This is the series of blocks Amino acid substitution matrices (BLOSUM), all of which are derived based on direct on direct observation for every possible amino acid substitution in multiple sequence alignments.
A volt-ampere (VA) is the unit used for the apparent power in an electrical circuit, equal to the product of root-mean-square (RMS) voltage and RMS current.[1] In direct current (DC) circuits, this product is equal to the real power (active power) [2] in watts.
In a DC circuit, 1 VA is the equivalent of one watt (1 W). The power, P (in watts) in a DC circuit is equal to the product of the voltage V (in volt s) and the current I (in ampere s): P = VI. In an AC circuit, power and VA mean the same thing only when there is no reactance. Reactance is introduced when a circuit contains an inductor or capacitor.