Kyoto, Japan -- Recently, while analyzing strong-motion data close to fault lines, a group of researchers at Kyoto University noticed something unexpected: a negative phase in the waveforms, a pattern that did not conform to the existing interpretations of rupture dynamics. Its regular appearance in the records near rupture end points suggested that the team might be seeing something new.

"This study originated from a broader effort to better understand near-fault seismic recordings and interpret them in terms of the earthquake source process," says first author Jesse Kearse. The researchers believed the repeated negative phase may represent an essential and previously overlooked component of the earthquake process, and were determined to figure out what was behind the mysterious regular dips.

The team's method combined observed ground motion with model predictions. They first analyzed near-field strong-motion acceleration records that had been carefully corrected for instrument noise. They then used satellite-based data to validate their ground-based measurements, and for the last step, simulated earthquake propagation and the abrupt arrest of rupture with numerical dynamic rupture models.

A new type of chatbot could reliably help people decide what to do about their symptoms — and do so based on guidance that is both medically sound and easy to understand. Designed to improve self-triage, the chatbot could help reduce unnecessary hospital visits and ensure that those who need care seek it sooner.

As space agencies and private companies look toward sustained human presence on the moon, a fundamental challenge centers on how to build strong, durable infrastructure without hauling every material from Earth. New research from Rice University points to an unexpected solution — transforming one of the moon’s most stubborn obstacles, its abrasive dust, into a valuable building resource.