Tag Archives: science

Blog

Climate change might not starve us after all

3 Comments

oatsIn the hugely polarised sphere of debate around climate change, there are a few thinkers who float outside the two core camps of belief and skepticism. One of those would be Brian Wang, who seems pretty convinced that AGW is a genuine phenomenon, but who also thinks it’s not going to be an unmitigated disaster. For example, he has a post responding to suggestions that a global temperature increase would lead to mass famine and starvation, in which he lists currently available or imminent technologies and scientific developments that could cope with the changed climate and keep the planet’s belly full. [image by sarniebill]

Of course, it’s worth remembering that a large percentage of the Earth’s population doesn’t have enough to eat already… and that a small percentage consumes way more than it actually needs. Keeping up production levels will be important, sure, but efficient and fair distribution of food resources would go a long way toward helping us ride out the rough patch. But then the same applies to energy resources, and we’ve already seen how popular the redistribution idea is with those who have the most to lose…

[ Feel free to discuss Wang’s points in the comments, but as always with this sort of post, unqualified trumpeting of ideologies from either side of the fence will be deleted without prejudice – that applies to climate change denial and climate change doomsaying. I have better things to do than referee an unwinnable slapfight, I’m afraid, so check the comments policy before you post. ]

Blog

Microfluidic diagnostic chips are (almost) child’s play

1 Comment

Pity us poor Brits and our ox-bow lake of eighties pop-culture – until today I had no idea what Shrinky Dinks were. But now I know… and I also know that code 6 polystyrene sheets (which is what Shrinky Dinks are made of) can be used to make single-run prototypes of microfluidic diagnostic chips, thanks to the innovative thinking of one Michelle Kine:

… she whipped up a channel design in AutoCAD, printed it out on Shrinky Dink material using a laser printer, and stuck the result in a toaster oven. As the plastic shrank, the ink particles on its surface clumped together, forming tiny ridges. That was exactly the effect Khine wanted. When she poured a flexible polymer known as PDMS onto the surface of the cooled Shrinky Dink, the ink ridges created tiny channels in the surface of the polymer as it hardened. She pulled the PDMS away from the Shrinky Dink mold, and voilà: a finished microfluidic device that cost less than a fast-food meal.

[…]

She hastens to point out that Shrinky Dink microfluidics isn’t perfect–minute ink splatters from the printer, for instance, can give rise to slight irregularities in the finished channels.

Still, glitches like these don’t pose a problem for most applications. And Khine has already found a way around a more serious difficulty: PDMS can absorb proteins, throwing off the results of sensitive tests. She has begun to make chips directly out of the Shrinky Dinks by etching the design into the plastic using syringe tips. As the plastic shrinks, the channels become narrower and deeper–perfect for microfluidics. She can even make three-dimensional chips by melting several etched Shrinky Dinks together. The whole process, from design to finished chip, takes only minutes.

Kudos, Miss Kine. Even if you’re not a microfluidics researcher, this is an impressive example of finding cheap methods for making high-tech devices – the sort of favela-budget hack that takes a technology from university laboratories to the potting sheds of the globe. I wonder what the garage biohacker crowd will make of Kine’s innovation? And what might be the next lab-grade technology to be reproduced at a fragment of the normal price using off-the-shelf stuff from the supermarket? [via BoingBoing]

Blog

Natural nuclear reactors

5 Comments

My magical statistics monkeys tell me that last week’s post on dissociative fugues was surprisingly popular, so I thought I’d share another article I found fascinating. Yet another hat-tip to Geoff Manaugh at BLDGBLOG for this one; it’s a Scientific American report on naturally occuring nuclear reactors. Yes, you read that right – nuclear power plants that just happened by geological chance.

More than two tons of this plutonium isotope were generated within the Oklo deposit. Although almost all this material, which has a 24,000-year halflife, has since disappeared (primarily through natural radioactive decay), some of the plutonium itself underwent fission, as attested by the presence of its characteristic fission products. The abundance of those lighter elements allowed scientists to deduce that fission reactions must have gone on for hundreds of thousands of years. From the amount of uranium 235 consumed, they calculated the total energy released, 15,000 megawatt-years, and from this and other evidence were able to work out the average power output, which was probably less than 100 kilowatts—say, enough to run a few dozen toasters.

(Or a few dozen highly-efficient computers, perhaps?)

It is truly amazing that more than a dozen natural reactors spontaneously sprang into existence and that they managed to maintain a modest power output for perhaps a few hundred millennia. Why is it that these parts of the deposit did not explode and destroy themselves right after nuclear chain reactions began? What mechanism provided the necessary self-regulation? Did these reactors run steadily or in fits and starts?

Go read the whole thing; the science isn’t too heavy, and it’s a pretty wild idea. I’m pretty sure I’ve read about something similar in a Stephen Baxter novel (though I can’t for the life of me remember which one); at the time I assumed he was speculating in a vacuum, but I guess I should have known better. 🙂

Regarding the popularity of the dissociative fugues post, I’ve been wondering whether perhaps I should be spending more time linking to interesting stuff and less time waffling around on tangents? It’s you guys who read this stuff, so what would you like to see here – more random points of interest, more speculative ramblings, or a blend of the two?

Blog

New nanoparticle self-assembly routes “more like nature”

Here’s the latest on new techniques in nanoparticle self-assembly as discovered by researchers from the US Department of Energy:

“We’ve demonstrated a simple yet versatile approach to precisely controlling the spatial distribution of readily available nanoparticles over multiple length scales, ranging from the nano to the macro,” says Ting Xu, a polymer scientist who led this project and who holds joint appointments with Berkeley Lab’s Materials Sciences Division and the University of California, Berkeley’s Departments of Materials Sciences and Engineering, and Chemistry. “Our technique can be used on a wide variety of nanoparticle and should open new routes to the fabrication of nanoparticle-based devices including highly efficient systems for the generation and storage of solar energy.”

Well, that’s the sales pitch out of the way. The thing that caught my eye about this particular piece, though, was this paragraph:

“Bring together the right basic components — nanoparticles, polymers and small molecules — stimulate the mix with a combination of heat, light or some other factors, and these components will assemble into sophisticated structures or patterns,” says Xu. “It is not dissimilar from how nature does it.“

Now, think back to that video of DNA and RNA synthesising proteins like tiny little machines… as we get closer and closer to mastering matter at an atomic level, will the line between “life” and “machines” become increasingly meaningless?