Tokyo, Japan – Researchers from Tokyo Metropolitan University have developed a suite of algorithms to automate the counting of sister chromatid exchanges (SCE) in chromosomes under the microscope. Conventional analysis requires trained personnel and time, with variability between different people. The team’s machine-learning-based algorithm boasts an accuracy of 84% and gives a more objective measurement. This could be a game changer for diagnosing disorders tied to abnormal numbers of SCEs, like Bloom syndrome.

445 million years ago, life on our planet was forever changed. During a geological blink of an eye, glaciers formed over the supercontinent Gondwana, drying out many of the vast, shallow seas like a sponge and giving us an ‘icehouse climate’ that, together with radically changed ocean chemistry, ultimately caused the extinction of about 85% of all marine species – the majority of life on Earth.

In a new Science Advances study, researchers from the Okinawa Institute of Science and Technology (OIST) have now proved that from this biological havoc, known as the Late Ordovician Mass Extinction (LOME), came an unprecedented richness of vertebrate life. During the upheaval, one group came to dominate all others, putting life on the path to what we know it as today: jawed vertebrates.

A new study published in Conservation Biology examines the behavior and distributions of queen conch (Aliger gigas) to guide conservation management for the threatened sea snail. The research, which tracked adult snail movements, suggests that establishing a 330-meter spatial buffer – about the height of the Eiffel Tower by comparison – around breeding areas could help protect conch populations and serve as a practical tool for local management.

The flagellar tails of bacteria rotate clockwise or counterclockwise because of active mechanical forces that pressure the individual ‘teeth’ of a gear to cooperate. This revises a decades-old model of how bacteria tails switch their rotational direction. The study, led by scientists at the Flatiron Institute, appears in Nature Physics.

We've all been there…

You know you need to make that complaint phone call, but you cannot bring yourself to dial. Or there is a project your demanding boss assigned, and even though you know you should start, you just…can't. You’re stuck at the starting line, caught in that all-too-familiar sense of motivational paralysis.

Why is it so hard to just get started?

Now, scientists at Kyoto University's Institute for the Advanced Study of Human Biology (WPI-ASHBi) have discovered what's happening in the brain during these frustrating moments. The research team conducted research on macaque monkeys and identified a specific brain circuit that acts like a "motivation brake": a neural pathway connecting two brain regions (the ventral striatum and ventral pallidum) that kicks in when we are confronted with tasks that come with negative consequences. When the scientists temporarily disabled this circuit, the motivational brake released: tasks that were once avoided suddenly became approachable. This discovery may help explain why, for some people (such as those living with depression), starting even simple tasks can feel impossibly hard. By identifying the brain "switch" behind this motivational paralysis, researchers may be one step closer to developing new treatments that help people overcome this invisible barrier.

The research is led by Dr. Ken-ichi Amemori, Dr. Jungmin Oh, and Dr. Satoko Amemori, with Dr. Masahiko Takada (Professor, Center for Human Behavior Evolution Research; currently Professor Emeritus), Dr. Ken-ichi Inoue (Assistant Professor; currently Associate Professor at Nagoya City University), and Dr. Kei Kimura (Assistant Professor, Tohoku University). The findings of this study will be published online in Current Biology at 11:00 a.m. on January 9, 2026 (EST; January 10, 1:00 a.m. JST).