Muscle-powered bio-bots walk on command | News Bureau | University of Illinois

Muscle-powered bio-bots walk on command | News Bureau | University of Illinois: The new bio-bots are powered by a strip of skeletal muscle cells that can be triggered by an electric pulse...

“Skeletal muscles cells are very attractive because you can pace them using external signals,” Bashir said. “For example, you would use skeletal muscle when designing a device that you wanted to start functioning when it senses a chemical or when it received a certain signal. To us, it’s part of a design toolbox. We want to have different options that could be used by engineers to design these things.”

The design is inspired by the muscle-tendon-bone complex found in nature. There is a backbone of 3-D printed hydrogel, strong enough to give the bio-bot structure but flexible enough to bend like a joint. Two posts serve to anchor a strip of muscle to the backbone, like tendons attach muscle to bone, but the posts also act as feet for the bio-bot.

Magnetic charge crystals imaged in artificial spin ice

Magnetic charge crystals imaged in artificial spin ice: In the honeycomb pattern, where three magnetic poles intersect, a net charge of north or south is forced at each vertex. The magnetic "monopole charge" at each vertex influences the magnetic "charge" of the surrounding vertices. The team was able to image the crystalline structure of the magnetic charges using magnetic force microscopy...

The research team's new annealing protocol—heating the material to a high temperature where their magnetic polarity is suppressed (here, about 550 degrees Celsius)—allows the nanomagnets to flip their polarity and freely interact. As the material cools, the nanomagnets are ordered according to the interactions of their poles at the vertices...

"This work demonstrates a direction in condensed matter physics that is quite opposite to what has been done in the last sixty years or so," said Nisoli. "Instead of imagining an emergent theoretical description to model the behavior of a nature-given material and validating it indirectly, we engineer materials of desired emergent properties that can be visualized directly."

Peaceful matter-antimatter pairing looks more real

Peaceful matter-antimatter pairing looks more real: The first signs of these Majorana fermions came last year in the form of a current that appeared at zero voltage in a nano-size wire...
They created a similar set-up but this time ramped the voltage up and down and shortened the wire. The plan was to cause the quantum waves associated with each fermion to overlap and constructively interfere, creating two extra peaks in current. Sure enough, the team saw two more blips...

Sandia seeks better neural control of prosthetics for amputees – Sandia Labs News Releases

Sandia seeks better neural control of prosthetics for amputees – Sandia Labs News Releases: Sandia’s research focuses on biomaterials and peripheral nerves at the interface site. The idea is to match material properties to nerve fibers with flexible, conductive materials that are biocompatible so they can integrate with nerve bundles...
The challenges are numerous. Interfaces must be structured so nerve fibers can grow through. They must be mechanically compatible so they don’t harm the nervous system or surrounding tissues, and biocompatible to integrate with tissue and promote nerve fiber growth. They also must incorporate conductivity to allow electrode sites to connect with external circuitry, and electrical properties must be tuned to transmit neural signals...
...Sandia researchers worked with polymers that are liquid at room temperature. Electrospinning these liquid polymers does not result in fiber formation, and the results are sort of like water pooling on a flat surface. To remedy the lack of fiber formation, they electrospun the material onto a heated plate, initiating a chemical reaction to crosslink the polymer fibers as they were formed, Dirk said.
Researchers were able to tune the conductivity of the final composite with the addition of multiwalled carbon nanotubes...
The team’s search for a different technique to create the porous substrates led to projection microstereolithography, developed at the University of Illinois Urbana-Champaign as an inexpensive classroom outreach tool. It couples a computer with a PowerPoint image to a projector whose lens is focused on a mirror that reflects into a beaker containing a solution.

'Electronic Skin' Grafts Gadgets to Body - ScienceNOW

'Electronic Skin' Grafts Gadgets to Body - ScienceNOW: Now, Rogers and his colleagues at Urbana-Champaign and other institutions in the United States, Singapore, and China have come up with a form of electronics that almost precisely matches skin's mechanical properties. Known as epidermal electronics, they can be applied in a similar way to a temporary tattoo: you simply place it on your skin and rub it on with water...
In one experiment, the group applied a device the size of a postage stamp to a person's chest to pick up the electrical signals produced by the heart. The measurements agreed "remarkably well" with those produced by a hospital electrocardiogram, the researchers say, without relying on potentially uncomfortable gels or tape. In another experiment, the group applied a device containing a microphone to a person's throat and fed the signal to a computer. The computer could recognize four different words: "up," "down," "left," and "right."

Cloud lasers: Hunting quantum secrets in the skies - environment - 30 November 2010 - New Scientist

Cloud lasers: Hunting quantum secrets in the skies: He thinks that a beam of infrared photons at precisely the right wavelength could stimulate emission from moisture in the air and trigger cloud formation. It's not the clouds themselves he is interested in, though: his idea is to harness the energy locked up in moist air. The trick, he says, would be to set up a pair of parallel mirrors with a constant supply of cool, moist air flowing between them. Shining a beam of infrared photons into this space should trigger the formation of water droplets, releasing more infrared radiation in the process.

If the mirrors are carefully aligned, the radiation should bounce back and forth through the moist air, stimulating even more emission. Tatartchenko says this will amplify the incoming beam. In other words, it will create a sort of cloud laser. By extracting a little of the beam - perhaps by making one mirror slightly transparent, as in a regular laser - he suggests that such a device could be used to generate usable energy.

Light-harvesting Complexes Do It Themselves - Science News

Light-harvesting Complexes Do It Themselves - Science News: The researchers began with light-harvesting reaction centers from a purple bacterium. Then they added some proteins and lipids for structure, and carbon nanotubes to conduct the resulting electricity.

These ingredients were added to a water-filled dialysis bag — the kind used to filter the blood of someone whose kidneys don’t work — which has a membrane that only small molecules can pass through. The soupy solution also contained sodium cholate, a surfactant to keep all the ingredients from sticking together.

When the team filtered the surfactant out of the mix, the ingredients self-assembled into a unit, capturing light and generating an electric current.