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The US Supreme Court has been hearing arguments about whether states that have legalized the medical use of marijuana are in breach of federal law. But medical agencies engaged in its clinical testing should not be deterred from their work.
The idea of therapeutic cloning, which offers the potential of growing replacement tissues perfectly matched to their recipients, is falling from favour. But there are alternatives, as Peter Aldhous found out.
Various reasons have been proposed for the falling numbers of amphibians in many parts of the world. Changing climate is likely to be a key factor — but with complicated links to the immediate causes of these population declines.
The idea of repairing damaged heart tissue with donated cells is an old one, but finding cells that can do the job has been frustrating. The solution may come from a select group of bone marrow cells.
Combinatorial approaches provide a way of swiftly analysing huge numbers of samples. They are now being used to test the structural properties of materials, such as hardness and elasticity.
Organisms often identify the source of a sound by comparing the noises that arrive at the two ears. Using some interesting tricks, a minute fly has mastered this feat as accurately as humans.
Ultrafast observations of fluid interfaces show that the way molecules interact at these junctions is both structurally and dynamically different from interactions in the bulk liquid.
Rises in the level of calcium ions inside cells are key biological signals. A long-sought protein involved in the 'store-operated' process by which calcium ions enter cells has now been identified.
Measurement of the total emissions of greenhouse gases implies specifying 'tradeoffs' of one against another, as in the Kyoto Protocol. In that process, economics has to be taken into account.
