Smooth Sailing with No Fuel
If you are traveling to the U.S. Virgin Islands in the next few months, you might glimpse the latest in robotic boats—an unmanned "green" submersible that exploits heat variations in ocean waters to glide under and through the waves. Developed by Woods Hole Oceanographic Institution and Webb Research, the vessel will be traversing the waters between St. Thomas and St. Croix for the next six months.
Dubbed a thermal glider, the craft doesn't require a fuel-burning motor. Instead, it slowly bobs up and down while its wings, tail fin, and rudder steer it forward on a zigzagging path. In the warm waters at the ocean's surface the glider captures and stores heat energy. Then, as it sinks into deeper, cooler water, it uses the energy to push oil from a "bladder" inside the hull to another one on the outside, changing the vessel's buoyancy and causing it to rise. Only onboard electronics such as navigation gear need extra power from alkaline batteries. Woods Hole hopes to use a fleet of such gliders to assess the ocean's response to climate change.
Can Breast Cancer Be Detected with Hair Follicles?
Mammograms are far from an ideal way to detect breast cancer. They are uncomfortable, miss tumors about 10% of the time, and frequently "find" tumors that don't exist. An Australian company hopes to solve some of these problems by examining not the breast, but hair follicles.
Sydney-based Fermiscan has built its diagnostic test upon a discovery that breast tumors can cause minute changes in the structure of a woman's hair. Those changes, Fermiscan believes, can be detected by examining light diffracted from the follicle. The company is now testing the theory in a 2,000-patient trial. It sends hair gathered from doctors' offices to Argonne National Laboratory in Argonne, Ill., where the follicles are analyzed using powerful X-ray beams from a large particle accelerator.
Fermiscan claims earlier tests have shown its method to be 80% accurate. But other scientists have yet to duplicate its results. What's more, the company acknowledges that its method cannot detect which breast is cancerous. "We're not trying to rule out mammograms," says David Young, Fermiscan's managing director. "We can complement them."
Pacemakers for Blood Pressure
About 25% of the 72 million Americans with hypertension either can't be helped by medication or don't take the pills they're prescribed. That leaves them at high risk of suffering strokes, heart attacks, and kidney failure. CVRx, a Minneapolis startup, has come up with a novel approach to helping such people: a pacemaker-like device that stimulates the body's own ability to regulate blood pressure.
The company's Rheos System, about the size of a deck of cards, is implanted under the skin near the collarbone, with electrodes extending to the carotid artery in the neck. Once activated by the surgeon, the device sends out electrical signals that trick the brain into thinking blood pressure is rising; the brain then directs the body's natural controls to bring pressure back to normal. The system was approved in Europe in October, and CVRx has just started an 18-month, 300-patient trial in the U.S.