Different sorts of viruses have different weights, but all viruses of a particular type weigh the same amount.

ECONOMIST: Small-scale physics

The H5 in H5N1 stands for hemagglutinin type 5, meaning the fifth known type of hemagglutinin found on the coatings of influenza viruses.

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Of the H3N2 viruses tested at that point, 99.4% matched the type that the vaccine protects against.

CNN: Had a flu shot? You'll be OK -- maybe

Meanwhile, Jillian Shapiro of Mount Sinai Medical School figured out away to get another new type of genetic material, called microRNA, into cells using viruses.

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Existing vaccines work against viruses and bacteria, but the parasite that causes malaria is a more complex type of organism.

ECONOMIST: Malaria research gets a shot in the arm

Of the influenza B viruses tested between October 1 and January 5, 66.7% were the type represented in the vaccine.

CNN: Had a flu shot? You'll be OK -- maybe

Anderson said the U.S. may end up with a new type of weaponry for launching massive distributed denial-of-service attacks and computer viruses.

CNN: U.S. Army kick-starts cyberwar machine

Several breakthroughs sent shock waves through the field of renewable energy this week as Inhabitat reported on a new type of "invisibility cloak" that could supercharge solar cells and researchers at MIT harnessed viruses to improve the efficiency of dye-solar cells by a full third.

ENGADGET: Inhabitat's Week in Green: sugar-covered lamps, IKEA's solar lamp, and the 30MPH all-wood racing bike