Assessing Italians' Preferences for Mountain Beef Production Using a Best-Worst Scaling Approach

The European Union (EU) regulation on mountain food products represents a great opportunity for beef producers in mountain areas, particularly as the quality-certified food has received more attention from European consumers in recent years. However, for a food-quality system-such as the European Commission's mountain labeling scheme-to be effective, the regulation standards must meet consumer expectations. In Italy, there are few studies on consumer preferences regarding beef and none focused on meat produced in mountain areas. To help fill this gap, this study assessed the preferences of Italian citizens for attributes associated with beef produced in mountain areas and contrasted the results with the EU regulation on mountain food products. Furthermore, factors that explain the heterogeneity of Italians' preferences regarding beef production attributes were analyzed. Data were collected online using a consumer panel, and a best-worst scaling method and latent class analysis were used. The results indicate that Italians expect mountain beef to be healthier and produced according to higher animal welfare standards. Such preferences reveal the existence of a gap between what Italians expect and the quality standards of the EU regulation on mountain food products, a situation that may jeopardize the objectives of the European Commission's mountain labeling scheme

Relationship among surgical volume, repair quality, and perioperative outcomes for repair of mitral insufficiency in a mitral valve reference center

ObjectiveAlthough it has been demonstrated that the repair rates and quality of the repair of mitral insufficiency are superior in mitral valve reference centers, it has not been studied whether an advantage exists for perioperative morbidity and mortality. We report 1 surgeon's evolution over 7 years, specifically considering the changes in perioperative morbidity and mortality.MethodsWe performed a retrospective review of 1054 patients who had undergone elective, day-of-surgery-admission mitral valve repair by a single surgeon (D.H.A.) at our institution from April 2005 to June 2012. The outcome variables studied were operative mortality (30-day or in-hospital mortality, if longer), length of stay, low cardiac output state after cardiopulmonary bypass, and major morbidity.ResultsThe overall operative mortality was 0.58%. Of the 1054 patients, 31% developed a low cardiac output state postoperatively and 6.52% experienced at least 1 of the composite morbidity events. Increased aortic crossclamp times were significantly and independently associated with a low cardiac output state, length of stay, and morbidity. When divided by service year, a statistically and clinically significant decrease was found in the aortic crossclamp time, despite an increase in the complexity of cases. The morbidity decreased concurrently with the decreases in crossclamp times.ConclusionsAs the number of mitral valve repairs performed each year by a single surgeon at a single institution increased, morbidity, including postoperative heart function and length of stay, decreased. This was demonstrated to occur in large part from a reduction in the aortic crossclamp times, despite an increase in the complexity of the procedures. This further demonstrates the value of reference centers for mitral valve surgery

Spatially valid proprioceptive cues improve the detection of a visual stimulus

Vision and proprioception are the main sensory modalities that convey hand location and direction of movement. Fusion of these sensory signals into a single robust percept is now well documented. However, it is not known whether these modalities also interact in the spatial allocation of attention, which has been demonstrated for other modality pairings. The aim of this study was to test whether proprioceptive signals can spatially cue a visual target to improve its detection. Participants were instructed to use a planar manipulandum in a forward reaching action and determine during this movement whether a near-threshold visual target appeared at either of two lateral positions. The target presentation was followed by a masking stimulus, which made its possible location unambiguous, but not its presence. Proprioceptive cues were given by applying a brief lateral force to the participant’s arm, either in the same direction (validly cued) or in the opposite direction (invalidly cued) to the on-screen location of the mask. The d′ detection rate of the target increased when the direction of proprioceptive stimulus was compatible with the location of the visual target compared to when it was incompatible. These results suggest that proprioception influences the allocation of attention in visual spac

Understanding the shape of the halo-mass and galaxy-mass cross-correlation functions

We use the Millennium Simulation to measure the cross-correlation between halo centres and mass (or equivalently the average density profiles of dark haloes) in a LCDM cosmology. We present results for radii in the range 10 kpc/h < r < 30 Mpc/h for halo masses in the range 4e10 Msol/h < M200 < 4e14 Msol/h. Both at z=0 and at z=0.76 these cross-correlations are surprisingly well fit by approximating the inner region by a density profile of NFW or Einasto form, the outer region by a biased version of the linear mass autocorrelation function, and by adopting the maximum of the two where they are comparable. We use a simulation of the formation of galaxies within the Millennium Simulation to explore how these results are reflected in cross-correlations between galaxies and mass. These are directly observable through galaxy-galaxy lensing. Here also we find that simple models can represent the simulation results remarkably well, typically to < 10%. Such models can be used to extend our results to other redshifts, to cosmologies with other parameters, and to other assumptions about how galaxies populate dark haloes. The characteristic features predicted in the galaxy-galaxy lensing signal should provide a strong test of the LCDM cosmology as well as a route to understanding how galaxies form within it.Comment: 14 pages, 15 figures submitted to MNRAS, replaced incorrect figure fil

Weak Lensing by Galaxies in Groups and Clusters: I.--Theoretical Expectations

Galaxy-galaxy lensing is rapidly becoming one of the most promising means to accurately measure the average relation between galaxy properties and halo mass. In order to obtain a signal of sufficient signal-to-noise, one needs to stack many lens galaxies according to their property of interest, such as luminosity or stellar mass. Since such a stack consists of both central and satellite galaxies, which contribute very different lensing signals, the resulting shear measurements can be difficult to interpret. In the past, galaxy-galaxy lensing studies have either completely ignored this problem, have applied rough isolation criteria in an attempt to preferentially select `central' galaxies, or have tried to model the contribution of satellites explicitely. However, if one is able to {\it a priori} split the galaxy population in central and satellite galaxies, one can measure their lensing signals separately. This not only allows a much cleaner measurement of the relation between halo mass and their galaxy populations, but also allows a direct measurement of the sub-halo masses around satellite galaxies. In this paper, we use a realistic mock galaxy redshift survey to show that galaxy groups, properly selected from large galaxy surveys, can be used to accurately split the galaxy population in centrals and satellites. Stacking the resulting centrals according to their group mass, estimated from the total group luminosity, allows a remarkably accurate recovery of the masses and density profiles of their host haloes. In addition, stacking the corresponding satellite galaxies according to their projected distance from the group center yields a lensing signal that can be used to accurate measure the masses of both sub-haloes and host haloes. (Abridged)Comment: 16 pages, 10 figures, Accepted for publication in MNRA

Modeling of Polymer Clay Nanocomposite for a Multiscale Approach

The mechanical property enhancement of polymer reinforced with nano-thin clay platelets (of high aspect ratio) is associated with a high polymer-filler interfacial area per unit volume. The ideal case of fully separated (exfoliated) platelets is generally difficult to achieve in practice: a typical nanocomposite also contains multilayer stacks of intercalated platelets. Here we use numerical modelling to investigate how the platelet properties affect the overall mechanical properties. The configuration of platelets is modelled using a statistical interpretation of the Representative Volume Element (RVE) approach, in which an ensemble of "sample" heterogeneous material is generated (with periodic boundary conditions). A simple Monte Carlo algorithm is used to place non-intersecting platelets in the RVE according to a specified set of statistical distributions. The effective stiffness of the platelet-matrix system is determined by measuring the stress (using standard Finite Element analysis) produced as a result of applying a small deformation to the boundaries, and averaging over the entire statistical ensemble. In this work we determine the way in which the platelet properties (curvature, filling fraction, stiffness, aspect ratio) and the number of layers in the stack affect the overall stiffness enhancement of the nanocomposite. Thus, we bridge the gap between behaviour on the macroscopic scale with that on the scale of the nano-reinforcement, forming part of a multi-scale modelling framework.Comment: 39 pages, 19 figure

Spin and structural halo properties at high redshift in a LCDM Universe

In this paper, we examine in detail the key structural properties of high redshift dark matter haloes as a function of their spin parameter. We perform and analyze high resolution cosmological simulations of the formation of structure in a LCDM Universe. We study the mass function, ellipticities, shapes, density profiles, rotation curves and virialization for a large sample of dark matter haloes from z = 15 - 6. We also present detailed convergence tests for individual haloes. We find that high spin haloes have stronger clustering strengths (up to 25%) at all mass and redshift ranges at these early epochs. High redshift spherical haloes are also up to 50% more clustered than aspherical haloes. High spin haloes at these redshifts are also preferentially found in high density environments, and have more neighbors than their low spin counterparts. We report a systematic offset in the peak of the circular velocity curves for high and low spin haloes of the same mass. Therefore, estimating halo masses without knowledge of the spin, using only the circular velocity can yield errors of up to 40%. The strong dependence of key structural properties on spin that we report here likely have important implications for studies of star formation and feedback from these galaxies.Comment: 14 pages, 10 figures. Accepted to MNRAS

Electronic Structure of the BaFe2_2As2_2 Family of Iron Pnictides

We use high resolution angle-resolved photoemission spectroscopy to study the band structure and Fermi surface topology of the BaFe$_2$As$_2$ iron pnictides. We observe two electron bands and two hole bands near the X-point, $(\pi,\pi)$ of the Brillouin zone, in the paramagnetic state for different doping levels, including electron-doped Ba(Co$_{0.06}$Fe$_{0.94}$)$_2$As$_2$, undoped BaFe$_2$As$_2$, and hole-doped Ba$_{0.6}$K$_{0.4}$Fe$_2$As$_2$. Among these four bands, only the electron bands cross the Fermi level, forming two electron pockets around X, while the hole bands approach but never reach the Fermi level. We show that the band structure of the BaFe$_2$As$_2$ family matches reasonably well with the prediction of LDA calculations after a momentum-dependent shift and renormalization. Our finding resolves a number of inconsistencies regarding the electronic structure of pnictides.Comment: 5 pages, 4 figure