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Stray WiFi Signals Could Let Spies See Inside Closed Rooms

Slashdot - Sat, 04/29/2017 - 12:00
sciencehabit quotes a report from Science Magazine: Your wireless router may be giving you away in a manner you never dreamed of. For the first time, physicists have used radio waves from a Wi-Fi transmitter to encode a 3D image of a real object in a hologram similar to the image of Princess Leia projected by R2D2 in the movie Star Wars. In principle, the technique could enable outsiders to "see" the inside of a room using only the Wi-Fi signals leaking out of it, although some researchers say such spying may be easier said than done. Their experiment relies on none of the billions of digital bits of information encoded in Wi-Fi signals, just the fact that the signals are clean, "coherent" waves. However, instead of recording the key interference pattern on a photographic plate, the researchers record it with a Wi-Fi receiver and reconstruct the object in a computer. They placed a Wi-Fi transmitter in a room, 0.9 meters behind the cross. Then they placed a standard Wi-Fi receiver 1.4 meters in front of the cross and moved it slowly back and forth to map out a "virtual screen" that substituted for the photographic plate. Also, instead of having a separate reference beam coming straight to the screen, they placed a second, stationary receiver a few meters away, where it had a direct view of the emitter. For each point on the virtual screen, the researchers compared the signals arriving simultaneously at both receivers, and made a hologram by mapping the delays caused by the aluminum cross. The virtual hologram isn't exactly like a traditional one, as researchers can't recover the image of the object by shining more radio waves on it. Instead, the scientists used the computer to run the radio waves backward in time from the screen to the distance where wave fronts hit the object. The cross then popped out.

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EPA Website Removes Climate Science Site From Public View After Two Decades

Slashdot - Sat, 04/29/2017 - 09:20
Last week there were reports that the EPA climate change website was set to be taken down, though later the EPA denied that. On Friday evening, however, the Environmental Protection Agency announced its website would be "undergoing changes" to better represent the new direction the agency is taking, triggering the removal of several agency websites containing detailed climate data and scientific information (paywalled; alternative source). From a report on The Washington Post: One of the websites that appeared to be gone had been cited to challenge statements made by the EPA's new administrator, Scott Pruitt. Another provided detailed information on the previous administration's Clean Power Plan, including fact sheets about greenhouse gas emissions on the state and local levels and how different demographic groups were affected by such emissions. The changes came less than 24 hours before thousands of protesters were set to march in Washington and around the country in support of political action to push back against the Trump administration's rollbacks of former president Barack Obama's climate policies.

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Surgeon Plans To 'Reawaken' Cryogenically Frozen Brains, Transplant Them Into Someone Else's Skull

Slashdot - Sat, 04/29/2017 - 09:00
Sergio Canavero, the Italian surgeon who plans to perform the world's first human head transplant within the next year, says he is preparing to reawaken cryogenically frozen brains and transplant them into someone else's skull. "In an interview with a German-language magazine, Canavero says he will attempt to bring the first brains frozen in liquid nitrogen at an Arizona-based cryogenics bank back to life 'not in 100 years,' but three years at the latest," reports National Post. From the report: Transplanting a brain only -- and not an entire head -- gets around formidable rejection issues, Canavero said, since there will be no need to reconnect and stitch up severed vessels, nerves, tendons and muscles as there is when a new head is fused onto a brain-dead donor body. Canavero allows that one "problematic" issue with brain transplants, however, would be that "no aspect of your original external body remains the same." "Your head is no longer there, your brain is transplanted into an entirely different skull," he told OOOM magazine, published by the same company that handles the Italian brain surgeon's public relations. The flamboyant neuroscientist who some ethicists have decried as "nuts" rattled the transplant world when he first outlined his plans for a human head transplant two years ago in the journal, Surgical Neurology International. Bioethicist Arthur Caplan called Canavero's latest proposal to merge head transplants with "resurrecting" the frozen dead beyond ridiculous. "People have their own doubts about whether anything can be salvaged from these frozen heads or bodies because of the damage freezing does," said Caplan, head of ethics at NYU Langone Medical Centre in New York City. "Then saying that he has some technique for making this happen, that has never been demonstrated in frozen animals, is absurd."

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