on Monday said it expected fourth-quarter sales to rise in the “low-single-digit percent range,” despite what executives said was a “challenging environment” for the maker of diagnostic and life-sciences equipment. That forecast was more upbeat than FactSet’s expectations for a 5% fourth-quarter sales decline to $7.71 billion. Shares rose 2% after hours. Chief Executive Rainer Blair said the company’s core business saw “high-single-digit” revenue growth, while the molecular diagnostic business in Cepheid, which Danaher acquired in 2016, had “better than expected growth,” with more than $1 billion in respiratory testing revenue. The company made the remarks ahead of a presentation at the J.P. Morgan Healthcare Conference, set for Tuesday.