Researchers from Okayama University of Science and collaborating institutions have experimentally demonstrated the mathematical relationship between the number of collisions and the value of pi (π). By suspending the objects to minimize friction, the team successfully observed 31 collisions at a 1:100 mass ratio—corresponding to 3.1, the first decimal place of π—confirming that pi can be derived in real-world experiments.

Researchers at Nagoya University in Japan have developed a lipid nanoparticle that delivers mRNA to cells five times more effectively. By attaching a sulfur-containing ring structure—a cyclic disulfide—to lipid molecules, they found that significantly more mRNA can escape from cell components that normally destroy genetic material. When tested as a cancer vaccine in mice, the new delivery system stopped tumor growth. The study, published in the journal RSC Medicinal Chemistry, demonstrates the first successful use of cyclic disulfide-containing lipids to improve mRNA delivery in animals and suppress tumor growth.

A new soft actuator moves and stiffens like biological muscle. The muscles, or actuators, are constructed from low-cost, 3D-printed rubbers. Engineers integrated three actuators as ‘muscles’ into a human-sized robotic leg with 3D-printed rigid ‘bones’ and elastic ‘tendons’.

Daytime radiative cooling is an eco-friendly and passive cooling technology that operates without external energy input. Materials designed for this purpose are engineered to possess high reflectivity in the solar spectrum and high emissivity within the atmospheric transmission window. Unlike broadband-emissive daytime radiative cooling materials, spectrally selective daytime radiative cooling (SSDRC) materials exhibit predominant mid-infrared emission in the atmospheric transmission window. This selective mid-infrared emission suppresses thermal radiation absorption beyond the atmospheric transmission window range, thereby improving the net cooling power of daytime radiative cooling. This review elucidates the fundamental characteristics of SSDRC materials, including their molecular structures, micro- and nanostructures, optical properties, and thermodynamic principles. It also provides a comprehensive overview of the design and fabrication of SSDRC materials in three typical forms, i.e., fibrous materials, membranes, and particle coatings, highlighting their respective cooling mechanisms and performance. Furthermore, the practical applications of SSDRC in personal thermal management, outdoor building cooling, and energy harvesting are summarized. Finally, the challenges and prospects are discussed to guide researchers in advancing SSDRC materials.