Save lives for under a buck

A previous student of mine showed me this video, which actually ties in with something I had just found out about a few weeks previously. By combining a cheap, paper microscope that cost about $0.50 to make, and a child’s spinning toy, it is possible to diagnose malaria, which kills millions each year. The microscope is called the Foldscope. It’s printed on a heavy piece of die-cut paper, and then gets cut out and folded into a surprisingly powerful microscope, able to see blood cells. You can preorder these yourself (I have!). The other piece, the spinning toy, replaces expensive centrifuges to separate the blood into components. Coupled together (along with a doctor) you can do the lab work for diagnosing malaria for under $1.

Antibacterial dragonflys

There are a number of things that are naturally antibacterial. Silver, for one. For a long time, people have been using silver in things to help stop diseases. There’s also dragonfly wings. Now, scientists are making surfaces similar to the dragonfly wings to destroy bacteria. These are called nano-textured surfaces (NTS) and might lead to new materials that help prevent diseases.

One way that Math and Science are linked

Everytime math comes into my science class, the students always groan. “Why do we have to do math? We already had math class?” But math and science are linked. In fact, the math has to be there. And it can be really interesting how this happens. A number of years ago, one of my favorite youtubers did a trilogy of videos on this.

The first is on Fibonacci numbers, which seem to pop up all over the place. This then leads to one of my favorite irrational numbers: Phi (Φ). Everyone knows about Pi, but phi is pretty awesome too. Well, actually the golden ratio, which is also used all over the place, and mathematicians use phi as shorthand, kind of like they use pi for the ratio of the circumference of a circle to the diameter.

It turns out that when plants want to grow leaves, but not have the upper leaves be right above the lower leaves, they frequently put the leaves phi degrees away from the previous leaf. How do they do that? It’s not like they have protractors know about geometry or anything. It turns out that it’s really simple, as vihart gets to. It’s just growing where there’s more protein that tells the plant where to grow new leaves. This automatically ends up with the leaves being phi degrees apart. It’s really cool!

Anyway, here are the videos:

First agriculture

Ah, agriculture. That wonderful way of raising crops. Started about 10,000 years ago.

Or did it?

It turns out that humans aren’t the only one’s who raise crops for food. Ants have been doing it for much longer. On particular ant, Philidris nagasau, doesn’t just eat a particular fungus, but when an ant colony splits, they carry a start of the fungus to the new location. They’ve been doing it for over 8 million years, much longer than Homo sapiens has been around.

Food myths

Lifehacker just did an article on Food Myths. That is, things that people think are true, but aren’t. The full article explains each. Here are the myths:

  1. Myth: Eat a hearty breakfast, first thing in the morning.
  2. Myth: You need small meals every 2-3 hours.
  3. Myth: You need to eat immediately after a workout.
  4. Myth: You need to stop eating a few hours before bedtime.

Visualizing Time

Humans have trouble understanding very large and very small quantities. Stuff over a million, or smaller than 1/1000th is just difficult for us to conceptualize. For example, we tend to think that a billion isn’t that much bigger than a million. But there are 1000 millions in a billion.

Likewise, our understanding of time and how long ago things happened is kind of fuzzy. Here is a great visualization of time. (there are some naughty words in there, beware if you are of timid sensibilities)

One thing that I found surprising is that Cleopatra is closer in time to us now, than she is to when the Egyptian pyramids were built.