Measurements of helium isotopes in particles separated from polar ice demonstrate that extraterrestrial ³He dominates the ³He flux at the GISP2 (Greenland) and Vostok (Antarctica) ice core sites. Replicate measurements of late Holocene ice samples yield ³He fluxes of 0.62±0.27×10⁻¹² cm³ STP cm⁻² ka⁻¹ (GISP2) and 0.77 ± 0.25 ×...
Dietary nitrate (NO3-), consumed primarily from leafy green and root vegetables, lowers blood pressure, improves vascular function and aerobic exercise performance. This performance-enhancing effect of nitrate supplementation is largely attributed to the increased bioavailability of the signaling molecule, nitric oxide (NO). Nitric oxide is a ubiquitous free radical signaling molecule...