Multiple sources of water preserved in impact glasses from Chang'e-5 lunar soil.

The existence of molecular H2O and evolution of solar wind-derived water on the lunar surface remain controversial. We report that large amounts of OH and molecular H2O related to solar wind and other multiple sources are preserved in impact glasses from Chang'e-5 (CE5) lunar soil based on reflectance infrared spectroscopy and nanoscale secondary ion mass spectrometry analyses. The estimated water content contributed by impact glasses to CE5 lunar soil was ~72 ppm, including molecular H2O of up to 15 to 25 ppm. Our studies revealed that impact glasses are the main carrier of molecular H2O in lunar soils. Moreover, water in CE5 impact glasses provides a record of complex formation processes and multiple water sources, including water derived from solar wind, deposited by water-bearing meteorites/micrometeorites, and inherited from lunar indigenous water. Our study provides a better understanding of the evolution of surficial water on airless bodies and identifies potential source and storage pathways for water in the terrestrial planets.

Pentraxin-3 Promotes LPS-Induced Pyroptosis in Human Periodontal Ligament Stem Cells.

The aim of this study was to explore the function of Pentraxin-3 (PTX3) in cell viability, pyroptosis, inflammation, osteogenic differentiation, and oxidative stress of lipopolysaccharide (LPS)-stimulated human periodontal ligament stem cells (hPDLSCs). In the study, hPDLSCs were stimulated by LPS from Porphyromonas gingivalis to establish an in vitro inflammatory cellular model. Protein expression was measured using Western blotting. mRNA levels were evaluated by qRT-PCR. Cell viability, inflammatory cytokine production, and caspase-1 activity was measured with commercially available kits. Oxidative stress was assessed by examining reactive oxygen species and nitric oxide production. We found that PTX3 was upregulated in LPS-stimulated hPDLSCs. PTX3 overexpression aggravated LPS-induced cell viability loss, inflammatory cytokine production, and oxidative stress, as well as suppressed the osteogenic differentiation in hPDLSCs, while silencing PTX3 had the opposite effects. Further, PTX3 overexpression promoted NOD-like receptor family, pyrin domain containing protein 3 (NLRP3) inflammasome overactivation and pyroptosis, evidenced by increased protein levels of NLRP3, cleaved-caspase-1, apoptosis-associated speck-like protein (ASC), and N-terminal gasdermin D (GSDMD-N). Inhibition of NLRP3 inflammasome and/or caspase-1 partially attenuated the effects of PTX3 on LPS-stimulated hPDLSCs. This study indicated that PTX3 promotes LPS-induced pyroptosis and inflammation in hPDLSCs through activation of the caspase-1-dependent NLRP3 inflammasome.

[Pollution Characteristics and Evaluation of Heavy Metal Pollution in Surface Soil Around a Municipal Solid Waste Incineration Power Plant].

To investigate and evaluate the pollution levels of heavy metals in the soil around a large Municipal Solid Waste Incineration power plant (MSWIPP), a total of 29 soil samples were collected around the MSWIPP and away from the power plant area. The contents of 10 selected heavy metals (Cr, Mn, Ni, Cu, Zn, As, Ag, Cd, Hg, and Pb) were analyzed. The results showed that the content of each heavy metal element did not exceed the values for Soil Environmental Quality of Risk Control Standard for Soil Contamination of Agricultural Land (GB15618-2018) and Development Land (GB 36600-2018). The mean contents of Mn, Cu, and As were higher than their respective background values of Anhui Province, where As was 1.03 times the background value, and Cu was 1.07 times. Compared with the control points, the contents of Cr, Ni, Cd, Cu, and As were lower than the control points, and the difference was statistically significant (P ≤ 0.05). The spatial distribution of Hg was more obvious in the soil around the power plant, and other heavy metals were not obvious and uniform. The content of Hg was the highest in the 500 m soil of perennial dominant downwind and sub-dominant downwind. With increasing distance from the power plant, the content gradually decreased and it was lower than the level of the control point. The pollution degree of heavy metal elements in the soil around the power plant and in the plant area was mild. The Nemero comprehensive pollution index (PI) was 1.1-1.2, and the control point had also mild pollution (PI was 1.5). The potential ecological risk was slight, and the comprehensive potential ecological risk index (RI) of various heavy metal elements was 60.2-67.7. The contribution rate of Hg and As to RI were large, and the control point had medium ecological risk (RI was 116.8). Based on the results of principal component analysis, accompanied with the content, spatial distribution characteristics, Pearson's correlation, and hierarchical cluster analysis results, three groups of heavy metals with different spatial distribution were identified:①Ni, Cr, As, and Mn originated from lithological sources; ②Cu, Zn, Ag, Cd, and Pb affected by both lithological and human sources (e.g. agricultural and traffic sources); ③Hg likely originated from the diffusion sedimentation of MSWI flue gas and its accumulation in the soil. The above results indicated that the unique pollution characteristics of Hg deserve serious attention in pollution monitoring in soils surrounding solid waste incinerator.