Cavernous Weathering in the Taylor Dry Valley, Victoria Land, Antarctica
TAYLOR VALLEY (77° 33′ S., 163° 25′ E.) is part of a deglaciated valley complex called the McMurdo Oasis, which is located about 80 km to the west of Ross Island across McMurdo Sound. Since the IGY many New Zealand and American geological parties have worked in this area1–3, which is easily accessible by helicopter from Scott Base and McMurdo Station at the southern end of Ross Island. Now that the topographical and geological reconnaissance stage has been completed and adequate maps cover the 2,500 km2 of the McMurdo Oasis, more attention is being devoted to the study of various anomalies and problems.
Effects of ferrocyanide ions on NaCl crystallization in porous stone
Abstract The effects of [Fe(CN) 6 ] 4− ions on the crystallization of NaCl in aqueous solution has been studied, particularly in the situation where the saline fluid percolates through and evaporates from a saturated porous body (i.e., an ornamental porous limestone). In concentrations ranging from 2.48×10 −4 up to 2.85 10 −3  M the additive was able to increase the solution critical supersaturation (up to 8%) resulting in a significant crystallization inhibition effect, which promoted efflorescence growth on the porous stone surface as opposed to subflorescence growth. The former induced no damage to the stone support while the latter always resulted in crystallization pressure development inside the pores, causing granular disintegration—a process also known as “salt weathering”. Significant changes in NaCl crystal growth morphology (from {1 0 0} towards {1 1 0}, {1 1 1} and {2 1 0} forms) were observed in the presence of ferrocyanide ions, which also promoted the growth of dendrites with their main growth axis parallel to 〈1 1 1〉, and branched along 〈1 0 0〉, at the highest supersaturation. The possible inhibiting mechanism of ferrocyanide on NaCl crystallization and growth is discussed based on the evolution of NaCl growth morphologies, and some practical applications of ferrocyanides to prevent salt damage and enhance desalination in ornamental stones are outlined.
Thorium-induced Anatomical and Histopathological Changes in Liver of Swiss Mice
ObjectivePresent study is aimed to investigate the anatomical and histopathological changes in liver tissues of Swiss albino male mice, one month after intravenous administration of thorium (232Th; 4 and 40 mg/kg).MethodsSynchrotron X-ray micro-CT imaging, CD31 immuno-cytochemistry, hematoxylin & eosin staining and Periodic acid-Schiff staining were performed to study changes in liver anatomy, blood vessels/capillaries, histology and glycogen content of liver, respectively.ResultsSynchrotron X-ray micro-CT imaging of liver showed loss of blood vessels in mice treated with thorium (4 mg/kg), which was more prominent at higher dose of thorium (40 mg/kg). These thorium-induced changes in liver were correlated with the decrease in CD31 positive cells and loss of tissue architecture. A dose-dependent increase in glycogen content was also observed in the liver of thorium-treated mice.ConclusionOur results provide novel insight about the effects of thorium on liver, which may have significant implications in understanding the mechanism of thorium thorium-induced hepatotoxicity.