The invention describes compounds, compositions, and methods of using the same comprising a chemical moiety covalently attached to amphetamine. However, WF fails to properly describe the behavior of the genetic pattern search algorithms due to some over-simplifications in their models. If the first segment length is not within the permitted range, a first error signal is issued, preferably indicating the non-complying first length. The present invention also is directed to a method of designing, synthesizing and identifying inhibitors of Sar A function and its role in the expression of staphylococcal virulence factors. The refractive index of the upper ELK dielectric layer is greater than the refractive index of the lower ELK dielectric layer.