371 research outputs found

    Effects of Dredge Material Placement on Macroinvertebrate Communities: Phase 1

    Get PDF
    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

    Get PDF
    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

    Get PDF
    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.

    Get PDF
    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

    Get PDF
    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

    Get PDF
    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

    Get PDF
    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 δM(Q,R)\delta M(Q,R) required to raise a tide on such a star, divided by the square of the tide's quadrupole moment QQ, is a decreasing function of the star's radius RR, (d/dR)[δM(Q,R)/Q2]<0(d/dR)[\delta M(Q,R)/Q^2]<0 (where, as RR changes, the star's structure is changed in accord with the star's fundamental mode of radial oscillation). If (d/dR)[δM(Q,R)/Q2](d/dR)[\delta M(Q,R)/Q^2] 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
    • …
    corecore