17,279 research outputs found
Morpho-kinematic analysis of the point-symmetric, bipolar planetary nebulae Hb 5 and K 3-17, a pathway to poly-polarity
The kinematics of the bipolar planetary nebulae Hb~5 and K 3-17 are
investigated in detail by means of a comprehensive set of spatially resolved
high spectral resolution, long-slit spectra. Both objects share particularly
interesting characteristics, such as a complex filamentary, rosette-type
nucleus, axial point-symmetry and very fast bipolar outflows. The kinematic
information of Hb~5 is combined with {\it HST} imagery to construct a detailed
3D model of the nebula using the code SHAPE. The model shows that the large
scale lobes are growing in a non-homologous way. The filamentary loops in the
core are proven to actually be secondary lobes emerging from what appears to be
a randomly punctured, dense, gaseous core and the material that forms the point
symmetric structure flows within the lobes with a distinct kinematic pattern
and its interaction with the lobes has had a shaping effect on them. Hb~5 and
K~3-17 may represent a class of fast evolving planetary nebulae that will
develop poly-polar characteristics once the nebular core evolves and expands.Comment: 19 pages, 8 figures. To appear in The Astrophysical Journa
Science and Business
There are two kinds of scientists in evolutionary studies that need a space of debate: the specialists in evolutionary studies in business and all other evolutionary scientists in general. The themes of the discussion are the behaviour, growth, reproduction, and organizational structures of the firm
A methodology to introduce sustainability into the Final Year Project to foster sustainable engineering projects
The introduction of sustainability skills into higher education curricula is a natural effect of the increasing importance of sustainability in our daily lives. Topics like green computing, sustainable design or environmental engineering have become part of the knowledge required by today’s engineers. Furthermore, we strongly believe that the introduction of this skill will eventually enable future engineers to develop sustainable products, services and projects. The Final Year Project is the last academic stage facing students and a step towards their future professional engineering projects. As such, it constitutes a rehearsal for their professional future and an ideal opportunity for reflecting on whether their Final Year Project is sustainable or not, and to what extent. It also provides a good tool for reviewing the lessons learned about sustainability during the degree course and for applying them in a holistic and integrated way. In this paper, we present a guide that allows both students and advisors to think carefully about the sustainability of engineering projects, in particular the Final Year Project.Postprint (author’s final draft
Incidence and type of bicuspid aortic valve in two model species
Incidence and type of bicuspid aortic
valve in two model species.
MC Fernández 1,2, A López-García 1,2, MT Soto 1,
AC Durán 1,2 and B Fernández 1,2.
1 Department of Animal Biology, Faculty of Science, University of Málaga, Spain.
2 Biomedical Research Institute of Málaga (IBIMA),
University of Málaga, Spain.
Bicuspid aortic valve (BAV) is the most frequent human congenital cardiac malformation, with an incidence of 1–2% worldwide. Two morphological types exist: type A (incidence 0.75–1.25%) and type B (incidence 0.25–0.5%), each with a distinct aetiology and natural history. Currently, ten animal models of BAV have been described in two different rodent species: one spontaneous Syrian hamster (Mesocricetus auratus) model of BAV type A and nine mutant laboratory mouse (Mus musculus) models of BAV type B. It remains to be elucidated whether the mutations leading to BAV in these models are typespecific or whether there are inter-specific differences regarding the type of BAV that hamsters, mice and humans may develop.
To solve this issue, we have characterized the incidence and types of BAVs in four inbred, two outbred and two hybrid lines of Syrian hamsters (n=4,340) and in three inbred, three outbred and one hybrid lines of laboratory mice (n=1,661) by means of stereomicroscopy and scanning electron microscopy. In addition, we have reviewed and calculated the incidence and type of BAVs in the published papers dealing with this anomaly in mice.
Our results indicate that the Syrian hamster develops BAVs type A and B including a variety of morphologies comparable to those of humans, whereas the mouse develops only BAVs type B with a short spectrum of valve morphologies. Thus, inter-specific differences between human and mouse aortic valves must be taken into consideration when studying valve disease in murine models.
This work was supported by P10-CTS-6068.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. P10-CTS-6068
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