"If they can deliver what they are saying, and you don't even have to make a change in the vehicle, that is a positive check in the column, " says Ron Pernick, a partner at clean-technology research and publishing firm Clean Edge.

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Keepers have learned to use positive reinforcement, offering rewards to animals that present themselves for injections and check-ups.

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If the check is a low amount, however, the hassle may neutralize anything positive about receiving the refund.

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Every six months she will have a check-up to see if the cancer has returned, but she is positive that the worst is behind her now.

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This regular check on the order books of Scotland's private companies has previously been more positive than other data over the downturn.

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The Police and Crime Commissioner admitted his idea was "not the finished product" and he needed to check the legality of the proposal but he had had "a lot of very positive coverage so far".

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