This study explored the inhibitory effect of the high-power helium-neon ( He-Ne) laser on the growth of scars post trauma. Shu, Bin Ni, Guo-Xin Zhang, Lian-Yang Li, Xiang-Ping Jiang, Wan-Ling Zhang, Li-Qun High-power helium-neon laser irradiation inhibits the growth of traumatic scars in vitro and in vivo. High concentrations of 3 He and 21 Ne (extrap) are found in the glasses near 17°S, which is consistent with higher noble gas concentrations in the anomalous mantle.
The relationship between helium and neon isotopes and along-axis geophysical characteristics (and by inference melt distribution) is probably related to the extreme incompatibility of helium and neon. A conceptual model that fits the observations includes melting of an entrained heterogeneity beneath the EPR at 17 °S. Unradiogenic helium and neon values correlate with low mantle Bouguer anomalies, and maxima in the axial cross-sectional area, all of which are attributed to higher melt production near 17°S. The minimum in 4 He/ 3 He is observed from 16° to 18°S (a distance of ˜220 km), whereas the elevated Sr and Pb values, and lower 143Nd/ 144Nd, are observed between 16° and 20.7°S (a distance of ˜500 km) neon isotope anomalies are observed on an intermediate length scale along-axis. The minima in 4 He/ 3 He and 21 Ne/ 22 Ne correspond to extremes in Sr, Nd and Pb isotope ratios, but the length scale of the helium and neon anomalies are shorter along-axis than the peaks for the other isotopic ratios. The EPR at 17°S is unusual in displaying such isotopic anomalies in the absence of any known hotspot. The lowest corrected 21 Ne/ 22 Ne ratios are found near 16.75°S, and are consistent with the helium isotopes in suggesting a less degassed mantle source. Atmospheric contamination corrections on neon isotopes are made using step heating and extrapolated 21 Ne/ 22 Ne ratios (to a solar 20 Ne/ 22 Ne value of 13.8). The 3 He/ 4 He ratios vary from 8.0 to 11.0 times the atmospheric value (Ra), with the least radiogenic values in samples from near 16.75°S. We report new helium and neon isotopic compositions in dredged basalt glasses from the superfast spreading East Pacific Rise (EPR) between 13° and 23°S.
Moreira, Manuel Curtice, Joshua Lott, Dempsey E. Correlated helium, neon, and melt production on the super-fast spreading East Pacific Rise near 17°S
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