What Is an Automated External Defibrillator? An automated external defibrillator (AED) is a portable device that checks the heart rhythm and can send an electric shock to the heart to try to restore a normal rhythm. AEDs are used to treat sudden cardiac arrest (SCA). SCA is a condition in which the heart suddenly and unexpectedly stops beating.
curl. 1  to form into coils or ringlets, as the hair. 2  to form into a spiral or curved shape; coil. 3  to adorn with, or as with, curls or ringlets. 4  to grow in or form curls or ringlets, as the hair. 5  to become curved or undulated. 6  to coil. 7  to play at the game of curling.
Leaf curl, or leaf roll, is a natural response of the tomato plant to a sudden period of unusually warm weather. The leaf curl is a natural physiological response during hot weather. The plant senses that top growth has exceeded root growth, resulting in rolled leaves, which reduces growth until the roots catch up with the above ground growth.