1,285 research outputs found

    Petrología de la granodiorita de Peña Prieta (León, Santander, Palencia)

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    The granite autcrops of Peña Prieta situated on the harder of the Provinces of León, Santander and Palencia, are 1)etrologically studied in this work. This rock is a postectonic granodiorite with biotite and hornblende. The intense microtectonization in the mica is to he particularly noted in contrast with the remaining mineral components. The paragenetic relationship of the amphibol are also discussed

    Water maser detections in southern candidates to post-AGB stars and Planetary Nebulae

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    We intended to study the incidence and characteristics of water masers in the envelopes of stars in the post-AGB and PN evolutionary stages. We have used the 64-m antenna in Parkes (Australia) to search for water maser emission at 22 GHz, towards a sample of 74 sources with IRAS colours characteristic of post-AGB stars and PNe, at declination <32deg< -32 \deg. In our sample, 39% of the sources are PNe or PNe candidates, and 50% are post-AGB stars or post-AGB candidates. We have detected four new water masers, all of them in optically obscured sources: three in PNe candidates (IRAS 12405-6219, IRAS 15103-5754, and IRAS 16333-4807); and one in a post-AGB candidate (IRAS 13500-6106). The PN candidate IRAS 15103-5754 has water fountain characteristics, and it could be the first PN of this class found. We confirm the tendency suggested in Paper I that the presence of water masers in the post-AGB phase is favoured in obscured sources with massive envelopes. We propose an evolutionary scenario for water masers in the post-AGB and PNe stages, in which ``water fountain'' masers could develop during post-AGB and early PN stages. Later PNe would show lower velocity maser emission, both along jets and close to the central objects, with only the central masers remaining in more evolved PNe.Comment: 11 pages, 5 figures. Accepted by Astronomy and Astrophysic

    gOntt, a Tool for Scheduling and Executing Ontology Development Projects

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    Nowadays the ontology engineering field does not have any method that guides ontology practitioners when planning and scheduling their ontology development projects. The field also lacks the tools that help ontology practitioners to plan, schedule, and execute such projects. This paper tries to contribute to the solution of these problems by proposing the identification of two ontology life cycle models, the definition of the methodological basis for scheduling ontology projects, and a tool called gOntt that (1) supports the scheduling of ontology developments and (2) helps to execute such development projects

    Nebular emission lines in IRAS 17347-3139

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    We report the detection of nebular emission lines in the optical and mid-infrared spectra of IRAS 17347-3139, a heavily obscured OH/IR star which may be rapidly evolving from the AGB to the PN stage. The presence of emission lines is interpreted as a clear indication that the ionization of its circumstellar envelope has already started. This source belongs to the rare class of objects known as `OHPNe' displaying both OH maser and radio continuum emission. However, unlike the rest of stars in this class, prominent C-rich dust features are detected in its mid-infrared spectrum, which makes the analysis of this star particularly interesting.Comment: 2 pages, 2 figures, Proc. IAU Symp. 234, Planetary Nebulae in Our Galaxy and Beyond (3-7 Apr 2006), eds. M.J. Barlow & R.H. Mendez (Cambridge Univ. Press

    Influence of anthropometry and body composition in climbing ability

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    INTRODUCTION: Climbing has become a popular, competitive and recreational sport. It requires, principally, skilled technique and high muscle strength. Therefore, it has been necessary to implement formal studies about the training of this discipline. Investigations have been performed some studies to demonstrate that the improvement of climbing can be explained with anthropometric and physiological variables. PURPOSE: The purpose of this study was evaluate the main variables that affect the performance of the climbing, namely, anthropometry, body composition and climbing level. METHODS: Eighteen climbers, ranged 22 - 40 years old and V2-V7 of climbing ability (according Hueco Tanks scale), were volunteered to participate. Measurements of anthropometric characteristics and body composition including height, arm spam, forearm maximum, midstylion-dactilion, lean arm mass, body mass index (BMI), skeletal muscle mass, body fat mass, visceral fat, were performed. All variables were evaluated by using a combination of a principal component analysis (PCA) with a cluster analysis. RESULTS: When the analysis was performed in both anthropometry (skeletal muscle mass, lean arm mass and forearm maximum) and body composition (BMI, body fat mass and visceral fat) groups of variables, the results showed an 86% of the variance. The anthropometry variables showed correlation with 60% of the total variance. Concretely, the higher climbing level athletes (V5-V7) showed a higher lean body mass and arm muscle mass than the lower climbing levels athletes (V0-V4). On the other hand, the last group showed higher body fat mass and visceral fat mass with respect to the V5-V7 climbing athletes. CONCLUSION: The data of the present study showed a clear tendency on the variables, both body composition and anthropometry, in terms of the climbing level. However, these results are not completely conclusive. We suggest necessary to improve the performance of the measurements in future studies

    A spectroscopic atlas of post-AGB stars and planetary nebulae selected from the IRAS Point Source Catalogue

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    Aims: We study the optical spectral properties of a sample of stars showing far infrared colours similar to those of well-known planetary nebulae. The large majority of them were unidentified sources or poorly known in the literature at the time when this spectroscopic survey started, some 15 years ago. Methods: We present low-resolution optical spectroscopy, finding charts and improved astrometric coordinates of a sample of 253 IRAS sources. Results: We have identified 103 sources as post-AGB stars, 21 as ``transition sources'', and 36 as planetary nebulae, some of them strongly reddened. Among the rest of sources in the sample, we were also able to identify 38 young stellar objects, 5 peculiar stars, and 2 Seyfert galaxies. Up to 49 sources in our spectroscopic sample do not show any optical counterpart, and most of them are suggested to be heavily obscured post-AGB stars, rapidly evolving on their way to becoming planetary nebulae. Conclusions: An analysis of the galactic distribution of the sources identified as evolved stars in the sample is presented together with a study of the distribution of these stars in the IRAS two-colour diagram. Finally, the spectral type distribution and other properties of the sources identified as post-AGB in this spectroscopic survey are discussed in the framework of stellar evolution.Comment: 69 pages, 413 figures. Accepted by Astronomy and Astrophysic

    GLMP 621: A BINARY PLANETARY NEBULA

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    RESUMEN El estudio observacional de GLMP 621 ha permitido su identificación como una nebulosa planetaria de reciente formación. Con el objeto de estudiar el sistema en detalle hemos obtenido imágenes de esta fuente, que se reportan en este trabajo, utilizando el telescopio NOT de 2.5 m con la cámara ALFOSC conjuntamente con un juego de filtros de banda angosta (ver Riera et al. 2003). También se obtuvieron observaciones espectroscópicas de alta dispersión. La complicada geometría y cinemática observada en GLMP 621 se asemeja a la de otras proto-nebulosas planetarias con una estructura multipolar dentro de un halo esférico. ABSTRACT The observational study of GLMP 621 have identified it as a newly-formed planetary nebula. In order to observe the system in more detail we have obtained images of this source, reported here, using the 2.5 m NOT Telescope with the ALFOSC camera together with a set of narrow band filters (see Key Words: PLANETARY NEBULAE -ISM: JETS AND OUTFLOWS GLMP 621 (IRAS 17395-0841) was first identified as a possible newly-formed planetary nebula on the basis of its IRAS colours (García-Lario 1992). A few years ago it was confirmed as such through spectroscopic observations where nebular emission lines corresponding to a proto-typical low excitation planetary nebula were detected overimposed on a strong and red continuum corresponding to a star of intermediate spectral type The observational study of this planetary nebula was complemented with CCD images taken at various broad and narrow band filters which showed the source is actually a binary system, in which one of the components is the central star of the PN. In order to observe the system in more detail we have obtained images of this source using the 2.5 m NOT Telescope (La Palma, Spain) with the ALFOSC camera together with a set of narrow band filters (see • (alon

    Análisis paleoambiental de los depósitos aluviales de la sección de Cenicero a partir de las asociaciones de ostrácodos (Mioceno inferior, NO de la Cuenca del Ebro)

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    In this work we perform for the first time a palaeoenvironmental and biostratigraphic analysis of the lower Miocene alluvial deposits of the Cenicero section (NW sector of the Ebro Basin; N Iberian Peninsula), based on the ostracod and micromammal assemblages. One of the main characteristics of this section is the unusual abundance on non-reworked ostracods present in the studied samples compared to other European sequences of similar age and sedimentary environment. This fact has allowed us to develop precise palaeoenvironmental reconstructions. The variations of the identified ostracod assemblages, defined by species such as Cyclocypris laevis, Ilyocypris bradyi, Ilyocypris gibba, Limnocythere sp. or Pseudocandona parallela, record the development of small, ephem-eral and shallow ponds in a distal alluvial and/or floodplain environment. Towards the upper part of the section the ponds appear to be less ephemeral, being the aquatic systems more stable for ostracods development. Variations in the water temperature and salinity have been observed along the section, which are related to changes in the local pluviometric regime. On the other hand, the presence of micromammals in one of the studied samples has allowed the precise dating of this section. Thus, the presence of Armantomys daamsi dates the Cenicero section as Agenian (lower Miocene), local zone Y2 (MN2).En este trabajo se realiza, por vez primera, un análisis paleoambiental y bioestratigráfico de los depósitos aluviales del Mioceno inferior de la sección de Cenicero (sector NO de la Cuenca del Ebro; N de la Península Ibérica), a partir de las asociaciones de ostrácodos y micromamíferos preservadas en estos materiales. Una de las principales características de esta sección es la inusual abundancia de ejemplares de ostrácodos no transportados, en comparación con otras secciones europeas de edad y ambiente sedimentario similares, lo que permite hacer inferencias paleoambientales precisas. La variación en las asociaciones de ostrácodos identificadas, defini-das por especies como Cyclocypris laevis, Ilyocypris bradyi, Ilyocypris gibba, Limnocythere sp. o Pseudocandona parallela, parece sugerir el desarrollo de pequeños cuerpos de agua dulce, someros y efímeros, enmarcados en un ambiente general aluvial distal y/o de llanura de inundación. Hacia techo de la sección, se registra una mayor permanencia temporal de estas acumulaciones y condiciones más estables y favorables del medio para el desarrollo de los ostrácodos. Así mismo, se observan variaciones en la temperatura y salinidad del agua a lo largo de la sección, que podrían estar relacionadas con cambios en el régimen pluviométrico local. La presencia de micromamíferos en uno de los niveles estudiados ha permitido obtener una datación precisa de la sección. Así, la aparición de Armantomys daamsi sitúa la sección de Cenicero dentro de la zona local Y2 (MN2) de edad Ageniense (Mioceno inferior)
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