Tokyo, Japan – Researchers from Tokyo Metropolitan University have solved a long-standing mystery behind the drainage of liquid from foams. Standard physics models wildly overestimate the height of foams required for liquid to drain out the bottom. Through careful observation, the team found that the limits are set by the pressure required to rearrange bubbles, not simply push liquid through a static set of obstacles. Their approach highlights the importance of dynamics to understanding soft materials.

 Assistant Professor Daiki Tajiri and Professor Shozo Kawamura of the Machine Dynamics Laboratory, Technology Department of Mechanical Engineering, Toyohashi University have developed a simple method that identifies the rigidity deterioration of a building’s columns based on only the frequency response of force measured using an inertial shaker installed on the top floor of the building. This method enables the diagnosis of abnormalities in the entire building without requiring acceleration sensors and other equipment on multiple floors, as in the case of conventional methods; in fact, it requires only force sensors. The research results are published in the international academic journal Mechanical Systems and Signal Processing.

Researchers at Nagoya University in Japan have discovered that Cepheid variable stars in our neighboring galaxy, the Small Magellanic Cloud, are moving in opposing directions along two distinct axes. They found that stars closer to Earth move towards the northeast, while more distant stars move southwest. This newly discovered movement pattern exists alongside a northwest-southeast opposing movement that the scientists previously observed in massive stars.

Scientists from Kyushu University have identified the long-sought “orange gene” behind ginger fur in domestic cats—a deletion mutation in a gene on the X chromosome. This discovery explains why most orange cats are male while tortoiseshell and calico cats are female, and reveals a new genetic mechanism for orange coloring. The study solves a decades-old mystery in feline genetics, with their findings published in Current Biology on May 15, 2025.

A research team consisting of Kazumasa Uehara, Associate Professor in the Department of Computer Science and Engineering at Toyohashi University of Technology, and Yuya Fukuda, a pre-doctoral candidate in the same department, demonstrated that scalp electroencephalogram (EEG) power modulation of 4–8 Hz theta oscillation, known as frontal midline theta (FMT), observed in the medial frontal cortex just before initiating a movement is likely a key neural indicator explaining individual differences in the speed of motor skill acquisition. Analysis of scalp EEG data during a motor learning task integrating vision and motor action revealed that subjects who learned more quickly exhibited higher FMT power just before movement onset. These findings would contribute to the future development of personalized learning support and training methods based on EEG. Such methods could be applied in physical education fields such as rehabilitation and sports training, which require motor learning, as well as in enhancing musical instrument performance skills. The results of this research were published online in Experimental Brain Research on May 15, 2025.

Charge transfer, or the movement of electrons, can occur either within a molecule or between two molecules. Combining the two types of charge transfer is challenging. Now, scientists from Shibaura Institute of Technology, Japan, have developed a hybrid charge transfer crystal using a novel pyrazinacene molecule. This crystal is capable of reacting with naphthalene to produce a reversible color shift, from greenish-blue to red-violet. Such color-changing crystals can have various potential applications in materials science.