A saw includes a rotatable cutting blade having a first side, a second side, an outer edge and a front end region, a motor for driving the cutting blade, and a blade guard covering at least a portion of the blade. The invention also provides vectors, host cells, selective binding agents, and methods for producing C3bC4b CR-like polypeptides. The feeder serially feeds the envelopes to a cutter that severs the top edge of the envelopes. Further, a control is configured and arranged to drive the displacement of the cable transport arrangement. Further, a method for removing carpet comprising: the apparatus for removing carpet; moving the apparatus into position; engaging carpet to be removed with the carpet gripping means; and utilizing the hoist and resilient line to pull the carpet gripping means in order to remove the carpet. The system may minimize the incidence of stroke, myocardial infarction or other clinical complications that may be associated with cardiopulmonary bypass procedures.