The United States is in the middle of what could be the worst measles outbreak in more than 20 years. California has had some small outbreaks but has largely been spared, in part because the state tightened its vaccination laws three years ago – after learning the hard way just how vulnerable communities become when parents stop immunizing their children.

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The Chronicle archive has photos dating back to the 19th Century. Critic Peter Hartlaub and librarian Bill Van Niekerken share secrets from the archive, including their favorite 1906 earthquake finds.

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For decades, records of police officers' misconduct were hidden from view. But a new law, SB1421, has thrust into public view numerous incidents of dishonesty, sexual misconduct and use of force.

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Joshua Kosman interviews Elliot Franks, who gave up a career as a mezzo-soprano for a new life and a new baritone voice after going through gender reassignment surgery. 

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For trans vocalists, the familiar categories that have long defined operatic and choral music don’t always apply. San Francisco Chronicle editor-in-chief Audrey Cooper talks with classical music critic Joshua Kosman about the artistic and physical realities of singing while trans.

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Uber is set to thunder onto Wall Street with a stock market debut valuing it at $100 million. Its massive initial public offering will have ramifications for San Francisco, the Bay Area and beyond.

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Over a brief seven-day span, California gun owners were allowed to buy high capacity magazines for the first time in almost 20 years following a judge's ruling. They went on a shopping spree.

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Commuters arriving by BART in downtown San Francisco Monday were met by teams of police officers, fare inspectors and managers in neon green vests. It was the beginning of an enforcement blitz meant to discourage fare evaders and reassure riders that lawlessness is not accepted aboard BART.

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From the archive: Chronicle reporters Jill Tucker and Joaquin Palomino offer an inside look at the months they spent documenting the steep drop in youth crime. But they found the good news meant empty cells and also eye-popping costs.

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Giants fan Bryan Stow, who suffered severe brain damage in a March 2011 assault at Dodger Stadium, is starting to feel ‘whole’ again through sharing his anti-bullying message with kids.

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