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The failure of the US Congress to override the administration's veto of a bill to allow research with fetal tissue is a bad business, both for research and the civility of the coming election campaign.
The science museum in Florence has two telescopes and a single lens attributed to Galileo. Tests conducted with modern interferometric equipment show that Galileo was able to obtain nearly perfect optical quality.
The idea that nucleotide bases in strands of DNA may be correlated over several thousands of base-positions has been established, but has not yet been explained.
Scanning tunnelling microscopy and atomic force microscopy, one scanning the tunnelling current and the other the repulsive atomic force between sample and probe, can give high-quality surface topographies of proteins, which have been difficult to obtain by more conventional methods such as transmission electron microscopy.
New products featured this week include a gel designed specifically for the detection of point mutations and a nonradioactive assay for detecting HIV DMA.