Effects of corn steep liquor supplementation on intake and digestion of tallgrass prairie hay contaminated with sericea lespedeza

Sericea lespedeza (Lespedeza cuneata) is a noxious weed that infests approximately 600,000 acres of native range in Kansas. Intake of sericea lespedeza by grazing beef cattle is poor due to the presence of condensed tannins in the plant. Condensed tannins reduce protein digestion by beef cattle and may also decrease plant palatability because of their astringent nature. Prolific seed production, in combination with little or no grazing pressure, has contributed to the rapid spread of sericea lespedeza in the Flint Hills. Increasing grazing pressure on sericea lespedeza may reduce seed production and slow its advance; however, the presence of condensed tannins inhibit consumption by grazing animals. Reports have indicated that feed-grade polyethylene glycol may inhibit formation of tannin-protein complexes in the rumen, but beef producers have not widely adopted polyethylene glycol because, at the rates necessary to increase intake of sericea lespedeza, it is cost-prohibitive and disallowed by regulations. Therefore, identifying substances that are generally regarded as safe (GRAS) by the U.S. Food and Drug Administration, cost-effective, and that mitigate the consequences of consuming a diet high in tannins is advantageous. Such information could lead to a degree of biological control of this noxious weed using the most economically important grazer (i.e., beef cattle) in the Flint Hills. Preliminary research in our laboratory indicated that corn steep liquor has binding affinity for condensed tannins that is similar to polyethylene glycol. Therefore, the objective of our study was to determine the effects of corn steep liquor supplementation on intake and digestion of tallgrass prairie hay contaminated by sericea lespedeza

Forage selection preferences of experienced cows and naïve heifers grazing native tallgrass range during winter

Beef Cattle Research, 2011 is known as Cattlemen’s Day, 2011Estimating the nutritive value of a grazing animal’s diet is a significant challenge. Description of the botanical composition of a grazed diet is vital in that regard. Microhistological analysis of fecal material has been used for estimating the botanical composition of wild and domestic ungulate diets since first described by Baumgartner and Martin in 1939. Little research has been conducted on the diet selection preferences of multiparous beef cows compared to primiparous beef cows. We hypothesized that foraging strategies change as cows age. To that end, our objective was to characterize differences in diet selection between experienced multiparous and naïve primiparous beef cows grazing dormant, native tallgrass pastures during winter

Dynamic Vortex Phases and Pinning in Superconductors with Twin Boundaries

We investigate the pinning and driven dynamics of vortices interacting with twin boundaries using large scale molecular dynamics simulations on samples with near one million pinning sites. For low applied driving forces, the vortex lattice orients itself parallel to the twin boundary and we observe the creation of a flux gradient and vortex free region near the edges of the twin boundary. For increasing drive, we find evidence for several distinct dynamical flow phases which we characterize by the density of defects in the vortex lattice, the microscopic vortex flow patterns, and orientation of the vortex lattice. We show that these different dynamical phases can be directly related to microscopically measurable voltage - current V(I) curves and voltage noise. By conducting a series of simulations for various twin boundary parameters we derive several vortex dynamic phase diagrams.Comment: 5 figures, to appear in Phys. Rev.

Correlated evolution of multivariate traits: detecting co-divergence across multiple dimensions

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75039/1/j.1420-9101.2007.01415.x.pd

BIOLEACHING OF COBALT AND ZINC FROM PYRITE ORE IN RELATION TO CALCITIC GANGUE CONTENT

Bioleaching of a pyrite ore containing high concentrations of cobalt (0.1%) and zinc (0.065%) was affected by small amounts of calcitic gangue (from 0.01 to 1.01%). Results from an air-lift percolator and from Erlenmeyer flask experiments show that a small percentage of calcite raises the pH and arrests the growth of the acidophilic bacterium Thiobacillus ferrooxidans. In percolator experiments, when calcite is completely removed by the continuous addition of small quantities of acid, and the pH of the liquor becomes acid, the micro-organism begins to grow and to bio-oxidize the pyrite ore. The growth of T. ferrooxidans shows different lag phase spans (from 13 to 190 days) depending on carbonate dissolution. The metals Fe, Zn and Co are released into the leaching solution together at different rates after a lag-time which depends on calcite concentrations in pyrite gangue. Metal ratios in the mineral bulk are different from those in the liquor, Zn dissolving 5 times more readily than Co. Bioleaching rates for metal removal from pyrite are higher in percolator (for Fe, from 5 to 15 mg/l/h) than in flask experiments (from 0.5 to 2 mg/l/h), but the lag phases are shorter (from 2 to 65 days). The differences between the two systems are related to calcite dissolution and gypsum precipitation

Demonstration of the temporal matter-wave Talbot effect for trapped matter waves

We demonstrate the temporal Talbot effect for trapped matter waves using ultracold atoms in an optical lattice. We investigate the phase evolution of an array of essentially non-interacting matter waves and observe matter-wave collapse and revival in the form of a Talbot interference pattern. By using long expansion times, we image momentum space with sub-recoil resolution, allowing us to observe fractional Talbot fringes up to 10th order.Comment: 17 pages, 7 figure

Kaon Production and Kaon to Pion Ratio in Au+Au Collisions at \snn=130 GeV

Mid-rapidity transverse mass spectra and multiplicity densities of charged and neutral kaons are reported for Au+Au collisions at \snn=130 GeV at RHIC. The spectra are exponential in transverse mass, with an inverse slope of about 280 MeV in central collisions. The multiplicity densities for these particles scale with the negative hadron pseudo-rapidity density. The charged kaon to pion ratios are $K^+/\pi^- = 0.161 \pm 0.002 {\rm (stat)} \pm 0.024 {\rm (syst)}$ and $K^-/\pi^- = 0.146 \pm 0.002 {\rm (stat)} \pm 0.022 {\rm (syst)}$ for the most central collisions. The $K^+/\pi^-$ ratio is lower than the same ratio observed at the SPS while the $K^-/\pi^-$ is higher than the SPS result. Both ratios are enhanced by about 50% relative to p+p and $\bar{\rm p}$+p collision data at similar energies.Comment: 6 pages, 3 figures, 1 tabl

Phi meson production in Au+Au and p+p collisions at sqrt (s)=200 GeV

We report the STAR measurement of Phi meson production in Au+Au and p+p collisions at sqrt (s)=200 GeV. Using the event mixing technique, the Phi spectra and yields are obtained at mid-rapidity for five centrality bins in Au+Au collisions and for non-singly-diffractive p+p collisions. It is found that the Phi transverse momentum distributions from Au+Au collisions are better fitted with a single-exponential while the p+p spectrum is better described by a double-exponential distribution. The measured nuclear modification factors indicate that Phi production in central Au+Au collisions is suppressed relative to peripheral collisions when scaled by the number of binary collisions. The systematics of versus centrality and the constant Phi/K- ratio versus beam species, centrality, and collision energy rule out kaon coalescence as the dominant mechanism for Phi production.Comment: 6 pages, 3 figures, submitted to Phys. Rev. Let

Azimuthal anisotropy at RHIC: the first and fourth harmonics

We report the first observations of the first harmonic (directed flow, v_1), and the fourth harmonic (v_4), in the azimuthal distribution of particles with respect to the reaction plane in Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). Both measurements were done taking advantage of the large elliptic flow (v_2) generated at RHIC. From the correlation of v_2 with v_1 it is determined that v_2 is positive, or {\it in-plane}. The integrated v_4 is about a factor of 10 smaller than v_2. For the sixth (v_6) and eighth (v_8) harmonics upper limits on the magnitudes are reported.Comment: 6 pages with 3 figures, as accepted for Phys. Rev. Letters The data tables are at http://www.star.bnl.gov/central/publications/pubDetail.php?id=3

First upper limits from LIGO on gravitational wave bursts

We report on a search for gravitational wave bursts using data from the first science run of the LIGO detectors. Our search focuses on bursts with durations ranging from 4 ms to 100 ms, and with significant power in the LIGO sensitivity band of 150 to 3000 Hz. We bound the rate for such detected bursts at less than 1.6 events per day at 90% confidence level. This result is interpreted in terms of the detection efficiency for ad hoc waveforms (Gaussians and sine-Gaussians) as a function of their root-sum-square strain h_{rss}; typical sensitivities lie in the range h_{rss} ~ 10^{-19} - 10^{-17} strain/rtHz, depending on waveform. We discuss improvements in the search method that will be applied to future science data from LIGO and other gravitational wave detectors.Comment: 21 pages, 15 figures, accepted by Phys Rev D. Fixed a few small typos and updated a few reference