These phenomenologically extracted work functions may be slightly different from the thermodynamic definition given above. However, studies since confirm that bipolar II is a "phenomenologically" distinct disorder. Thus, the influence of the extrinsic effects on the PL is usually addressed phenomenologically. Originally, the roton spectrum was phenomenologically introduced by Lev Landau. There are several large categories of bacteriocin which are only phenomenologically related. Historically, the task of describing the nuclear force phenomenologically was formidable. Jesus has to be phenomenologically defined, "before" his existence can be denied. His research program is a phenomenologically guided blend of two areas&colon; dreaming and literary reading. By contrast, the Meyerian perspective is phenomenologically oriented.