"Some of the good software can detect it in the same day, " Thakur said.

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Mayersohn declined to discuss specific sales figures, but he did say that the margins on self-published books are very good (do I detect shades of Amazon here?), even better than those of the print-on-demand traditional books.

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Since the spatial resolution of SPECT is roughly equivalent to the thickness of the heart chamber wall, it can only detect those infarcts that have traversed a good portion of the chamber wall.

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He talks about the NHS being a series of "microclimates" where good practice can exist alongside bad, making it harder to detect.

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"If people are anxious, it's harder to detect if they're anxious because they're up to no good or anxious because of all the attention you are paying to them, " New York University professor Harvey Molotch said.

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The good news is that there is also a CT scan available to detect fatty deposits that constitute soft plaque, called a Coronary CT Angiography (CTA).

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That is good enough to see shifts caused if a star's companion is another star, but it cannot detect the tiny wobbles caused by orbiting planets.

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In fact the Rics survey has a good track record of having its finger on the pulse of the market and is often the first to detect significant changes.

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