1,578 research outputs found
Impact of Teat Order on Feed Consumption in Swine from Birth to Nursery
A relationship between teat order and feed consumption has been assumed in pigs, but no study has looked at this exact relationship. Pigs were observed shortly after birth to be in either a cranial, middle, or caudal teat positon. Growth performance data and active and total plasma ghrelin concentrations were analyzed at birth, weaning, and at the end of the nursery stage of production to see if a relationship with teat order was present. Overall, no effect of teat order was found on average daily gain, average daily feed intake, gain-to-feed ratio, or body weight among pigs from each section of the udder. Differences did occur during certain stages of nursery, which can be of economic importance to producers. No difference was seen in active or total ghrelin levels or the active-to-total ghrelin ratio in relation to teat order, although there were differences in active and total ghrelin concentrations among the sampling days. Further research should be carried out to investigate what factors would contribute to this data contradicting previous inferences about the relationship of teat order and feed consumption in pigs
Theory of single-photon transport in a single-mode waveguide coupled to a cavity containing a two-level atom
The single-photon transport in a single-mode waveguide, coupled to a cavity
embedded with a two-leval atom is analyzed. The single-photon transmission and
reflection amplitudes, as well as the cavity and the atom excitation
amplitudes, are solved exactly via a real-space approach. It is shown that the
dissipation of the cavity and of the atom respectively affects distinctively on
the transport properties of the photons, and on the relative phase between the
excitation amplitudes of the cavity mode and the atom.Comment: 28 pages, 6 figures. Accepted by Physical Review A (2009
Satisfying the Direct Laser Acceleration Resonance Condition in a Laser Wakefield Accelerator
In this proceeding, we show that when the drive laser pulse overlaps the
trapped electrons in a laser wakefield accelerator (LWFA), those electrons can
gain energy from direct laser acceleration (DLA) over extended distances
despite the evolution of both the laser and the wake. Through simulations, the
evolution of the properties of both the laser and the electron beam is
quantified, and then the resonance condition for DLA is examined in the context
of this change. We find that although the electrons produced from the LWFA
cannot continuously satisfy the DLA resonance condition, they nevertheless can
gain a significant amount of energy from DLA.Comment: 2014 Advanced Accelerator Concepts Worksho
Excess Kondo resonance in a quantum dot device with normal and superconducting leads: the physics of Andreev-normal co-tunneling
We report on a novel Kondo phenomenon of interacting quantum dots coupled
asymmetrically to a normal and a superconducting lead. The effects of intradot
Coulomb interaction and Andreev tunneling give rise to Andreev bound
resonances. As a result, a new type of co-tunneling process which we term
Andreev-normal co-tunneling, is predicted. At low temperatures, coherent
superposition of these co-tunneling processes induces a Kondo effect in which
Cooper pairs directly participate formation of a spin singlet, leading to four
Kondo resonance peaks in the local density of states, and enhancing the
tunneling current.Comment: 4 pages, 2 figures, Late
Extraordinary Temperature Dependence of the Resonant Andreev Reflection
An extraordinary temperature dependence of the resonant Andreev reflection
via discrete energy level in a normal-metal / quantum-dot / superconductor
(N-QD-S) system is predicted theoretically by using Green function technique.
The width of zero bias conductance peak in N-QD-S is about and does not exhibit thermal broadening, where and
are the coupling strength between QD and leads. Considering the
intra-dot Coulomb interaction, the Coulomb blockade oscillations conducted by
Andreev reflection differs dramatically from that in N-QD-N. Instead of thermal
broadening, finite temperature induces more resonant peaks around the
oscillation peaks of zero temperature. This effect can be applied to determine
the coupling strength and QD level spacing in N-QD-S.Comment: 11 pages, 3 figures, LaTe
- …