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The United States is expected soon to establish its Department of Homeland Security. The precise threats facing the nation are uncertain, but challenges in its preparedness to deal with attacks on health and agriculture are all too obvious.
A new Department of Homeland Security is to be given the task of defending the United States against further terrorist attacks. Geoff Brumfiel outlines the challenges facing its research wing.
Particles with hundreds of millions times more energy than those in physicists' accelerators regularly strike the Earth, but no one is sure where they come from. Philip Ball reports on attempts to solve the mystery.
Drugs that keep the blood circulation flowing help to prevent heart attacks and strokes caused by clots in the wrong places. A new anti-clotting tool is now revealed, along with its antidote.
The Universe is made of matter, not antimatter, and 'CP violation' in particle decays could be the reason. Results from experiments measuring this effect at last confirm the predictions of a 30-year-old theory.
When our cells divide, they are cut down the middle by a tightening belt of proteins. New work reveals that the protein filaments in this belt are made from scratch every time.
How do crystal structures terminate at 'flat' surfaces? New developments in electron crystallography mean that the detailed atomic structure of surfaces in complex crystals can be determined — with surprising results.
When faced with foreign molecules our antibodies mutate, allowing them to bind to the intruders more strongly. In a story full of surprises, it looks as though the mechanism of mutation has finally been revealed.
The Earth's crust can deform catastrophically in earthquakes, but it's difficult to predict exactly what causes such failure. Analysing thousands of small shocks might help us better understand how earthquakes occur.
