So the Yankees searched for answers about how this might be taking place, and on the evening of Aug. 18, the Yankees’ staff discovered in video review what it determined to be incontrovertible evidence -- as first detailed in the New York Times on Tuesday afternoon. An assistant trainer received a message on his watch; the trainer informed a Red Sox player in the dugout; the player relayed that information to the runner at second base, indicating which pitch signal in the sequence of signs was real; the runner at second, instantly armed with the key to breaking the Yankees’ signal-calling code, could detail the identity of the forthcoming pitch for the hitter at the plate.
Steroid isolation , depending on context, is the isolation of chemical matter required for chemical structure elucidation, derivitzation or degradation chemistry, biological testing, and other research needs (generally milligrams to grams, but often more  or the isolation of "analytical quantities" of the substance of interest (where the focus is on identifying and quantifying the substance (for example, in biological tissue or fluid). The amount isolated depends on the analytical method, but is generally less than one microgram.  [ page needed ] The methods of isolation to achieve the two scales of product are distinct, but include extraction , precipitation, adsorption , chromatography , and crystallization . In both cases, the isolated substance is purified to chemical homogeneity; combined separation and analytical methods, such as LC-MS , are chosen to be "orthogonal"—achieving their separations based on distinct modes of interaction between substance and isolating matrix—to detect a single species in the pure sample. Structure determination refers to the methods to determine the chemical structure of an isolated pure steroid, using an evolving array of chemical and physical methods which have included NMR and small-molecule crystallography .  : 10–19 Methods of analysis overlap both of the above areas, emphasizing analytical methods to determining if a steroid is present in a mixture and determining its quantity.