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Search Results: 1 - 10 of 111927 matches for " O. Morata "
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Multitransitional observations of the CS core of L673
O. Morata,J. M. Girart,R. Estalella
Physics , 2002, DOI: 10.1051/0004-6361:20021103
Abstract: A multitransitional study with the BIMA interferometric array was carried out toward the starless core found in the L673 region, in order to study the small-size structure of the cores detected with previous single--dish observations, which provides us with a test of the predictions of the chemical model of Taylor et al. (1996; 1998). We detected emission in the CS (2-1), N2H+ (1-0), and HCO+ (1-0) lines. Several clumps of size ~0.08 pc were found for each line distributed all over the region where previous single-dish emission was found (Morata et al. 1997). Each molecular transition traces differently the clump distribution, although in some cases the detected clumps are coincident. The distribution of the N2H+ emission and the single-dish NH3 emission are coincident and compatible with an origin in the same gas. The large fraction of missing flux measured for the CS (2-1) transition can be explained if the cloud is formed by a clumpy and heterogeneous medium. Four positions were selected to derive the abundance ratios [N2H+/CS] and [HCO+/CS] from the molecular column density determinations, and to compare them with the values predicted by the chemical model. The model was able to explain the interferometric observations, and, in particular, the chemical differentiation of the detected clumps and the coincidence of the NH3 and N2H+ emissions. The lack of HCO+ towards the two selected positions that trace the more evolved clumps cannot be accounted for by the model, but it is possibly due to strong self-absorption. We propose a classification of the studied clumps according to the stage of chemical evolution indicated by the molecular abundances.
Observing a column-dependent zeta in dense interstellar sources: the case of the Horsehead Nebula
P. B. Rimmer,E. Herbst,O. Morata,E. Roueff
Physics , 2011, DOI: 10.1051/0004-6361/201117048
Abstract: Context: Observations of small carbon-bearing molecules such as CCH, C4H, c-C3H2, and HCO in the Horsehead Nebula have shown these species to have higher abundances towards the edge of the source than towards the center. Aims: Given the determination of a wide range of values for zeta (s-1), the total ionization rate of hydrogen atoms, and the proposal of a column-dependent zeta(N_H), where N_H is the total column of hydrogen nuclei, we desire to determine if the effects of zeta(N_H) in a single object with spatial variation can be observable. We chose the Horsehead Nebula because of its geometry and high density. Method: We model the Horsehead Nebula as a near edge-on photon dominated region (PDR), using several choices for zeta, both constant and as a function of column. The column-dependent zeta functions are determined by a Monte Carlo model of cosmic ray penetration, using a steep power-law spectrum and accounting for ionization and magnetic field effects. We consider a case with low-metal elemental abundances as well as a sulfur-rich case. Results: We show that use of a column-dependent zeta(N_H) of 5(-15) s-1 at the surface and 7.5(-16) s-1 at Av = 10 on balance improves agreement between measured and theoretical molecular abundances, compared with constant values of zeta.
Francesc Morata
Revista CIDOB d'Afers Internacionals , 2006,
Abstract: In his conclusions on the general subject of “Turkey and the EU: Charting the Course Ahead”, the author points out the main challenges that Turkey and the EU must confront on their long road to integration, and he manifests the importance of building bridges, using all of the political resources available, as well as taking advantage of one of theprincipal resources of European governance: networks.
Water maser detections in southern candidates to post-AGB stars and Planetary Nebulae
O. Suárez,J. F. Gómez,L. F. Miranda,J. M. Torrelles,Y. Gómez,G. Anglada,O. Morata
Physics , 2009, DOI: 10.1051/0004-6361/200911777
Abstract: 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 $< -32 \deg$. 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.
Rapid Differential Diagnosis between Extrapulmonary Tuberculosis and Focal Complications of Brucellosis Using a Multiplex Real-Time PCR Assay
María Isabel Queipo-Ortu?o, Juan D. Colmenero, Pilar Bermudez, María José Bravo, Pilar Morata
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0004526
Abstract: Background Arduous to differ clinically, extrapulmonary tuberculosis and focal complications of brucellosis remain important causes of morbidity and mortality in many countries. We developed and applied a multiplex real-time PCR assay (M RT-PCR) for the simultaneous detection of Mycobacterium tuberculosis complex and Brucella spp. Methodology Conventional microbiological techniques and M RT-PCR for M. tuberculosis complex and Brucella spp were performed on 45 clinical specimens from patients with focal complications of brucellosis or extrapulmonary tuberculosis and 26 control samples. Fragments of 207 bp and 164 bp from the conserved region of the genes coding for an immunogenic membrane protein of 31 kDa of B. abortus (BCSP31) and the intergenic region SenX3-RegX3 were used for the identification of Brucella and M. tuberculosis complex, respectively. Conclusions The detection limit of the M RT-PCR was 2 genomes per reaction for both pathogens and the intra- and inter-assay coefficients of variation were 0.44% and 0.93% for Brucella and 0.58% and 1.12% for Mycobacterium. M RT-PCR correctly identified 42 of the 45 samples from patients with tuberculosis or brucellosis and was negative in all the controls. Thus, the overall sensitivity, specificity, PPV and NPV values of the M RT PCR assay were 93.3%, 100%, 100% and 89.7%, respectively, with an accuracy of 95.8% (95% CI, 91.1%–100%). Since M RT-PCR is highly reproducible and more rapid and sensitive than conventional microbiological tests, this technique could be a promising and practical approach for the differential diagnosis between extrapulmonary tuberculosis and focal complications of brucellosis.
Millimetric and sub-millimetric observations of IRAS 05327+3404 "Holoea" in M36
O. Morata,Y. J. Kuan,P. T. P. Ho,H. C. Huang,E. A. Magnier,R. Zhao-Geisler
Physics , 2013, DOI: 10.1088/0004-6256/146/3/49
Abstract: The transition between the proto-star, Class I, and the pre-main sequence star, Class II, phases is still one of the most uncertain, and important, stages in the knowledge of the process of formation of an individual star, because it is the stage that determines the final mass of the star. We observed the YSO "Holoea", associated with IRAS 05327+3404, which was classified as an object in transition between the Class I and Class II phases with several unusual properties, and appears to be surrounded by large amounts of circumstellar material. We used the SMA and BIMA telescopes at millimeter and sub-millimeter wavelengths to observe the dust continuum emission and the CO (1-0) and (2-1), HCO+ (1-0) and (3-2), and HCN (1-0) transitions in the region around IRAS 05327+3404. We detected two continuum emission peaks at 1.1-mm: SMM 1, the sub-mm counterpart of IRAS 05327+3404, and SMM 2, ~6 arcsec to the West. The emissions of the three molecules show marked differences. The CO emission near the systemic velocity is filtered out by the telescopes, and CO mostly traces the high-velocity gas. The HCO+ and HCN emissions are more centrally concentrated around the central parts of the region, and show several intensity peaks coincident with the sub-mm continuum peaks. We identify two main molecular outflows: a bipolar outflow in an E-W direction that would be powered by SMM 1 and another one in a NE direction, which we associate with SMM 2. We propose that the SMM sources are probably Class I objects, with SMM 1 in an earlier evolutionary stage.
Nature and P-T-t constraints of very low-grade metamorphism in the Triassic-Jurassic basins, Coastal Range, central Chile
Belmar,Mauricio; Morata,Diego;
Revista geológica de Chile , 2005, DOI: 10.4067/S0716-02082005000200002
Abstract: triassic-jurassic volcano-sedimentary sequences in the coastal range of central chile (34° 45/35°20's) from the vichuquén-tilicura and huala?é-gualleco basins display metamorphic assemblages indicative of very low-grade conditions. triassic and lower jurassic metapelites achieved anchizonal conditions (ic, bo, coal-rank and fluid inclusions data: p ?1.3, t?190) at 181-184 ma, under geothermal gradient of ?35°ckm-1 during extensional geodynamic conditions. nevertheless, in stratigraphically higher mafic volcanic sequences, of middle to late jurassic age, the presence of chlorite (xc =0.98-0.99), three types of epidote (xfe3+ = 41.14±0.90, 30.08±1.53 and 18.05±1.75), titanite, fe-rich and fe-poor pumpellyite and hydrogarnet (+albite and quartz) are indicative of re-equilibration under prehnite-pumpellyite facies conditions (p ?3 kbar, t ?300°c) and variable oxygen fugacity. a change from an extensional setting (with maximum basin subsidence and development of burial very low-grade metamorphism in the triassic-lower jurassic metapelitic sequences) to a compressional setting (with local overthrusting of triassic and lower jurassic sequences over middle to late jurassic volcano-sedimentary sequences) is proposed to explain the contrasting metamorphic conditions between triassic-lower jurassic metapelites and middle-late jurassic metabasites
El Knowledge Center de DiamondCluster International
Aparicio i Morata, Iria
BiD : Textos Universitaris de Biblioteconomia i Documentació , 2001,
Abstract: Es descriu el centre de documentació de DiamondCluster International i l evolució que ha seguit des de la seva creació fins ara. Se n'expliquen els processos bàsics, l estructura i el paper que té dins l organització.
Saúde da fonoaudiologia no Brasil
Thais C. Morata
Revista CEFAC , 2010, DOI: 10.1590/s1516-18462010000400001
Basura electrónica Electronic trash
Pedro Costa Morata
Teknokultura : Revista de Cultura Digital y Movimientos Sociales , 2012,
Abstract: Este texto es un comentario acerca del vídeo viral "Buy it, Use it, Break it, Junk it, it's Toxic" de la organización Greenpeace sobre el problema presentado por la “basura electrónica”, una amenaza ambiental relativamente reciente derivado del ingente consumo de aparatos electrónicos. This text is a comment about the viral video "Buy it, Use it, Break it, Junk it, it's Toxic", from Greenpeace, about the problem presented by the "electronic trash", a relatively recently environmental threat derived from the enormous consumption electronic artifacts.
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