Many big traders were happy to deal with Enron this week, although at shorter maturities and with less complex structures than in the past.

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Once a gamer downloads an easy-to-install plug-in, he or she can start competing with other players, rotating complex three dimensional molecular structures with a click of the mouse.

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They are adept at dealing with complex business and investment entity structures used by wealthy people.

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It opened in 1901 in a single small building and now is a complex of structures with 28 acres of floor space.

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That made it a shock when ministers unveiled a huge restructuring after the election, defended with complex arguments about patient choice and bureaucratic structures.

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But what does entrepreneurial marketing look like in big, complex organizations with silos, hierarchies and rigid structures built-in for decades?

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"There are some areas that relied on sophisticated and complex structures, where transactions were carried out with the primary objective of accessing the tax benefits, " Mr Jenkins is expected to say on Tuesday.

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They also quoted a letter from FSA chief Lord Turner saying the bank had left an impression with the regulator that "Barclays has a tendency continually to seek advantage from complex structures or favourable regulatory interpretations".

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