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D W Pierce

Publications and source records attributed to D W Pierce.

3 recordsLinked to original sources

Two-dimensional crystals of Escherichia coli RNA polymerase holoenzyme on positively charged lipid layers.

Escherichia coli RNA polymerase holoenzyme forms two-dimensional crystals when adsorbed to positively charged lipid layers at the air/water interface. Adsorption of the protein is driven by electrostatic interactions between the positively charged lipid surface and the polymerase molecule, which has a net negative charge. Crystallization is dependent on the adsorption and concentration of RNA polymerase on fluid lipid surfaces. Image analysis of electron micrographs of crystals in negative stain, which diffract to 30 A resolution, shows irregularly shaped protein densities about 100 x 160 A, consistent with the dimensions of single polymerase molecules.

DNA-Directed RNA Polymerases

Suicidal intent in self-injury.

The difficulties in measuring suicidal intent in cases of self-injury are discussed, and a scale is described to measure this intent. This scale has been used in 500 cases of self-injury. It is practical and reliable. Results show that the scores derived from it are closely related to the similar Beck Scale; they are also related to age, sex, social isolation method of self-injury, previous history of self-injury or of psychiatric treatment, physical health at the time of self-injury and alcohol abuse. These results are discussed with particular reference to suicide prediction and the future validation of the scale by long-term follow-up.

Adolescent