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!

Special Relativity


· Categories: Physics
What I’ve Learned:

Special relativity: out with the aether, in with the aother.
“Special relativity: out with the aether, in with the aother.”

On the heels of the holiday season, you may have recently witnessed instances of “special relativity”. Grandma’s secret-recipe fruitcake pucks. Your uncle’s uncomfortably falsetto rendition of “O Holy Night”. Cousin Lem’s drunken faceplant into a bowl of Christmas bisque.

Happily, that’s not the only sort of special relativity. One hundred and ten years ago, Albert Einstein (with a little help from his friends) developed a theory that explained the behavior of things that travel near the speed of light. Like New York City taxis, or Usain Bolt. Or, you know, light.

This theory was needed because by the late 1800s, scientists had figured out that their plain old regular-speed relativity — based on work by Galileo and Newton, among others — wasn’t always getting the job done. This old school theory, called Newtonian relativity or Galilean invariance, because see the previous sentence, sport, said there is an “absolute space” and an “absolute time”, in which everything happens. And by that time, it also included an “absolute reference frame”, a universally unique point of view from which electromagnetic wave properties like the speed of light could be accurately measured.

Problem was, experiments suggested that if that uniquely-accurate reference frame (known as the “aether”) existed, all measurements made in labs were consistently in agreement with it. In other words, all those labs were stationary with respect to this spatial frame of reference. Which would be super, if we didn’t know that the Earth is constantly swooping around the sun (and the sun around the Milky Way, and the Milky Way hurtling through the universe), so it’s not really “stationary” compared to anything but itself.

Einstein dropped this “aether” concept down the nearest aelevator shaft, and that was just the beginning. He also decided that space and time were two great tastes that taste greater together, and mushed them together into something called “spacetime”. And he said no matter how fast you’re going (or not), the speed of light will always look the same. That let a whole bunch of crazy — but later experimentally verified — cats out of the physics bag. For instance:

Under special relativity, two people moving at different speeds may watch the same event happen, but observe it occurring at different times. And not just because one of them has TiVo, either.

If you watch two clocks — one moving and one sitting still — the moving clock appear to go slower. (And if it’s moving while you’re sitting in your office at ten minutes til five on a Friday afternoon, it’ll appear to go reeeeeeeeally slow.)

Mass and energy are equivalent, as given in Einstein’s famous special relativistic equation, E = mc2. This is obvious to anyone who’s eaten a four-ounce chocolate eclair and felt the kajillion-calorie jolt to their metabolism as the mass is converted to energy… and then seen six pounds of flab appear on their ass as it converts back to mass.

(I don’t know why it gets bigger in the conversion. What am I, some wild-haired German genius math guy?)

Basically, Einstein’s special relativity theory made some predictions crazier than drunk old Cousin Lem on an eggnog bender, but they turned out to be true where Newtonian relativity did not. Either theory will get you through the day for normal stuff — but if you’re zooming around near the speed of light, then you’d damned well better listen to Einstein.

He may not be your relative. But believe me — he’s special.

Actual Science:
LiveScience – What is relativity?
American Museum of Natural History – Special relativity
HowStuffWorks – How special relativity works
io9 – Get pelted every day with particles that confirm special relativity
The Physics Classroom – Relativistic length contraction

Image sources: QuickMeme (it’s all relativity), Telegraph (UK) (blurry Bolt), Food Navigator (food faceplant), London Evening Standard (an eclair and present danger)

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Prions


· 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.

Actual Science:
University of Utah Health Sciences – Prions: on the trail of killer proteins
Scientific American – Prions may develop drug resistance
Science 2.0 – Yeast cells can cure themselves of prions associated with Alzheimer’s
The Scientist – The bright side of prions
Nature – Prions and chaperones: outside the fold
RedOrbit – Scrapie could be transmissible to humans after all

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

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Mpemba Effect


· Categories: Physics
What I’ve Learned:

Mpemba effect: Warm... hot!... HOT! Cold.
“Mpemba effect: Warm… hot!… HOT! Cold.”

Science is sometimes all about observation — particularly when the thing being observed makes no damned sense, and clearly needs some brainy scientist to figure it out and explain it. For instance, take the following observation:

Under certain conditions, warm water will freeze faster than cold water.

I told you it made no damned sense. This is real up-is-doAwn, black-is-white, Tom-and-Jerry-living-together-in-scandalous-nude-beach-sin kind of stuff.

But it’s also true, and the phenomenon has drawn attention for millennia. Some of the greatest minds of the Western world have puzzled over the problem — Aristotle, Sir Francis Bacon and Rene Descartes, for three. They all tried to suss out why hot water can sometimes freeze faster, and all of their explanations had one thing in common:

They were fairly spectacularly wrong.

To be fair, none of these guys was a professional waterologist, or whatever esoteric specialty the question would fall under. Still, that’s a pretty all-star lineup to be stumped by a puddle of warm water. That’s like the Harlem Globetrotters botching a layup. It simply isn’t done — and it’s probably why the phenomenon isn’t named for any of those people.

The person it is named for is Erasto Mpemba, who was neither a famous (yet) scientist nor a globetrotting basketball trickster. Instead, he was a young student in the 1960s in Tanzania when he asked visiting physics lecturer Denis G. Osborne what gives with this quick-freezing hot water business. Between them, they repeated and confirmed the basic observation, published a short paper on the subject in 1969, and the phenomenon has been known as the Mpemba effect ever since.

Which seems a little like cheating, since Mpemba didn’t really explain what was causing it, either. The lesson here seems to be: if you want something named after you in science, you need to wait for a historical period littered with hippies, when maybe the rules for taking credit are relaxed a little bit. If more of Francis Bacon’s peers had smoked weed and played the sitar, maybe the Mpemba effect would be all his, instead. We’ll never know.

(Also, if your last name is “Osborne”, you’re going to have to do some way crazier shit to get people to remember you. That bar’s set pretty high at this point.)

But there’s another lesson (and some actual science) in more recent work on the matter. The lesson is: if some weirdo science thing is already named after someone, doing the work to actually explain it still won’t get your name on it. Happily, that didn’t stop Xi Zhang and colleagues in 2013 from digging in and getting their hands dirty, mechanistically speaking.

They concluded that the Mpemba effect occurs due to hydrogen bonding in water. These hydrogen bonds across water molecules, much weaker than the covalent bonds holding oxygen and hydrogen atoms within the molecules together, can form and stretch and break at will. It’s known that hydrogen bonds in water compress the covalent bonds, and that heating water will push the molecules further apart, stretching the hydrogen bonds — and further squishing the covalent ones.

The idea is that “hotter water”, with its more tightly spring-wound energy tied up in covalent bonds, will release this energy more quickly than cooler water. Losing this energy is a type of cooling, so the heated water really will cool — and freeze — faster. It’s a neat and tidy explanation for a quirky “stupid water trick”.

Is it right? The debate is still out. Some scientists argue that greater evaporation in the heated water is the main force at work, while others attribute Mpemba effects to gases dissolved in the water samples. It’ll take a lot more scientist frostbite — sorry, make that scientists’ graduate student frostbite — before anyone reaches a consensus.

Meanwhile, Erasto Mpemba can rest easy, knowing that he brought to light a puzzle haunting humankind since the time of the ancient Greeks — even if he didn’t bother to explain it. Thanks, hippies!

Actual Science:
Phys.org – Mpemba effect: why hot water can freeze faster than cold
Wired – What’s up with that: the mysterious effect that makes hot water freeze faster than cold
Medium / The Physics Arxiv Blog – Why hot water freezes faster than cold – physicists solve the Mpemba effect
Gizmodo – We’ve finally figured out why hot water freezes faster than cold

Image sources: Cool Science Stuff (Mpemba ice), FanPop (T&J, tanning), Sportales (the ‘Trotter split) and Spultured (Ozzy, presumably preparing to bite the head off something)

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Z-DNA


· Categories: Biology, Genetics
What I’ve Learned:

Z-DNA: Because everybody needs a little time to unwind.
“Z-DNA: Because everybody needs a little time to unwind.”

Maybe you’re familiar with the fundamentals of DNA. A pair of organic biopolymer strands composed of covalently-bonded nucleotide molecules, wrapped together in a double helix. It’s not exactly simple. But the basics are pretty well established, thanks to Watson and Crick (and Franklin, and Gosling, and a bunch of others). If that’s as complicated as it gets, super.

Naturally, it gets more complicated. The universe is a smug little infinitely-large bitch, yo.

One way DNA gets harder is the way that pair of helices wrap around each other. You’d think there’d just be one way to fit, like Legos clicking together. But no. A DNA double helix is more like a jigsaw puzzle: if you get really frustrated and smush the pieces into those little holes, it’ll go together just about any way you want.

In nature — which in this case means, in you — DNA comes in (at least) three forms. The usual, vanilla, run-of-the-mill DNA in most of your cells is called B-DNA. I don’t know what the B stands for, but almost all DNA looks like this, so I’m guessing it’s Boooo-ring.

Moving on to something sexier.

A-DNA is similar to B-DNA structurally; they’re both wound in a “right-handed” orientation, and spoon together like desperate freshmen on a third date. But A-DNA is scrunched up even tighter, like an overwound Slinky. That’s not especially surprising, because you only see this form in DNA that’s dehydrated. I don’t know how your last hangover felt — but twisted up, jumbly and curled in on yourself is probably not a bad description. That’s probably why they call this A(lcohol-soaked-bender)-DNA.

But it gets even weirder.

The third form of naturally-observed DNA is called Z-DNA, and it’s pretty freaky. Like, up is down and right is left and Team Edward and Team Jacob living together in sparkly harmony freaky. First of all, it’s not right-handed. The two strands flip directions and twist the other way around each other, like some genetic freakshow oozing out of Ned Flanders’ Leftorium.

Z-DNA is also ganglier than the other forms, twisting every two base pairs instead of one. It’s not a great look. And the Z stands for “zig-zag”, which is only about a half-step above naming a DNA confirmation “humpback”. Or “pizzaface”.

In the end, you sort of feel sorry for Z-DNA. It looks like some kid accidentally broke a real DNA molecule and tried to rubberband and bubblegum it back together, but there are pieces left over and none of the cracks line up right. It’s the Steve Buscemi of the deoxyribonucleic acid world.

But don’t feel too bad for Z-DNA. Despite it’s lopsided ugly-lefty-ducklingness (or maybe because of it), Z-DNA may actually turn out to be pretty important. Scientists are still exploring its role in biology, but it’s thought that regular old B-DNA can somehow drunken-Twister itself backwards into Z-DNA at spots where transcription occurs in the genome. And since transcription is where the DNA template gets read as RNA, which then becomes the proteins that every cell needs to survive, that’s kind of a big deal. If not for this temporary unwinding into Z-DNA, all our DNA might scrunch up together, winding tighter and tighter like a raging genetic-scale hangover. Even tequila shooters can’t hurt you that bad.

So we should all appreciate our letter-coded DNA double helix friends. B-DNA, steady and boring and essential — the plain white underpants of our genetic material. And A-DNA, which reminds us to hydrate at parties, and also not to get too wound up over things. But especially Z-DNA, the southpaw oddball of the group. Z-DNA demonstrates that even the strangest-looking among us have a role to play, and no matter how weird left-handed people are, we shouldn’t kick them out of the nucleus.

Also, we shouldn’t feed them through a wood chipper, probably. But it is about time to watch Fargo again on Netflix. Thanks, Z-DNA!

Actual Science:
Tulane University – DNA Structure
UCDavis BioWiki – B-form, A-form, Z-form of DNA
UniSci – Left-handed DNA seen to be biologically important
Arizona State University – Virus researchers close in on the secret life of DNA
io9 – Ten things you probably didn’t know about DNA

Image sources: Neuroscience News (“Now I know my A, B, Z…), Nothing Is Going to Last (nailed-in jigsaw piece), Leftorium.com (Leftorium, the store), Dawson Reviews (gimme Buscemi)

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Nanoparticles


· Categories: Physics
What I’ve Learned:

Nanoparticles: Itsy bitsy teeny weeny hella useful science thingies.
“Nanoparticles: Itsy bitsy teeny weeny hella useful science thingies.”

Nanoparticles are little itty bitty things — anywhere from one to one hundred nanometers in size. A nanometer is defined as one billionth of a meter, which is a very European way of saying you can’t see a thing that small, even if you squint.

If you’re having trouble visualizing nanoparticle scale — which is perfectly understandable, since I just told you it’s impossible — maybe this will help: a human hair is roughly 100,000 nanometers wide, or a thousand times bigger than the biggest nanoparticle.

So take some 200-pound person and then think of an animal a thousand times smaller, or roughly three ounces. Like a baby kitten, or a newborn raccoon. Or Ariana Grande. That critter has hair the width of a nanoparticle.

Okay, that’s not actually how hair works. But we’ve established nanoparticles are small. Even compared to squeaky pint-sized pop divas. Which is impressive in itself.

But nanoparticles aren’t just tiny; some of them can also get pretty weird. The physical properties of nanoparticles are impossible to predict, because they’re small enough to feel quantum effects. And everything at the quantum level is weird.

So nanoparticle gold in solution changes color to look black or red. It also melts at much lower temperature. Some nanoparticles absorb radiation (like zinc oxide and UV rays) much better than bigger, beefier versions of the same material. And some magnetic nanoparticles will flip-flop the direction of their magnetism — which is a cute trick for dinner parties, but is pretty lousy if you want to be used for anything practical.

There are all sorts of other complicated things that happen with nanoparticles, most of which sound like they’re from science fiction. Some semiconductors display quantum confinement, which I assume has something to do with how Han Solo got encased in carbonite. There’s also something called surface plasmon resonance, and another called superparamagnetism. Maybe you get those when you’re bitten by a radioactive spider. I don’t know.

Meanwhile, some nanoparticles are incredibly useful, and the basis for whole areas of modern science. In medicine, researchers are exploring using them to deliver vaccines and drugs and detect cancer. Silver nanoparticles in fabrics kill bacteria. Environmental scientists take advantage of certain nanoparticles’ super-reactivity to clean up oil spills and other dangerous pollutants. Plus a thousand other things, like quick-charge batteries and thermal cloaks. Seriously.

And that’s before you even get to the most famous and ridiculously awesome nanoparticle: carbon nanotubes.

Carbon nanotubes are basically straws made of carbon atoms. They can be grown incredibly long (for their nano-sized widths), in a bunch of different configurations, and they’re basically tiny little superhero molecules. Carbon nanotubes are the strongest and stiffest materials currently known, some are harder than diamonds, better thermal conductors (along the straw length) than copper, and possibly (but possibly not) superconductors.

Obviously, scientists want to use carbon nanotubes for basically everything — and they’ve already started. Today, carbon nanotubes are mixed into materials to provide extra strength or other properties, but tomorrow? Synthetic muscles, maybe. Prosthetic retinas for the blind. Space elevators. The sky — or space, actually — may be the limit, when we’ve learned more about carbon nanotubes, and nanoparticles in general. Even if you can’t see them coming.

Actual Science:
Bristol University – What makes nanoparticles different?
Wired – Why Google’s cancer-detecting pill is more than just hype
MIT News – Pills of the future: nanoparticles
IEEE Spectrum – Nanoparticle reduces charge times for Li-ion batteries from hours to minutes
HowStuffWorks – How nanotechnology works

Image sources: AZO Nano (nanoparticles), The Hits (la petite Grande), Wookieepedia (Hansicle), Gizmodo (space elevator [not made of carbon nanotubes, sure, but hey, it’s cool])

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