The University of Texas Medical Branch at Galveston (UTMB) is in the top tier when it comes to robotic surgeries. But when UTMB’s doctors training to be surgeons performed robotic simulations side by side with video game-playing high school and college students, the young gamers actually beat them out. The results were presented at a conference on minimally invasive gynecology [pdf] in November.
Forensic scientists of the future may soon have a new tool at their disposal. Given a drop of blood, researchers in the Netherlands have roughly determined the age of the person it came from. But for now, it really is rough–the researchers found they could only estimate a person’s age to within 9 years.
Currently, a crime scene investigator who obtained a spot of blood can check its DNA to see if it matches a known suspect or someone in a law enforcement database, and can use the DNA to determine a few other characteristics like gender and eye color. But age is tougher to estimate. Lead researcher Manfred Kayser, who works on forensic molecular biology at Erasmus University Medical Centre, explains that the best methods of determining age rely on testing bones or teeth, but he wanted to find a method that didn’t require skeletal remains.
Devices that use the wasted mechanical energy from clothing movements or even a heartbeat seem far out, if not just a bit creepy, but new advances in nanogenerators are making such energy-scavenging electronics possible.
Now researchers at Georgia Tech have made the first nanowire-based generators that can harvest sufficient mechanical energy to power small devices, including light-emitting diodes and a liquid-crystal display. [Technology Review]
The new generators use materials that have a particularly odd property: They collect a charge and drive a current when flexed (this is called piezoelectricity). The problem in using these materials for energy-harvesting applications has been that the materials that were sufficiently efficient at driving a current were too rigid, and those that were flexible enough weren’t very efficient.
In an exciting pilot study, blind people equipped with microchips in their retinas were able to see again–at least dimly–and were able to make out shapes.
Ed Yong explains how the experiment helped a study participant named Miikka:
In people like Miikka with retinitis pigmentosa, the light-detecting cells of the retina break down with age. Eberhart Zrenner and a team of German scientists have designed a chip that does the same job as these defunct cells. Just a few millimetres across, it contains 1,500 light-detecting diodes that detect light and convert it into a current. The brighter the light that hits the chip, the stronger the current it puts out. The current is delivered directly to the bipolar cells, which would normally transmit the signals from the retina’s actual light detectors.
Find out more about how the technology works and get the full story on Miikka and his fellow experiment subjects at Not Exactly Rocket Science. And check out the videos of Miikka trying out his new eyes below.
Not Exactly Rocket Science: Retinal Implant Partially Restores Sight in Blind People
80beats: The Eyes Have It: Lab-Made Corneas Restore Vision
80beats: Stem Cell Treatment Lets Those With Scorched Corneas See Again
80beats: The Part of the Brain That Lets the Blind See Without Seeing
80beats: Gene Therapy Cures Color Blindness in Monkeys
Researchers have built miniature human livers in the lab, which could lead to better drug discovery and could even point the way toward implantable artificial organs. The mini-livers seem to act like human livers in the lab, but it remains to be seen how well they’ll survive and perform when transplanted into animals or, maybe one day, humans.
“We are excited about the possibilities this research represents, but must stress that we’re at an early stage and many technical hurdles must be overcome before it could benefit patients,” said Shay Soker, Ph.D., professor of regenerative medicine and project director. “Not only must we learn how to grow billions of liver cells at one time in order to engineer livers large enough for patients, but we must determine whether these organs are safe to use in patients.” [Press release].
The researchers at Wake Forest’s Institute for Regenerative Medicine created livers that weigh about 0.2 ounces each. That’s not nearly large enough to keep a human alive (it would need to be about 80 times larger for that), but getting the organ made was a feat in itself. The livers were made using the extracellular scaffolding from an animal liver, after all of the animal’s cells had been gently removed from it.
For DARPA, the secretive military research agency, it’s not enough for a prosthetic limb to simply resemble a normal one, or for a patient to be able to move it through some remote control. DARPA-backed engineers are attempting to build a system in which peripheral nerves would be reattached to artificial limbs, which could send signals to a brain sensor that could reply. This would be a vast improvement over prosthetics that require conscious directives, and could turn a prosthetic into something that responds the way an ordinary limb would.
Darpa’s after a prosthetic that can record motor-sensory signals right from peripheral nerves (those that are severed when a limb is lost) and then transmit responding feedback signals from the brain. That means an incredibly sensitive platform, “capable of detecting sufficiently strong motor-control signals and distinguishing them from sensory signals and other confounding signals,” in a region packed tightly with nerves. Once signals are detected, they’ll be decoded by algorithms and transmitted to the brain, where a user’s intended movements would be recoded and transmitted back to the prosthetic. [Wired.com]
According to the team behind the system at Johns Hopkins University’s Applied Physics Laboratory, tests on monkeys have shown that the primates have remarkable success controlling a prosthesis through a cortical chip implanted in their brains, and researchers have undertaken some human tests. What remains to be seen, though, is how much dexterity people can get through this process.
Flexible materials technology may just bring the next wave of trendy to the markets, in the form of glowing tattoos and T- shirts. Or the hot new tech could be used for its intended purpose: monitoring medical conditions.
This flexible light-emitting diode (LED) array uses many already existing materials and techniques to create a nano-sized, flexible patch of light. A team lead by John Rogers developed the array as a medical device; it could be implanted to serve as a readout for monitoring internal body conditions, like blood oxygenation or glucose levels, or it could turn on light-activated drugs.
“The applications we’re interested in mostly include interfaces with the human body,” says John Rogers…. For some biological applications, he adds, a conventional LED’s brightness, reliable operation and suitability for waterproof implementation make it a more attractive option than an organic LED. [Scientific American].
Each individual LED is a square that measures 2.5 micrometers thick (smaller than the diameter of your cells’ nucleus) and 100 micrometers on each side (the thickness of a coat of paint). Many of these LEDs can be printed together to form an array of light points connected by swirls of connective wire that give it additional flexibility. The substrate is flexible enough that it can be stretched and flexed up to 75 percent without losing function. The researchers described the technology in the journal Nature Materials.
Hugging someone standing up. Going on a hike. Making eye contact with someone at their level, instead of always being looked down upon. These are simple things that people stuck in wheelchairs don’t have a chance to experience in daily life.
Berkeley Bionics is giving those experiences back to paraplegics with the introduction of an exoskeleton suit called eLEGS–a battery powered, artificially intelligent, wearable outer skeleton that gives these people back their freedom. People wearing these devices won’t be a common sight just yet–a suit is currently priced at about $100,000 a pop, and they’ll only be available for use in clinics at first–but it’s an exciting step forward.
The person straps into an exoskeleton made of carbon fiber and steel, which weighs 45 pounds. Sensors in the legs convey their position to a control unit contained in a backpack, and the controller tells which joints to bend to create a natural gait. The user gives the suit commands using two high-tech crutches: pressure on both tells the motorized legs to stand up, pressure on one means to step with the opposite leg. The suit’s battery pack can power up to six hours of walking, and it can reach speeds above two miles per hour.
Amanda Boxtel, who was paralyzed from the waist down in a skiing accident 18 years ago, tried out the device and says she took to it quickly.
“Walking with eLEGs took some rewiring and relearning,” says Boxtel, “but my body has the muscle memory. And I learned to walk really fast.” [New Scientist]
The suit will be used in a clinical trials at select rehabilitation centers starting in early 2011, and its makers hope a commercial model won’t be too far behind. Berkeley Bionics wants to make a lighter, thinner, and cheaper model (hopefully closer to $50,000, Berkeley Bionics CEO Eythor Bender says) available for home use by 2013.
Hit the jump for more info, and a poignant video of several paralyzed people giving eLEGS a tryout.
Researchers have designed the first artificial kidney small enough to slip comfortably inside the human body, and they say the technological breakthrough could be an enormous benefit for people grappling with kidney disease. Modern medicine can keep patients alive if their kidneys fail via external dialysis machines that filter toxins from their blood, but it’s a grueling and imperfect process.
Patients must be tethered to machines at least three times a week for three to five hours at a stretch. Even then, a dialysis machine is only about 13 percent as effective as a functional kidney, and the five-year survival rate of patients on dialysis is just 33 to 35 percent. To restore health, patients need a kidney transplant, and there just aren’t enough donor organs to go around. In August, there were 85,000 patients on the U.S. waiting list for a kidney … while only 17,000 kidney transplants took place last year. [Technology Review]
Illness-inducing bacteria, meet nano-engineered cotton–and a quick death. Researchers have created a new “filter” that zaps bacteria with electric fields to clean drinking water. They say their system may find use in developing countries since it requires only a small amount of voltage (a couple of car batteries, a stationary bike, or a solar panel could do the job) and cleans water an estimated 80,000 times faster than traditional devices.
Instead of trapping bacteria in small pores like many slow-going traditional filters, the cotton and silver nanowire combo uses small electric currents running through the nanowires to kill the bacteria outright. In a paper to appear in the journal Nano Letters researchers say that 20 volts and 2.5 inches worth of the material killed 98 percent of Escherichia coli in the water they tested in their lab setup.