433 research outputs found
Impact of Type of K Fertilizer on DCAD of Fen Grassland in Northeast Germany
A lower DCAD is required in the diet fed during the prepartum period, but increasing the DCAD of diets fed during lactation increased milk yield and dry matter intake (Overton 2020). We conducted 3 cutting date/type of fertilizer trials, harvested with 5, 4 and 3 cuts per year over 3 years. Compared to the chloride based K fertilizer, the application of a sulphate based K fertilizer did not change dry matter yield and fodder quality (NEL-, XP-content) but led to significant higher DCAD in the grass in cut 1 - 3 of all trials over 3 years. The increase of DCAD amounted to approximately 100 to 150 in the first, 50 to 100 in the second and 40 to 80 meq kg-1 DM in the third cut. The findings correspond to results from grassland on other soils in Germany
An improved sliding mode control (SMC) approach for enhancement of communication delay in vehicle platoon system
Vehicle platoon systems are widely recognized as a key enabler to address mass-transport. Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) are two technologies that drive platooning. The inter-vehicle spacing and the collaboration velocity in the platoon are main important parameters that must be controlled. Recently, a new mass-transport system has been proposed, called the Tracked Electric Vehicles (TEV). In TEV, the inter-vehicular spacing is reduced to only a quarter of the regular car length and cars drive at 200km/h which enable mass transport at uniform speed. However, conventional radar based Adaptive Cruise Control (ACC) system fail to control each vehicle in these scenarios. Lately, Sliding Mode Control (SMC) has been applied to control platoons with communication technology but with low speed and without delay. This paper proposes a novel SMC design for TEV using global dynamic information with the communication delay. Also, graph theory has been employed to investigate different V2V communication topology structures. To address the issues of node vehicle stability and string stability, Lyapunov candidate function is chosen and developed for in-depth analysis. In addition, this paper, uses first-order vehicle models with different acceleration and deceleration parameters for simulation validations under communication delay. The results show that this novel SMC has a significant tolerance ability therefore meet the design requirements of TEV
IL-22 mediates goblet cell hyperplasia and worm expulsion in intestinal helminth infection.
Type 2 immune responses are essential in protection against intestinal helminth infections. In this study we show that IL-22, a cytokine important in defence against bacterial infections in the intestinal tract, is also a critical mediator of anti-helminth immunity. After infection with Nippostrongylus brasiliensis, a rodent hookworm, IL-22-deficient mice showed impaired worm expulsion despite normal levels of type 2 cytokine production. The impaired worm expulsion correlated with reduced goblet cell hyperplasia and reduced expression of goblet cell markers. We further confirmed our findings in a second nematode model, the murine whipworm Trichuris muris. T.muris infected IL-22-deficient mice had a similar phenotype to that seen in N.brasiliensis infection, with impaired worm expulsion and reduced goblet cell hyperplasia. Ex vivo and in vitro analysis demonstrated that IL-22 is able to directly induce the expression of several goblet cell markers, including mucins. Taken together, our findings reveal that IL-22 plays an important role in goblet cell activation, and thus, a key role in anti-helminth immunity
Flavor decomposition of the sea quark helicity distributions in the nucleon from semi-inclusive deep-inelastic scattering
Double-spin asymmetries of semi-inclusive cross sections for the production
of identified pions and kaons have been measured in deep-inelastic scattering
of polarized positrons on a polarized deuterium target. Five helicity
distributions including those for three sea quark flavors were extracted from
these data together with re-analyzed previous data for identified pions from a
hydrogen target. These distributions are consistent with zero for all three sea
flavors. A recently predicted flavor asymmetry in the polarization of the light
quark sea appears to be disfavored by the data.Comment: 5 pages, 3 figure
Nuclear Polarization of Molecular Hydrogen Recombined on a Non-metallic Surface
The nuclear polarization of molecules formed by recombination
of nuclear polarized H atoms on the surface of a storage cell initially coated
with a silicon-based polymer has been measured by using the longitudinal
double-spin asymmetry in deep-inelastic positron-proton scattering. The
molecules are found to have a substantial nuclear polarization, which is
evidence that initially polarized atoms retain their nuclear polarization when
absorbed on this type of surfac
Single-spin asymmetries in semi-inclusive deep-inelastic scattering on a transversely polarized hydrogen target
Single-spin asymmetries for semi-inclusive electroproduction of charged pions
in deep-inelastic scattering of positrons are measured for the first time with
transverse target polarization. The asymmetry depends on the azimuthal angles
of both the pion () and the target spin axis () about the virtual
photon direction and relative to the lepton scattering plane. The extracted
Fourier component \cmpi is a signal of the previously unmeasured quark
transversity distribution, in conjunction with the so-called Collins
fragmentation function, also unknown. The Fourier component \smpi of the
asymmetry arises from a correlation between the transverse polarization of the
target nucleon and the intrinsic transverse momentum of quarks, as represented
by the previously unmeasured Sivers distribution function. Evidence for both
signals is observed, but the Sivers asymmetry may be affected by exclusive
vector meson productio
First Measurement of the Tensor Structure Function of the Deuteron
The \Hermes experiment has investigated the tensor spin structure of the
deuteron using the 27.6 GeV/c positron beam of \Hera. The use of a tensor
polarized deuteron gas target with only a negligible residual vector
polarization enabled the first measurement of the tensor asymmetry \At and
the tensor structure function \bd for average values of the Bj{\o}rken
variable and of the squared four-momentum transfer . The quantities \At and \bd are found to be
non-zero. The rise of \bd for decreasing values of can be interpreted to
originate from the same mechanism that leads to nuclear shadowing in
unpolarized scattering
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