caltech

Researchers at the California Institute of Technology say they have built what they call the world's first artificial neural network out of DNA molecules and that it can answer questions correctly.

Postdoctoral scholar Lulu Qian and colleagues describe "how molecular systems can exhibit autonomous brain-like behaviors" in a paper published about their research in the July 21 issue of the journal Nature.

Taking their cue from the limited intelligence exhibited by single-celled organisms, the researchers built four neurons made up of 112 distinct DNA strands (by contrast, the human brain has some 100 billion neurons).

This rudimentary … Read more

The California Institute of Technology is joining forces with France's CEA-Leti on a new initiative geared toward speeding delivery of nanotechnology systems and equipment from the lab to the business world.

The partnership will focus on several areas of nanotechnology systems, including high-sensitivity gas-phase chemical-sensing systems; highly multiplexed, microfluidic-interfaced mass spectrometry; and liquid-phase biochemical sensors for pharmaceutical research and point-of-care diagnostics.

Nanosystems are used to design microscopic, atomically precise structures and objects and are employed for a variety of applications and industries, from wireless devices to biology to health care.

CEA contributes to the nanotechnolgy field in four main … Read more

Researchers at Caltech have developed a mobile, four-wheeled robot that could help refine artificial retinas and other prostheses used by the visually impaired.

At first glance, Cyclops resembles a bot you might find on the battlefield, and it's hard to imagine what connection it could have to restoring sight. But dig a little deeper and it starts to make sense that a remote-controlled robot with an onboard camera could deliver some very useful data.

The digital camera can emulate left-to-right and up-and-down head movements. The idea is that as artificial vision prostheses increasingly become a reality, scientists could use the mobile robotic platform to mimic those devices--and more importantly, to get a better sense of how well they work for people who wear them.

The researchers might do that by asking the robot outfitted with an artificial vision aid to navigate obstacles in a corridor or follow a black line down a white-tiled hallway to see if it can find--and enter--a darkened doorway. All the while, they could try out different pixel arrays (say 50 pixels vs. 16 pixels), as well as image filters (for factors such as contrast, brightness enhancement, and grayscale equalization) to venture an educated guess as to what settings maximize a subject's sight.

But "we're not quite at that stage yet," researcher Wolfgang Fink says of such independent maneuvering. Fink is a visiting associate in physics at Caltech in Pasadena, Calif., and founder of the school's Visual and Autonomous Exploration Systems Research Laboratory, where where he and Caltech visiting scientist Mark Tarbell are collaborating on Cyclops with the support of a grant from the National Science Foundation.

The pair designed and built the body of the battery-operated rover using off-the-shelf parts, then furnished it with an onboard computing platform that allows for processing and manipulating images in real time using software they created called "Artificial Vision Support System."

Cyclops, so named because it's monocular, is about 12 inches wide by 12 inches long and 10 inches tall (the camera can be mounted on a mast to make Cyclops the height of an average person). It weighs about 15 pounds, Fink estimates, and can move at an "expedited walking speed" of about 2 to 3 feet per second.

For now, the platform itself is controlled remotely, via a joystick, and can be operated through a wireless Internet connection. "We have the image-processing algorithms running locally on the robot's platform," Fink says, "but we have to get it to the point where it has complete control of its own responses."

Once that's done, he adds, "we can run many, many tests without bothering the blind prosthesis carriers."… Read more

Researchers have come up with a microscopic microscope, tiny enough to fit on a fingertip, that can be cheaply mass-produced and used to scan blood and water for pathogens.

The high-resolution microscope functions without the large and expensive lenses usually associated with such imaging devices. Instead, it combines the chip technology found in digital cameras with "microfluidics," the science of channeling liquid at scales far smaller than a common droplet.

"The whole thing is truly compact--it could be put in a cell phone--and it can use just sunlight for illumination, which makes it very appealing for third-world applications," said Changhuei Yang, an assistant professor of electrical engineering and bioengineering at the California Institute of Technology and one of the lead developers of the device.

Yang imagines a range of uses for the so-called optofluidic microscope, which measures about the size of George Washington's nose on a quarter and has the magnifying power of a top-quality optical microscope, according to the Caltech research team.

Health field workers could use it to examine blood samples for malaria and check water for giardia and other parasites. It could be employed on the battlefield. Yang said the microscope could one day even be implanted inside humans to isolate rogue cancer cells circulating in the bloodstream.

"Our research is motivated by the fact that microscopes have been around since the 16th century, and yet their basic design has undergone very little change and has proven prohibitively expensive to miniaturize," said Yang, who is currently in talks with biotech companies about mass-producing the chip, a process he says costs about $10 per microscope. … Read more