Invisible circuits top science honours

Tiny molecules form the basis of miniature circuits

		By BBC News Online's Ivan Noble

The top scientific breakthrough of 2001 has been learning to wire up the tiny electronic components created from individual atoms and molecules by nanotechnology researchers.

The journal's cover fetes 2001's top breakthrough
Illustration: Cameron Slayden

So say the editors of the prestigious US-based journal Science, who publish a top 10 list of major achievements at the end of each year.

"The possibilities are remarkable, because the scale is thousands of times smaller than that embodied in the very best contemporary computer chips," they say.

No longer just atomic-scale novelties, nanocircuits have proved themselves capable of carrying out simple computing tasks, the first step towards developing computers so tiny they could float on the wind or swim in the blood.

Genetic advance

Number two on Science's list of breakthroughs is the work done in 2001 on RNA, the single-stranded sister molecule of DNA.

Studies have found RNA to be much more versatile than previously realised and have uncovered a way of switching on and off the operation of individual genes in a cell.

Genes are the codes that control the way all living things grow and live.

The potential for science, and medicine in particular, of knowing how to control them individually is enormous, and the work could help discover just what all those genes found by the human genome project actually do.

The remaining eight breakthroughs share equal honours in the Science top 10:

• Canadian detectives have solved the mystery of the missing neutrinos. For years, the number of these tiny particles streaming away from the Sun has been unaccountably small. Now, it seems they are not just disappearing, but transforming.

• 2000's winners, the genome sequencers, who cracked the human code, were followed in 2001 by researchers who brought the total of organisms decoded to over 60. The year's subjects have included several nasty disease-causing bugs.

• Two new superconductors were found, both working well above the near-absolute zero temperatures needed for the first no-resistance conductors.

• Researchers investigating neurons took a step closer towards understanding how nerve cells link together. The knowledge could help work out how to fix damaged nerves in humans.

• The US authorities approved a new anti-cancer drug, the first of a new breed of smart cancer drugs carefully targeted at the operations of individual cancers. More drugs are undergoing clinical trials.

• The Nobel Prize for physics went to the creators of the first Bose-Einstein condensates. Two teams in France managed to create this new state of matter using helium for the first time.

• Climatologists weighed the evidence and leaned even further towards the conclusion that human activity was responsible for global warming.

• Warring climate researchers arguing about how much greenhouse gas is reabsorbed naturally in the US buried the hatchet and revised their estimates closer to a compromise.

The International Space Station (ISS) makes an appearance, too; not in the list of breakthroughs but of breakdowns.

Science highlights the platform's budget problems as one of the year's major problems, alongside what it describes as a "scientific vacuum" in the US Government.