August 07, 2008

Technology News roundup: Vasimr rocket, $12 PC, $10 microscope, better biomass

This technology news roundup has imminent testing of the Vasimr plasma rocket in space, twelve dollar personal computers, ten dollar dime sized microscopes and a plant that is 250% better than corn for biofuels and twice as productive as switchgrass. (the plant has not been modified yet and genetic modifications could vastly increase yields.)

Nasa will be testing the Vasimr plasma rocket soon on the International Space Station. The 200KW Vasimr was covered here in April 2008

A group of people attending the MIT International Development Design Summit are working to make a $12 computer based on the Apple II. These include, clockwise from front left, U.S. graduate student Derek Lomas, Anuj Nanavati of India, MIT graduate Jesse Austin-Breneman.

Imagine a microscope implanted into your body that could automatically sort out cancerous cells based on how they looked. That's the long-term promise of a lensless microscope that Caltech researchers describe this week in the journal Proceedings of the National Academy of Sciences.

Exploiting technology commonly used in consumer digital cameras, the M&M-size microscope is able to provide resolution comparable to an optical microscope at a mere fraction of the cost, perhaps as cheaply as $10 per unit.

"Microscopy is undergoing a great revolution now because of modern optics and spectroscopy," Feld said. "There are many exciting new approaches and this is one of them."

But Yang's tiny, cheap microscope could have nearly immediate applications. In the very short-term, Yang envisions a system for identifying diseases in the Third World that could cost a mere $100 and come embedded inside a cellphone or custom device for field work. "Because we can build [the microscope] very compactly, we can imagine building an entire system that is the size of an iPod," he said.

All of these applications could come into being very soon. Yang's lab is currently negotiating with semiconductor companies to mass produce his devices. Right now, it takes two days for one of his grad students to assemble one.

Once they enter manufacturing, however, they'll be able to make hundreds of the devices, and that's when high-throughput optical microscopy could become a reality. Working with image processing software designers, they're hoping to come up with autonomous systems for finding ad imaging cells.

Researchers have determined that an acre of the giant perennial grass Miscanthus x giganteus makes 2 1/2 times the amount of ethanol we can produce per acre of corn.

“One of the criticisms of using any biomass as a biofuel source is it has been claimed that plants are not very efficient – about 0.1 percent efficiency of conversion of sunlight into biomass,” Long said. “What we show here is on average Miscanthus is in fact about 1 percent efficient, so about 1 percent of sunlight ends up as biomass.”

“Keep in mind that this Miscanthus is completely unimproved, so if we were to do the sorts of things that we’ve managed to do with corn, where we’ve increased its yield threefold over the last 50 years, then it’s not unreal to think that we could use even less than 10 percent of the available agricultural land,” Long said. “And if you can actually grow it on non-cropland that would be even better.”

“Our highest productivity is actually occurring in the south, on the poorest soils in the state,” he said. “So that also shows us that this type of crop may be very good for marginal land or land that is not even being used for crop production.”

Because Miscanthus is a perennial grass, it also accumulates much more carbon in the soil than an annual crop such as corn or soybeans, Long said.

“In the context of global change, that’s important because it means that by producing a biofuel on that land you’re taking carbon out of the atmosphere and putting it into the soil.”

“One reason why Miscanthus yields more biomass than corn is that it produces green leaves about six weeks earlier in the growing season,” Long said. Miscanthus also stays green until late October in Illinois, while corn leaves wither at the end of August, he said.

Using corn or switchgrass to produce enough ethanol to offset 20 percent of gasoline use – a current White House goal – would take 25 percent of current U.S. cropland out of food production, the researchers report. Getting the same amount of ethanol from Miscanthus would require only 9.3 percent of current agricultural acreage.