoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gunthardt, Guillermo Ivan. Observatorio Astronomico de la Universidad Nacional de Cordoba; Argentin

Uso de competiciones y sistemas de clasificación como metodología de evaluación de una asignatura

En este artículo describimos nuestra experiencia en el uso de una metodología de enseñanza activa y participativa orientada al aprendizaje de técnicas de Inteligencia Artificial entre los estudiantes de Informática. En concreto describimos una aproximación basada en competiciones para evaluar las prácticas de los alumnos y un conjunto de herramientas desarrollado para el apoyo de esta metodología. Esta experiencia nos muestra que las competiciones como parte del método de evaluación incrementan la motivación de los alumnos y proporcionan un mecanismo para que el alumno demuestre sus habilidades, sus proyectos, comparta sus intereses y pueda compararse con otros. Así mismo, presentamos los resultados obtenidos en las encuestas realizadas a los alumnos sobre el uso de las competiciones, así como un experimento que analiza la correlación entre las notas reales obtenidas por los alumnos en las prácticas y la posición alcanzada en la competición.Financiado por el Ministerio de Ciencia e Innovación TIN2009-13692-C03-03 y la Universidad Complutense de Madrid PIMCD-179

Uso de competiciones y sistemas de clasificación como metodología de evaluación de una asignatura

En este artículo describimos nuestra experiencia en el uso de una metodología de enseñanza activa y participativa orientada al aprendizaje de técnicas de Inteligencia Artificial entre los estudiantes de Informática. En concreto describimos una aproximación basada en competiciones para evaluar las prácticas de los alumnos y un conjunto de herramientas desarrollado para el apoyo de esta metodología. Esta experiencia nos muestra que las competiciones como parte del método de evaluación incrementan la motivación de los alumnos y proporcionan un mecanismo para que el alumno demuestre sus habilidades, sus proyectos, comparta sus intereses y pueda compararse con otros. Así mismo, presentamos los resultados obtenidos en las encuestas realizadas a los alumnos sobre el uso de las competiciones, así como un experimento que analiza la correlación entre las notas reales obtenidas por los alumnos en las prácticas y la posición alcanzada en la competición.Financiado por el Ministerio de Ciencia e Innovación TIN2009-13692-C03-03 y la Universidad Complutense de Madrid PIMCD-179

Circle Hooks in Commercial, Recreational, and Artisanal Fisheries: Research Status and Needs for Improved Conservation and Management

The intent of convening the International Symposium on Circle Hooks in Research, Management, and Conservation was to yield a contemporary, science-based assessment of the management and conservation utility of circle hooks in commercial, recreational, and artisanal fisheries around the globe. The symposium objective was to provide a forum for individuals, organizations, and agencies to share relevant research results and perspectives. Based on the presentations, an examination of the literature, and the collective experience and knowledge of the authors, we provide a brief overview of the current status of circle hook research along with a list of research needs, with a particular focus on science that has the potential to inform managers and stakeholders. Progress was made on the definition of a “true circle hook.” There was strong recognition that circle hooks represent just one of the tools available to managers for reducing bycatch and release mortality. Also defined was the need for an integrative approach that considers strategies that complement the use of circle hooks. Some of the research needs identified include a greater emphasis on human dimension studies to identify those factors that may impede adoption of circle hook technology by stakeholders and comparative studies of circle hook performance relative to mouth morphology, dentition, and feeding behavior. While the literature on effective use of circle hooks is growing, there remains a number of unanswered questions that will require study before circle hooks are more widely adopted for conservation and management of aquatic living resources

Benthic Habitat Mapping in the Tortugas Region, Florida

Concern about declining trends in coral reef habitats and reef fish stocks in the Florida Keys contributed to the implementation of a network of no-take marine protected areas in 1997. In support of the efforts of the Dry Tortugas National Park and Florida Keys National Marine Sanctuary to implement additional no-take areas in the Tortugas region in 2001, we expanded the scale of our fisheries independent monitoring program for coral reef fishes in the region. To provide a foundation for the habitat-based, stratified random sampling design of the program, we created a digital benthic habitat map of coral reef and hard-bottom habitats in a geographic information system by synthesizing data from bathymetric surveys, side-scan sonar imagery, aerial photogrammetry, existing habitat maps, and in situ visual surveys. Existing habitat maps prior to 1999 were limited to shallow-water (\u3c 20 m depth) soft-sediment, coral reef, and hard-bottom habitats within Dry Tortugas National Park and did not include deeper areas such as the Tortugas Bank, now partially contained within no-take marine protected area boundaries. From diver observations made during the 1999 survey, we developed a classification scheme based on habitat relief and patchiness to describe nine hard-bottom and coral reef habitats encountered from 1-33 m depth. We provide estimates of area by habitat type for no-take marine protected areas in the Tortugas region. Updated information on the spatial distribution and characteristics of benthic habitats will be used to guide future monitoring, assessment, and management activities in the region. Significant data gaps still exist for the western area of the Florida Keys National Marine Sanctuary and are a priority for future research