Milking cows once daily influences behavior and udder firmness at peak and mid lactation

Our aim was to evaluate the effects of once-daily milking on the welfare of dairy cows in a pastoral-based farming system. There are concerns that cows milked only once daily may experience discomfort associated with udder distension. We evaluated the behavior, including lying time and postures, grazing patterns, and kicking behavior in the parlor, and measures of udder firmness in cows milked once daily in 2 experiments: 1) at peak lactation, comparing cows milked once (1×) or twice-daily (2×) from the time of calving (n = 4 groups; 1× and 2× treatments); and 2) during the transition from 2× to 1× milking at mid lactation (n = 12 groups; 1×, 2×, and 2× to 1× treatments or TRANS). At peak lactation, cows milked 1× were more likely to lie with their hind legs touching the body than cows milked 2×. There were no differences in udder firmness (1×: 10.0 vs. 2×: 9.9 ± 0.13 g of force) or kicking (1×: 25 vs. 2×: 24 ± 7.8%) behavior in the parlor. In the second experiment, milking frequency was reduced from 2× to 1× and this change resulted in an increase in udder firmness (1 ×: 9.1, 2×: 9.3, and TRANS: 9.5 ± 0.14 g of force). Despite these differences in udder firmness, lying time (1×: 10.1, 2×: 9.5, and TRANS: 9.6 ± 0.38 h/24 h), postures, and concentrations of fecal glucocorticoid metabolites (1×: 10.0, 2×: 10.5, and TRANS: 10.4 ± 0.49 ng/g of feces in the 3 d after transition) in cows milked 1× or 2× were similar. Although milking frequency did not influence total time spent grazing, the diurnal grazing pattern of cows milked 2× was disrupted by afternoon milking at both peak and mid lactation. Cows milked 2× were able to compensate for this by grazing more after the return to pasture (DIM 153 to 155, 1×: 52 vs. 2×: 66 ± 6.2 min/90 min of grazing). Cows milked 1× had slightly longer strides than 2× cows at mid lactation (1×: 0.73, 2×: 0.70, and TRANS: 0.70 ± 0.014 strides/m). In conclusion, under our experimental conditions, we found no overt changes in behavior or physiology to indicate that the welfare of cows milked 1× is impaired.     

Effects of halothane genotype and pre-slaughter treatment on pig meat quality. Part 2. Physico-chemical traits of cured-cooked ham and sensory traits of cured-cooked and dry-cured hams

Forty-eight castrated F₂ offspring of Piétrain and Large White pigs were allocated to a 3×2 factorial design in order to study the interactive effect of halothane genotype (NN, Nn and nn) and pre-slaughter treatment (referred to as ’Experimental’ (EXP) and ’Commercial-like’ (COL) conditions; the latter involving short transportation, mixing unfamiliar pigs and slaughtering shortly after transport) on the qualities of cured-cooked and dry-cured hams. At 24 h post mortem, the hams were collected and assigned to cured-cooked (right ham) and dry-cured (left ham) ham processing. A sample of M. semimembranosus (SM) was collected before cooked ham processing, was used for chemical composition analysis, cured and then cooked at various temperatures. Cooking losses and compression tests were carried out after cooking on these SM samples. The water and collagen content of SM muscle was significantly higher in nn pigs compared with the two other genotypes. At all cooking temperatures (60, 65 and 70 °C), SM muscles from nn pigs showed higher cooking losses and instrumentally assessed toughness than the other genotypes, the heterozygous pigs being intermediate. The technological yield of cured-cooked ham processing was lower in nn, compared with NN and Nn animals. Cooked hams from nn pigs were drier, tougher, stringier and less smooth than NN and Nn pigs. The heterozygous pigs were similar to normal pigs for all texture characteristics with the exception of toughness for which they got a significantly higher score than NN pigs. The pigs slaughtered under the COL conditions had a better slice cohesiveness and a significantly lower dryness, than pigs slaughtered under the EXP conditions. The effect of HAL genotype on slice cohesiveness was significant only when pigs were slaughtered under the EXP conditions. Dry-cured hams from nn pigs showed significantly more visual defects, but were less tough, smoother and more fondant (softer) than NN and Nn pigs. The dry-cured hams from pigs slaughtered under the COL conditions had a better cohesiveness between muscles and a more intense yellow colour of fat than those from pigs slaughtered under the EXP conditions. COL pigs were also judged significantly less tough, smoother and more fondant than EXP ones. Overall, the effects of pre-slaughter treatment were small compared with those of the HAL genotype. The effects of HAL genotype on the sensory traits of cured-cooked ham were similar to those reported for fresh meat. However, the good textural characteristics of dry-cured ham processed from HAL positive pigs are somewhat surprising and need to be confirmed.     

Remarks on the Equivalence of Full Additivity and Monotonicity for the Entanglement Cost

We analyse the relationship between the full additivity of the entanglement cost and its full monotonicity under local operations and classical communication. We show that the two properties are equivalent for the entanglement cost. The proof works for the regularization of any convex, subadditive, and asymptotically continuous entanglement monotone, and hence also applies to the asymptotic relative entropy of entanglement. Presented at the 38th Symposium on Mathematical Physics “Quantum Entanglement & Geometry“, Toruń, June 4–7, 2006.     

Hot entanglement in a simple dynamical model

Abstract

The theory of balanced homodyne and heterodyne detection is developed for inputs in which the signal field is in an arbitrary quantum state and the local-oscillator field is in a highly excited coherent state. Exact expressions are derived for the photocount moment-generating functions in the special case of a coherent signal. For more general signals, the first two moments of the photocount probability distribution are determined. The moments are evaluated for the examples of a coherent signal with a chaotic noise component, and for squeezed light derived from a degenerate and from a non-degenerate parametric amplifier. The corresponding moments for direct detection are obtained so that comparisons can be made. The Kelley-Kleiner photocount distribution formula is adapted to balanced detection schemes. Light beams are characterized throughout by their energy fluxes, and the theory accordingly describes steady-state experiments.     

Applications,interet, limites des methodes de sondages et traines electriques a la reconnaissance de travaux souterrains. Experience tiree des reconnaissances realisees sur plus de 100 km de galeries du canal de provence.

Bulletin of Engineering Geology and the Environment - La Société du Canal de Provence a réalisé plus de 100 kilomètres de galeries de 2,4 à5 m de diamètre, dans...     

Inclusion of aerodynamic non-equilibrium effects in supersonic plasma jet enthalpy probe measurements

Low pressure plasma spraying (LPPS) is a thermal spraying technique that has found a niche for low oxidation products. It uses a low pressure environment (i.e., chamber pressure between 2 and 90 kPa) and yields supersonic plasma jets. The enthalpy probe technique is a common measurement method in plasmas. However LPPS jets are difficult to diagnose as their supersonic nature forces the apparition of a shock wave in front of any measuring device inserted in the jet. Incomplete or erroneous assumptions are usually invoked to overcome the difficulties associated with this shock wave and carry out the LPPS jet diagnosis from enthalpy probe measurements. In this work, a new device is designed to gain access to an additional physical quantity, which is needed to assess the aerodynamic non-equilibrium state of the jet. It is combined with enthalpy probe measurements, and the resulting set of experimental data is used with a numerical procedure based on gas dynamics theory, yielding free-stream supersonic plasma jet values from the measurements behind the induced shock wave. The results agree well with the phenomenology of supersonic jets in aerodynamic nonequilibrium. However this new method is restricted by the local thermodynamic equilibrium assumption, which is directly linked with the pressure and temperature conditions of the plasma jet.     

Secondary electron emission from distributed ion scattering off surfaces for space instrumentation

We present an alternative method for generating start electrons for time of flight (TOF) space plasma analyzers. The technique presented here takes advantage of the processes occurring during the scattering of the particles off a surface, i.e., kinetic electron emission. The use of a thin microchannel plate as a scattering surface allows us to distribute this surface along a single plane normal to the particle velocity. The uncertainty on the TOF distance is thus minimized, allowing a greater mass resolution. The first tests carried out showed that a mass resolution of 10 for a beam energy of 10 keV is easily reachable.     

Warping a single Mn acceptor wavefunction by straining the GaAs host

Transition-metal dopants such as Mn determine the ferromagnetism in dilute magnetic semiconductors such as Ga(1-x)Mn(x)As. Recently, the acceptor states of Mn dopants in GaAs were found to be highly anisotropic owing to the symmetry of the host crystal. Here, we show how the shape of such a state can be modified by local strain. The Mn acceptors near InAs quantum dots are mapped at room temperature by scanning tunnelling microscopy. Dramatic distortions and a reduction in the symmetry of the wavefunction of the hole bound to the Mn acceptor are observed originating from strain induced by quantum dots. Calculations of the acceptor-state wavefunction in the presence of strain, within a tight-binding model and within an effective-mass model, agree with the experimentally observed shape. The magnetic easy axes of strained lightly doped Ga(1-x)Mn(x)As can be explained on the basis of the observed local density of states for the single Mn spin.