Conformational analysis of bradykinin by annealed molecular dynamics and comparison to NMR-derived conformations

Conformational analysis of bradykinin (BK), a nonapeptide of the sequence RPPGFSPFR, was accomplished using annealed molecular dynamics (AMD) at 1000 K in BIOGRAF 2.2. One hundred anneal cycles produced 100 conformations over approximately 2000 ps. These conformations were compared to structures derived by nuclear magnetic resonance (NMR) methods for similar shape and energy. Energy minimization of relevant conformations using both BIOGRAF 2.2 and AMBER 3.0a revealed that the AMD-determined conformations are in the same energy range as the NMR-determined structures. Also, the shape of the relevant conformations appeared similar, suggesting that AMD is a good tool for the conformational analysis of small peptide ligands. © 1993 John Wiley & Sons, Inc.     

Verbandsisomorphismen endlicher auflösbarer Gruppen

Ohne ZusammenfassungHerrn Professor Dr.Reinhold Baer zum 70. Geburtstag     

Organometallic complex compounds,part 51. Ligand property controlled CO-insertion in nickel complexes: Separation of electronic and steric effects

Summary The influence of twenty phosphorus-containing ligands on the CO insertion with four-coordinated Ni¹¹ complexes as starting reagents is reported. Quantitative separation of the electronic and steric effects by a multilinear regression analysis (55% electronic and 45% steric influence) is presented together with a three dimensional representation. An increase in donor-capacity favours CO insertion and an increase in steric hindrance leads to a decrease in the fraction of the corresponding ketone.     

Oil-continuous microemulsions composed of hexane, water, and 2-propanol

On the basis of conductivity and centrifugation data and visual examination, ternary phase diagrams were prepared for systems composed of hexane, water, and 2-propanol. Certain ternary compositions were shown to be oil-continuous microemulsions, even though a soap or detergent was not present. Of a number of short-chain alcohols tested, only 2-propanol and 1-propanol could stabilize a microemulsified ternary solution. Addition of a small amount of hexadecyltrimethylammonium perchlorate to the ternary solutions produced only modest changes in the ternary phase diagram. However, in the presence of hexadecyltrimethylammonium salts, most short-chain alcohols containing less than eight carbons could stabilize an oil-continuous microemulsion.     

The capacity and equivocation of a transducer and a connection with Billingsley dimension

In this paper the study of a noiseless transducer with finite memory, begun by Conner [Ann. Math. Statist.41, No. 6 (1970)], is set forth. The uniqueness and the weak Bernoulli property of the maximal-output dynamical system are proved. A convergence theorem about equivocation, which is analogous to McMillan's theorem about entropy, is obtained. An application of this theorem yields a lower estimation of the Billingsley dimension of the ambiguity set of almost all output messages.