Narrow-ridged finless porpoises were long assumed to be mostly solitary species with little allomaternal interaction. In a new study, researchers from Kindai University found four infant porpoises swimming with non-mother adults. The functions of these interactions are unclear. It is possible that they reduce swimming effort for infants and help young females learn to interact with infants before having their own offspring. These findings are valuable for wildlife conservation and rehabilitation of abandoned infant porpoises.

Birth order, a non-genetic factor, may influence early neurodevelopment. A nationwide Japanese birth cohort study based on sibling pairs suggests that differences in neurodevelopment emerge during the first year of life. Second-born infants scored slightly lower than firstborns across several domains and had lower levels of parental engagement. The study suggests that differences in caregiver-reported parental engagement may partly account for these small but consistent early developmental gaps, though their long-term clinical significance remains unclear.

Tokyo, Japan – Scientists from Tokyo Metropolitan University have discovered that a hydrogen-absorbing material shrinks in one direction upon heating, so-called negative thermal expansion (NTE). They found that this NTE is driven by a phase transition in the alignment of magnetic moments, an entirely different mechanism from its hydrogen-free counterpart. Since hydrogenation can be tuned, their findings promise customized high-precision ingredients in materials which don’t change in volume on heating, for next-generation precision nanotechnology.

Demon Slayer, a well-known anime depicting a bamboo muzzle worn by a character, has been investigated from various perspectives. However, its scientific perspective particularly the depiction of bamboo muzzle remains unexplored. To fill this gap, a new study compared the lengths of bamboo segments shown in anime illustrations with measurements from real plants and mathematical models. The findings reveal major differences in the structure of anime bamboo and actual bamboo, enhancing public understanding about bamboo.

Researchers from Japan have uncovered direct evidence showing how ketamine exerts its rapid antidepressant effects in patients with treatment-resistant depression, using a novel brain imaging technique to visualize molecular changes in the living human brain. Using positron emission tomography imaging with the newly developed tracer [¹¹C]K-2, the study shows that ketamine’s antidepressant effects are mediated by region-specific changes in AMPA receptor density that correlate with symptom improvement, bridging findings from animal models to human patients.

To meet global food demands, aquaculture — the farming of aquatic creatures like fish or shrimp — is on the rise.

However, productivity in the industry is still limited due to early-life bottlenecks, with high mortality rates caused by disease outbreaks, environmental changes and stress.

Now, a team from the Okinawa Institute of Science and Technology (OIST) has developed a scalable aquaculture platform designed to address these challenges. The system automates the sensitive phases of aquaculture — hatching and transfers — which can minimize pathogen exposure, animal stress and labor input.

Researchers at the Cancer Research Institute and the Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, have uncovered a critical mechanism that enables gastric cancer to spread to distant organs. Their study shows that cancer cells stimulate Wnt signaling in surrounding stromal fibroblasts to produce hyaluronan, creating a supportive microenvironment that promotes metastasis.

These findings provide new insight into how metastatic tumors establish themselves and suggest promising strategies to prevent gastric cancer progression.

An Osaka Metropolitan University-led research team discovered a novel bacterial species after analyzing cells isolated from the stomach of a Helicobacter pylori-positive Japanese female patient.

Japanese red elder plants safeguard their own survival when they drop fruits infested by Heterhelus beetle larvae, as well as the survival of these larvae. The Kobe University study changes the narrative on how a plant and its pollinator can keep benefits balanced.

To better understand how microplastics move through the body, researchers at Tokyo University of Science, Japan, have developed fluorescent nano-sized microplastics that can be tracked in real time using deep-tissue imaging. By loading common plastics with a fluorescent dye, they observed how particles of varying shapes and sizes travel through the digestive tract before being excreted in mice. These realistic microplastic models provide a powerful platform for studying their behavior and assessing potential health risks.