Capillary Waves at Liquid/Vapor Interfaces: A Molecular Dynamics Simulation

Evidence for capillary waves at a liquid/vapor interface are presented from extensive molecular dynamics simulations of a system containing up to 1.24 million Lennard-Jones particles. Careful measurements show that the total interfacial width depends logarithmically on $L_\parallel$, the length of the simulation cell parallel to the interface, as predicted theoretically. The strength of the divergence of the interfacial width on $L_\parallel$ depends inversely on the surface tension $\gamma$. This allows us to measure $\gamma$ two ways since $\gamma$ can also be obtained from the difference in the pressure parallel and perpendicular to the interface. These two independent measures of $\gamma$ agree provided that the interfacial order parameter profile is fit to an error function and not a hyperbolic tangent, as often assumed. We explore why these two common fitting functions give different results for $\gamma$

Avoiding Calving Problems.

2 p

A Comparison of Synovex ONE® Alone to Synovex Choice® Followed by Synovex Plus® as Implant Strategies for Finishing Heifers

A commercial feedlot study utilizing 1,737 crossbred heifers (initial BW 690 lb) compared the effect of two implant strategies [Synovex ONE Feedlot (day 0) or Synovex Choice (day 0) followed by Synovex Plus (day 95)] on performance and carcass characteristics. No differences were observed in carcass weight, final body weight, or gain, but heifers implanted with Synovex ONE Feedlot had slightly greater feed conversion and greater intake than heifers implanted using Synovex Choice/Synovex Plus. Heifers implanted with Synovex Choice/Synovex Plus had lower marbling score and yield grade, higher dressing percentage, and greater loin muscle area compared to heifers implanted with Synovex ONE Feedlot. Cattle implanted with Synovex ONE Feedlot showed a tendency for better quality grading compared to heifers implanted with Synovex Choice/Synovex Plus. These data suggest that implanting heifers with Synovex ONE Feedlot gives comparable growth to heifers implanted with Synovex Choice followed by Synovex Plus, with some changes in fatness when fed equal days

Effects of Optaflexx Fed in Combination with MGA on Feedlot Heifer Performance

A commercial feedlot experiment was conducted using 1,807 heifers to evaluate the effects of Optaflexx fed in combination with MGA on finishing heifer performance. In heifers receiving MGA throughout the entire 126-143 day feeding period, feeding Optaflexx for the last 31-38 days increased ADG and hot carcass weight compared to heifers fed MGA but not Optaflexx. Heifers fed MGA and Optaflexx had increased DMI, improved feed efficiency and increased final live weight. Carcass quality measurements were not influenced by treatment

Spreading Dynamics of Polymer Nanodroplets

The spreading of polymer droplets is studied using molecular dynamics simulations. To study the dynamics of both the precursor foot and the bulk droplet, large drops of ~200,000 monomers are simulated using a bead-spring model for polymers of chain length 10, 20, and 40 monomers per chain. We compare spreading on flat and atomistic surfaces, chain length effects, and different applications of the Langevin and dissipative particle dynamics thermostats. We find diffusive behavior for the precursor foot and good agreement with the molecular kinetic model of droplet spreading using both flat and atomistic surfaces. Despite the large system size and long simulation time relative to previous simulations, we find no evidence of hydrodynamic behavior in the spreading droplet.Comment: Physical Review E 11 pages 10 figure

Evaluation of Revalor®-G as an Initial Implant for Yearling Steers

Three hundred thirty-six English crossbred steers (715 lb) were used to compare effects of reimplanting with Revalor®-S (administered on day 66) after three different initial implants (administered on day zero), to single implantation with Revalor-S (administered on day zero or day 66). Over the entire study, implanted steers gained faster and more efficiently than non-implanted control steers. Steers implanted initially with Revalor-G or Synovex-S gained faster than steers implanted only once. Of the three reimplant treatments, only those initially implanted with Revalor-G had improved feed efficiency compared with single-implanted steers on a live basis. Compared to non-implanted controls, marbling score was reduced only when Synovex-S or Ralgro was used as initial implants

Evaluation of Initial Implants for Finishing Heifers

A commercial feedyard experiment evaluated initial implant strategies for feedlot heifers. Heifers were administered either Revalor-IH or Synovex-H at initial processing, with both treatment groups receiving Revalor-200 as a common terminal implant. Implanting heifers initially with Revalor-IH improved feed efficiency and ADG compared to heifers implanted initially with Synovex-H. In addition, Revalor- IH implanted heifers had higher marbling scores while 58% more carcasses achieved the upper two-thirds Choice category. There were no differences in USDA yield grades. Selling Revalor- IH implanted heifers on a carcass merit basis returned $14.22/head more than Synovex-H implanted heifers. New reduced-dose initial implants can improve both feed efficiency and marbling scores, suggesting carcass quality can be positively influenced with no negative impact on growth performance