Most of us have days at work when we walk around with a spring in our step and perform our tasks with gusto — and other days when our feet drag and we just can’t seem to get motivated. A new study encourages employees to look more closely at the people around them as one reason for that disparity. A team of researchers that included Gretchen Spreitzer, a management professor at the University of Michigan Ross School of Business, found that some employees are “de-energizers” who spread their dispiriting attitude to others. In nonacademic parlance, these people are known ...