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Today's Summary

In extreme cold, says the World Resources Institute, one of the biggest challenges is getting fuel to power plants for electricity generation and to homes for heating. Thermo Fisher Scientific plans to close a manufacturing facility in Franklin at the end of the year but will not lay off as many employees as the Waltham-based scientific tools maker said it would just a week ago. A concept called the “p factor” attempts to explain why psychiatric disorders cannot be clearly separated.