A researcher, professor and federal policy adviser, he guided students who went on to do groundbreaking work in connecting the world online.

San Ramon, Calif., has been rattled by dozens of small earthquakes in recent months. Even in a region used to regular shaking, it’s been a lot.

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A professor at the University of California, Santa Cruz, he was a key contributor to a landmark paper that laid out how the universe came to look like it does today.

Companies like Kairos Power are building new types of reactors with the encouragement of the Trump administration, but their success is far from assured.

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Brenna Henn had a long-term grant to study the genetic diversity of Africans and people of African descent. Then her N.I.H. funding was cut.

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