Degradative acetolactate synthase of Bacillus subtilis: purification and properties.

A degradative acetolactate synthase (acetolactate pyruvate-lyase [carboxylating], EC 4.1.3.

Alternatives to the design of manipulating a variable to compare retarded and nonretarded subjects.

In the design of manipulating a single variable to compare the performance of retarded and nonretarded subjects, the groups' response to the variable cannot demonstrate a loss of ability of retarded subjects. This is because tasks (measures at points on the variable) which differ on difficulty or on reliability also differ in power to distinguish subjects of differing ability. A solution is to hypothesize a differential deficit (greater deficit in response to one variable than another) and manipulate two variables.