The tiniest chest movements, caused by breathing and even the beating of the heart, can be monitored using Doppler radar. Just like road-speed radar systems, this works by bouncing a radio wave off the chest and measuring any change in frequency caused by chest movement.
In theory, the technique could be very useful since it allows a patient to be monitored from a distance without fitting them with ECG leads. It can even record a heartrate through a person's clothing. But the signals can be easily swamped by noise caused by small movements of the patient or of other people around them, for example in a busy hospital ward.
Now Olga Boric-Lubecke, an electrical engineer at the University of Hawaii, US, has found a way to solve such problems.
She and colleagues have developed a radar device with several transmitters and receiving antennas that produce multiple signals that can be picked up and processed in a way that removes any random noise from other sources of movement.
The resulting signals are analysed by a computer to tease apart the various movements of a patient, including their heart beat and breathing pattern.
Read the full heart beat radar patent application.
Breathable hazard suit
The rubbery material used to make chemical protection suits gives good protection against toxic substances, but can make the wearer hot, sweaty, and extremely uncomfortable. That ultimately limits how long they can be worn.
Now Yossef Elabd at Drexel University in Philadelphia, US, has developed a "breathable" material that could do the job instead.
The material is a new class of polymer membrane incorporating nanopores filled with an ionic polymer that allows water vapour to pass through - this makes the suit breathable and more comfortable to wear.
However, if there is a risk of exposure to toxic substances, the nanopores can be closed by applying an electric field through the material. It is like an electrically controlled chemical valve that ensures nothing can get through.
The result is a mechanically strong, durable, flexible barrier that is breathable when required, and should make for far more comfortable protective clothing that can be worn for longer.
Read the full switchable protective clothing patent application.
Clinton Rubin and colleagues at the State University of New York in Stony Brook claim to have made the extraordinary discovery that vibrations can prevent and even reduce the formation of fat tissue.
Rubin says his research indicates that this occurs, not because the shaking increases the patient's metabolism as exercise would, but because it slows the formation of fat cells in the body in the first place.
The therapy could reduce obesity and prevent the onset of related problems such as diabetes, he says.
Rubin suggests that the subject could stand on a ground-based platform similar to weighing scales to receive the vibrations, or they could be delivered by vibrating shoes, or clothing.
Rubin and colleagues' work on mice has been published (read our story on the research here), and it will be interesting to see if the work makes it as far as human trials.
Read the full weight-loss device patent application.
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