https://www.missionursa.org/research/heart-rate-variability%3A-a-signal-of-distress 2026-06-04 https://www.missionursa.org/research/the-watch-knew-first 2026-06-04 https://www.missionursa.org/research/wearables-provide-life-saving-data%3A-when-the-signals-are-accurately-interpreted 2026-06-04