Miniaturization of available technology holds the key to many of the medical advances of the future, Dr. Stephen C. Jacobsen believes.

A 500-micron Wobble motor (about the width of five human hairs) developed in the Center for Engineering Design, University of Utah, is an example of such miniaturization, said Jacobsen, who heads the center. It is a product of the Micro Electro Mechanical System being pursued by scientists at the center.The center has approximately $7 million in grants to develop "micro things," Jacobsen said - a "major new direction - a generic change in technology" that has implications for such fields as optics, microsurgery and prosthetics. A miniature electronic "lab in a chip" that could be inserted into the body temporarily to measure and monitor chemicals could become the ultimate disposable of 21st century medicine.

Tiny dexterity machines at the end of catheters may become an extension for the surgeon's fingers, reaching into places and performing tasks the surgeon could not.

The Utah Arm, a device activated by electricity generated by the residual muscle of an amputee, was developed at the University of Utah over a period of several years. It is being marketed worldwide, with about 500 now in use, Jacobsen said.

The Utah/MIT Dextrous Hand has been developed in the Utah center in cooperation with MIT. Initially, the research will simply help scientists understand the complex functioning of the human hand. The present prototype hands are simply "for research to study machine dexterity. We didn't even know what the hand can do."

In the end, Jacobsen concludes, "Biology is a hard act to follow." Scientists may never be able to replicate some of the body's functions.