Surjectively rigid chains

Rigid Chains Admitting Many Embeddings

1. Abstract A chain (linearly ordered set) is rigid if it has no non-trivial automor-phisms. The construction of dense rigid chains was carried out by Dushnik and Miller for subsets of R, and there is a rather diierent construction of dense rigid chains of cardinality , an uncountable regular cardinal, using stationary sets as`codes', which was adapted by Droste in 1] to show the existence of r...

Permanently Linked Rigid Superparamagnetic Chains

Rigid DNA chains near nanoparticles

Two-photon excitation time-resolved fluorescence anisotropy and lifetime measurements were used to study the conformation of DNA near oppositely charged nanoparticles. Negatively-charged rhodamine-labeled DNA was allowed to adsorb onto positively-charged nanoparticles in deionized water and surface-induced fluorescence quenching was observed by measuring the fluorescence lifetime. Fluorescence ...

Single homopolypeptide chains collapse into mechanically rigid conformations.

Huntington's disease is linked to the insertion of glutamine (Q) in the protein huntingtin, resulting in polyglutamine (polyQ) expansions that self-associate to form aggregates. While polyQ aggregation has been the subject of intense study, a correspondingly thorough understanding of individual polyQ chains is lacking. Here we demonstrate a single molecule force-clamp technique that directly pr...

Kinematic Manipulation of Molecular Chains Subject to Rigid Constraint

We present algorithms for kinematic manipulation of molecular chains subject to fixed bond lengths and bond angles. They are useful for calculating conformations of a molecule subject to geometric constraints, such as those derived from two-dimensional NMR experiments. Other applications include searching out the full range of conformations available to a molecule such as cyclic configurations....