Ionospheric perturbation during the South American total solar eclipse on 14th December 2020 revealed with the Chilean GPS eyeball.

The influence of the South American total solar eclipse of 14th December 2020 on the ionosphere is studied by using the continuous Chilean Global Positioning System (GPS) sites across the totality path. The totality path with eclipse magnitude 1.012 passed through the Villarrica (Lon. 72.2308°W and Lat. 39.2820°S) in south Chile during 14:41:02.0 UTC to 17:30:58.1 UTC and maximum occurred ~ 16:03:49.5 UTC around the local noon. The vertical total electron content (VTEC) derived by GPS sites across the totality path for two PRN's 29 and 31 show almost 20-40% of reduction with reference to ambient values. The percentage reduction was maximum close to totality site and decreases smoothly on both sides of totality sites. Interestingly, the atmospheric gravity waves (AGWs) with a period ~ 30-60 min obtained using wavelet analysis of VTEC timeseries show the presence of strong AGWs at the GPS sites located north of the totality line. But the AGWs do not show any significant effect on the VTEC values to these sites. Our analysis suggests, possibly an interplay between variability in the background plasma density and eclipse-generated AGWs induced plasma density perturbation could explain the observations.

In Vitro Assessment of Antileishmanial Activity of Natamycin and Nystatin

ABSTRACT The present study was aimed to evaluate the in vitro antileishmanial activity of four different concentrations of natamycin and nystatin by using MTT 3-(4.5-dimethylthiazol-2-yl)-2.5-diphenyl tetrazolium bromide reduction assay. In vitro antileishmanial activity revealed that the IC50 of natamycin (80.49 μg/ml) and nystatin (105.7 μg/ml) was less than that of sodium stibogluconate (127.9 μg/ml), and more than amphotericin B (18.91 μg/ml).