The image accompanying the article "Getting to the root of the solution" on page 24 of the February issue included an incorrect caption. The caption should have read: "Infrared spectroscopy was used to map the functional groups in sunflower root tissue. The root section studied is in the blue rectangle in the visible image, while the intensity of infrared spectral bands versus location is plotted beside them. The images illustrate the distribution and concentration of lignin (top) and of protein (bottom), with spectral peaks at 845 and 1650 cm^–1, respectively."

In the article "The balance of success in cancer diagnosis" on page 50 of the March issue, the CCD camera manufacturer was misidentified. It should read as Apogee Instruments Inc. of Roseville, Calif.