Comment Re:Every time a bell rings (Score 3, Interesting) 309
You mean like in the Babylon 5 season 3 finale, where Sheridan jumps to his death on Z'ha'dum and is brought back to life to lead the alliance against the Shadows and Vorlons?
Oh wait, that's the opposite of what you were trying to say.
And Babylon 5 was the best SF to ever hit TV...
Comment Re:Tetrachromat question (Score 1) 311
There are basically 5 types of cells in the retina: photoreceptors (rods & cones), bipolar cells, amacrine cells, horizontal cells, and ganglion cells.
Photoreceptors transmute light into electro-chemical signals with photopigments, bipolar cells link multiple photoreceptors in a lateral inhibition configuration and perform basic luminosity gradient/edge detection preprocessing. The amacrine and horizontal cells are involved in motion detection and image smoothing, but I don't know much about them. The bipolar cells doing edge detection feed into ganglion cells which connect to the optic nerve to send that signal to the visual cortex, which does more complex feature discrimination (bars, lines etc...).
There are separate ganglion cells which perform rate coded colour detection through what's called the opponent process. There are only two types: blue/yellow and red/green.
The red/green ganglia are easy to describe, they are excited by the red cone photoreceptors and inhibited by the green cone photoreceptors. These signals combine to determine the rate of firing of the ganglion cell. So lots of red light means the red/green ganglia fire rapidly, signalling we are seeing red. Lots of green light makes the red/green ganglia fire slowly or not at all, signalling we are seeing green.
The blue/yellow ganglia are a little more complex, they are excited by the red *and* green cone photoreceptors, and inhibited by the blue cone photoreceptors (synaptic weights from the cones to the ganglia are not equal). So lots of reg+green light = blue/yellow ganglia increase rate of firing signalling yellow, while lots of blue light = blue/yellow ganglia decrease rate of firing signalling blue.
Incidentally, this is why red & green and blue & yellow are "complementary" colours, and accounts for many afterimage effects (e.g. stare are something, then stare at a blank wall) - the retina can't physically signal red and green or blue and yellow at the same time.
The signal being sent along the optic nerve from the ganglia then consists of basically three channels: a luminosity gradient, red/green and blue/yellow. The specific ganglion sending the signal indicates where it was detected in retinotopic space. I am specifically leaving out the amacrine/horizontal cells here, I know they are involved somehow in signal modulation and motion detection, but again, I don't really know how that system works.
The preprocessing done by the retina on visual input can be broken down into three broad categories: edge detection, colour detection and motion detection. The retinal signal is then processed using what I like to call "magic" in the visual cortex to create our perceptions.
Hope this helps!
Comment Obligatory - Why 3D doesn't work and never will... (Score 5, Informative) 404
Comment Re:Google! (Score 1) 214
They have Bing already
They have a what now?!?
Comment Step 1) (Score 1) 155
Don't get on a plane!
Comment Re:So why aren't we doing it? (Score 1) 990
it's *arbitrarily* more convenient for most people
You keep using that word. I do not think it means what you think it means.
Submission + - Possible cure for the common cold and more (marginalrevolution.com)
HardYakka writes: A team of researchers at MIT's Lincoln Laboratory have designed a drug that can identify cells that have been infected by any type of virus, then kill those cells to terminate the infection.
The researchers tested their drug against 15 viruses, and found it was effective against all of them — including rhinoviruses that cause the common cold, H1N1 influenza, a stomach virus, a polio virus, dengue fever and several other types of hemorrhagic fever.
The researchers tested their drug against 15 viruses, and found it was effective against all of them — including rhinoviruses that cause the common cold, H1N1 influenza, a stomach virus, a polio virus, dengue fever and several other types of hemorrhagic fever.
Submission + - Terrorist target mexican nanotechnology professors (m-x.com.mx)
An anonymous reader writes: A new mexican terrorist organization sent an explosive device to an ITESM professor due to his research in nanotechnology. ITS or Individuals with Wild Tendencies in english, is a group that claims to be against the "nanotechnology revolution" in fear of a nanomachine take over that will mean the end of civilization. The group has published in their website that they plan to target individuals in this research field to ensure the survival of mankind. Mexican authorities are investigating the case.
Submission + - Video: Why Advertised Broadband Speeds Are Bunk (itworld.com)
jfruhlinger writes: "From the beginning of home Internet connections, as we moved through increasingly faster dialup modems to DSL and cable, there was one constant: when we wanted to know how fast our connections were, we were told how many bits (or bytes, or KB, or MB) per second we could download. But now, as more and more people rely on their broadband connection to stream (not download) video, raw download speeds have become less important than various quality of service metrics. The only catch is that broadband providers, who also want to sell you cable TV, have no incentive to advertise — or improve — the numbers you really care about."
Submission + - Language app helps U.S. troops in Afghanistan (cnn.com)
w0lver writes: "A new iPhone app is helping soldiers deployed overseas overcome a major obstacle: the language barrier. More information about the app can be found here: http://triplingo.com/products/afghanistan"
Submission + - Feds' radios have significant security flaws (wsj.com) 1
OverTheGeicoE writes: The Wall Street Journal has a story describing how the portable radios used by many federal law enforcement agents have major security flaws that allow for easy eavesdropping and jamming. Details are in a new study being released today. The authors of the study were able to intercept hundreds of hours of sensitive traffic inadvertently sent without encryption over the past two years. They also describe how a texting toy targeted at teenage girls can be modified to jam transmissions from the affected radios, either encrypted or not.
Submission + - Google Pulls Plug on Programming for the Masses 1
theodp writes: Google has decided to pull the plug on Android App Inventor, which was once touted as a game-changer for introductory computer science. In an odd post, Google encourages folks to 'Get Started!' with the very product it's announcing will be discontinued as a Google product. The move leaves CS Prof David Wolber baffled. ' In the case of App Inventor,' writes Wolber, 'the decision affects more than just your typical early adopter techie. It hurts kids and schools, and outfits like Iridescent, who use App Inventor in their Technovation after-school programs for high school girls, and Youth Radio's Mobile Action Lab, which teaches app building to kids in Oakland California. You've hurt professors and K-12 educators who have developed new courses and curricula with App Inventor at the core. You've hurt universities who have redesigned their programs.' Wolber adds: 'Even looking at it from Google's perspective, I find the decision puzzling. App Inventor was a public relations dream. Democratizing app building, empowering kids, women, and underrepresented groups — this is good press for a company continually in the news for anti-trust and other far less appealing issues. And the cost-benefit of the cut was negligible-believe it or not, App Inventor was a small team of just 5+ employees! The Math doesn't make sense.'
Submission + - Right-Wing Extremists Tricked by Trojan Shirts (spiegel.de)
gzipped_tar writes: Fans at a recent right-wing extremist rock festival in Germany thought they were getting free T-shirts that reflected their nationalistic worldview. But after the garment's first wash they discovered otherwise. The original image rinsed away to reveal a hidden message from an activist group. It reads: "If your T-shirt can do it, so can you. We'll help to free you from right-wing extremism."
Comment Re:I still use telnet (Score 1) 380
Bah! Telnet!
You kids and your new fangled tech!
Gopher is where it's at!!! If I can't find you on WAIS you might as well not exist!
