Ractopamine hydrochloride (RAC) and zilpaterol hydrochloride (ZH) are beta-adrenergic agonists that improve growth performance and affect carcass characteristics. The objective of this study was to evaluate the comparative effects of RAC and ZH when fed to beef steers during the last 33 d of the finishing period. Three hundred crossbred beef steers (516 +/- 8 kg) were grouped by BW, BCS, and breed type and randomly assigned to 1 of 3 treatments (10 steers per pen; 10 pens per treatment). Treatments were control (no beta-agonists added), RAC (200 mg of ractopaminexhdx(-1)d(-1), for 33 d), or ZH (75 mg of zilpaterolxanimalx(-1)d(-1), for 30 d, removed 3 d for required withdrawal period). Steers were slaughtered, carcass characteristics were evaluated, and cut-out yields were determined. Both RAC and ZH increased final BW, ADG, feed efficiency (G:F), and HCW compared with controls (P < 0.05). Compared with RAC, ZH decreased ADG, ADFI, and final BW, but increased HCW and dressing percentage (P < 0.05). Carcass yield was not affected by RAC in this experiment, whereas ZH decreased adjusted fat thickness and KPH, increased ribeye area, improved yield grade, and increased cut-out yields, when compared with controls (P < 0.05). Marbling, lean maturity, and skeletal maturity were not different between treatments (P > 0.05). Steaks from RAC steers had greater (P < 0.05) Warner-Bratzler shear force (WBSF) values than steaks from control steers at 3 and 7 d of aging, but did not differ from controls after 14 d of aging. Steaks from ZH steers had greater WBSF values (P < 0.05) than steaks from controls and RAC steaks throughout the 21-d postmortem aging period. Although both beta-adrenergic agonists were effective at improving feedlot performance, RAC showed no negative effect on WBSF after 14 d, whereas WBSF values for ZH steaks were significantly greater than controls after 21 d.

The experimental binding energies of single-particle and single-hole neutron states belonging to neutron shells that extend from N = 126 to 184 and 82 to 126 respectively, have been reproduced by solving the Schrödinger equation with a potential that has two components: the generalized Woods-Saxon (GWS) potential and the spin-orbit (SO) coupling term. The GWS potential contains the traditional WS potential plus a term (SU) whose intensity reaches a maximum in the nuclear surface.Our results indicate the existence of a explicit relationship between the strength of the SU potential and the orbital angular momentum quantum number of the state. This dependence has been used to make reasonable predictions for the excitation energy centroids of states located inside and outside the neutron shells investigated. Comparisons are made with results reported in previous investigations.

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A protocol for transferring an unknown single qubit state evidences quantum features when the average fidelity of the outcomes is, in principle, greater than 2/3. We propose to use the probabilistic and unambiguous state extraction scheme as a mechanism to redistribute the fidelity in the outcome of the standard teleportation when the process is performed with an X−state as a noisy quantum channel. We show that the entanglement of the channel is necessary but not sufficient in order for the average fidelity f X to display quantum features, i.e., we find a threshold C X for the concurrence of the channel. On the other hand, if the mechanism for redistributing fidelity is successfully then we find a filtrable outcome with average fidelity f X,0 that can be greater than f X .In addition, we find the threshold concurrence of the channel C X,0 in order for the average fidelity f X,0 to display quantum features and surprisingly, the threshold concurrence C X,0 can be less than C X . Even more, we find some special cases for which the threshold values become zero.