Z. Naturforsch. 51 a, 1113-1122 (1996); eingegangen am 6. September 1996 After calculating ground and excited states of one-electron systems with improved discretization methods in Part III of this work it is shown that also correlation contributions can be yielded by this formalism. The more powerful discretization methods are applied to the two-electron systems He and H^. For multi-electron s...

We present an analysis of Chandra observations of two high-redshift clusters of galaxies, ClJ1113.1−2615 at z = 0.725 and ClJ0152.7−1357 at z = 0.833. We find ClJ1113.1−2615 to be morphologically relaxed with a temperature of kT = 4.3 −0.4 keV and a mass (within the virial radius) of 4.3 −0.7 × 10 M⊙. ClJ0152.7−1357, by contrast, is resolved into a northern and southern subcluster, each massive...

A molecular mechanics parameter set for the nitroxyl spin-label 3-formyl-2,2,5,5-tetramethyl-1-oxypyrroline was developed by application of Gaussian94 at the HF/6-31G(d) level suitable for use in molecular dynamics simulations. The parameter set was validated through molecular dynamics calculations for the methyl ester of N-(2,2,5,5-tetramethyl-1-oxypyrrolinyl-3carboxyl)-L-tryptophan to simulat...

The trifunctional flavoprotein proline utilization A (PutA) links metabolism and gene regulation in Gram-negative bacteria by catalyzing the two-step oxidation of proline to glutamate and repressing transcription of the proline utilization regulon. Small-angle x-ray scattering (SAXS) and domain deletion analysis were used to obtain solution structural information for the 1320-residue PutA from ...

We report the discovery of two spectroscopic binaries in the field of the old open cluster M67 – S 1063 and S 1113 – whose positions in the color-magnitude diagram place them ≈ 1 mag below the subgiant branch. A ROSAT study of M67 independently discovered these stars to be X-ray sources. Both have propermotion membership probabilities greater than 97%; precise center-of-mass velocities are cons...