President Trump’s immigration crackdown ensnared Kseniia Petrova, a scientist who fled Russia after protesting its invasion of Ukraine. She fears arrest if she is deported there.

Two significant programs that invested in research on diabetes, dementia, obesity and kidney disease have ended since the start of the Trump administration.

© Haiyun Jiang for The New York Times

While some agree with Robert F. Kennedy Jr. that the agency needs reform, their ideas for fixing it are very different from his.