The effect of tetrathionate on the stability and immunological properties of muscle triosephosphate dehydrogenases

Tetrathionate effect on stability and immunological properties of muscle triosephosphate dehydrogenase

The Valuation of Cash Flow Forecasts: An Empirical Analysis

This paper compares the market value of highly leveraged transactions (HLTs) to the discounted value of their corresponding cash flow forecasts. These forecasts are provided by management to investors and shareholders in 51 HLTs completed between 1983 and 1989. Our estimates of discounted cash flows are within 10%, on average, of the market values of the completed transactions. Our estimates perform at least as well as valuation methods using comparable companies and transactions. We also invert our analysis and estimate the risk premium implied by transaction values and forecast cash flows, and the relation of the implied risk premium to firm-level betas, industry-level betas, firm size, and firm book-to-market ratios.

A comparative study of the evolution of enzymes and nucleic acids Semiannual progress report, 1 May - 30 Nov. 1967

Immunological and enzymological approaches to evolution of enzymes and nucleic acid

Lattice formulation of (2,2) supersymmetric gauge theories with matter fields

We construct lattice actions for a variety of (2,2) supersymmetric gauge theories in two dimensions with matter fields interacting via a superpotential.Comment: 13 pages, 2 figures. Appendix added, references updated, typos fixe

Supersymmetry on a Spatial Lattice

We construct a variety of supersymmetric gauge theories on a spatial lattice, including N=4 supersymmetric Yang-Mills theory in 3+1 dimensions. Exact lattice supersymmetry greatly reduces or eliminates the need for fine tuning to arrive at the desired continuum limit in these examples.Comment: Version 3: Text brought in line with published version (extended discussion of orbifolding

Low-energy Mott-Hubbard excitations in LaMnO_3 probed by optical ellipsometry

We present a comprehensive ellipsometric study of an untwinned, nearly stoichiometric LaMnO_3 crystal in the spectral range 1.2-6.0 eV at temperatures 20 K < T < 300 K. The complex dielectric response along the b and c axes of the Pbnm orthorhombic unit cell, \epsilon^b(\nu) and \epsilon^c(\nu), is highly anisotropic over the spectral range covered in the experiment. The difference between \epsilon^b(\nu) and \epsilon^c(\nu) increases with decreasing temperature, and the gradual evolution observed in the paramagnetic state is strongly enhanced by the onset of A-type antiferromagnetic long-range order at T_N = 139.6 K. In addition to the temperature changes in the lowest-energy gap excitation at 2 eV, there are opposite changes observed at higher energy at 4 - 5 eV, appearing on a broad-band background due to the strongly dipole-allowed O 2p -- Mn 3d transition around the charge-transfer energy 4.7 eV. Based on the observation of a pronounced spectral-weight transfer between low- and high-energy features upon magnetic ordering, they are assigned to high-spin and low-spin intersite d^4d^4 - d^3d^5 transitions by Mn electrons. The anisotropy of the lowest-energy optical band and the spectral weight shifts induced by antiferromagnetic spin correlations are quantitatively described by an effective spin-orbital superexchange model. An analysis of the multiplet structure of the intersite transitions by Mn e_g electrons allowed us to estimate the effective intra-atomic Coulomb interaction, the Hund exchange coupling, and the Jahn-Teller splitting energy between e_g orbitals in LaMnO_3. This study identifies the lowest-energy optical transition at 2 eV as an intersite d-d transition, whose energy is substantially reduced compared to that obtained from the bare intra-atomic Coulomb interaction.Comment: 10 pages, 14 figure

Chiral 2π2\pi-exchange NN-potentials: Two-loop contributions

We calculate in heavy baryon chiral perturbation theory the local NN-potentials generated by the two-pion exchange diagrams at two-loop order. We give explicit expressions for the mass-spectra (or imaginary parts) of the corresponding isoscalar and isovector central, spin-spin and tensor NN-amplitudes. We find from two-loop two-pion exchange a sizeable isoscalar central repulsion which amounts to $62.3$MeV at $r=1.0$fm. There is a similarly strong isovector central attraction which however originates mainly from the third order low energy constants $\bar d_j$ entering the chiral $\pi N$-scattering amplitude. We also evaluate the one-loop $2\pi$-exchange diagram with two second order chiral $\pi \pi NN$-vertices proportional to the low energy constants $c_{1,2,3,4}$ as well as the first relativistic 1/M-correction to the $2\pi$-exchange diagrams with one such vertex. The diagrammatic results presented here are relevant components of the chiral NN-potential at next-to-next-to-next-to-leading order.Comment: 6 pages, 2 figure

The Delta-Delta Intermediate State in 1S0 Nucleon-Nucleon Scattering From Effective Field Theory

We examine the role of the Delta-Delta intermediate state in low energy NN scattering using effective field theory. Theories both with and without pions are discussed. They are regulated with dimensional regularization and MSbar subtraction. We find that the leading effects of the Delta-Delta state can be absorbed by a redefinition of the contact terms in a theory with nucleons only. It does not remove the requirement of a higher dimension operator to reproduce data out to moderate momentum. The explicit decoupling of the Delta-Delta state is shown for the theory without pions.Comment: 16 pages, 3 figures, uses harvma

Neutrino-Deuteron Scattering in Effective Field Theory at Next-to-Next-to Leading Order

We study the four channels associated with neutrino-deuteron breakup reactions at next-to-next to leading order in effective field theory. We find that the total cross-section is indeed converging for neutrino energies up to 20 MeV, and thus our calculations can provide constraints on theoretical uncertainties for the Sudbury Neutrino Observatory. We stress the importance of a direct experimental measurement to high precision in at least one channel, in order to fix an axial two-body counterterm.Comment: 32 pages, 14 figures (eps