Li et al. 2017;3:e1602045

Inspired by a manta ray, scientists have built a small, squishy robotic fish that can swim and turn by remote control. Using the surrounding water as an electrode to capture and distribute electrical energy, the self-powered machine treads water twice as fast as similar robots and can function in a range of water temperatures. The biggest advance, though, is its energy efficiency — the robot can operate for three hours without recharging.

"[It] is an elegant demonstration of the emerging capabilities of soft robots," says Harvard's Michael Wehner, who last year built an octopus robot powered by hydrogen peroxide.

Why it matters: Robots will soon move out of warehouses and hospitals and into harsher, less predictable environments where they'll have to navigate small spaces and interact with humans (they may eventually even move through our bodies to diagnose disease in a next generation of endoscopies). To make it, they'll need to be compact, soft and flexible.

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36 mins ago - Health

Florida reports another daily record for coronavirus deaths

Nurse practitioner Barbara Corral and a research assistant conduct a COVID-19 vaccination study on August 7 in Hollywood, Florida. Photo: Joe Raedle/Getty Images

Florida's health department on Tuesday reported 276 new coronavirus deaths, surpassing the state's record from July 31.

The big picture: The state also recorded over 5,800 new cases — on the low side for a state that is one of the domestic epicenters for the virus.

Updated 1 hour ago - Politics & Policy

Coronavirus dashboard

Illustration: Annelise Capossela/Axios

  1. Global: Total confirmed cases as of 11:30 a.m. ET: 20,126,452 — Total deaths: 737,285 — Total recoveries: 12,380,410Map.
  2. U.S.: Total confirmed cases as of 11:30 a.m. ET: 5,098,452 — Total deaths: 163,533 — Total recoveries: 1,670,755 — Total tests: 62,513,174Map.
  3. States: State testing plans fall short of demand — National Governors Association's bipartisan leaders express concern over Trump's unemployment order.
  4. Axios-Ipsos poll: 1 in 2 has a personal connection to COVID-19.
  5. Business: Moderna reveals it may not hold patent rights for vaccine.
  6. World: New Zealand reports first local cases for 102 days — Why you should be skeptical of Russia's vaccine claims.

Exclusive: Facebook cracks down on political content disguised as local news

Illustration: Eniola Odetunde/Axios

Facebook is rolling out a new policy that will prevent U.S. news publishers with "direct, meaningful ties" to political groups from claiming the news exemption within its political ads authorization process, executives tell Axios.

Why it matters: Since the 2016 election, reporters and researchers have uncovered over 1,200 instances in which political groups use websites disguised as local news outlets to push their point of view to Americans.