908 research outputs found

    Opportunities (and challenges) in dairy cattle cognition research: A key area needed to design future high welfare housing systems

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    The ability of dairy cattle to adapt to husbandry systems and management routines is crucial for ensuring higher welfare and efficient production. However, this ability can be compromised by our limited knowledge of their cognitive abilities, which may result in suboptimal husbandry and management standards. In this narrative review, we highlight three topics of cattle cognition research that are currently understudied, and yet key to developing future high welfare dairy cattle housing systems: 1) transmission of information from cow to calf, 2) mechanisms to attenuate fear, and 3) cognitive processes involved in the human-cattle relationship. We review the currently available literature on all three topics and highlight promising research areas from an animal husbandry point of view. We conclude that future studies should focus on elucidating what, and how much, calves learn from their dam during prolonged cow-calf contact in dairy cattle systems. Such information could constitute an important part of the discussion of whether to keep cows and calves together for a longer time after calving in the dairy industry. Fear in the cattle group might be lowered by the use of calm companions and future studies could uncover if attenuation of fear might even be induced by conditioning positive experiences of cattle with unrelated stimuli such as odours. Lastly, the human-cattle relationship might benefit from utilising the already established training regimes from other species, for example positive reinforcement training or target training, which may have the potential to decrease risk of injury during handling for both the cow and the handler

    Comparison of Navier Stokes and Reduced Navier Stokes unsteady computation in a stenosis

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    Comparison of Navier Stokes and Reduced Navier Stokes unsteady computation in a stenosis

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    Differential roles of p39Mos–Xp42Mpk1 cascade proteins on Raf1 phosphorylation and spindle morphogenesis in Xenopus oocytes

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    AbstractFully-grown G2-arrested Xenopus oocytes resume meiosis upon hormonal stimulation. Resumption of meiosis is characterized by germinal vesicle breakdown, chromosome condensation, and organization of a bipolar spindle. These cytological events are accompanied by activation of MPF and the p39Mos–MEK1–Xp42Mpk1–p90Rsk pathways. The latter cascade is activated upon p39Mos accumulation. Using U0126, a MEK1 inhibitor, and p39Mos antisense morpholino and phosphorothioate oligonucleotides, we have investigated the role of the members of the p39Mos–MEK1–Xp42Mpk1–p90Rsk in spindle morphogenesis. First, we have observed at a molecular level that prevention of p39Mos accumulation always led to MEK1 phosphorylation defects, even when meiosis was stimulated through the insulin Ras-dependent pathway. Moreover, we have observed that Raf1 phosphorylation that occurs during meiosis resumption was dependent upon the activity of MEK1 or Xp42Mpk1 but not p90Rsk. Second, inhibition of either p39Mos accumulation or MEK1 inhibition led to the formation of a cytoplasmic aster-like structure that was associated with condensed chromosomes. Spindle morphogenesis rescue experiments using constitutively active Rsk and purified murine Mos protein suggested that p39Mos or p90Rsk alone failed to promote meiotic spindle organization. Our results indicate that activation of the p39Mos–MEK1–Xp42Mpk1–p90Rsk pathway is required for bipolar organization of the meiotic spindle at the cortex

    Measurement of electron-neutrino electron elastic scattering

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    The cross section for the elastic scattering reaction nu_e+e- -> nu_e+e- was measured by the Liquid Scintillator Neutrino Detector using a mu+ decay-at-rest nu_e beam at the Los Alamos Neutron Science Center. The standard model of electroweak physics predicts a large destructive interference between the charge current and neutral current channels for this reaction. The measured cross section, sigma_{nu_e e-}=[10.1 +- 1.1(stat.) +- 1.0(syst.)]x E_{nu_e} (MeV) x 10^{-45} cm^2, agrees well with standard model expectations. The measured value of the interference parameter, I=-1.01 +- 0.13(stat.) +- 0.12(syst.), is in good agreement with the standard model expectation of I^{SM}=-1.09. Limits are placed on neutrino flavor-changing neutral currents. An upper limit on the muon-neutrino magnetic moment of 6.8 x 10^{-10} mu_{Bohr} is obtained using the nu_mu and \bar{nu}_mu fluxes from pi+ and mu+ decay.Comment: 22 pages, 11 figure

    Uncooled IRFPA developments review

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    Abstract Today, large number of un cooled infrared detector developments are under progress due to the availability of silicon technology that enablesJealization of low cost 2D IR arrays. Development of such a structure involves a lot of trade-offs between the different parameters which characterize these detectors: • infrared flux absorption, • measurement of the temperature increase due to the incoming infrared flux absorption, • thermal insulation between detector and readout circuit, • readout of thermometer temperature variation. These trade-offs explain the number of different approaches that are under worldwide development. We present a rapid survey of the state of the art through these developments. LETlfUR has chosen resistive amorphous silicon as thermometer for his uncooled microbolometer development. After a first phase dedicated to the acquisition of the most important detector parameters in order to help the modeling and the technological development, an IRCMOS laboratory model (256 x 64 with a pitch of 50 I-Im) was realized and characterized. It was shown that NETD of 80 mK at ff1.25 Hz and 300 K background can be obtained with high thermal insulation (1.2 10 7 K/W)

    The OPERA experiment Target Tracker

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    The main task of the Target Tracker detector of the long baseline neutrino oscillation OPERA experiment is to locate in which of the target elementary constituents, the lead/emulsion bricks, the neutrino interactions have occurred and also to give calorimetric information about each event. The technology used consists in walls of two planes of plastic scintillator strips, one per transverse direction. Wavelength shifting fibres collect the light signal emitted by the scintillator strips and guide it to both ends where it is read by multi-anode photomultiplier tubes. All the elements used in the construction of this detector and its main characteristics are described.Comment: 25 pages, submitted to Nuclear Instrument and Method

    Constraining Non-Standard Interactions of the Neutrino with Borexino

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    We use the Borexino 153.6 ton.year data to place constraints on non-standard neutrino-electron interactions, taking into account the uncertainty in the 7Be solar neutrino flux, and backgrounds due to 85Kr and 210Bi beta-decay. We find that the bounds are comparable to existing bounds from all other experiments. Further improvement can be expected in Phase II of Borexino due to the reduction in the 85Kr background.Comment: 21 pages, 16 pdf figures, 2 tables. Analysis updated including the uncertainty in sin^2\theta_{23}. Accepted in JHE
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