371 research outputs found
Effects of Dredge Material Placement on Macroinvertebrate Communities: Phase 1
ID: 8809; issued October 1, 1998INHS Technical Report prepared for Rock Island District, US Army Corps of Engineer
Saturable discrete vector solitons in one-dimensional photonic lattices
Localized vectorial modes, with equal frequencies and mutually orthogonal
polarizations, are investigated both analytically and experimentally in a
one-dimensional photonic lattice with saturable nonlinearity. It is shown that
these modes may span over many lattice elements and that energy transfer among
the two components is both phase and intensity dependent. The transverse
electrically polarized mode exhibits a single-hump structure and spreads in
cascades in saturation, while the transverse magnetically polarized mode
exhibits splitting into a two-hump structure. Experimentally such discrete
vector solitons are observed in lithium niobate lattices for both coherent and
mutually incoherent excitations.Comment: 4 pages, 5 figures (reduced for arXiv
Beam interactions in one-dimensional saturable waveguide arrays
The interaction between two parallel beams in one-dimensional discrete
saturable systems has been investigated using lithium niobate nonlinear
waveguide arrays. When the beams are separated by one channel and in-phase it
is possible to observe soliton fusion at low power levels. This new result is
confirmed numerically. By increasing the power, soliton-like propagation of
weakly-coupled beams occurs. When the beams are out-of-phase the most
interesting result is the existence of oscillations which resemble the recently
discovered Tamm oscillations.Comment: 5 pages, 6 figures, submitted to Phys. Rev.
Restoring Ureagenesis in Hepatocytes by CRISPR/Cas9-mediated Genomic Addition to Arginase-deficient Induced Pluripotent Stem Cells.
Urea cycle disorders are incurable enzymopathies that affect nitrogen metabolism and typically lead to hyperammonemia. Arginase deficiency results from a mutation in Arg1, the enzyme regulating the final step of ureagenesis and typically results in developmental disabilities, seizures, spastic diplegia, and sometimes death. Current medical treatments for urea cycle disorders are only marginally effective, and for proximal disorders, liver transplantation is effective but limited by graft availability. Advances in human induced pluripotent stem cell research has allowed for the genetic modification of stem cells for potential cellular replacement therapies. In this study, we demonstrate a universally-applicable CRISPR/Cas9-based strategy utilizing exon 1 of the hypoxanthine-guanine phosphoribosyltransferase locus to genetically modify and restore arginase activity, and thus ureagenesis, in genetically distinct patient-specific human induced pluripotent stem cells and hepatocyte-like derivatives. Successful strategies restoring gene function in patient-specific human induced pluripotent stem cells may advance applications of genetically modified cell therapy to treat urea cycle and other inborn errors of metabolism
Comparing a Modified Dry By-product to Dry Distillers Grains with Solubles in Growing Calf Diets
A growing trial was conducted to contrast a new by-product, Dakota Bran Cake (DBRAN), against dry distillers grains with solubles (DDGS) and evaluate the two by-products at two dietary inclusion levels on steer calf performance measurements. Diet treatments included 15% DBRAN, 30% DBRAN, 15% DDGS, and 30% DDGS, replacing a blend (70:30 ratio) of brome grass hay and alfalfa haylage (DM basis). Final BW, ADG, and DMI increased, while F:G decreased as the inclusion level for both of these by-products increased from 15 to 30% DM. DDGS significantly improved ADG and F:G compared to feeding DBRAN at both inclusion levels. Feeding DBRAN and DDGS in growing diets to steer calves improved performance at higher dietary inclusion levels, while DDGS tended to improve performance over DBRAN
Effect of Distillers Grains Composition and Level on Steers Consuming High-Quality Forage
An experiment was conducted to determine the effects of dried distillers grains (DDG) supplementation level and composition on growing steer performance and forage intake. Factors included DDG supplementation level (0.25, 0.50, 0.75 or 1.00% of BW), and DDG solubles level (0, 5.4, 14.5, 19.1, or 22.1% DM). Final BW improved, and forage intake decreased with increasing levels of DDG. An interaction between DDG supplementation level and solubles level was observed on ADG and F:G and was likely related to supplemental fat levels. Supplementation of forages with DDG improves performance while decreasing forage intake when fat levels are not too great
Tidal Stabilization of Rigidly Rotating, Fully Relativistic Neutron Stars
It is shown analytically that an external tidal gravitational field increases
the secular stability of a fully general relativistic, rigidly rotating neutron
star that is near marginal stability, protecting it against gravitational
collapse. This stabilization is shown to result from the simple fact that the
energy required to raise a tide on such a star, divided by the
square of the tide's quadrupole moment , is a decreasing function of the
star's radius , (where, as changes, the
star's structure is changed in accord with the star's fundamental mode of
radial oscillation). If were positive, the tidal
coupling would destabilize the star. As an application, a rigidly rotating,
marginally secularly stable neutron star in an inspiraling binary system will
be protected against secular collapse, and against dynamical collapse, by tidal
interaction with its companion. The ``local-asymptotic-rest-frame'' tools used
in the analysis are somewhat unusual and may be powerful in other studies of
neutron stars and black holes interacting with an external environment. As a
byproduct of the analysis, in an appendix the influence of tidal interactions
on mass-energy conservation is elucidated.Comment: Revtex, 10 pages, 2 figures; accepted for publication in Physical
Review D. Revisions: Appendix rewritten to clarify how, in Newtonian
gravitation theory, ambiguity in localization of energy makes interaction
energy ambiguous but leaves work done on star by tidal gravity unambiguous.
New footnote 1 and Refs. [11] and [19
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