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A group of brain cells called orexin neurons appears to help us keep working when reaching a reward becomes increasingly difficult。 Blocking their activity weakened motivation in rats, pointing to a possible new target for understanding why people sometimes struggle to sustain goal-directed behavior
Scientists have identified a molecular switch that may help explain why aging makes the brain more vulnerable to diseases such as ALS and Huntington’s。 In worms, the protein EPS8 builds up with age and triggers signaling that encourages toxic proteins to clump together, damaging neurons and shortening lifespan。 Reducing EPS8 activity prevented thes
DNA traces in the Shroud of Turin reveal a remarkable mixture of human lineages, microbes, plants, animals, and coral accumulated through centuries of handling and travel。 The findings do not prove its age or authenticity, but they expose a hidden biological history preserved in the famous cloth
The solar wind may be stripping away Mars’ atmosphere by creating giant rolling waves along its outer edge。 Data from MAVEN and Tianwen-1 show that these waves form plasma clouds that carry atmospheric particles into space。 The process is concentrated on one side of Mars and may have played a major role in drying out the once potentially habitable
Taiwan’s steep, remote mountains have sheltered extraordinary forests containing hundreds of giant Taiwania firs。 After years of difficult expeditions, LiDAR mapping, and citizen-science detective work, researchers discovered an 84。1-meter (276-foot) tree, the tallest known in East Asia
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
Homeland Security told immigrants that leaving the US would wipe out fines it claims they owe。 Now it wants private investigators to find them in their home countries and collect
A new chemical process can transform three of the most common plastics into high-purity hydrogen without sorting them first。 The technique operates at much lower temperatures than traditional gasification and captures most of the plastic’s carbon in solid or liquid forms instead of releasing it as carbon dioxide
NASA’s Swift Observatory observed a supermassive black hole ripping apart a star more than 30,000 light-years from the center of a distant galaxy。 The extraordinary flare briefly outshone its entire host galaxy in ultraviolet light and revealed a black hole about a million times the Sun’s mass
Although no one captured a direct image of the impact, scientists have detected signals confirming the rocket hit the lunar surface。 Orbiters could provide the first images of the crash site in the coming days
A mathematician working at Anthropic says he used the AI model Claude Fable 5 to uncover a remarkably simple counterexample to the Jacobian conjecture, a famous problem that has resisted mathematicians for more than a century。 The result shows that the conjecture is false in three dimensions and above, although the original two-dimensional version
Stanford researchers discovered immune cells in flatworms that explode within minutes, killing nearby bacteria and foreign cells before vanishing completely。 Their unusually fast and localized attack could offer clues for developing targeted treatments against infections and cancer