Removal of abundant proteins from a sample enhances detection and resolution of less abundant proteins in the sample such as in two-dimensional gel electrophoresis. In one embodiment, heat from one or more heaters may be provided to at least a portion of the formation. Also provided by the invention are tissue cultures of the soybean variety A1024631 and the plants regenerated therefrom. In the first part of the punch cycle, the clamp closes down onto the web, and then the spinning cutting head contacts the web. In alternative forms, in addition to, or alternative to the steerable endless track units, the apparatus includes height adjustment means for adjusting the vertical spacing between the main body portion and the respective endless tracks; and control means configured to control the action of the height adjustment means.