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This week's award is for science that sheds light on a range of physical phenomena including liquid-metal surfaces and condensed matter. In chemistry news, nanotubes are feeling the heat of chilies and while analysts are musing on the lack of psychedelics in artists' tipple absinthe. Also, this week, X-ray studies are helping in the redesign of novel anticancer compounds, while a connection the great British seaside holiday, kelp and iodine as an oxidant is revealed. Finally, plastic lasers could open the door for a new range of spectroscopic and medical diagnostics instrumentation.

Oleg Shpyrko, a researcher at Argonne National Laboratory's Advanced Photon Source is set to receive the organization's 2008 Rosalind Franklin Young Investigator Award for his outstanding research. The award, named for the pioneering UK crystallographer, recognizes important scientific and technical accomplishments made in the field at an early age. Shpyrko has shone again and again in his work at the APS using surface and coherent X-ray scattering techniques to understand the structure and dynamics of liquid-metal surfaces and quantum states in condensed matter systems.

Ever wanted to know just how hot that spicy dish is going to be before sinking your teeth into it? Well, Richard Compton and his colleagues at Oxford University, England, have developed a novel technique to measure the concentration of the spicy hot compounds found in chili peppers, capsaicinoids, using carbon nanotubes. Writing in The Analyst, the team points out that their new chili sensor unambiguously determines the precise levels of capsaicinoids present, is quicker and cheaper than hired taste-testers and could be carried out inline during production. Capsaicinoids in a sample are adsorbed on to multi-walled carbon nanotube electrodes, with electrooxidation translating into the equivalent of the Scoville "heat" unit.

Absinthe, an alcoholic beverage usually of green hue, took on an almost mythological status as the artist's muse during the nineteenth and early twentieth century. Most art historians and the artists themselves often claimed its reputation as the "green fairy" that inspired a thousand works of art was due to the presence of hallucinogens, including thujone. However, recent analytical work by researchers in Germany and the USA on nineteenth century samples of absinthe shows only traces of thujone, way below any psychotropic level. The researchers conclude that rather than there being any such compound to endow the green fairy with its purported artistic properties it is merely the fact that absinthe is 70% alcohol (140 proof).

The X-ray crystal structure of the anticancer compound BRACO-19 reveals how it interacts with its molecular targets - the human quadruplexes of guanine-rich DNA found at the ends of chromosomes. The structure obtained by Stephen Neidle of the University of London and colleagues could help drug designers create more effective analogs with lower toxicity. The BRACO-19 family of acridine compounds was designed and created by Neidle's team, but early toxicity studies meant their commercial development with Antisoma was put on hold. New analogs are now being investigated and more based on the new work will presumably be taken up soon.

Seaweed could be to blame for the UK's traditional wet seaside holiday. Seaweed releases iodine into the atmosphere, which then seeds cloud formation. But, why seaweed needs such large amounts of iodine was not known until an international team figured out that iodide mops up reactive oxygen species and so protects kelp from damage when it is exposed to sunlight and in the temporary dryness of low tide. "When kelp experiences stress," explains Frithjof Küpper from the Scottish Association for Marine Science, "it very quickly releases large quantities of stored iodide. These ions detoxify ozone and other oxidants and produce molecular iodine." There are extensive kelp beds around rocky coastal areas of the UK, which could go part way to explaining the longer lasting cloud cover of coastal regions and the typically moody British coastal skyline.

A low-cost tunable visible light source for medical use could emerge from research being carried out at St Andrews University, in Scotland. The device is based on a nitride LED that is used to pump a semiconducting polymer laser, according to team leader Ifor Samuel, and could be used in spectroscopy, chemical sensing and point-of-care medical diagnostics. A device like this could be very inexpensive Samuel explains, because it circumvents the need for an expensive pump laser. "We have shown that it is possible to use a nitride LED to pump a polymer laser leading to a compact, easy-to-make and low-cost package," he says.