I can't stick this picture down. I need better glue.

When two beams reconverge with the assistance of prisms, the phase difference between the two beams provides relieflike, high-contrast images of the specimen.

Mostly, the microbiome is beneficial. It helps with digestion and enables people to extract a lot more calories from their food than would otherwise be possible. Research over the past few years, however, has implicated it in diseases from atherosclerosis to asthma to autism.

This visit, and its cause, was truly historic: until this point, our nation had never had diplomatic relations with the People's Republic of China (P.R.C.). Since the P.R.C's founding on October 1, 1949, the United States had maintained diplomatic ties exclusively with the political remnant of Nationalist China's forces that had been driven from the mainland to the island of Taiwan. This relationship had become deeply embedded in the commercial, media, political, and military establishments of our country. During this time, the P.R.C. was almost invariably referred to in political debates as Red China and Communist, which had a negative connotation similar to the one terrorist has today. To me, Deng Xiaoping's welcome in Washington was an early indication of approval for the decision I had made to shift official diplomatic relations to mainland China.