This second kind of analysis is done by lining up lots of known binding sites for a particular protein, comparing them position by position, and so finding out which letter is most likely to occur at which position, and how probable it is that a different letter may sometimes crop up instead.

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So unless someone else delivers a letter or a weapon in a different way, it's over.

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For example, there are different ways of sounding the letter combination "int".

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SNPs are single-letter mutations within the DNA that determine how one person is different from another.

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That information revealed the two February tests by Halliburton of a slightly different cement slurry mix that showed it was unstable, the letter said.

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In the letter, Mr Rogers said the decision had been made following a discussion with different groups in the town.

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No matter how different the gameplay or setting, this format is always followed to the letter with almost no room for variance.

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In 2001 Grove and a doctor friend at Stanford University sent a letter to NIH director Elias Zerhouni with advice on how to organize NIH research grants around different diseases, including Parkinson's.

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In response to one letter from Ickes expressing concern over DNC funds, Clinton suggested a direct mail campaign with a different message.

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The other letter, sent to Senate Majority Leader Tom Daschle in Washington, "contains a somewhat different message than the others, " the officials said.

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"With so many stoves and fires and lots of different types of fuel around, there is a clear fire hazard, " the letter said.

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Again, many of the things that they talked about in their letter that they sent were, how do you have tax cuts for economic growth -- 25 different tax cuts were contained in the Recovery Act.

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For these and other reasons, which will be analysed at a different time and forum, we do not accept the "facts" as they appear in your letter of 25 July 2008.

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