when the status quo frustrates.

This Is So Much Better Than My Undergrad Intro to Engineering Project

Tuesday, July 20th, 2010

…but to give me credit where credit is due, the problem posed to us by our instructor was a lot less interesting, too. As I recall, he had us come up with something you could put on your shoes to prevent slipping on an icy sidewalk. The constraints were the same, though, in terms of cheap household objects etc.

The coolness:

Rice University undergraduates Lila Kerr and Lauren Theis were presented with an assignment in their Introduction to Bioengineering and World Health class. As Theis explains:

“We were essentially told we need to find a way to diagnose anemia without power, without it being very costly and with a portable device.”

In a solution short on cost but long on ingenuity, the duo modified a basic, every day salad spinner into an easy to use and transport centrifuge that successfully separates blood to allow diagnosis of anemia with no electricity. The device costs about $30, can process 30 individual 15 microliter blood samples at a time, and can separate blood into its component red cells and plasma in about 20 minutes.

More Outer Space Coolness

Tuesday, June 30th, 2009

Literal coolness, given that we’re talking about a moon of Saturn. Water is amazing stuff from a chemical, physical and even biochemical standpoint–unique on multiple levels, absolutely required in liquid form to sustain any life that we could ever really recognize as such.

I’ve been a big fan of Jupiter’s moon Europa for years–looks like I have another gas giant moon to add to my list!

The Salty Waters of Saturn’s Moon Hint at Life


A Cassini spacecraft image shows icy geysers spewing from the south polar region of Saturn’s moon Enceladus. The salt particles in the ice jets are the strongest evidence to date of a liquid ocean under the moon’s icy crust.

Sex 2.0! Part Three: Ethical Research

Tuesday, May 12th, 2009

(Parts One and Two are here and here.)

Being something of a scientist, and living in a society that revels in its hierarchy and is constantly looking for ways that at least appear objective to justify it, I’ve struggled with this issue before. It was interesting to see it come up at Sex 2.0, and hear an actual professional researcher tackle it.

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Exploding glass tears.

Thursday, February 5th, 2009

Today was Fun Physics Day at work, as often happens the afternoon after a whole morning is killed by meetings. I have no idea how we got on the subject, but today’s project ended up being Prince Rupert Drops. Prince Rupert Drops are tear-drop shaped glass balls with long, trailing tails. The base of the bulb is shockingly strong, but the tail can be snapped fairly easily. When this happens, the entire drop explodes into a fine dust. The short explanation:

When molten glass hits cold water, its outer surface cools rapidly and shrinks as it solidifies. Since the center is still fluid, it can flow to adjust to the outer shell’s smaller size. As that center eventually cools and solidifies, it also shrinks, but now the outer shell is already solid and can’t change its shape to accommodate the smaller core.

The result is a great deal of internal stress, as the center pulls the outside in from all sides. Like a tightly wound spring, the glass is set to release a lot of energy. If you break the thin glass at the tail, a chain reaction travels like a shock wave through the drop. As each section breaks, it releases enough energy to break the next section, and so on, shattering the whole drop in less than a millisecond.

Paradoxically, the same tension also makes the Prince Rupert’s drop stronger. Glass breaks when tiny scratches pull apart and spread into fractures. Since the surface is compressed by internal stress, scratches can’t grow, and the glass is very difficult to break.

A professor at Purdue University clocked the fractures at over 4,000mph. Unfortunately my university doesn’t carry the journal he published in, so I don’t have anything more than that abstract to share.

My coworkers made about 5 of these things using glass stirring rods, pipettes, and an ordinary propane torch, although it was a massive pain in the ass. It took forever, and not every tear-shaped glass drop is a Prince Rupert Drop. But when it works, it’s fantastic. My coworker said it felt like a bomb going off in his hand when our drop became a rough silt. It’s also possible to make the tail too fine, so that you have to snap off more than one section to get the explosion. The explanation I read, that I can’t seem to find right now, suggested that the diameter of the glass has to be sufficiently large to allow the cracks to propagate, i.e. if you snap too thin a piece off, the rest of the structure can just shrug it off. If you’ve got a nice traily tail, this means you can flirt with danger by flicking at the flexible bit at the end and dramatically snapping off several pieces before the whole thing disintegrates. Of course, you’d have to play with a lot of them before you got a feel for where that point is.

You can also make your own glass fibers by heating the middle of a glass rod until it softens and glows red, then removing it from the flame and pulling really fast. If your rod was solid, you’ve just made a fiber optic cable. If your rod was a tube, you now have a very small capillary tube.

Outer Space is So Awesome

Thursday, July 31st, 2008

Titan seen from outer space

Surface of Titan

NASA says liquid confirmed on Saturn’s moon Titan

PASADENA, Calif. (AP) — At least one of many large, lake-like features on Saturn’s moon Titan studied by the international Cassini spacecraft contains liquid hydrocarbons, making it the only body in the solar system besides Earth known to have liquid on its surface, NASA said Wednesday.

Scientists positively identified the presence of ethane, according to a statement from NASA’s Jet Propulsion Laboratory in Pasadena, which manages the Cassini mission exploring Saturn, its rings and moons.

Mars seen from outer space

Surface of Mars

NASA probe confirms water on Mars

LOS ANGELES (AFP) — NASA scientists said Thursday the Phoenix lander exploring Mars had confirmed water on the planet after analysis of a soil sample from the Red planet’s surface.

The discovery was made after the lander’s robotic arm delivered a sample this week to an instrument onboard the lander that identifies vapors through heating samples.

“We have water,” said William Boynton of the University of Arizona, lead scientist for the lander’s “oven” Thermal and Evolved-Gas Analyzer, or TEGA.

“We’ve seen evidence for this water ice before in observations by the Mars Odyssey orbiter and in disappearing chunks observed by Phoenix last month, but this is the first time Martian water has been touched and tasted.”

I Really Like Other Planets

Wednesday, June 25th, 2008

Water ice and evidence of historic rainfall on Mars.

Smaller, rocky exoplanets near the habitable zone around their stars are being found. For a totally awesome exoplanet slideshow, click here.

(Because I need to think about something other than people right now. Ugh!)

See you in August

Sunday, June 1st, 2008

Well guys, I’m out for the summer. Tomorrow I leave for Europe. In our group meeting last week, my coworker said he finally figured out the pattern: every summer, my boss goes on tour, like a rock star. He has probably half a dozen countries to visit in the next two months, where he’ll give presentations and invited talks and most importantly, play in what I think is some sort of world championship soccer game where all the soccer players are world-renowned academics. This year, he scattered roadies all over Europe, and I make up the Western Europe crew; then we’ll meet up rather in the center, depending on how much of the CIS you count as Europe. I have two mandates; one – get enough research done in three weeks on a topic that I know next to nothing of to eek a somewhat credible paper out of, and two-have fun.

If I have any particularly hilarious adventures, I’ll drop by, but otherwise, you can enjoy a nice Kyso break and focus on all the Lisa, Violet, Antigone and Sabbotabby goodness you can handle.

I Like Other Planets

Sunday, May 25th, 2008

Seriously, I had all the ones in the Solar System memorized when I was six years old. Yeah, back when Pluto (a) was not only a planet but the smallest planet and (b) didn’t have a moon, and when Jupiter only had 9 moons and Saturn only had 12 moons…oh, those were the dayz…

Of course I realized by age 12 that people who got carsick riding to Grandma’s house probably weren’t cut out to be astronauts, so that killed THAT dream (sadness!). However, it didn’t kill my fascination with all things extraterrestrial, with the sole exceptions of crop circles and Scientologists.

So here I am Sharing Teh Awesome outer-space news. Enjoy!

The first-ever landing of a probe near Mars’ north pole happened smoothly on Sunday, NASA confirmed.

Aww Baybeez!

Monday, May 19th, 2008

My twin sibblings
Cute little devils, aren’t they.

So I was talking to my ex-husband the other day, and I was asking him how his new baby was doing (he just got remarried about a year ago) and he said she was fine, and then he said, “You know, she’s so sweet.”

“Aww,” I said, cause it was expected of me, and also, she really is a cutie–I ran into her and her mom at the grocery store the other day.

“Girls really are different,” he continued on enthusiastically. (He and I have two boys together.) “I mean, right from the beginning. They’re just so much, you know–”

“Girlier?” I suggested.

Some dryness may have been apparent in my tone, because he immediately began elaborating–”Just, gentler. And just daintier. And calmer, you know?”

I had no interest in debating his assertions–she’s his new baby, I’m not gonna argue with that kind of infatuation! And I don’t know the specific kid beyond a few brief encounters. But after we exchanged a few more pleasantries and hung up, the conversation returned to me and got me thinking…is there really a perceptible difference, on any level other than genital, between girl and boy babies? Especially girl and boy babies that young?

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Silly putty is viscoelastic

Thursday, December 20th, 2007

I promised you guys a polymer lecture, and I had a good boring one about polymer stabilized systems all mapped out in my brain. Lucky for you, I spent the day engaged in some very cutting-edge research on polymers, or at least that’s how we explained it to our boss when he came into the lab and found us examining the flow properties of silly putty. We’d had two samples of silly putty running down a filing cabinet for almost a month, and were analyzing the data. So let’s talk about silly putty instead.

Silly putty is a great polymer with a bunch of science packed into it. Silly putty is one of those accidental inventions, the by-product of war-era research on synthetic rubbers. While the story goes that the inventor sent samples of his bizarre polymer to scientists all over the world and none of them could think of a damn thing to do with it, I suspect they weren’t even trying. Most scientists when given an object will immediately spew out six different applications they’d like to apply it to, of which one might work and if we’re lucky won’t be prohibitively expensive. Either way, the entrepreneurs persevered by realizing that just because something is impractical doesn’t mean people don’t want it and today silly putty is not only a popular toy, but has found plenty of applications.

Silly putty’s weirdness stems from it’s odd flow properties: it bounces like a rubber ball, but can be smushed easily if pressed slowly. Some materials react differently to stress depending on how quickly the stress is applied. This is called a ‘viscoelastic’ response, where visco = flowy and elastic = bouncy. Most things give you a choice, either or but not both, but silly putty is in a special catagory of materials that can do both, depending on how you poke them.

“Quickly” is a relative term, and part of learning to be a scientist is learning how to combine a bunch of material parameters and spit out a decent time scale. Silly putty happens to have a very human-friendly natural relaxation timescale where shocks that are quick to us (bouncing, hammering) are also quick to the putty and slower but people-friendly stresses like kneading are slow enough to cause the flow response. Some materials that flow, like glass (which is not in the same family of materials as silly putty at all), flow so slowly that you wouldn’t notice a difference if you had a dozen lifetimes to sit there and watch,so we can pretty much always treat them as a solid. I’ve heard that stained glass windows in old-school European cathedrals are supposed to be almost imperceptibly thicker towards the bottom, and that this has been attributed to glass flowing downward under the influence of gravity, but at least one of my professors believes that this famous and fun example is probably a load of crap. I’ve never sat down and done the math myself, so I have no idea if hundreds of years is enough time to notice a difference. Point is, how long it takes a material to respond to different forces can be very important when it comes to considering how and if you can use it in a particular application, and silly putty might not be as fun if it had a different relaxation time.

There is a very good PDF on this topic over at the Cambridge Polymer Group’s website, including pictures of a sheet of silly putty with a bullet going through it. Also of note is this experiment where 50 pounds of silly putty were dropped off a parking garage.

You can make silly putty very easily at home with glue and a few other things, but some recipes involve ingredients that you may not have laying around and I’ve never tried any of the elmer’s glue ones myself so I don’t know how well it would work. A viscoelastic fluid that is easy to make at home and actually a little cooler (but a lot messier) than silly putty is cornstarch and water. Pretend you’re making a thickening agent for stew, but reverse the relative amounts of cornstarch and water so that it is mostly cornstarch. You’ll end up with a material that you can pour from one hand to the other but feels like a brick wall if you slap it. Also it will cover everything it touches in a fine dusting of starch, so tell your kids to keep it outside.

Yet another creepy research study

Monday, November 12th, 2007

Pretend that you’re a journalist for the BBC. You’ve just seen the results of a scientific study on a group of women that shows a correlation between a large hip-to-waist ratio and high scores on cognitive tests. (Ignore, for a moment, the absurdity of doing such a study in the first place.) Now you’re going to report on that study. Which of these angles are you most likely to take?

• Fat deposits aren’t that bad for you: in fact, they may be linked to higher intelligence.
• Diet, which is linked to social class, affects performance on cognitive tests.
• Hey men! Curvy women are smarter. If you have sex with them, they’ll bear you smarter kids, which is apparently the primary purpose of women. Anyway, the main thing is that you don’t need to hide your fetish for chubby chicks anymore. Go get yourself one!

Click for the answer.

The other headlines on that page are also quite telling:

Sexy walks ‘keep men off scent’
Gaze ‘key to facial attraction’
‘Hormonal’ women most attractive
Attraction ‘determined by walk’
Slim waist holds sway in history
Hourglass figure fertility link

No one has anything more important to research or report on? Really?

Hat tip: Jenlight.

Yet another way in which America is screwing Iraq

Saturday, September 22nd, 2007

So we’ve all heard about the Blackwater thing by now, right? After last Sunday, when Blackwater Christofascist mercenaries went on a killing spree, murdering at least 28 people in cold blood, Iraq’s puppet government finally said “enough is enough,” and revoked Blackwater’s license to operate in the country. This isn’t the first time that Blackwater has done something like this—it’s easy, considering that Blackwater killers are immune from prosecution. They’re only killing Iraqis, after all.

Remember democracy in Iraq, and those teary-eyed American conservatives praising the courage of ordinary men and woman and their purple fingers? Well, turns out that the whole democracy-building adventure was as hollow as we anti-war cynics said it was, because despite the puppet government’s orders, the occupiers have resumed Blackwater convoys. This, despite how deeply horrifying the massacre really was:

Witnesses say the first victims of the shootings were a couple with their child, the mother and infant meeting horrific deaths, their bodies fused together by heat after their car caught fire. The contractors, according to this account, also shot Iraqi soldiers and police and Blackwater then called in an attack helicopter from its private air force which inflicted further casualties.

Pretty par for the course, though, burning parents and babies alive. We’re used to hearing news like that. Here’s a fresh new horror that America is foisting on the long-suffering Iraqi people: Order 81.

Most North Americans, even left-wing, anti-capitalist North Americans, don’t know about the epidemic of debt-related suicides among Indian farmers. You should take some time to learn about it, though—at least 4,500 farmers in central India have killed themselves in the past six years—even higher than the slightly-better-publicized 4,300 Palestinian deaths so far during the Second Intifada. And while neoconservatism has generated righteous anger for its genocidal ideology, the Indian tragedy is a reminder of how brutal neoliberalism has been for the people of the Third World.

So, why are the Indian farmers killing themselves? Because they can’t repay crop loans. Why can’t they repay crop loans? Well, the way farming has worked since the dawn of agriculture is that you have your initial investment, which includes seeds, and you keep reusing your seeds after each harvest. If you don’t have enough, you can trade seeds with your neighbour. But companies like the notorious U.S.-based Monsanto realized that they could make more money manufacturing and pushing genetically modified “terminator seeds,” which are sterile and cannot be reused, forcing farmers into dependence on the company for their livelihood. To make things worse, the genetically modified seeds tend to be hardier than the natural variety, so the sneaky company can just blow some onto an unsuspecting farmer’s field, and presto! The mutant crops overtake the natural crops, and you have a new Monsanto customer-for-life. Nice, huh?

Well, this has worked out so nicely for transnational corporations in India that the Americans have decided to try it in Iraq, because invading, murdering, and looting hasn’t permanently screwed the country enough. When he was administrator of the Coalition Provisional Authority, U.S. diplomat L. Paul Bremer issued a bunch of orders, including the aforementioned Order 81:

What Order 81 did was to establish the strong intellectual property protections on seed and plant products that a company like the St. Louis-based Monsanto — purveyors of genetically modified (GM) seeds and other patented agricultural goods — requires before they’ll set up shop in a new market like the new Iraq. With these new protections, Iraq was open for business. In short, Order 81 was Bremer’s way of telling Monsanto that the same conditions had been created in Iraq that had led to the company’s stunning successes in India.

Dr. Vandana Shiva, a scientist and activist who has done a tremendous amount to fight against the GM assault on India, explains the colonialist dimensions of terminator seeds thusly:

This epidemic of piracy is very much like the epidemic of piracy which was named colonialism 500 years ago. I think we will soon need to name this round of piracy through patents as recolonialization as a new colonialization which differs from the old only in this – the old colonialization only took over land, the new colonialization is taking over life itself.

While the Blackwater mercenaries will eventually be forced to leave, one way or another, terminator seeds are a great way to ensure that Iraq will remain, long into the foreseeable future, a wretched neo-colony of American corporations.