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.

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

Issues: Coal Reserves

I am interested in looking at the future of energy. From an engineering perspective, providing electricity and the power for transportation is one of the great accomplishments in history. But it's clear that 100 years from now, it won't be done the way it is today. So I am curious about how it will be done, particularly for transportation. First I wanted to see where we are with the current methods, like fossil fuels. Coal provides about half of the electricity for the US and for the world, so let's see how much coal we have left. Sorry if this is a little long, but there was plenty of interesting information. Also, I am just trying to answer the question of how long would coal last if we kept using it, I am not trying to get into any discussions about political or environmental impact. At least not yet.

There is more energy available in coal reserves than in oil or natural gas. Coal reserves are also more widely distributed between countries of the world than other fossil fuels. Getting a handle on how much coal is left for the world to use is not simple. The most widely agreed upon number is around 900 billion tons, from the U.S. Energy Information Administration, the World Energy Council, and BP's annual report on energy assets. This number is the amount of "Proven" reserves, which is not the total amount of coal in the ground, but the amount that makes economic sense to dig up under current conditions.

Where is the Coal?  (Gunnmap)

In reality there are vast amounts of coal (and oil and natural gas) that we will never use. The EIA estimates that in the United States alone, there are between 2 and 4 trillion tons of coal in the ground, but only about 500 Billion tons are technologically feasible to mine, and only half of that is economically feasible. These reserves change over time – up from new discoveries of reserves, better technology to put more reserves in play, and the addition of more economically feasible reserves as coal prices increase. The 900 billion tons has been steady for a while, but it is more likely an overestimate than an underestimate, because reserve numbers are not updated very well. China, for example, is still using reserve numbers from 1992, despite having mined about 20% of that amount since then. In all of our time so far, humans have burned about one quarter of the coal that would make up our reserves today. Europe is down to less than half of what it started with. But given a need for coal and no cost-effective alternative (a poor assumption), it is reasonable that we could mine twice the amount we current consider reserves.

None of that answered the question of how long the questionable amount of coal reserves will last. If we assume those 900 Billion tons are all we can mine, then it will last about 120 years at current production. But worldwide coal production and usage has been climbing rapidly, at a little over 5% per year for about the last ten. If that continues, then the world will run out in 40 years.

That scenario is unlikely, even without a push towards renewable electricity. The growth will start to plateau at some point. But some growth will happen, and 120 years is very optimistic, even figuring we double the potential reserves with new finds. Any estimates that claim 250 years of coal reserves are either overly-optimistic, or are considering only the United States.

The United States not only has the largest coal reserves in the world (Russia is second), but is mining relatively slowly (though is still the #2 producer). At current rates, the US has a little over 200 years before current reserves are exhausted. Compare that to China, which has the third largest reserves, but is mining almost three times more than the US, meaning that they have only 41 years at current rates. The EU has 51 years. As other countries begin to run out, production in the US might pick up for exports, so it makes sense to analyze this globally.

All of this might be a needless way looking at coal production, because economic factors might be too important for the world to ever end up completely running out of coal. There is the idea of production peaks (see peak oil) for finite resources, where, well before a resource runs out, it climbs to a maximum production, then falls over time until the resource is depleted. Now, the reasons for this are both physical and economic, and honestly beyond me. A peak in coal production may happen well before 2050, followed by anything from a global crisis - if the need for coal stays but supply drops - to no problems - if the world smoothly switches to other forms of energy as production declines. A common estimate for this coal peak is 2025, but predictions vary wildly, and peaks are difficult to predict (I.E. the oil peak may have already happened, but we won't know for sure until we see a few more years of data).

So, regardless of any peak, somewhere between 60 and 80 years of coal is likely available if a major shift is not made in coal usage. But a major shift is what I am concerned about. Oil and natural gas reserves will run out well before coal, so an option to keep in mind, along with other alternatives, is to use coal to replace other fossil fuels, with coal-to-methanol or coal gasification. I might write about them later, but it appears that the numbers don't support these methods. Replacing oil with coal will reduce the reserves of coal faster and still put the year of depletion around the same time for either scenario. It may be worthwhile to discuss these processes from a standpoint of energy independence, so the US could cut down on oil imports, and again, I am ignoring (for now) everything about CO2 emissions. I'll get to some of those topics in another post.

A Photograph of Philosophical Importance

Take a look at this photograph.

At first it might appear slightly interesting, a black and white photo, clearly from many decades ago. But this photograph is special because of its timing. This was taken way back in 1838, by Louis Daguerre as he was experimenting with the process to record images. It is of the Boulevard du Temple in Paris, and is one of the first photographs ever taken. Now the streets of Paris were not as empty as they appear here. Early photographs had to be exposed for several minutes (over ten for this one) to collect enough light, so anything that is not completely still for that time becomes a blur, and anything moving faster than a snail is invisible. Notice how blurry the trees are compared to buildings or streetlamps. This street was probably busy, but the moving people and carriages blended into the background. Except in the lower left. Let me zoom in. 

 

A shoeshine and his customer were still enough to be captured in this photograph. That makes this the earliest photograph of a person. Let me repeat that: Above is the very first photograph of a human being. Just something to think about.


 

Anti-Aging Science

Most things with the words Anti-Aging attached would take quite a leap to be considered science.  But there is some real research in the area.  Here is something that looks like a mini-breakthrough.  A study has found a compound that was given to people as a dietary supplement, and may slow down the process of aging (but not stop or reverse it).  It works by activating enzymes in our body that rebuild parts of DNA (telomeres) which shorten over time and may play a part in making us old and wrinkly.  Telomeres also have something to do with AIDS, so this could be used as a treatment for AIDS patients also.  Read a more in-depth summary of the research here.

A Lake in Antarctica

In a radar image, Lake Vostok appears as a smooth patch. (NASA)

One of the largest lakes in the world is located in Antarctica. If you are familiar with Antarctica, this should sound strange, because the entire continent is covered with ice. It should be too cold for lakes to exist there, and that is true…on the surface. But some unique conditions exist that allow lakes of liquid water to form under kilometers of ice. They are called subglacial lakes, and about 150 have been found in Antarctica. Geothermal heat rises from the bedrock below the glacier, and the glacier itself traps the heat at the base, keeping it insulated from the surface, where the temperature can be -60C (-75F). The heat melts the bottom of the glacier, and depressions in the bedrock trap the liquid water as the glacier slides overtop, sealing it off. At high pressure water freezes at lower temperatures, so the millions of tons of ice pressing on the lake makes its temperature hover around -3C (27F), despite the lake being fresh water.

The largest of the subglacial lakes is called lake Vostok, after the Russian research station that sits on the ice 4000 meters (13,000 ft) above the lake. The lake is approximately the same size and shape as lake Ontario (250km by 50km). With an average depth of over 300m (1000 ft), Vostok is the 7^th largest lake on Earth by volume.

Most interesting about lake Vostok is its potential as an ecosystem. The lake has been sealed off from the surface for at least one million years. It is possible that bacteria or other microorganisms have adapted to the unique environment of the lake, and a unique set of species may live in it. Space scientists are especially interested, because lake Vostok is incredibly similar to liquid oceans that are probably below the icy surfaces of Jupiter's moon Europa and Saturn's Enceladus. Sealed from the surface and with no sunlight, if life continues to exist in lake Vostok after millions of years, it would be the best evidence yet that those moons may be hosting primitive life right now. The lake can also be used to test robots that we might send to investigate the ocean below Europa. We might know more about life in the lake very shortly. The Russian research team has been drilling down to the lake for about 15 years, stopping and starting many times, partially for concerns about contaminating the sterile lake. In March of this year, they announced that they are only 100 meters from the surface of the lake, and expect to break through some time this winter.

Update: Micro-pumps for micro-needle patches!

Patch Pump for Vaccine Delivery (Purdue University)

Remember a few weeks ago, I linked to an article about micro-needle patches? They were an ingenious new way to deliver vaccines easily (and painlessly). However, this new article mentions a problem not stated in the previous one; Large molecules of many drugs do not readily dissolve out of the needles and into the skin. For that, they needed a pump of some sort to drive the medicine into the skin. Scientists at Purdue University have done just that! The mechanism seems complicated (and slightly worrisome if something were to break in the pump), but it's still in the testing phase, so lets just get excited about it!

New pump created for microneedle drug-delivery patch.

Link: New Dinosaur may be Closest Relative to Modern Birds!

As a kid, when most other kids wanted to become pop stars or actresses or astronauts, I wanted to be a paleontologist. A part of me regrets not following that path in life, but I can still get excited when a new dinosaur is discovered!

Left leg and foot of Balaur bondoc.
Credit: Mick Ellison; Zoltan Csiki;
Matyas Vremir; Stephan Brusatte;
Mark Norell; AMNH

Last month, paleontologists in Transylvania described a new dinosaur from fossils dug up in September of last year. They called the dinosaur Balaur bondoc, which basically means "stocky dragon" and is part of the dromaeosaurid theropod group, which also includes velociraptor and deinonychus. They are also the group of dinosaurs that spawned the line of modern birds. This new dinosaur has some morphological differences from other theropods, including two large foot claws, opposed to other raptors' single large claw. Balaur's hand bones are heavily fused, with only two working digits, which is believed to be an evolutionary precursor to modern birds' wings. These, among other features, make paleontologists believe that Balaur is the closest known relative to modern birds.

Very Cool.

A "stocky dragon" from Transylvania.

Beefy dino sported fearsome claws.

Balaur bondoc: A raptor unlike any you have ever seen.