24 November 2010

Why you get tired after Thanksgiving dinner. Hint: it’s not Tryptophan.

Really the only thing that doesn't make you sleepy
You know the story. Have thanksgiving dinner in the middle of the afternoon, eat right up until you start to feel sick (and maybe a little more), and then find a couch or chair and fall half-asleep. If it happens, it's likely that someone will blame it on the Turkey. The old myth is that Turkey contains the amino acid tryptophan, which causes drowsiness. None of that is actually false. Turkey does contain tryptophan. And tryptophan is related to sleep – it is the only amino acid that can be converted to serotonin, which regulates our sleep patterns. But take a look at this list. Pork, chicken, and peanuts all have as much or more tryptophan as turkey. And beef and eggs are comparable too. But you don't hear people complaining that they are falling asleep because of the chicken sandwich they had for lunch. So what does make you sleepy at 6pm on Thanksgiving? The answer is: carbs. Think about the rest of the stuff on your plate: mashed potatoes, stuffing, cranberry sauce, breads, sweet potatoes, pie… maybe some vegetables (but who really eats those?). Most of what you eat at thanksgiving is carbohydrates. And the research shows that high carbohydrate meals cause sleepiness by releasing insulin, which releases much more serotonin than you get from the tryptophan in turkey. So now, thanks to my help, when someone at your thanksgiving dinner tomorrow claims they are falling asleep due to the turkey, you can be the annoying nerdy guy who tells them they are wrong. Or just have another piece of pie.

01 November 2010

How 3-D TV Works

You have probably looked at 3-D images before with those goofy red and blue glasses. You may have even watched something in 3-D before. Maybe in a movie theater, maybe a TV broadcast from past years. I have done all of these things, but I still thought of 3-D movies or TV shows as a clunky gimmick. So it's a surprise to me as I keep seeing news stories about 3-D TV's. I wanted to know why, all of a sudden, everything needs to be watched in 3-D. As I figured, it comes down to technology.

How This Stuff Works

3DTV's - Not really like this. (MarkWallace)
Most 3-D technologies work by giving the viewer a different image for each eye. Differences in the images give an illusion of depth and make objects appear to be popping out from the screen. 3-D content is easy to produce, just by recording the same thing with two camera lenses in slightly different positions. It is easy enough to be used for many sporting events now. The trick is getting separate images from the screen to each eye of the viewer.

The old red and blue glasses did this by tinting the two images, so the eye with the blue lens could not see the blue parts of the image, and vise-verse. But this messes with the colors and everything ends up seeming blurry, so it didn't catch on. Polarization is another method, used today in movie theaters. Read more here about light polarization. Put simply, two different projectors show images with different types of light, and filters on your glasses block one type of light for each eye. This method requires special coatings on the screen and technology to project two images at the same time, but general consensus is that polarization is the current technology with the best viewing experience.

A Collection of Technologies

The method used in the new home 3-D TV sets is neither of these, and unlike the previous methods, does not