Preparation and in vitro evaluation of GdDOTA-(BOM)4; a novel angiographic MRI contrast agent

A novel Gd(III) complex, GdDOTA-(BOM)4, has been prepared by a simple three-step procedure. The complex showed high T1-relaxivity values in serum albumin solutions, blood and plasma, resulting from high affinity for serum albumin. The T1-relaxivity in plasma, 67.4 s-1 mM-1 (20 MHz, 37 degrees C), makes it a promising candidate for angiographic applications of MRI.     

Kinetics of emulsion polymerization

The quantitative theory of the free-radical mechanism in emulsion polymerization is reexamined. A mechanism involving desorption and reabsorption of radicals is discussed. The average number of radicals per particle has been calculated as a function of three parameters. A simplified, approximate solution for the average number of radicals per particle is given for cases where this number is low.     

On the reduction of a symmetric matrix to tridiagonal form

A stable algorithm for reducing a symmetric, non-definite matrix of ordern to tridiagonal form, involving aboutn ³/6 additions and multiplications is presented.     

The relative stereochemistry of hyperforin - an antibiotic from hypericum perforatum L.

The relative stereochemistry of hyperforin, an antibiotic from $\text{Hyperium perforatum}$ has been determined by X-ray diffraction measurements.     

Synthesis of D-Ala--D-Ala analogues with postulated antibacterial activity

The syntheses of the L,L- and D,D-stereoisomers of N-phenoxyacetyl-X-alanine in which X=His, Tyr, or Lys, are described. The antibacterial activity of some of the peptide derivatives and their synthetic intermediates have been examined. Some of the intermediates exhibited moderate activity against viridans streptococci, enterococci and Streptococcus agalactiae. None of the compounds were active against beta-lactamase producing bacteria or served as beta-lactamase inhibitors.     

Steady-State Upscaling

Steady-state upscaling is based on steady-state solutions to the two-phase flow equations. We study features of steady-state solutions, and the applicability of upscaled flow functions based thereon in transient situations. Also, efficient computation of steady-state solutions is addressed: The existence of a class of problems is proved, where two-phase streamlines (in the viscous limit) are identical to streamlines in the corresponding one-phase problem.