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A rash of anxiety in Britain about prion diseases apparently caused by infectious proteins suggests it is time for the government to change its line on the risks to people of bovine spongiform encephalitis.
Earlier speculations about the entropy of black holes has prompted an ingenious calculation suggesting that entropy may (in special circumstances) be the same inside and outside an arbitrary boundary.
This week's sampler includes a new kit for the rapid purification of polymerase chain reaction (PCR) products, a new matrix for isolating PCR-quality DNA and a kit for PCR amplification of the 5' ends of cDNAs.
