Bacteriorhodopsin has the habit of changing from blue to pale yellow in an electric field, which might be useful in colour displays.

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Thousands of them waved yellow towels, making Ford field feel more like Heinz field, their usual digs in Pittsburgh.

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The hosts - who took to the field in fluorescent yellow with Leicester in baby blue - fielded a multi-national line-up which included former England and Wasps centre Fraser Waters and England Sevens and former Sale winger Andy Vilk.

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Then after just eight minutes South African Schalk Brits, forgetting any club loyalty, sent a punch towards his Saracens teammate and Lions flyhalf Owen Farrell, earning the Barbarians' hooker a yellow card and 10 minutes off the field.

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On the field that behavior now draws a yellow flag.

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It is tempting to see a recession as a yellow caution flag that slows all cars in the field.

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South Florida, wearing bright green-and-yellow uniforms, went 16 for 66 from the field and 5 for 26 (19 percent) from 3-point range.

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Sally Field in classic red Valentino, Jane Fonda in bright yellow Versace and Emmanuelle Riva in a teal gown that recalled society grande dames all looked regal in their fashion choices.

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