Physics comes down to Earth

A PIECE OF technology originally designed for a satellite mission to Mars may soon provide a new service – diagnosing tuberculosis in the developing world. This is but one example of how high-tech developments in physics are finding their way into down-to-Earth applications.

Many more examples will be discussed from tomorrow evening in Wexford at the 38th annual “Spring Weekend” organised by the Irish chapter of the Institute of Physics (IoP). They match this year’s theme for the meeting, “Physics for Life”, says IoP representative in Ireland, Alison Hackett.

“The idea is to get physicists and their families and those interested in physics into a social and academic setting,” she explains. The atmosphere is meant to be relaxed yet engaging and the general public are more than welcome to attend, she adds.

It kicks off tomorrow night with a physics pub quiz at the venue, Whites Hotel in Wexford. The programme on Saturday includes a number of talks by local and international speakers on a range of subjects.

And on the Sunday, physics stalwart and co-founder of the BT Young Scientists and Technology Exhibition, Dr Tony Scott, will conduct television-style interviews with four Irish-based physicists, asking them how they got into physics and about the latest discoveries being made in

astro-nomy, particle physics, quantum physics and climate change.

Examples of how advanced physics-based technologies are helping human health will be presented on Saturday by guest speaker Prof Louise Harra of the department of space and climate physics at University College London. Originally from Armagh, she plans to discuss how a miniaturised mass spectrometer designed for a mission to Mars for analysing the chemical composition of substances is being modified for use in medical diagnosis.

"They are developing it so it can become a hand-held [device] for picking up TB," she told Science Today. It is being reconfigured to recognise a breath-borne chemical signature for the disease, and should give quick, cheap and early diagnosis of TB.

Prof Harra will also describe how a laser originally built to measure ozone in the upper atmosphere has been redeveloped for use as an alternative to the heart treatment angioplasty.

The treatment uses something akin to a narrow balloon, inflated to increase the flow through blood vessels narrowed by hardening of the arteries. The new technique uses a laser beam instead to obliterate these plaque deposits, Prof Harra says.

Thin fibre-optic cables are used both to provide a live picture of the blockage and also to deliver the laser beam that clears the deposits. As with conventional angioplasty, no surgery is required as the fine cable is introduced and guided to its destination through a vein.

A third example involves reapplying the highly sensitive optical technology that allows the Hubble Space Telescope to “see” all the way to the edge of the universe, used to help in the diagnosis of breast cancer.

The faint light from distant stars is picked up by Hubble using charge-coupled devices (CCDs). This CCD technology is “very, very sensitive”, and is used to help identify the precise location where a surgeon can capture a minute sample of tissue for analysis, she says.

Other speakers include Dublin City University’s Prof Brian MacCraith, who will talk about medical diagnosis using optical “biochips”, and Trinity College Dublin’s Prof Martin Hegner, who will discuss how minute “optical tweezers” can be used to manipulate a single biomolecule.

For the past two years, the Spring Weekend has also included a poster competition for postgraduate students who are asked to produce poster displays explaining their research work. The winner receives the Rosse Medal, a solid silver award struck to celebrate the Third Earl of Rosse, William Parsons, who built the “Leviathan” telescope at Birr, Co Offaly.

The Spring Weekend is open to the public, with full weekend registration costing €90 for non-IoP members. Single day registration costs €45. For more information, see www.iopireland.org.