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         PASS gives you an opportunity to evaluate 
        the contribution of each atom of the structure to the estimation of 
        biological activity. You should select a type of biological activity at 
        the Activity Spectra Prediction or select it from the combo box, which 
        is above the structure representation. Pa (0.973) and Pi (0.003) values 
        for the selected activity are displayed over the structure. 
        The color of the atom depends from the 
        contribution of the atom to the activity.  
        
        Red – Pa = 0, Pi=1; (these structure elements are 
        not in compounds with the desired activity) 
        
        Green – Pa=1, Pi=0; (these structure elements are in 
        compounds with the desired activity) 
        
        Blue – Pa=0, Pi=0; 
        
        Grey – Pa=0.33, 
        Pi=0.33.  |