3-D Kinematics of the HH 110 jet

We present new results on the kinematics of the jet HH 110. New proper motion measurements have been calculated from [SII] CCD images obtained with a time baseline of nearly fifteen years. HH 110 proper motions show a strong asymmetry with respect to the outflow axis, with a general trend of pointing towards the west of the axis direction. Spatial velocities have been obtained by combining the proper motions and radial velocities from Fabry-Perot data. Velocities decrease by a factor ~3 over a distance of ~10$^{18}$ cm, much shorter than the distances expected for the braking caused by the jet/environment interaction. Our results show evidence of an anomalously strong interaction between the outflow and the surrounding environment, and are compatible with the scenario in which HH 110 emerges from a deflection in a jet/cloud collision.Comment: (1)Universitat de Barcelona; (2)UNAM; (3)UPC; (4)University of Hawaii; (5)Southern Astrophysical Research Telescope. 9 pages; 7 Figures Accepted by A&

A survey of IRAS young stellar object candidates: Searching for large-scale Herbig-Haro objects

Context. Jets and outflows are associated with young stellar objects across the stellar mass spectrum, from brown dwarf protostars to massive Ae/Be stars. Frequently the jet morphology is spatially discontinuous because of the temporal variability of the ejection from the driving source. Images covering a wide field of view around the jet-driving source are useful to map the large-scale jet emission and to explore the mass ejection history. Aims. The aim of our work was to search for large-scale optical Herbig-Haro (HH) objects lying in a wide field around a sample of IRAS sources, which are candidates to trace young stellar objects. Methods. Deep narrowband images through the Hα and [S II ] emission lines, and through an off-line continuum filter, covering a wide (∼15 0 ) field around the IRAS targets were acquired. The images in the three filters were analyzed to identify shock-excited line emission (i.e., HH) in contrast to scattered line emission. Results. New images of a sample of 15 IRAS sources, obtained in a homogeneous way are presented. HH emission was detected in six fields, and the astrometry of the knot features is given. The nature of the extended emission as scattered emission around nine of the IRAS targets is confirmed. For seven IRAS sources with unclear optical counterparts, a more plausible counterpart is proposed. A refined value of the source distance is reported for seven targets. An update of the main data available for each of the sampled fields, including images from public data archives, is also presented

A comparison of generalized multinomial logit, random parameters logit, wtp-space and latent class models to studying consumers' preferences for animal welfare

The European societies are requiring that animals to be raised as closely as possible to their natural conditions. The growing concerns about animal welfare is resulting in continuous modifications of regulations and policies that led to ban of a number of intensive farming methods. The European authorities consider the pig welfare as a priority issue. They are studying to ban surgical pig castration by 2018, which may seriously affect markets and consumers due to boar tainted-meat. This study analysed consumers’ preferences and acceptance regarding an alternative to castration of high-level boar-taint frankfurter sausages. Non-hypothetical discrete choice experiments was applied by creating a real shopping scenario before and after tasting the products. Data were collected for a sample of 150 consumers from the metropolitan area of Madrid, Spain. Different modelling approaches (Generalized Multinomial Logit-GMNL, Random Parameters Logit-RPL, WTP-space and Latent Class-LC models) were applied to figure out which model have the best goodness of fit. Results showed the appropriateness of the proposed alternative by using a new flavour as a masking strategy. When consumers tasted the products, they showed their willingness to pay a premium for this flavour. The WTP space model showed the best goodness of fit in terms of likelihood, Akaike information criterion and McFadden Pseudo R2. Furthermore, the degree of randomness identified by the scale parameter is also estimated. Uncertainty in selection decreased significantly after the sensory experiencePostprint (published version

Towards entire male pigs in Europe: a perspective from the Spanish supply chain

In pig production, surgical castration is primarily performed to avoid boar taint and for management purposes. The European Commission plans to end surgical piglet castration voluntarily by 2018. The aim of this study was to assess the opinions and attitudes of Spanish stakeholders from the entire pork chain regarding this plan. Two methodologies were used: focus groups with 26 participants (qualitative method) were conducted with representatives of farmers, the meat industry, government institutions, retailers (including butchers), HORECA and consumers, and 127 face-to-face surveys at butchers (quantitative method) were carried out. These include an analytical hierarchical process to assess the determining factors when purchasing fresh pig meat. The results showed that a potential end of pig castration in Europe is not anticipated to affect conventional pig production in Spain. However, butchers are worried of negative effects on high quality meat and meat products, where surgical castration of pigs plays an important role.Postprint (published version

Shaping point- and mirror-symmetric proto-planetary nebulae by the orbital motion of the central binary system

We present 3D hydrodynamical simulations of a jet launched from the secondary star of a binary system inside a proto-planetary nebula. The secondary star moves around the primary in a close eccentric orbit. From the gasdynamic simulations we compute synthetic [NII] 6583 emission maps. Different jet axis inclinations with respect to the orbital plane, as well as different orientations of the flow with respect to the observer are considered. For some parameter combinations, we obtain structures that show point- or mirror-symmetric morphologies depending on the orientation of the flow with respect to the observer. Furthermore, our models can explain some of the emission distribution asymmetries that are summarized in the classification given by Soker & hadar (2002).Comment: 15 pages, 3 figures, 2 tables, Accepted in Apj Letter

VLA ammonia observations of L1287: analysis of the "Guitar" core and two filaments

The present work aims at studying the dense gas of the molecular cloud LDN 1287 (L1287), which harbors a double FU Ori system, an energetic molecular outflow and a still-forming cluster of deeply embedded low-mass, young stellar objects, showing a high level of fragmentation. We present optical Halpha and [SII], and VLA NH$_3$ (1,1) and (2,2) observations with an angular resolution of ~3.5''. The observed NH$_3$ spectra have been analyzed with the HfS tool, fitting simultaneously three different velocity components. The NH$_3$ emission from L1287 comes from four different structures: a core associated with RNO 1, a guitar-shaped core (the "Guitar") and two interlaced filaments (the Blue and Red Filaments) roughly centered towards the binary FU Ori system RNO 1B/C and its associated cluster. Regarding the Guitar Core, there are clear signatures of gas infall onto a central mass that has been estimated to be ~2.1 $M_\odot$. Regarding the two filaments, they have radii ~0.03 pc, masses per unit length ~50 $M_\odot$ pc$^{-1}$, and are near isothermal equilibrium. A central cavity, probably related with the outflow, and also traced by the Halpha and [SII] emission, is identified, with several young stellar objects near its inner walls. Both filaments show clear signs of perturbation by the high-velocity gas of the outflows driven by one or several young stellar objects of the cluster. The Blue and Red filaments are coherent in velocity and have nearly subsonic gas motions, except at the position of the embedded sources. Velocity gradients across the Blue Filament can be interpreted either as infalling material onto the filament or rotation. Velocity gradients along the filaments are interpreted as infall motions towards a gravitational well at the intersection of both filaments.Comment: Accepted for publication in Astronomy and Astrophysic

Acceptability of meat with different levels of boar taint compounds for Spanish and English consumers.

Postprint (published version