Tuesday, 28 February 2012

New Neural Interfaces Can Bring True Feeling to Artificial Limbs



Future Prosthetic Limbs Robotics engineer Steve Buerger displays implantable and wearable neural interface electronics developed by Sandia as he sits in the prosthetics lab with a display of prosthetic components. He is part of a research team that is working on ways to improve amputees’ control over prosthetics with direct help from their own nervous system. Sandia National Laboratories/Randy Montoya
New plastic scaffolds attached to prosthetic devices could enable nerves to feel and control artificial limbs, using electrical signals to bring back real sensations. The research could eventually realize the dream of connecting artificial body extensions to the living nervous system.
Despite major advances in prosthetics, researchers have not been able to fully integrate nerves and prosthetic devices — though several teams, including DARPA, have been trying. New research at Sandia National Laboratories, the University of New Mexico and MD Anderson Cancer Center in Houston could make it a reality.
Connecting mechanical instruments to human nerves is complex on several levels because the interface would need to share several special properties between man and machine. It would have to be biocompatible to promote nerve and tissue growth, but mechanically compatible to allow electrodes to connect to external circuits. It would have to be structured to avoid harming surrounding tissue, but it would have to work in concert with that tissue to serve as a real replacement limb.
New biocompatible interface scaffolds designed by Sandia researchers are a step in that direction. Scientists electrospun liquid polymers to create polymer chains, forming a fiber structure. Multi-walled carbon nanotubes incorporated into the fibers provides electrical conductivity. Using this method, the team created scaffolds with two types of polymer, according to Sandia — PBF, which was developed for tissue engineering, and PDMS, a sort of biocompatible caulk. PBF is biodegradable, so the scaffold would disintegrate once installed, leaving the electrical contacts behind. PDMS is not biodegradable.
The idea is that a scaffold would provide a connection between existing nerves and new electronics, containing enough pores to let new nerves grow. The newly innervated limb would then theoretically have the same sensory characteristics as a real one.
This type of transplant is still years away, but recent tests with lab rats show its promise, theSandia news release says. Robotics engineer Steve Buerger, one of the research leads, said the team is pursuing external funding to continue the research, “so we can bring this technology closer to something that will help our wounded warriors, amputees and victims of peripheral nerve injury.”
The work was presented at a winter meeting of the Materials Research Society.


Thursday, 2 February 2012

Is this boy born with night vision the next step in human evolution?


A blue-eyed Chinese boy born with cat-like night vision may offer clues to the future of human evolution.


When Nong Yongsui was two-months-old his father, Nong Shihua, was told by doctors not to worry about his son’s unique blue eyes and that his eyes would be fine when he grew up; now, years later, Yongsui’s father, teacher and doctors are convinced the young boy’s eyes have given him a special ability — night vision.
“In the dark Nong’s eyes would emit a kind of blue-green light when shone upon by a flash light — his eyes were just like cat eyes.”
A Chinese news reel, now available on YouTube, claims that Yongsui’s rare blue eyes glow green when light hits them and allow him to see in the dark as clearly as most people do during the day, an attribute prompting some to call him the next step in human evolution.
The video originally surfaced in 2009 but has just recently gained international attention. The video reports that Yongsui began experiencing blurred vision in daylight, having to squint when playing outside during the day but able to catch crickets at night without needing a flashlight. Bi Donglei, from the Heng County Television Station in Guangxi also claims that Yongsui was able to answer questions she handed him in the dark.
The lack of any definitive evidence has left many skeptical of Yongsui’s abilities. Night vision is made possible in nocturnal animals, such as cats, by a thin layer of cells called the tapetum lucidum. These cells create a “retroreflector” — when a beam of light hits the tapetum, it is reflected directly back along its path. This process amplifies incoming light allowing the animal to see at night, it is also the reason that cat’s eyes flash when they are illuminated.
While many are calling Yongsui’s eyes “cat-like” experts aren’t so sure. “Evolutionarily, mutations can result in differences that allow for new environmental niche exploitation. But such mutations are modified over long periods. A functional tapetum in a human would be just as absurd as a human born with wings. It can’t happen,” said James Reynolds, a pediatric ophthalmologist at State University of New York.
The Alien Disclosure Group, an extraterrestrial and paranormal organization, has offered some different theories, “Could Nong Yongsui be a Hybrid or Starchild? A new and growing generation of extraordinary and gifted children are springing up across our planet, is the human species evolving, or possibly our Extraterrestrial visitors tinkering with our DNA?”
There’s no doubt that Yongsui’s eyes are rare for his ethnicity but without further investigation into his uncommon abilities it’s impossible to know for sure what he sees and why — does he indeed have cat eyes due to a bizarre genetic mutation? Is perhaps another attribute, such as rod-rich retinas, the reason for his improved night vision? We’ll just have to wait and see.
Any readers care to weigh in on these theories or perhaps offer their own?