Issues

Cover picture: An average (n = 150) cardiac myocyte Ca²⁺ spark in “4-D.” Each row shows 2-D images (x − y) at three vertical (z) positions separated by 1 μm; each column shows the spark at different times, separated by an interval of 5.6 ms. During the rise time (first four rows), the right-most image is the largest, as it was acquired last. The opposite is true during the decay phase. This feature was used to establish that each spark used in the average was in focus (see article by Shkryl et al., 189–207).