Dr. Elizabeth Sterling has a federal grant to develop an enzymatic method of isolating the epithelial cells that line the pancreatic duct. She has been working on this project for almost a year and must submit a report describing progress on the study. With the assistance of Jim Wong, a Ph.D. candidate in her lab, she is poring over photographs of isolated epithelial cells that she might include in the report. To Jim's eye, the photographs are of approximately equal contrast and quality, but some suggest more than others a greater yield of cells. Readouts from the automated cell counter, however, indicate that the yields have been fairly consistent.
Dr. Sterling instructs Jim to gather up four specific photos out of the ten that they have produced. These four photos will be included in the report, which Jim will help prepare. The photos, which Dr. Sterling says she has selected for their aesthetic quality, also happen to be the most supportive of the cell counter results. In the report, the photos will serve to illustrate the effectiveness and yield of Dr. Sterling's technique.