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A 1936 prediction read in the X-rays of a magnetar: the vacuum polarizes
The X-rays from magnetar 1E 1547.0−5408 are 65% polarized at 2 keV, reaching nearly 80% at certain phases — a level that surface models without refraction cannot explain. Vacuum birefringence, predicted by QED almost 90 years ago, offers the most natural reading. Strong evidence, not yet direct confirmation.
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The ovary always keeps the same share of its reserve in activation: 14%, from puberty to the end of reproductive life
By mapping more than 85,000 oocytes in whole mouse ovaries using light-sheet microscopy, a CRG team shows that the share of the reserve undergoing activation stays close to 14% while the stock itself collapses by more than an order of magnitude. Regulation appears proportional rather than absolute.
Severe COVID wakes dormant viruses — and one of them marks long COVID
Across 1,154 hospitalized patients, nearly one in two sees a dormant chronic virus reactivate during acute COVID — herpes, cytomegalovirus, Epstein-Barr, but also the inconspicuous anelloviruses. The latter are associated, during convalescence, with the form of long COVID marked by physical disability. Association, not causation: the authors say so in black and white.
A radial-nanochannel carbon makes it possible to heat a platinum-cobalt catalyst to 1000 °C without coarsening it
Ordering a platinum-cobalt alloy requires heat; but heat coarsens the nanoparticles and ruins their active surface. A team at Washington University in St. Louis reports breaking that trade-off by confining the particles inside carbon channels.