MP Evan Harris is one of 18 volunteers for HIV vaccine trials

England have

The World Aids Conference in South Africa has announced trials for a new HIV vaccine will begin in Britain.

Liberal Democrat MP Evan Harris will be one of 18 healthy volunteers who will take part in the first toxicity tests.

The MP for Oxford West, Dr Harris, 35, said: "I hope to be a small part of a process that will deliver something that will save Africa from further devastation."

The vaccine has been developed by researchers at Oxford and Nairobi Universities who studied prostitutes in Kenya and found a group who resisted the disease in spite of daily exposure to it.

If the tests in Oxford are successful, trials will go to Nairobi in October under the supervision of Professor Job Bwayo and his team.

Professor ofimmunologyat Oxford University Andrew McMichael said: "Our chances of developing a vaccine are better than 50-50. But the earliest we could expect a vaccine to be ready would be in seven to 10 years."

There are currently 34 million people in the world suffering from HIV and 70% of them are in Africa.

This is the first time a vaccine has been based on the HIV strain in Africa. It uses DNA and a wild animal virus similar to that used to combat smallpox.

The Oxford-Nairobi project is one of 11 similar groups around the world funded by the International Aids Vaccine Initiative (Iavi). It has received ?4m from the British Government.

Iavi estimates that three times more than the ?00m currently spent on research programmes is needed to find a vaccine within ten years.

Vaccination should provide a much cheaper and more effective means of tackling the pandemic, especially for the Third World which cannot afford HIV drugs and is barred from developing generic variations.

According to Iavi only 2% of the $20m spent annually on Aids around the world is for vaccine development.

Skylab I was launched on 14 May 1973

All week there has been mounting speculation over where the spacecraft would come down. It has been in orbit six years - for the past five of those it has been unoccupied.

Skylab's last signal was recorded at 1611 GMT. Less than an hour later a tracking station at Ascension Island in the South Atlantic confirmed the solar panels were beginning to peel off as the craft descended.

The 77.5 ton Skylab could break into as many as 500 pieces, including a 5,100lb (2,310kg) airlock shroud and a 3,900lb (1,767kg) lead safe to protect film from radiation, which are expected to survive the heat of re-entry into the earth's atmosphere.

Head of the Nasa task force monitoring Skylab, Richard Smith, said they had already received reports of hot debris, which had lit up the night sky, from several points in Western Australia.

'Edge of Cornwall'

Dozens of residents reported seeing debris falling near Kalgoolie, 370 miles (595km) northeast of Perth.

Skylab was launched on 14 May 1973 and was lived in by three teams of astronauts for periods of up to 84 days as they tested human endurance over long periods of weightlessness.

While the astronauts were on board they were able to carry out many valuable scientific experiments including analysis of the sun's activity and how it affected the Earth.

Skylab was abandoned by the last crew in February 1974, since when scientists have only had limited control over it. It was supposed to stay in orbit until the mid-1980s when the new shuttle would have come to its rescue.

A Skylab task force of computer specialists, engineers, lawyers and public relations experts has been on standby at various Nasa centres.

It has been very difficult to predict exactly where and when the craft would finally come down. Only two days ago, a Nasa spokesman had been predicting it would land near the "edge of Cornwall".

In India, the police in all 22 states were put on full alert and the civil aviation department was planning to ban flights across the sub-continent during the crucial hours of re-entry.

Skylab's final orbital path, its 34,981st, passed over the north Pacific, the northwest tip of the United States, south central Canada, north of Montreal and Ottawa and the state of Maine.

immunology :免疫學(xué)