Published: Sunday 15 August 2004

how planets form: Elongated dust clouds, rather than fluffy blobs of dust, are the seeds of planet formation. This is the finding of experiments conducted by Jrgen Blum of the Technical University of Germany and Maya Krause of the Friedrich Schiller University, also based in Germany. The experiments were performed aboard an unmanned rocket that spent six minutes in microgravity in 1999. The researchers found that planets condense from dusty clouds when electrostatic forces hold sway over gravity. The dust particles seem to grow in long strings as opposed to clumps -- the conventional belief.

unpardonable offence: DuPont Corporation, the leading chemical manufacturer of the US, has failed to report the potential health risks caused by a key ingredient of Teflon. As per the US Environmental Protection Agency (EPA), the company violated the Toxic Substances Control Act from June 1981 to March 2001 by not reporting dangers associated with perfluorooctanoic acid or C-8. The chemical is crucial in the process of making the well-known coating used in a wide range of consumer products, including non-stick cookware and stain-resistant carpets.

Tests by 3M, the original manufacturer of C-8, have shown that high levels of exposure may cause liver damage and reproductive problems in rats. Tom Skinner, head of EPA's enforcement office, said the company could face penalties of US $25,000 per day for violations before January 30, 1997. They will rise to US $27,500 per day after that. This means a total fine in the range of US $300 million. The company has stated that the EPA allegations are baseless.

gender bender: One-third of male fish in British rivers have physical characteristics of females due to hormone pollution. This is the finding of a survey of 1,500 fish from 50 rivers. It was conducted by UK's environment agency. As per the agency, the problem could damage fish populations by reducing their ability to reproduce.

better way to copy DNA: Scientists have developed a new method for DNA amplification that could replace polymerase chain reaction (PCR) -- a technique invaluable for research at present, but which is confined to the laboratory. HDA (helicase-dependent amplification) has many advantages when compared to PCR. The latter requires 'thermocycling' to heat and cool samples of DNA for separating and synthesising the genetic material. HDA instead mimics nature's method of replicating DNA by using an enzyme. As a result, the entire HDA reaction can be performed at one temperature that is optimised for synthesis, eliminating the need for an power-hungry thermocycler. The cost of HDA is expected to be more modest than PCR, and most importantly the simplicity of HDA makes it suitable for the development of hand-held DNA diagnostic devices that could be used to detect pathogens in the field.

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