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How the comic strip 'Baldo' blends humor with humanity

How the comic strip 'Baldo' blends humor with humanity

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Losing census fight, how Trump will seek citizenship data

Losing census fight, how Trump will seek citizenship data

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Sec. Wilkie on expanding health care for veterans

Sec. Wilkie on expanding health care for veterans

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Why some small marijuana growers struggle after legalization

Why some small marijuana growers struggle after legalization

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How Grammy-nominated singer Falu found her identity in music

How Grammy-nominated singer Falu found her identity in music

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Why it's so hard to get Republican women in Congress

Why it's so hard to get Republican women in Congress

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Why Tropical Storm Barry threatens more than just the coast

Why Tropical Storm Barry threatens more than just the coast

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Why legal marijuana industry now struggles with diversity

Why legal marijuana industry now struggles with diversity

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Tumultuous week in White House ends with Acosta resignation

Tumultuous week in White House ends with Acosta resignation

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Shields and Ponnuru on Democratic division, citizenship data

Shields and Ponnuru on Democratic division, citizenship data

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News Wrap: House committees might delay Mueller testimony

News Wrap: House committees might delay Mueller testimony

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Pelosi and Ocasio-Cortez expose Democrats' big divide

Pelosi and Ocasio-Cortez expose Democrats' big divide

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3:37
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PBS News Hour

Scientists race to learn how marijuana affects the brain

As national attitudes and laws around cannabis use have evolved, so have the commercially grown strains of the plant. Some marijuana varieties today contain levels of THC, the drug’s psychoactive compound, as high as 50 percent, compared to around 5 percent a generation ago. But as science correspondent Miles O'Brien reports, the effects of cannabis on the human brain are still relatively unknown.
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