Chimpanzee waste could shed light on the origins and spread of HIV.

Delving into droppings has given AIDS researchers a surprise. Far fewer chimpanzees than they had suspected have SIVcpz, the animal virus most like HIV.

The technique could shed much-needed light on the origins and evolution of the viruses that cause AIDS. “It’s a non-invasive means to study the wild relative of HIV in its natural environment,” says Beatrice Hahn, of the University of Alabama in Birmingham,

Adolescents from families where mealtimes and other activities are shared seem to have fewer mental health problems, reports a study in the Journal of Epidemiology and Community Health.

Researchers assessed the family habits and rituals of 82 first time users, aged between 14 and 23, of mental health services in one metropolitan area. Anxiety and depression were the main problems for which treatment was sought. Family practices in 177 young people within the same age band from various educa

Middle aged men should be heartened to know that frequent sex is not likely to increase their risk of stroke. It may actually reduce the risk of sudden death, suggests research in the Journal of Epidemiology and Community Health.

The Caerphilly study, which takes its name from a former mining town in South Wales, involves tracking the development of heart disease in almost 3000 men. All were aged between 45 and 59 when recruited to the study between 1979 and 1983.

Just under 1000 m

Researchers finally measure the subtle quantum effects of fourth fundamental force.

Far from falling smoothly, objects moving under gravity do so in lurching, quantum leaps, a French experiment has revealed 1 . The finding confirms that gravity, like the Universe’s three other fundamental forces, can have a quantum effect.

Particles, such as electrons confined to their orbital shells around the nucleus of an atom, are restricted by the rules of quantum mechan

A new type of Earth ecosystem could be found on other planets.

Scientists have found a community of microbes unlike anything else on Earth. Conditions in this ecosystem could mimic those on Earth when life began, and might exist elsewhere in today’s Solar System.

Home to the microbes is a hot spring 200 metres beneath the US state of Idaho. Their lives owe nothing to the Sun. They generate energy by combining hydrogen from rocks with carbon dioxide, releasing methane as a by

Cellular attack tactic keeps virus at bay.

A new AIDS vaccine could be one of the most promising yet. The drug’s effects in monkeys suggest that killing virus-laden cells may form a key part of future vaccination strategies.

Vaccinated monkeys survived a usually lethal infection with a monkey-human hybrid virus, SHIV. Their primed immune system kept virus levels below detection, Emilio Emini of Merck Research Laboratories in West Point, Pennsylvania, and his team now report