Risk which is common to an entire class of assets or liabilities. The value of investments may decline over a given time period simply because of economic changes or other events that impact large portions of the market.
Properties of the alpha-helix. 1  The structure repeats itself every 5.4 Angstroms along the helix axis, ie we say that the alpha-helix has a pitch of 5.4 Angstroms. Alpha-helices have 3.6 amino acid residues per turn, ie a helix 36 amino acids long would form 10 turns.
double helix (Watson-Crick helix) the structure of deoxyribonucleic acid (DNA), consisting of two coiled chains, each of which contains information completely specifying the other chain.elix. 1. spiral (2). 2. the superior and posterior free margin of the pinna of the ear. Î±-helix, alpha helix the structural arrangement of parts of protein molecules in which a single polypeptide chain forms a right-handed helix stabilized by intrachain hydrogen bonds.