Identification of partially disordered peptide intermediates through residue-specific NMR diffusion measurements

It is technically challenging to detect low-population partially disordered species that are in equilibrium with the folded and unfolded states. Residue-specific translational diffusion experiments measured by pulsed field gradient NMR have been used to detect the presence, and define the conformation, of such equilibrium intermediates. The experiment is demonstrated for equilibrium solutions of related triple helical peptides that model a small region of type I collagen with and without a mutation known to cause osteogenesis imperfecta. The data show that residue-specific diffusion coefficients of an interconverting trimer to monomer system can allow discrimination between a simple two-state model and more complex multistate models involving partially disordered intermediates.     

Bound states of three and four resonantly interacting particles

We present an exact diagrammatic approach for the problem of dimer-dimer scattering in 3D for dimers being a resonance bound state of two fermions in a spin-singlet state, with corresponding scattering length a _F . Applying this approach to the calculation of the dimmer-dimer scattering length a _B , we recover exactly the already known result a _B = 0.6 a _F . We use the developed approach to obtain new results in 2D for fermions and bosons. Namely, we calculate bound state energies for three bbb and four bbbb resonantly interacting bosons in 2D. For the case of resonance interaction between fermions and bosons, we exactly calculate bound state energies of the following complexes: two bosons plus one fermion bbf, two bosons plus two fermions bf↑bf↓, and three bosons plus one fermion bbbf.     

Trends in the ionicity in the average valence V materials

An ionicity scale is given for average valence V materials. The scale is derived via the methods of the Phillips spectroscopic theory.     

The influence of the microscopic structure of surfaces on the optical properties of metals

The review outlines the state-of-the-art in the field of studies on the optical properties of metal surfaces. The use of recent theory has been examined to explain the results obtained in certain individual experiments on the surface modulation spectroscopy, outer photoemission and the surface Raman effect. The dependence of the surface plasmon spectrum on the surface microscopic structure has been given special consideration. It has been shown how information about the electronic structure of a surface, and the effect of adsorption on this structure in particular, can be extracted from the optical measurement data.     

The QCD Pomeron with optimal renormalization

It is shown that the next-to-leading order (NLO) corrections to the QCD Pomeron intercept obtained from the Balitsky-Fadin-Kuraev-Lipatov (BFKL) equation, when evaluated in non-Abelian physical renormalization schemes with Brodsky-Lepage-Mackenzie (BLM) optimal scale setting, do not exhibit the serious problems encountered in the scheme. A striking feature of the NLO BFKL Pomeron intercept in the BLM approach is that it yields an important approximate conformal invariance. Pis’ma Zh. éksp. Teor. Fiz. 70, No. 3, 161–166 (10 August 1999) Published in English in the original Russian journal. Edited by Steve Torstveit.