2,512 research outputs found
Evaluation of Ankom F58 Filter Bags Compared to Dacron Bags and Beakers for Analysis of Acid Detergent Fiber
Feed and fecal samples were analyzed to compare three methods of determining acid detergent fiber. Each sample was weighed into both Dacron and Ankom F58 fiber bags and then analyzed using an Ankom fiber analyzer. Results were then compared to the Van Soest beaker method. Ankom F58 bags helped reduce washout of small particles associated with Dacron bags, but fecal samples needed to be incubated in detergent for an extended amount of time to isolate acid detergent fiber material. Utilizing a technique that produces correct acid detergent fiber values is important for producers because these values are used as a proxy for calculating total digestible nutrients of feedstuffs
Constraining cosmological ultra-large scale structure using numerical relativity
Cosmic inflation, a period of accelerated expansion in the early universe,
can give rise to large amplitude ultra-large scale inhomogeneities on distance
scales comparable to or larger than the observable universe. The cosmic
microwave background (CMB) anisotropy on the largest angular scales is
sensitive to such inhomogeneities and can be used to constrain the presence of
ultra-large scale structure (ULSS). We numerically evolve nonlinear
inhomogeneities present at the beginning of inflation in full General
Relativity to assess the CMB quadrupole constraint on the amplitude of the
initial fluctuations and the size of the observable universe relative to a
length scale characterizing the ULSS. To obtain a statistically significant
number of simulations, we adopt a toy model in which inhomogeneities are
injected along a preferred direction. We compute the likelihood function for
the CMB quadrupole including both ULSS and the standard quantum fluctuations
produced during inflation. We compute the posterior given the observed CMB
quadrupole, finding that when including gravitational nonlinearities, ULSS
curvature perturbations of order unity are allowed by the data, even on length
scales not too much larger than the size of the observable universe. Our
results illustrate the utility and importance of numerical relativity for
constraining early universe cosmology.Comment: 14 pages, 6 figures v3: Clarifications added regarding the generality
of results - conclusions unchanged, version accepted for publication in PRD,
v2: updated with minor clarifications, submitte
Improvements in physics "Advanced Laboratory Courses"
Issued as Final project report, Project no. G-41-53
Evaluation of Protein Utilization in Low and High Protein Forage Sources and the Economic Value of Supplementing Field Peas (pisum sativum) to Growing Cattle Grazing Crested Wheatgrass Pastures
Field peas are widely grown in the panhandle of Nebraska; however, markets quickly become saturated. A two year experiment was conducted comparing field peas to dry distillers grains with solubles (DDGS) as a protein supplement. The objective was to establish a price producers could pay for field peas relative to DDGS. There was a significant difference in ADG due to type of supplement (P = 0.02). Field pea supplemented heifers had 10% lower ADG compared to DDGS supplemented heifers. Economically, this means if DDGS is priced at or 2.89/ 27 kg, for field peas.
Variable sources of grazed forages are used in cattle backgrounding systems, but in most systems metabolizable protein (MP) is limiting and rumen undegradable protein (RUP) supplement can meet this deficiency. The first objective was to determine if RUP is limiting and the second objective was to determine if highly digestible forages with rapid passage rate allow some rumen degradable protein (RDP) to bypass the rumen. A pooled analysis of growing cattle grazing forages demonstrated that average daily gain (ADG) increased with increased RUP supplement received, with the exception of animals grazing forages that were 17% crude protein (CP) or greater. A metabolism study evaluating high and low quality forages showed lower intakes and digestibility values for the lower quality forages. Rapid liquid passage rates suggest some degradable protein could be leaving the rumen before degradation. Numerous digestibility markers were used to evaluate markers in forage based diets.
Advisor: Andrea K. Watso
On Charge-3 Cyclic Monopoles
We determine the spectral curve of charge 3 BPS su(2) monopoles with C_3
cyclic symmetry. The symmetry means that the genus 4 spectral curve covers a
(Toda) spectral curve of genus 2. A well adapted homology basis is presented
enabling the theta functions and monopole data of the genus 4 curve to be given
in terms of genus 2 data. The Richelot correspondence, a generalization of the
arithmetic mean, is used to solve for this genus 2 curve. Results of other
approaches are compared.Comment: 34 pages, 16 figures. Revision: Abstract added and a few small
change
Dispersion of the high-energy phonon modes in NdCeCuO
The dispersion of the high-energy phonon modes in the electron doped
high-temperature superconductor NdCeCuO has been studied
by inelastic neutron scattering. The frequencies of phonon modes with Cu-O
bond-stretching character drop abruptly when going from the Brillouin zone
center along the [100]-direction; this dispersion is qualitatively similar to
observations in the hole-doped cuprates. We also find a softening of the
bond-stretching modes along the [110]-direction but which is weaker and
exhibits a sinusoidal dispersion. The phonon anomalies are discussed in
comparison to hole-doped cuprate superconductors and other metallic
perovskites
Origin and roles of a strong electron-phonon interaction in cuprate oxide superconductors
A strong electron-phonon interaction arises from the modulation of the
superexchange interaction by phonons. As is studied in Phys. Rev. B 70, 184514
(2004), Cu-O bond stretching modes can be soft around (pm pi/a, 0) and (0, pm
pi/a), with a the lattice constant of CuO_2 planes. In the critical region of
SDW, where antiferromagnetic spin fluctuations are developed around nesting
wave numbers Q of the Fermi surface, the stretching modes can also be soft
around 2Q. Almost symmetric energy dependences of the 2Q component of the
density of states, which are observed in the so called stripe and checker-board
states, cannot be explained by CDW with 2Q following the complete softening of
the 2Q modes, but they can be explained by a second-harmonic effect of SDW with
Q. The strong electron-phonon interaction can play no or only a minor role in
the occurrence of superconductivity.Comment: 5 pages, 1 fugur
Comparison blocks
"File: Human Relations, 3/79/5M""Playing with blocks is extremely important activity in the life of a preschool child. It is considered by educators to be one of the most important activities in which preschoolers can engage."--First paragraph.Ginny Braden (Area Child and Family Development Specialist), Marilyn C. Blossom (Child and Family Development Department Chairman
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