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Building the Bionic Man Link Bionic Eye: The Argus II bionic eye is currently undergoing trials in 50-75 patients in the US. The system uses a spectacle mounted camera that feeds visual information to 60 electrodes implanted in the retina. Bionic Ear: Cochlear Implant Cochlear implants are one of the oldest pieces of the bionic man, first developed in 1969 by William House and Jack Urban. Although traditionally the devices have been implanted in just one ear, bilateral cochlear implants are currently being trialled as two implants help in localizing sounds. Bionic Brain An artificial hippocampus (part of the brain responsible for storing new memories) is being developed by scientists at the University of Southern California in Los Angeles. Arrays of electrodes record electrical activity coming from the brain and further arrays send appropriate electical instruction back out. The idea is that the implant will be able to bypass damaged areas of brain tissue by replicating it’s function electronically. Bionic Tongue Scientists at the Luebeck Medical University in Germany have conducted successful tests on pigs of the first bionic tongue. The tongue is constructed from throat muscles linked to a device that transmits nerve signals in a similar way to a heart pacemaker. Bionic Nose We are still waiting for a bionic nose but in the meantime development continues on artifical electronic noses. Uses for such technology include laboratory noses for measuring aromas used in R&D for food, beverage, medical and enviromental applications. They are also being used in hospitals for smelling for ’superbugs’. Bionic Heart In July 2001, Robert Tools received the first completely self-contained artifical heart transplant. The Abiocor replacement heart is designed for patients with end-stage heart failure when all other treatment options have been exhausted. Bionic Lung Surgeon Robert Bartlett successfully replaced 100% of the lung function of sheep with an implantable artificial lung. The design used tiny hollow fibers and the hearts own pumping power. Other designs for artificial lungs have used external mechanical pumps to push the blood through the oxygenating device. Bionic Arm Bionic arms work by detecting movements of chest muscle that have been connected to the remains of nerves that once went to the lost limb. The impulses emitted from the transplanted nerves into the chest muscle are picked up by the harness and processed by a computer which then directs very precise movements of the artificial limb. Bionic Kidney Currently, patients with renal failure rely on external dialysis to replace the functions carried out by the human kidney. Work is ongoing on dialysis technology to decrease the size and complexity which will result in implantable bionic kidneys according to Dr. William Fissell, an internist at the University of Michigan School of Medicine: The first step toward that goal, Fissell said, is improving the effectiveness of external artificial kidneys, or hemodialysis devices. Next would be to make an external device small enough for a patient to wear continuously. The final step would be a device that could be implanted, not unlike a pacemaker for the heart. Bionic Liver Dr. Jörg C. Gerlach from the University of Pittsburgh invented a bionic liver that consisted of a tiny pump, a chamber containing human liver cells, and a catheter connecting it all to the patient. This, and other similar projects such as ELAD (extracorporeal liver assist device), produced by Vitagen Incorporated of La Jolla, California, are intended to be a temporary solutions in the event of liver failure rather than a permanent, internal replacement to the human liver. While work continues on integrating mechanical solutions to liver failure, scientists from Newcastle University in the UK have successfully grown a replacement mini-liver from umbilical cord stem cells. The cells were then placed in a “bioreactor” developed by NASA that mimics the effects of weightlessness and allows them to multiply rapidly. Using hormones and chemicals, the stem cells are then coaxed into turning into liver tissue. Bionic Stomach Martin Wickham from the Institute of Food Research has developed an artificial stomach to help decipher how the human gut reacts to various foods and conditions. This device is not intended to be a bionic stomach replacement though as the artificial stomach is not connected to humans and is not designed to replace stomach activitiy. Bionic Legs There are two interesting developments in bionic legs: 1. Replacement bionic legs for amputees. These bionic legs are attached following an amputation to help the patient regain lost limb function. An example of this type of bionic leg is the Victhom Power Knee 2. Augmented bionic legs for soldiers and other heavy lifting applications. Pictured above is the Berkeley Lower Extremity Exoskeleton, or Bleex, is part of a US defence project designed to be used mainly by infantry soldiers. Bionic Anus Aimed at combating severe feacal incontinence, the Acticon Neosphincter simulates normal sphincter function to give the patient control over defecation through a pressurized system. [ permanent link to this entry ]
SPACE SIMULATIONS GALORE Link In the wake of last week's story about NASA's involvement in virtual worlds, I received several messages offering a second opinion about Second Life, and a sampling is provided below. Some correspondents rightly pointed out that online space simulations go back to an era when games were played with stolen mainframe moments. Virtual space adventures have come a long way since Lunar Lander. You can't go wrong with Orbiter, a free sim program that's based on the real physics of spaceflight. Among the more recent entrants in the field is Space Station Sim, which helps you build and populate a virtual space station. One reviewer called it "a rocket-boosted title that won't break the exploration budget," while another said that trying to build an orbital outpost that passed muster resulted in "more frustration than fun." I have the program at home but haven't yet tried it out myself - so I guess it's time to start launching and find out if I have the Right Stuff. Another recently released program, Lunar Explorer, uses actual NASA data to create a virtual moon. And if it's interplanetary travel you're interested in, the NASA World Wind project virtually offers you the solar system (as well as Earth). For an encyclopedic rundown of space simulators, check out the compendium at Clark Lindsey's HobbySpace Log. Here's a sampling of the messages I've received about Second Life: Don Mitchell: "Virtual reality is a success today, but I don't think Second Life has been an especially dramatic or innovative step. Articles in The Register suggest that Second Life is greatly exaggerated (see: 'The phony economics of Second Life'). Personally I found it to be unattractive, and like most subscribers, I left after a couple hours and never returned. "There have been many high-profile but unsuccessful approaches to Virtual Reality: the VRML standard, head mounted displays, SIMNET, and a variety of failed 3-D social worlds before Second Life. The true pioneers of Virtual Reality have been the inventors of computer games. "Text-based multiplayer games (MUDs) showed that large communities could be built online, and that immersion in virtual reality is mostly a function of the user's mind. Brilliant software developers like John Carmack ('Quake') and Tim Sweeney ('Unreal') developed efficient techniques for displaying complex 3-D worlds on the PC. And products like Everquest and World of Warcraft were among the first really successful and compelling examples of multiuser 3-D virtual reality. "Computer games have driven the high-speed computing and graphics technology of the PC and game consoles. Along with motion-picture special effects, games are the most economically important application of 3D graphics thus far." One correspondent dwelled on Second Life's dark side, which I admit I steered clear of during my SL sojourn as Boole Allen: Tyrel (referring to Second Life and NASA): "Seeing those two phrases together bring tears to my eyes. Second Life is an abomination, explicitly showing all that is wrong with the Internet bundled into a package of pornography and sick fetishes. How the multitudes of reporters somehow don't see the sick sides of Second Life and see it worthy of any sort of reporting is beyond me. (If you want to be 'enlightened' to the true sickness of Second Life, visit somethingawful.com's Second Life Safari). "What also makes me furious is that programs professionally written in lieu of space simulations barely get the gratification they deserve (such as this masterpiece of space flight simulation) ... while these poorly written, memory leak-ridden, crap programs with hardly enough physics actually programmed into the engine to make a ball bounce partially realistically get front-page articles on major Web sites. This shows that true journalistic research seems to be a thing of the past, or the highest bidder gets the front-page advertisement." Another correspondent, however, saw a lot of things to praise in Second Life, and his reference to human modification reminded me of our series on the future of evolution: Maelstrom Baphomet: "...You are so fascinated with what we do with our environments in the virtual world that you haven't seen the most significant frontier; what we do with our bodies. If the avatars on this game are any hint at what is coming when men master genetics, I don't think the world will belong to what we constitute as humanity in about 1000 years. Instead, you will have a highly modified and modular intelligent life form. ... "I'll show you places (PG) where dragons roam free and life cycles of their generations are determined by the sun. And we're not talking about human sized dragons.. we're talking about avatars 2-5 times the size of the default avatar in SL. They're built around primative objects that would normally be clothing for the body. Example, a hat is a head. "Daryth Kennedy is the most dominant artist on the sims in question. She's a longtime friend. I came to her the first night I joined SL in 2005 and I wanted to bring one of my characters to life. I provided her a picture, she provided me a dragon. I gave her the rights to reproduce and sell the default dragon we created which became the Storm Dragon as long as she provided me free copies of any future iterations of it. The dragon in question is the storm dragon. It now exists in three formats. Hatchling, Wyrmling, and Adult officially. Players, such as myself, have modified them to humanoid variants. I actually find it quite relieving to be something other than human when the opportunity presents itself - as that's what I do every day, be human. There's also a lot of gizmos and trinkets that can be collected and assembled through out SL that can lend an air of magic to the dragons, making them all the more fantasy come to life. "What people fail to understand is that SL is not virtual reality. It is reality existing in a different state. It's still there, it's just comprised of electrons on a spinning disk, versus atoms on a spinning globe such as humanity is. The characters have souls, it's the souls of the players, giving the creatures on that world life and taking upon themselves a form reflective of their creativity. I am a Christian, and interestingly enough I find this a demonstration of a verse from Genesis where God creates man in his own image. But what is the image of God? God is all powerful, he can make himself whatever he pleases to be ... and true to the script, in this Second Life ... man makes himself in his own image, the manipulable one given by God." For more about Second Life's religious angle, you'll want to check out today's story in USA Today about the virtual holy season. And if you want to weigh in with your own comments - about space simulations, or about good and evil in virtual worlds - feel free. [ permanent link to this entry ]
Superconductors inspire quantum test for dark energy Link Exclusive from New Scientist Print Edition. Subscribe and get 4 free issues. Zeeya Merali, London Dark energy is so befuddling that it's causing some physicists to do their science backwards. "Usually you propose your theory and then work out an experiment to test it," says Christian Beck of Queen Mary, University of London. A few years ago, however, he and his colleague Michael Mackey of McGill University in Montreal, Canada, proposed a table-top experiment to detect the elusive form of energy, without quite knowing why it might work. Now the pair have come up with the theory behind the experiment. "It is certainly an upside-down way of doing things," Beck admits. Dark energy is the mysterious force that many physicists think is causing the expansion of the universe to accelerate. In 2004, Beck and Mackey claimed that the quantum fluctuations of empty space could be the source of dark energy and suggested a test for this idea. This involved measuring the varying current induced by quantum fluctuations in a device called a Josephson junction – a very thin insulator sandwiched between two superconducting layers. Beck reasoned that if quantum fluctuations and dark energy are related, the current in the Josephson junction would die off beyond a certain frequency (see A table-top test for dark energy?). But they hadn't worked out what exactly caused the cut-off. Now the duo say they know, and last week Beck presented the theory at a conference on unsolved problems for the standard model of cosmology held at Imperial College London. Frequency cut-off Quantum mechanics says that the vacuum of space is seething with virtual photons that are popping in and out of existence. Beck and Mackey suggest that when these virtual photons have a frequency below a certain threshold, they are able to interact gravitationally, contributing to dark energy. Their theory is inspired by superconducting materials. "Below a critical temperature, electrons in the material act in a fundamentally different way, and it starts superconducting," says Beck. "So why shouldn't virtual photons also change character below a certain frequency?" If so, virtual photons should behave differently below a frequency of around 2 terahertz, causing any currents in the Josephson junction to taper off above this frequency. Physicist Paul Warburton at University College London is building such a dark energy detector and could have results next year. Some evidence that dark energy works like this may already have been found. In 2006, Martin Tajmar at the Austrian Research Centers facility in Seibersdorf and his colleagues noticed bizarre behaviour in a spinning niobium ring. At room temperature, niobium does not superconduct, and accelerometers around the ring measured that it was spinning at a constant rate. But once the temperature fell, the niobium started to superconduct, and the accelerometers suddenly picked up a signal (Gravity's secret). Odd acceleration "We measured an acceleration even though the ring's motion hadn't changed at all," says Clovis de Matos, who works at the European Space Agency in Paris and established the theory behind the experiment. He thinks the results could be explained if gravity got a boost inside the superconductor. "Beck and Mackey's gravitationally activated photon would have that effect," he says. The controversial experiment seemed to fall foul of Einstein's equivalence principle, which states that all objects should accelerate under gravity at the same rate. It implied that "if you have two elevators, one made of normal matter and one made of superconducting matter, and accelerate them by the same amount, objects inside will feel different accelerations", de Matos says. Astronomers may have seen a similar violation of the principle (see "Two-speed gravity", below). The odd acceleration detected in the niobium ring also suggests that energy isn't conserved in the superconductor – another major violation of known physics. Dark energy could solve that problem, however. "We did the sums and found out that energy wasn't conserved, but perhaps that was just because we were missing dark energy," de Matos says. Paul Frampton, a cosmologist at the University of North Carolina at Chapel Hill, thinks Beck and Mackey's reasoning is flawed. "I don't think for a second they'll measure dark energy, but they should certainly try." [ permanent link to this entry ]
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