Note (12/2015): Hi there! I'm taking some time off here to focus on other projects for a bit. As of October 2016, those other projects include a science book series for kids titled Things That Make You Go Yuck! -- available at Barnes and Noble, Amazon and (hopefully) a bookstore near you!

Co-author Jenn Dlugos and I are also doing some extremely ridiculous things over at Drinkstorm Studios, including our award-winning webseries, Magicland.

There are also a full 100 posts right here in the archives, and feel free to drop me a line at secondhandscience@gmail.com with comments, suggestions or wacky cold fusion ideas. Cheers!

· Categories: Biology
What I’ve Learned:

Prions: Teaching new proteins fold tricks.
“Prions: Teaching new proteins fold tricks.”

Any neat freak with a hint of OCD can tell you that folding is important. If you two-fold your towels, then a tri-folded one clearly won’t do. If you’re a T-shirt sleeve tucker-underer, then a sideways-folded-over one is just going to make you twitch. And don’t even get me started on socks. I’m pretty sure the Crimean War was started over the improper folding of a pair of tube socks. You can look it up.

What most people don’t realize, though, is that folding is pretty important in other areas, too. Take protein folding, for instance. It’s easy to take protein folding for granted. You probably figure if one of your cells managed to make a protein properly — without any mutations in the gene, or DNA transcription errors, or messenger RNA misreads, or a thousand other pitfalls that can hork a protein entirely — then the hard part is over. But no. That protein still has to fold itself properly, like some tiny automated scrap of origami, to be of any use.

And what happens when the protein doesn’t fold the right way, and helix B wraps around sheet C, instead of sheet A like it’s supposed to? If it’s a specific type of protein found in humans, other mammals, some fungi and possibly elsewhere, then it becomes something called a prion. And that’s very bad.

(Worse than a pair of khakis folded away from the crease? Ay, chihuahua!)

The “common” (or “cellular”) version of the potential-prion protein is found throughout the bodies of humans and animals, in many different kinds of cells. This version is folded correctly, is anchored to the outer membranes of cells, and is thought to be involved in interactions between cells, including intercellular communication like signals passing through neurons in the brain. And as long as it’s pretzeled up the way it should be, there aren’t any problems.

But under certain conditions, this protein doesn’t fold quite right, and that leads to a snowballing set of problems. First, the misfolded prion can interact with “good” versions of the protein, and rejigger them in its image — namely, as bent-out-of-shape kinked-up beasts, ready to wreak havoc all around. Think of the self-replicating Smiths from those Matrix movies that weren’t as good as the first one, only with a hunchback or double-jointed knees or something.

The bigger problem is that these refolded prions can then link together in chains called fibrils, gradually forming huge structures called amyloid aggregates. These aggregates grow larger and larger, until they eventually disrupt cells and tissues — often in the brain. I’m no fancy neuroscientator person, but even I know that having an ever-growing Lego set inside your skull is probably not a good thing.

In fact, it’s an incredibly bad thing. Active prions lead to diseases known as spongiform encephalopathies, where “encephalopathies” means “brain diseases” and “spongiform” means “looking like a sponge”. Brain sponge disease. So the term isn’t as complicated as it sounds — but it’s several million times more frightening.

In sheep, prions cause a nasty-sounding disease called scrapie, and in cows, bovine spongiform encephalopathy, better known as mad cow disease. Humans get the misleadingly innocuously-named kuru, and then some diseases named more appropriately for a horror that turns your brain to Swiss cheese: Creutzfeldt-Jakob disease and Gerstmass-Straussler-Scheinker syndrome, for two.

Sadly, prion diseases are currently untreatable, and universally fatal. On the bright side, if you can manage not to eat the diseased brain of a sheep, cow or sworn enemy that has the disease, you’re pretty unlikely to get it yourself. But just to be safe, whether it’s laundry or proteins — pay attention to your folding. You can’t be too careful.

Image sources: Currents in Biology (prion), MacGyverisms (wrong socks, WRONG!), Twilight Language (“Hello, Mr. Smiths!”), Sargento (Swiss cheese)

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· Categories: Computers
What I’ve Learned:

Swarm robotics: You guys like swarms of things, right?
“Swarm robotics: You guys like swarms of things, right?”

Lots of great things come in swarms. Hornets. Locusts. One Direction fans.

Okay, so none of those things are particularly great. But robots are pretty great, and now robots come in swarms, too.

Swarm robotics hasn’t been around long, since it requires robots with three characteristics of animals that swarm together: small size, good mobility and cheap production.

And in the case of 1D fans, squealiness. But that’s not as important.

The concept behind swarm robotics is borrowed from biology, and is called “emergent behavior”. Basically, it’s the idea that a bunch of mostly-identical critters of limited intelligence can work together to do something useful that they couldn’t manage as individuals. In nature, that might be to migrate to a new nest or strip a cornfield down to its roots. Or to vote Harry Styles dreamiest Teen Beat dreamboat.

Happily, when it comes to swarm robotics, the mechanical critters — or the people programming them — are usually more sensible.

The ultimate goals of swarm robotics include things like digging mines or harvesting crops or building structures. Someday, particularly tiny robots might scurry into our bodies to clear out arteries or slice up a tumor or slap together a new liver.

Or they’ll take over the planet, build a machine city and plug all of surviving humanity into the Matrix. Which would be slightly less helpful.

For the moment, scientists are limited to current robot technology, which includes wheeled self-assembling Rubik-sized cubes and coin-sized microbots that skitter around on toothpick legs. Neither is very impressive in the singular — they’re like miniaturized Roombas that don’t bother to vacuum any more. But with a bunch of these robots (and the right programming), engineers can do some pretty interesting things.

With a few simple instructions, for instance, swarm robots have assembled to pass obstacles a single unit couldn’t navigate, and to collectively move objects much heavier than any component robot. There are even termite-inspired projects with robots that cooperatively figure out how to build simple structure designs. And recently, a team at Harvard University coaxed the largest-yet swarm of teenybots — over one thousand strong — to arrange themselves into specified shapes, using a set of extremely basic rules.

So long as one of those shapes wasn’t “Skynet”, we’re probably going to be okay. For a few more years, at least.

The real power of swarm robotics comes with numbers. As the motors and sensors and other fiddly bits get smaller and cheaper, scientists can put more of their robo-critters into action. For some jobs, it doesn’t matter if one, or even half, of them fails. Sheer numbers — and a few snippets of code — will see them through larger and larger tasks. It’s like having a nest full of insects ready to do your bidding, or a tiny team of not-especially-bright butlers waiting to serve your every whim.

So while our future could hold Matrix enslavement — or worse, an endless horde of angry Benders — for now, swarm robotics is a promising field that may help us solve some very tricky and important engineering problems.

Like getting rid of One Direction. Seriously, robotics people. How come none of you is working on that?

Image sources: RedOrbit (sea of Kilobots), Zimbio (squealy concert girls), Gunaxin (Matrix robot swarm face), Den of Geek (Bender horde)

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· Categories: Astronomy, Physics
What I’ve Learned:

Hypervelocity stars: what happens in the galaxy doesn't always stay there.
“Hypervelocity stars: what happens in the galaxy doesn’t always stay there.”

Many things move at a proverbial “million miles an hour”. Vacation days. Your heart, when a hot-bodied stranger in a swimsuit walks by. And your gossipy friends’ mouths, telling everyone how you drool over hot-bodied swimsuited strangers on your vacation.

You knew you should have never invited them to Cancun. Live and learn, gringo caliente. Live and learn.

Some things that don’t literally move that fast are stars. Sure, stars are usually clustered into galaxies, and galaxies zoom around the void at a million miles an hour or more — depending on which other bits of celestial fluff you measure them against. But the stars are just along for the ride; relative to their host galaxies, they don’t reach those insane kinds of speeds.

Except when they do.

The universe is full of exceptions — even Keanu Reeves made that one good movie once — and turbocharged stars are interesting examples. Known as hypervelocity stars, they whip around at speeds up to two million miles per hour, relative to galactic speed.

That’s like gunning a Ferrari down the highway and being overtaken by a cruise missile. Even your motormouth vacation friends can’t keep up that pace.

Hypervelocity stars are fairly new to astrophysics — predicted in 1988, and first observed in 2005. There are only a handful known to exist, mostly because confirming their speed requires measurements over a period of decades. We can’t exactly set up a speed trap and flash these things with a radar gun as they zoom past.

The really interesting thing about hypervelocity stars is that they move so fast, they can reach the escape velocity of their galaxies. Meaning, instead of swirling around in a galactic spiral forever like our boring old sun, these stars break completely free of galactic gravity and ping off into interstellar space, never to be heard from again.

(Maybe somebody could have pitched that to Keanu Reeves after the first Matrix. I’m just saying.)

What we don’t know for sure is how these stars get all hypervelocitized in the first place. But two theories explain the current observations pretty well.

It’s thought that some hypervelocity stars are formed near our galactic center, where a supermassive black hole looms. Computer models say if a binary system — two stars closely orbiting each other — got caught in the black hole’s clutches, one could be sucked in while the other is flung outward at ridiculous speed. Like a marble fired from a slingshot shot out of a cannon mounted on a jet plane. Times a lot.

The other, equally violent, theory also involves binary systems. Only in this scenario, the partner star isn’t stuffed into a black hole; instead, it goes supernova — exploding so catastrophically that it accelerates the surviving star to supergalactic speeds.

Either way, the presence of a hypervelocity star means that things went terribly, terribly wrong for that star’s old flame. So basically, if your sweetie ever tells you he or she wants to become a hypervelocity star some day, you should pack your bags and leave. Like, yesterday.

You can always take a rebound trip to Cancun. Your friends may gossip, but at least none of those swimsuited hotties are going to explode you or unceremoniously stuff you down a black hole. That kind of shit only happens in Las Vegas.

And apparently, all around the Milky Way. Stellar breakups are a bitch, yo.

Image sources: Tech Guru Daily (hypervelocity star), El Horizonte (beach bods), Oh No They Didn’t! (fast Keanu), Universe Today (binary breakup)

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