4,378 research outputs found

    Substellar Objects in Nearby Young Clusters (SONYC) VIII: Substellar population in Lupus 3

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    SONYC -- Substellar Objects in Nearby Young Clusters -- is a survey program to investigate the frequency and properties of substellar objects in nearby star-forming regions. We present a new imaging and spectroscopic survey conducted in the young (~1 Myr), nearby (~200 pc) star-forming region Lupus 3. Deep optical and near-infrared images were obtained with MOSAIC-II and NEWFIRM at the CTIO-4m telescope, covering ~1.4 sqdeg on the sky. The i-band completeness limit of 20.3 mag is equivalent to 0.009-0.02 MSun, for Av \leq 5. Photometry and 11-12 yr baseline proper motions were used to select candidate low-mass members of Lupus 3. We performed spectroscopic follow-up of 123 candidates, using VIMOS at the Very Large Telescope (VLT), and identify 7 probable members, among which 4 have spectral type later than M6.0 and Teff \leq 3000K, i.e. are probably substellar in nature. Two of the new probable members of Lupus 3 appear underluminous for their spectral class and exhibit emission line spectrum with strong Halpha or forbidden lines associated with active accretion. We derive a relation between the spectral type and effective temperature: Teff=(4120 +- 175) - (172 +- 26) x SpT, where SpT refers to the M spectral subtype between 1 and 9. Combining our results with the previous works on Lupus 3, we show that the spectral type distribution is consistent with that in other star forming regions, as well as is the derived star-to-BD ratio of 2.0-3.3. We compile a census of all spectroscopically confirmed low-mass members with spectral type M0 or later.Comment: Accepted by Astrophysical Journa

    Prosociality and life satisfaction: a daily-diary investigation among Spanish university students

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    With a diary study, we tested the positive effect of prosociality on life satisfaction. Fifty-six Spanish undergraduate students (45 females; Mage = 21.08 years) rated their life satisfaction, prosociality, self-esteem, and physical appearance for 5 consecutive days. Multilevel results indicated that within-individual positive deviations in prosociality (i.e., behaving more prosocial than usual) were uniquely and significantly associated with higher life satisfaction on that specific day. Students’ self-esteem, physical appearance, and positive daily events were also predictive of life satisfaction. Exploratory analyses revealed that the positive effect of prosociality on life satisfaction was significant only for those students with low or medium levels of satisfaction with their physical appearance. The findings are discussed in relation to the individual determinants of subjective well-being during early adulthood

    Bibliometrics as a Tool for Environmental Management at the University of Havana

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    Within the framework of the University of Havana Environment Network (Red MA-UH), much environmental research is carried out, but most of it is never implemented or applied due to poor visibility and a lack of efficient strategic alliances. Today, the results of much of this research become either grey literature or Cuban publications with poor visibility, and therefore they can’t be used for solving environmental problems affecting society. Nevertheless, this research could be used to help solve socio-environmental problems if decision-makers and international organizations were made aware of the results and provided funding to put them into practice. Research results are increasingly being disseminated on an international scale, so their visibility can be enhanced and funding and scientific collaboration can be gotten more easily, allowing the University of Havana Environment Network’s research to have the desired social effects. The present work is aimed at examining high-impact publications included in the Scimago Journal & Country Rank (SJCR) portal, specifically in the field of environmental sciences. Metrical indicators were used to show the University of Havana Environment Network how to make its research results more visible by identifying international high-impact publications in the environmental sciences, to enhance the visibility of research carried out at the University of Havana, which contributes, in turn, to implementation in environmental management, rational use and equitable distribution of resources, and the promotion of local development by means of environmental management strategies, guaranteeing a harmonious relationship between society and natur

    An X-ray study of the SNR G344.7-0.1 and the central object CXOU J170357.8-414302

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    Aims. We report results of an X-ray study of the supernova remnant (SNR) G344.7-0.1 and the point-like X-ray source located at the geometrical center of the SNR radio structure. Methods. The morphology and spectral properties of the remnant and the central X-ray point-like source were studied using data from the XMM-Newton and Chandra satellites. Archival radio data and infrared Spitzer observations at 8 and 24 μ\mum were used to compare and study its multi-band properties at different wavelengths. Results. The XMM-Newton and Chandra observations reveal that the overall X-ray emission of G344.7-0.1 is extended and correlates very well with regions of bright radio and infrared emission. The X-ray spectrum is dominated by prominent atomic emission lines. These characteristics suggest that the X-ray emission originated in a thin thermal plasma, whose radiation is represented well by a plane-parallel shock plasma model (PSHOCK). Our study favors the scenario in which G344.7-0.1 is a 6 x 10^3 year old SNR expanding in a medium with a high density gradient and is most likely encountering a molecular cloud on the western side. In addition, we report the discovery of a soft point-like X-ray source located at the geometrical center of the radio SNR structure. The object presents some characteristics of the so-called compact central objects (CCO). However, its neutral hydrogen absorption column (N_{H}) is inconsistent with that of the SNR. Coincident with the position of the source, we found infrared and optical objects with typical early-K star characteristics. The X-ray source may be a foreground star or the CCO associated with the SNR. If this latter possibility were confirmed, the point-like source would be the farthest CCO detected so far and the eighth member of the new population of isolated and weakly magnetized neutron stars.Comment: 9 pages, 8 figures, accepted for publication in Astronomy and Astrophysics. Higher resolution figures can be seen on A&

    Selective maintenance of Drosophila tandemly arranged duplicated genes during evolution

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    Genes occurring in conserved, tandemly-arrayed clusters in Drosophila melanogaster are co-expressed to a much higher extent than other duplicated genes
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