WebZine
2018. 03
What's New
A New Wearable Brain Scanner
By Emily Waltz
In a design that looks straight out of an old future-tech horror film, researchers in the U.K. have built a wearable, portable brain scanner that can record neural activity while the user is moving.
The device, described today in Nature, could enable scientists to study brain function in ways that aren’t possible with stationary brain scanners, like that of functional magnetic resonance imaging, or fMRI.
“It’s a big step forward,” says Peter Schwindt, a physicist at Sandia National Laboratories in Albuquerque, N.M., who was not involved in the project. The technology “opens up new applications” for this type of brain scanning, he says.
That assumes people can get over the unfortunate look of the device, a wired-up head cast that falls somewhere between The Phantom of the Opera and Predator.
The device employs magnetoencephalography, or MEG, which measures magnetic fields present at the scalp. These fields are generated by the brain’s natural electrical currents, and, with mathematical analysis, can be used to create a 3D map of brain function with millisecond resolution.
Conventional MEG devices—cumbersome machines the size of a manatee—require the user to remain motionless while undergoing a scan, similar to the requirements of an fMRI. That severely limits the kinds of research that can be conducted. It also makes it difficult to study children.
In today’s report, researchers at the University of Nottingham and University College London, in the U.K., shrunk MEG to the size of gladiator helmet. The system would enable researchers to image people who find it hard to keep still, such as babies, children, and people with movement disorders.
The portable system would also allow scientists to conduct entirely new kinds of studies. “You can look at aspects of brain function involving spatial navigation, which is hard to do with a subject who is stationary,” says Richard Bowtell, a professor of physics at the University of Nottingham, who co-authored the report. “You can also look at more natural interactions between people when they are free to move.”
In the team’s design, the sensors are fixed relative to the person’s brain, rather than in a stationary machine. They achieved this by integrating miniaturized quantum sensors into a head cast, and pairing it with a system for canceling out background magnetic fields.
Origami-Folded Hydrogel Paper Instantly Generates 110 Volts of Electricity
By Christina Dabney
Posted 17 Mar 2018 | 13:00 GMT
Animal-inspired technology has gone electric. These brightly colored, 3D-printed gels have the potential to create up to 110 volts of electricity in an instant, similar to the electric eel.
Rows of small hydrogel dots are packed with positively and negatively charged ions that combine together to mimic an electric eel’s cellular structure. Printing and stacking these hydrogels produces the highest amount of voltage, while a connection to a larger contact area produces the highest current. Scientists are hoping that this system could potentially lead to a device that generates power from inside of the human body.
“The electric eel is able to create very, very large amounts of power. And we thought that this was remarkable,” said Anirvan Guha, one of the researchers on the project, designed at the University of Fribourg in Switzerland. “So we started to think about whether or not we could create a system that could generate electricity in the same way.”
An eel’s unique ability comes from a specialized organ housing thousands of cells called electrocytes. The chemical make up of these cells allows for a positive or negative charge. The surrounding membranes control the charge by allowing ions to pass through, inciting an electric reaction, or by blocking the ions and returning the organ to a neutral, dormant state.
When an eel is threatened or stalking prey, a neural impulse is sent to the membranes in the electrocytes, and positive ions flood into the cells. In a second, the electric voltage in each cell can go from zero millivolts to 150 millivolts, producing a total of up to 600 volts.
This new power generator works in a similar way.
It uses four different types of hydrogels to mimic the eel’s electrical system. One with a high salt concentration, one with a low salt concentration, and two charged membranes—one negative and one positive.
The first attempt at putting this system together involved using a fluidic autosampler that pushed the gels into sequence in tubes. The more gels in a sequence, the higher the voltage. But the researchers couldn’t build an array long enough to produce the desired voltage.