1,833 research outputs found

    Pillars of creation amongst destruction: Star formation in molecular clouds near R136 in 30 Doradus

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    New sensitive CO(2-1) observations of the 30 Doradus region in the Large Magellanic Cloud are presented. We identify a chain of three newly discovered molecular clouds we name KN1, KN2 and KN3 lying within 2--14 pc in projection from the young massive cluster R136 in 30 Doradus. Excited H2_2 2.12μ\mum emission is spatially coincident with the molecular clouds, but ionized Brγ\gamma emission is not. We interpret these observations as the tails of pillar-like structures whose ionized heads are pointing towards R136. Based on infrared photometry, we identify a new generation of stars forming within this structure.Comment: Accepted for publication in ApJ (includes 13 pages, 8 figures). For higher resolution figures please see http://www.das.uchile.cl/~vkalari/staplervk.pd

    Stabilizing equilibrium by linear feedback control for controlling chaos in Chen system

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    Stabilization of a chaotic system in one of its unstable equilibrium points by applying small perturbations is studied. A two-stage control strategy based on linear feedback control is applied. Improvement of system performance is addressed by exploiting the ergodicity of the original dynamics and using Lyapunov stability results for control design. Extension to the not complete observability case is also analyzed.Facultad de Ingenierí

    Stabilizing equilibrium by linear feedback control for controlling chaos in Chen system

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    Stabilization of a chaotic system in one of its unstable equilibrium points by applying small perturbations is studied. A two-stage control strategy based on linear feedback control is applied. Improvement of system performance is addressed by exploiting the ergodicity of the original dynamics and using Lyapunov stability results for control design. Extension to the not complete observability case is also analyzed.Facultad de Ingenierí

    Effective tensor forces and neutron rich nuclei

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    We study the effects of the tensor term of the effective nucleon-nucleon interaction on nuclear excited states. Our investigation has been conducted by using a self-consistent Random Phase Approximation approach. We investigate various nuclei in different regions of the isotopes chart. Results for a set of calcium isotopes are shown.Comment: 4 pages, 4 figures, 1 table Proc. 10th International Spring Seminar on Nuclear Physics New Quests in Nuclear Structure, Vietri Sul Mare, May 21-25, 201

    DCIS and LCIS are confusing and outdated terms. They should be abandoned in favor of ductal intraepithelial neoplasia (DIN) and lobular intraepithelial neoplasia (LIN)

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    Abstract The terms ductal and lobular intraepithelial neoplasia (DIN and LIN) were introduced by Tavossoli 15 years ago, who proposed they should replace, respectively, ductal and lobular carcinoma in situ (DCIS and LCIS). This proposal has been slowly gaining ground. We argue that DCIS and LCIS should now be definitively abandoned. Bringing together 'in situ' and other entities into the simpler and more logical DIN/LIN framework–as has been done with intraepithelial neoplasias of cervix, vagina, vulva, prostate, and pancreas–would eliminate the artificial and illogical distinctions between 'not cancers' (e.g. flat epithelial atypia, atypical ductal hyperplasia–now classified as low grade DIN) and 'cancers' (e.g. DCIS–now considered medium–high grade DIN). Elimination of the term 'carcinoma' from entities that cannot metastasize will reduce confusion among health professionals and patients, and contribute to reducing the risk of overtreatment, as well as reducing adverse psychological reactions in patients

    Soft L_e-L_mu-L_tau flavour symmetry breaking and sterile neutrino keV Dark Matter

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    We discuss how a Le−Lμ−LτL_e-L_\mu-L_\tau flavour symmetry that is softly broken leads to keV sterile neutrinos, which are a prime candidate for Warm Dark Matter. This is to our knowledge the first model where flavour symmetries are applied simultaneously to active and sterile neutrinos explaining at the same time active neutrino properties and this peculiar Dark Matter scenario. The essential point is that different scales of the symmetry breaking and the symmetry preserving entries in the mass matrix lead to one right-handed neutrino which is nearly massless compared to the other two. Furthermore, we naturally predict vanishing θ13\theta_{13} and maximal θ23\theta_{23}, while the correct value of θ12\theta_{12} must come from the mixing of the charged leptons. We can furthermore predict an exact mass spectrum for the light neutrinos, which will be testable in the very near future.Comment: 14 page

    Transport, associated handling procedures, conditions and behaviour of calves marketed through Chilean auction markets

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    In Chile, selling animals through livestock markets is common. At markets, stressful events like loading, unloading and travel are at least duplicated. We described procedures associated with transport of calves at 20 markets and evaluated compliance with Chilean law by performing a survey of drivers who transport calves from origin farms to markets (OM) and from markets to destination (MD). During loading and unloading, we evaluated handling by stockpersons, facilities, fitness for transport, and behavioural indicators of the calves through direct observation using protocols. A total of 80% of drivers claimed having the training required by law. The mean travel time was 1 h 31 min for OM and 1 h 44 min for MD journeys (overall range 5 min–40.5 h). Most drivers used bedding material and provided adequate space availability. A total of 99.2% of the observed calves were assessed as fit to transport; slipping, turning back, vocalizing and balking were frequent behaviours observed during loading and unloading. Prohibited practices like prodding and hitting using driving devices were still observed, mainly during loading. Compliance with the law during transport of calves was adhered to; however, the associated handling within markets was still inadequate, evidencing need for training in order to improve animal welfare
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