Tiny waves could build livers on a 'liquid template' - tech - 04 July 2014 - New Scientist

Tiny waves could build livers on a 'liquid template' - tech - 04 July 2014 - New Scientist: After adding a handful of starter pieces, such as silicon chips or small plastic beads, the researchers tuned the generator to various frequencies to create waves in the solution. Depending on their surface chemistry, the added particles spontaneously collected in either the crests or the valleys. Retuning the generator let the team switch between multiple patterns...

He and his colleagues cultured mouse cells and put them in the liquid template. The cells collected into little spheres that became the building blocks of larger geometric patterns. Adding blood clotting proteins to the saline solution locked the cells in place, an approach that the team is now investigating for growing liver tissue.

Light Could Restore Lost Hearing - Scientific American

Light Could Restore Lost Hearing - Scientific American: In a study that appeared in March in the Journal of Clinical Investigation, the researchers used viruses to implant genes for light sensitivity into mouse embryos of a deaf lineage. The genes went to work in the auditory pathways of the mouse brains, creating light-sensitive patches on the membranes of their spiral ganglion neurons and other neurons. The scientists then directed LED light onto these neurons and recorded brain stem activity—an essential integration step in auditory processing.

Spinning Yarn Into Muscles | Science/AAAS | News

Spinning Yarn Into Muscles | Science/AAAS | News: Baughman, along with colleagues in Texas, Australia, and China, twisted plastic fibers and threads into yarns. Then when they applied heat, they found that the yarns contracted by up to 50%, a result they report today in Science. And cooling the plastic muscles returns them to their original length. Natural muscles, by comparison, only contract by 20%. Twisting together a bundle of polyethylene fishing lines, whose total diameter is only about 10 times larger than a human hair, produces a coiled polymer muscle that can lift 7.2 kilograms, the team found. Operated in parallel, an arrangement that increases their power and is similar to the way natural muscles are configured, a hundred of these polymer muscles could lift about 725 kilograms, Baughman says. Producing this force requires only off-the-shelf materials that cost about $5 per kilogram.

A Micro-Muscular Break Through � Berkeley Lab News Center

A Micro-Muscular Break Through � Berkeley Lab News Center: ...a micro-sized robotic torsional muscle/motor made from vanadium dioxide that for its size is a thousand times more powerful than a human muscle, able to catapult objects 50 times heavier than itself over a distance five times its length within 60 milliseconds...

Wu and his colleagues fabricated their micro-muscle on a silicon substrate from a long “V-shaped” bimorph ribbon comprised of chromium and vanadium dioxide. When the V-shaped ribbon is released from the substrate it forms a helix consisting of a dual coil that is connected at either end to chromium electrode pads. Heating the dual coil actuates it, turning it into either a micro-catapult, in which an object held in the coil is hurled when the coil is actuated, or a proximity sensor, in which the remote sensing of an object (meaning without touching it) causes a “micro-explosion,” a rapid change in the micro-muscle’s resistance and shape that pushes the object away...

The vanadium dioxide micro-muscles demonstrated reversible  torsional motion over one million cycles with no degradation. They also showed a rotational speed of up to approximately 200,000 rpm, amplitude of 500 to 2,000 degrees per millimeters in length, and an energy power density up to approximately 39 kilowatts/kilogram.

Robotics first: Engineering team makes artificial muscles that can lift loads 80 times their weight

Robotics first: Engineering team makes artificial muscles that can lift loads 80 times their weight; In order to achieve this, Dr Koh and his team have used polymers which could be stretched over 10 times their original length. Translated scientifically, this means that these muscles have a strain displacement of 1,000 per cent.

Researcher controls colleague’s motions in 1st human brain-to-brain interface | UW Today

Researcher controls colleague’s motions in 1st human brain-to-brain interface | UW Today: ...Rao sat in his lab wearing a cap with electrodes hooked up to an electroencephalography machine, which reads electrical activity in the brain. Stocco was in his lab across campus wearing a purple swim cap marked with the stimulation site for the transcranial magnetic stimulation coil that was placed directly over his left motor cortex, which controls hand movement...
Rao looked at a computer screen and played a simple video game with his mind. When he was supposed to fire a cannon at a target, he imagined moving his right hand (being careful not to actually move his hand), causing a cursor to hit the “fire” button. Almost instantaneously, Stocco, who wore noise-canceling earbuds and wasn’t looking at a computer screen, involuntarily moved his right index finger to push the space bar on the keyboard in front of him, as if firing the cannon. Stocco compared the feeling of his hand moving involuntarily to that of a nervous tic.

Watch Lab-Grown Heart Tissue Beat On Its Own [Video] | Popular Science

Watch Lab-Grown Heart Tissue Beat On Its Own [Video] | Popular Science: Using various enzymes and special cleansing detergents, the researchers stripped a mouse heart of all its cells to create a scaffold for induced pluripotent stem cells (iPS cells), adult human cells that are reprogrammed to act like embryonic cells. They treated the iPS cells taken from a skin biopsy to become multipotential cardiovascular progenitor (MCP) cells, the precursor cells that can become any of the three types of cells found in the heart...
After a period of a few weeks, the human cells had repopulated the mouse heart, and it began beating at a rate of 40 to 50 beats per minute.

Robotic Skin Lights Up When Touched - Wired Science

Robotic Skin Lights Up When Touched - Wired Science Thinner than a sheet of paper, the skin is made from layers of plastic and a pressure-sensitive rubber. A conductive silver ink, organic LEDs, and thin-film transistors made from semiconductor-enriched carbon nanotubes are sandwiched between the layers. Applying pressure sends a signal through the rubber that ultimately turns on the LEDs, which light up in red, green, yellow or blue.

Air bubbles could be the secret to artificial skin

Air bubbles could be the secret to artificial skin: On a uniform elastomeric substrate, traction tests revealed the creation of micro-fissures in the metallic layer, which would eventually result in the rupture of the conducting network. But with foam substrates, these cracks only occurred above the air bubbles. "Between the bubbles, the metal remained intact. The conducting network is thus maintained and can function," she explains. "Our measurements showed that we could achieve a level of elasticity over 100% without disrupting the network. These metallic pathways built upon foam could thus be used as electrodes, sensors or interconnections for the electronic skin that we're developing."

Zinc Oxide Nanowires Transistors Can Be Sophisticated Pressure Sensors | MIT Technology Review

Zinc Oxide Nanowires Transistors Can Be Sophisticated Pressure Sensors | MIT Technology Review: In the new research, Wang’s group demonstrates nanoelectronics that offer at least a 15-fold enhancement in sensor density and spatial resolution compared to the previous approaches... The density, resolution, and sensitivity of the sensors, says Wang, is comparable to that of the skin of a human finger...

In Wang’s nanowire transistors, the gate traditionally used in electronics is eliminated. Instead, the current flowing through the nanowires is controlled by the electrical charge generated when strain or force applied is to the transistors.

Artificial muscle computer performs as a universal Turing machine

Artificial muscle computer performs as a universal Turing machine: The artificial muscle computer is modeled on Stephen Wolfram's "2, 3" Turing machine architecture, which is the simplest known universal Turing machine...


In its current version, the artificial muscle computer is very large (about 1 m3) and extremely slow (0.15 Hz).

Brown University creates first wireless, implanted brain-computer interface

Brown University creates first wireless, implanted brain-computer interface: Brown’s wireless BCI, fashioned out of hermetically sealed titanium, looks a lot like a pacemaker... Inside there’s a li-ion battery, an inductive (wireless) charging loop, a chip that digitizes the signals from your brain, and an antenna for transmitting those neural spikes to a nearby computer. The BCI is connected to a small chip with 100 electrodes protruding from it, which, in this study, was embedded in the somatosensory cortex or motor cortex. These 100 electrodes produce a lot of data, which the BCI transmits at 24Mbps over the 3.2 and 3.8GHz bands to a receiver that is one meter away. The BCI’s battery takes two hours to charge via wireless inductive charging, and then has enough juice to last for six hours of use.

One of the features that the Brown researchers seem most excited about is the device’s power consumption, which is just 100 milliwatts...

One Per Cent: Artificial muscle for soft robots can bend in sunlight

One Per Cent: Artificial muscle for soft robots can bend in sunlight: When hit with UV light at a wavelength of 365 nanometres it expands, bending and increasing in mass by taking on water. Visible light at a wavelength of 430 nm restores the muscle to its previous form. "The gel absorbs water like an expanding and contracting sponge," says Harada.

The muscles work via the interaction of two chemical compounds in the gel - azobendrine and cyclodextrin - which react differently under different light. The direction in which the gel bends can then be controlled by shining UV and visible light from various angles.

Wax-Filled Nanotubes Flex Their Muscles - ScienceNOW

Wax-Filled Nanotubes Flex Their Muscles - ScienceNOW: Scientists have designed a flexible, yarnlike artificial muscle that can also pack a punch. It can contract in 25 milliseconds—a fraction of the time it takes to blink an eye—and can generate power 85 times as great as a similarly sized human muscle...

...Baughman's team realized, if they could instead infuse a material into carbon nanotubes to control the contraction, they could do away with the electrolyte solution. The researchers came up with a simple design: They soaked nanofibers in wax and then twisted them into yarns. The arrangement of the carbon nanofibers in the yarns is similar to the fibers in a finger trap child's game in which attempting to pull your fingers out of a tube only tightens it more. In the case of the carbon nanofibers, the expansion of the integrated wax shortens the fibers. And the wax's volume can be changed by altering the temperature, either using external power sources or in response to the surrounding environment. The new muscles, the team reports online today in Science, can lift about 100,000 times their own weight—many times more than a natural human muscle fiber.

A Carbon Microthread That Makes Contact with the Mind

A Carbon Microthread That Makes Contact with the Mind:  Researchers have come up with what they call a “stealthy neural interface” made from a single carbon fiber and coated with chemicals to make it resistant to proteins in the brain.

The new microthread electrode, designed to pick up signals from a single neuron as it fires, is only about 7 micrometers in diameter. That is the thinnest yet developed, and about 100 times as thin as the conventional metal electrodes widely used to study animal brains...


 He cautions, however, that it could be difficult to insert such fine, flexible electrodes into brain tissue, and to secure them. Schwartz notes that recordings broke down in many of the animals studied.

A Brain Implant that Thinks

A Brain Implant that Thinks: The researchers used an array of electrodes to record the electrical activity of neurons in the prefrontal cortex of monkeys while they performed a memory task...
The five monkeys in the study were trained to play a matching game in which they were shown an image on a screen and then had to use hand movements to steer a cursor to that same image...
From their recordings in the prefrontal cortex, the research team extrapolated a mathematical model of the electrical activity of neurons involved in the movement decision...
In the new study, the model took multiple signals produced by the brain layer that integrates sensory information related to the task. It then extracted the relevant information to choose a particular movement. The implant can stimulate neurons in order to influence the decision to move the hand to select the correct image.

Man Walks With Aid of Brain-Controlled Robotic Legs

Man Walks With Aid of Brain-Controlled Robotic Legs: The new device... is controlled by electroencephalogram...
The test subject in the study wore such a cap while standing on a treadmill inside leg braces known as a “robotic gait orthosis.” The subject would imagine walking or standing, and the device was taught to associate each brain activity pattern with the appropriate action. Then, whenever those patterns were encountered, the braces would start or stop walking accordingly.
The researchers also measured leg muscle activity by electromyogram, or EMG, for three conditions: active walking (with the robotic braces powered off), cooperative walking (aided by the braces), and passive walking (with the leg braces making all the movements).

Researchers engineer light-activated skeletal muscle - MIT News Office

Researchers engineer light-activated skeletal muscle - MIT News Office: The group has genetically engineered muscle cells to flex in response to light, and is using the light-sensitive tissue to build highly articulated robots...
The researchers cultured such cells, or myoblasts, genetically modifying them to express a light-activated protein. The group fused myoblasts into long muscle fibers, then shone 20-millisecond pulses of blue light into the dish. They found that the genetically altered fibers responded in spatially specific ways: Small beams of light shone on just one fiber caused only that fiber to contract, while larger beams covering multiple fibers stimulated all those fibers to contract...

Company Aims to Cure Blindness with Optogenetics

Company Aims to Cure Blindness with Optogenetics: Retrosense is developing a treatment in which other cells in the retina could take the place of the rods and cones, cells which convert light into electrical signals. The company is targeting a group of neurons in the eye called ganglion cells. Normally, ganglion cells don't respond to light. Instead, they act as a conduit for electrical information sent from the retina's rods and cones...
Doctors would inject a non-disease causing virus into a patient's eye. The virus would carry the genetic information needed to produce the light-sensitive channel proteins in the ganglion cells. Normally, rods, cones, and other cells translate light information into a code of neuron-firing patterns that is then transmitted via the ganglion cells into the brain. Since Retrosense's therapy would bypass that information processing, it may require the brain to learn how to interpret the signals.

One Per Cent: Hairy sensors to give robots sensitive skin

One Per Cent: Hairy sensors to give robots sensitive skin: Similar to their organic counterparts, the 50-nanometre-wide hairs of Suh's device twist and bend against each other when an external force like a beating heart or a soft touch is applied.

The contact between the hairs generates an electrical current which the sensor identifies as specific changes in pressure, shear or torsion...

... It could detect the dynamic motion of a tiny water droplet bouncing on a hydrophobic plate and the physical force of a heartbeat....