Effects of strain and stocking density on leg health, activity, and use of enrichments in conventional broiler chicken production.

Conventional broiler production needs to evolve towards more animal-friendly production systems in order to meet increasing consumer concerns regarding animal welfare. Genetics and stocking density are 2 of the most promising leads to make this change possible. In this study, 6 strains with different growth rates (42-61 g/d) were reared at contrasting densities: 37 kg/m² (HD) and 29 kg/m² (LD). At the same body weight of 1.80-1.95 kg, we evaluated how growth rate and stocking density influenced broiler behaviors (general activity, interactions with enrichments), broiler health (mortality, leg problems, cleanliness and plumage growth) and litter quality. Density did not affect body weight, mortality or behaviors. For all strains, LD was associated with a lower prevalence of hock burns, a better gait score, and improved litter quality and broiler cleanliness. For the 3 strains most affected by pododermatitis, a lower prevalence was observed in LD than in HD pens. Fewer birds were inactive and more birds were standing and interacting with the enrichments (as proposed in the experiment) as soon as the growth rate was lower than that of the control strain (Ross 308). Others welfare indicators such as gait score, plumage growth improved as well. Litter humidity decreased with growth rate, contributing to better leg conditions and cleaner breasts. The prevalence of hock burns and certain behaviors (i.e., the proportion of birds grooming or walking/running) were not affected by growth rate. The proportion of birds foraging was higher at a lower growth rate. These results suggest that reducing growth rate as a preliminary measure, and reducing density as a supplementary one, would improve conventional broiler welfare.

Ultrasonic thermometry simulation in a random fluctuating medium: Evidence of the acoustic signature of a one-percent temperature difference.

We study the development potential of ultrasonic thermometry in a liquid fluctuating sodium environment similar to that present in a Sodium-cooled Fast Reactor, and thus investigate if and how ultrasonic thermometry could be used to monitor the sodium flow at the outlet of the reactor core. In particular we study if small temperature variations in the sodium flow of e.g. about 1% of the sodium temperature, i.e., about 5°C, can have a reliably-measurable acoustic signature. Since to our knowledge no experimental setups are available for such a study, and considering the practical difficulties of experimentation in sodium, we resort to a numerical technique for full wave propagation called the spectral-element method, which is a highly accurate finite-element method owing to the high-degree basis functions it uses. We obtain clear time-of-flight variations in the case of a small temperature difference of one percent in the case of a static temperature gradient as well as in the presence of a random fluctuation of the temperature field in the turbulent flow. The numerical simulations underline the potential of ultrasonic thermometry in such a context.

Microbubble cloud characterization by nonlinear frequency mixing.

In the frame of the fourth generation forum, France decided to develop sodium fast nuclear reactors. French Safety Authority requests the associated monitoring of argon gas into sodium. This implies to estimate the void fraction, and a histogram indicating the bubble population. In this context, the present letter studies the possibility of achieving an accurate determination of the histogram with acoustic methods. A nonlinear, two-frequency mixing technique has been implemented, and a specific optical device has been developed in order to validate the experimental results. The acoustically reconstructed histograms are in excellent agreement with those obtained using optical methods.

Applying nonlinear resonant ultrasound spectroscopy to improving thermal damage assessment in concrete.

Nonlinear resonant ultrasound spectroscopy (NRUS) consists of evaluating one or more resonant frequency peak shifts while increasing excitation amplitude. NRUS exhibits high sensitivity to global damage in a large group of materials. Most studies conducted to date are aimed at interrogating the mechanical damage influence on the nonlinear response, applying bending, or longitudinal modes. The sensitivity of NRUS using longitudinal modes and the comparison of the results with a classical linear method to monitor progressive thermal damage (isotropic) of concrete are studied in this paper. In addition, feasibility and sensitivity of applying shear modes for the NRUS method are explored.

Coupling an ultrasonic propagation code with a model of the heterogeneity of multipass welds to simulate ultrasonic testing.

The knowledge of the anisotropic and heterogeneous behaviour of the material is the key point for understanding ultrasonic testing. In the case of austenitic stainless steel multipass welds, there was no exact knowledge. The succession of passes and complex solidification processes makes the modelling of the resulting grain orientation difficult. The MINA model allows such a description. Coupling this model with the new propagation code ATHENA permits a very good understanding of the propagation of elastic waves in this kind of complex media. After discussing the existing models of grains orientations for multipass welds, we show how the new MINA model allows to simulate the anisotropic heterogeneous structure in a more realistic manner. We introduce the simulated grains structure and the real one, obtained by macrographs, into the ATHENA propagation code. We obtain a very good correlation between the two simulated propagations. A first experimental application is also successful. We show in a quantitative and qualitative way that the modelling results are close to the experimental measurements on a thick austenitic weld.

[Is the target of anti-cardiolipin antibodies the same in Gougerot-Sjögren syndrome and lupus erythematosus disseminatus?]. / La cible des anticorps anti-cardiolipine est-elle la même au cours du syndrome de Gougerot-Sjögren et au cours du lupus érythémateux disséminé?

Forty-seven patients were diagnosed as having systemic lupus erythematosus (SLE) and 34 patients primary Sjögren's syndrome (SS); 30 controls were also studied. Anti cardiolipin (CL), anti double-stranded DNA (ds DNA) and anti single-stranded DNA (ss DNA) antibodies were determined by the enzyme-linked immunosorbent assay. Elevated anti-CL antibody levels were detected in 47.8 p. 100 (n = 46) of patients with SLE and in 85.3 p. 100 (n = 34) of patients with SS, but only once in controls. Elevated ss DNA were detected in 91.5 p. 100 (n = 47) of patients with SLE and in 18.3 p. 100 of patients with SS but never in controls. Elevated anti-ss DNA were detected in 93.3 p. 100 and 97.1 p. 100 respectively of patients with SLE and SS and in 3.3 p. 100 of controls. There was no correlation between anti-CL and thrombosis, circulating lupus anti coagulant or VDRL. The most striking association, however, was between anti-CL and anti ss-DNA antibodies in SLE. There was no correlation between anti-CL and anti ds-DNA antibodies in SLE patients. Anti CL antibodies were correlated both to ss-DNA and anti ds-DNA in SS patients. Absorption of positive anti-CL antibodies sera were done on DNA (ss-DNA and ds-DNA) affinity column chromatography: anti-CL antibodies were absorbed only by ss DNA in SLE and by both ss DNA and ds DNA in SS.

Nonorgan-specific autoantibodies and immunoglobulin allotypes in relatives of patients with monoclonal gammopathy.

Polyclonal immunoglobulin increase, rheumatoid factor, antinuclear antibodies and cold lymphocytotoxins were detected 10, 8, 7 and 8 times, respectively, in a group of these informative families (22, 17 and 29 subjects tested, respectively). Each family included at least 1 subject with a monoclonal gammopathy in addition to that of the proband. No correlation could be shown between any of these abnormalities and Gm haplotypes. Nonetheless, it is worth noting that 6 out of 41 relatives under 30 years of age had cold lymphocytotoxins.