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Signals traveling from the gut to the brain may help turn meals into lasting memories。 Rats showed stronger memory activity after consuming nutritious foods, but not after drinking sweet liquids with little or no nutritional value。 Blocking the vagus nerve erased this effect and made it harder for the animals to remember where food had been located
Popular AI-powered food apps may make calorie counting easier, but they may also leave out a surprisingly large part of the meal。 Four apps underestimated calories and fat by about one-third when tested against carefully prepared meals。 High-fat ketogenic dishes appeared to cause the most trouble, while carbohydrates were measured more consistently
Cosmic expansion allows distant galaxies to move away faster than light, while still letting us see ancient light they emitted when they were much closer。 Eventually, accelerating expansion will push nearly every galaxy beyond our Local Group out of sight, making the Universe appear almost empty
Scientists have successfully generated electricity with a hydrogen turbine that produces its own pressure through detonation waves instead of relying on a mechanical compressor。 The breakthrough could unlock dramatically more efficient power systems for clean energy and future aviation
Engineers have transformed a notoriously brittle cobalt-aluminum compound into a material that is both extremely strong and capable of bending without breaking。 Their nanoscale design produced a yield strength about six to 10 times greater than high-strength structural steel while sustaining substantial deformation at room temperature。 The approach
Rice University chemists have found a new way to make neodymium, a rare-earth metal, interact with oxygen。 Using a specially designed molecular structure described as a “basket,” the team positioned the atoms so they could form a bond once thought unlikely。 The breakthrough produced highly reactive compounds that could eventually give chemists alte
A surprisingly simple change could make sodium-ion batteries far more powerful while opening the door to turning seawater into drinking water。 Researchers at the University of Surrey found that sodium vanadium oxide performs much better when its naturally occurring water is left inside instead of being removed during manufacturing
Mathematicians have shown that no electoral system can perfectly balance local representation, proportional national results, and a fixed-size parliament once enough parties compete。 A newly proposed voting method could soften these unavoidable trade-offs and produce outcomes that are much closer to fair
Ultrafast X-rays revealed how a molecule converts absorbed light into motion in just trillionths of a second。 Individual atoms recorded different stages of the process, opening a powerful new window into light-driven chemistry
Scientists have created an “electron lighthouse” that uses laser light to launch and steer electrons through a semiconductor without an applied electrical field。 The quantum effect could eventually improve optical sensors, communications, imaging, and information storage
Scientists have uncovered new evidence that Venus may still be tearing itself apart from within。 Advanced 3D simulations indicate that some of the planet's giant rift valleys formed relatively recently and could still be expanding。 The results suggest Venus has a far more active interior than researchers once believed, challenging the long-held vie
Photons traveling through a cloud of atoms can emerge so early that they appear to have spent a negative amount of time inside。 Researchers tested whether this was merely a misleading feature of the light pulse by making extremely weak measurements of the atoms。 Surprisingly, the atoms confirmed the same negative dwell time
NASA’s Psyche spacecraft aced its Mars flyby, using the planet’s gravity to speed toward its 2029 encounter with a metal-rich asteroid。 The spacecraft tested its cameras, magnetometer, and particle-detecting instruments, capturing unusual views of Mars and measuring its magnetic environment。 It also detected neutrons from the planet and spotted the