China’s research and experimental development (R&D) spending totaled 3.92882 trillion yuan in 2025, up 296.13 billion yuan (8.2% YoY). R&D intensity (R&D/GDP) rose to 2.80%, an increase of 0.11 percentage point. R&D expenditure per full‑time‑equivalent R&D worker was 487,000 yuan, up 7,000 yuan year‑on‑year.

U.S. President Trump said he would not use nuclear weapons against Iran.

The 28th General Conference on Weights and Measures on the 15th in Versailles, France adopted a resolution to implement "continuous Coordinated Universal Time" from 20 May 2027. The change means UTC will no longer be adjusted by adding or subtracting leap seconds and could remain continuous for several centuries. UTC is currently the only time scale recommended as an international reference; it runs at the same rate as International Atomic Time while historically using leap seconds to stay close to Earth-rotation-based Universal Time. Since 1972, UTC has added or removed one second when the monitored difference reached 0.9s. Under the resolution the maximum permitted difference going forward is set at 3,600 seconds (one hour).