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The height of the peak electron density (hmF2) and the critical frequency of the F2 layer (foF2) are very important in the research of ionospheric electrodynamics and high frequency (HF) wireless communication. In the article, we validated the hmF2/foF2 model values of the latest version of the International Reference Ionosphere (IRI-2016) with observations from three ionosonde stations which belong to low, middle, and high latitudes (i.e., Sanya, Beijing and Mohe) over China during a high solar activity year (2014, F10.7 = 145.9 sfu) and a low solar activity year (2016, F10.7 = 88.7 sfu). Among them, foF2 model values can be obtained through the International Radio Consulting Committee (CCIR) model or the International Union of Radio Science (URSI) model, both of which have the "F-peak storm model" on or 'off' options; hmF2 model values can be obtained through Bilitza-Sheikh-Eyfrig (BSE-1979), Altadill-Magdaleno-Torta-Blanch (AMTB-2013), or SHUbin (SHU-2015) model. The IRI-2016 hmF2/foF2 model values were evaluated by root mean square (RMS) values and mean absolute relative error (MARE). The results show that for the foF2 parameter, the performance of IRI-2016 can be improved by choosing "F-peak storm model" on option in geomagnetic-disturbed days. Whether in high or low solar activity years, for foF2, the IRI-2016 options of CCIR have better prediction ability than IRI-2016 options of URSI in low and high latitudes over China, and the IRI-2016 options of URSI have better prediction ability than IRI-2016 options of URSI in middle latitudes. For hmF2, the IRI-2016 option of SHU-2015 has better prediction ability than the IRI-2016 options of AMTB-2013 and BSE-1949 in high latitudes over China, the IRI-2016 options of SHU-2015 and BSE-1979 have better prediction ability than IRI-2016 options of AMTB-2013 in mid and low latitudes over China. [ABSTRACT FROM AUTHOR]

The Danjiangkou Reservoir (DJKR) is the freshwater source for the Middle Route of the South-to-North Water Diversion Project in China, and its water level and storage changes are important for water resource management. To maximize the potential capacity of the Gravity Recovery and Climate Experiment (GRACE) mission, an improved Lagrange multiplier method (ILMM) is first proposed to detect terrestrial water storage anomalies (TWSA) in the small-scale basin (DJKR). Moreover, for the first time, water diversion fingerprints are proposed to analyze the spatiotemporal pattern of the TWSA in the DJKR. The results indicate that the increased water level and storage signals due to the DJKR impoundment in 2014 can be effectively detected by using the ILMM, and they agree well with the results from altimetry and in situ data. Additionally, the water diversion fingerprints due to the DJKR impoundment are inferred, and describe the progression of spatiotemporal variability in water storage. The results show that water storage decreased in the upper Hanjiang River and increased in the DJKR as well as to the east of it during the period 2013–2015. Our research provides a scientific decision-making basis for monitoring the water resources of the DJKR and managing the South-to-North Water Diversion Project. [ABSTRACT FROM AUTHOR]

Endotoxic shock exhibits a considerably high mortality risk. It is defined as a systemic inflammatory response syndrome caused by a microbial infection. Radix Isatidis has anti-inflammatory, antiviral, and antipyretic effects and is used worldwide. This study investigated the antiendotoxin sepsis effects of an aqueous R. Isatidis extract (RIE) and explored the possible pharmacological molecular mechanisms. Male C57BL/6J mice were intravenously injected with 15 mg/kg lipopolysaccharide (LPS) to induce endotoxic shock. The results demonstrated that the survival rate of mice pretreated with RIE increased, and LPS-induced liver and lung damage were reduced by inhibiting inflammation. For elucidating detailed molecular mechanisms, we focused on LPS-induced transcription factors: nuclear factor-κB (NF-κB) and interferon regulatory factor 3 (IRF3). Our results demonstrated that the protective effects of RIE were strongly dependent on IRF3-induced interferon-β, not on NF-κB-induced tumor necrosis factor-α and interleukin-1β. In addition, RIE suppressed the phosphorylation of IRF3, not NF-κB. In conclusion, this study revealed the antiendotoxic properties of RIE on LPS-induced sepsis and provided mechanistic evidence for the beneficial effects of RIE. [ABSTRACT FROM AUTHOR]