Speed and power have long been the most important criteria when judging a supercomputer's worth as a number-crunching lab workhorse, but energy efficiency is fast catching up . The greenest supercomputers are those that can process the most scientific calculations per second while drawing the least power. [More]

The 100-plus researchers who set out earlier this year on the biggest scientific twister hunt in history have returned with few tornado tales to tell. [More]

Scientists have discovered a unique "DNA signature" in human sperm, which may act as a key that unlocks an egg's fertility and triggers new life.

Ever since graphene was discovered in 2004, this one-atom thick, super strong, carbon-based electrical conductor has been billed as a “wonder material” that some physicists think could one day replace silicon in computer chips. But graphene, which consists of carbon atoms arranged in a honeycomb lattice, has a major drawback when it comes to applications in electronics – it conducts electricity almost too well, making it hard to create graphene-based transistors that are suitable for integrated circuits. Now a condensed-matter physicist explains how the discovery of graphane, an insulating equivalent of graphene, may prove more versatile still.

In their most recent experiments with Geobacter, the sediment-loving microbe whose hairlike filaments help it to produce electric current from mud and wastewater, scientists supervised the evolution of a new strain that dramatically increases power output per cell and overall bulk power. It also works with a thinner biofilm than earlier strains, cutting the time to reach electricity-producing concentrations on the electrode.

With a novel therapeutic delivery system, scientists have successfully targeted a protein that is over-expressed in ovarian cancer cells. Using the EphA2 protein as a molecular homing mechanism, chemotherapy was delivered in a highly selective manner in preclinical models of ovarian cancer.

A tool bag lost by a spacewalking astronaut in November appears to have met its end after more than eight months in orbit. The chief scientist at NASA's Orbital Debris Program Office says the tool kit should have reentered the atmosphere this morning. "We are waiting on a post-reentry assessment of time and location," to be completed later today by military space monitors, says Nicholas Johnson, who is based at NASA's Johnson Space Center in Houston. [More]

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This is a world you have never seen before, a world normally hidden under miles of water...the landscape of the ocean bed. Click to learn more www.natgeotv.com/draintheocean

French researchers are reporting the existence of a new human immunodeficiency virus (HIV) derived from gorillas in a patient from the African country of Cameroon.

A new study looks at how children perceive and interact with peers who have various undesirable characteristics, such as being overweight or aggressive. The researchers' study explored children's perceptions of the ability of the peer to control or change such traits.

Results of a long-awaited study of 3,070 American adults show that treatment with either of the two standard antiviral drug therapies is safe, and offers the best way for people infected with hepatitis C to prevent liver scarring, organ failure and death.