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This relation can be used to predict and select oxygen carriers with high CO2 splitting performance.Actinide chemistry appears to be a challenge for both experimentalists and theoreticians. Radioactivity and computational obstacles lead to a lack of heterogeneous data describing actinide compounds. Here we present a description of the first database devoted to ab initio actinide calculations. The database contains information about the structures and electronic properties of 87 actinide and 17 other compounds in the gas phase and is ready-to-use for benchmarking computational and experimental results or building new semiempirical models.Isocyanic acid (HNCO) is a potentially toxic atmospheric pollutant, whose atmospheric concentrations are hypothesized to be linked to adverse health effects. An earlier model study estimated that concentrations of isocyanic acid in China are highest around the world. However, measurements of isocyanic acid in ambient air have not been available in China. Two field campaigns were conducted to measure isocyanic acid in ambient air using a high-resolution time-of-flight chemical ionization mass spectrometer (ToF-CIMS) in two different environments in China. The ranges of mixing ratios of isocyanic acid are from below the detection limit (18 pptv) to 2.8 ppbv (5 min average) with the average value of 0.46 ppbv at an urban site of Guangzhou in the Pearl River Delta (PRD) region in fall and from 0.02 to 2.2 ppbv with the average value of 0.37 ppbv at a rural site in the North China Plain (NCP) during wintertime, respectively. These concentrations are significantly higher than previous measurements in North America. The diurnal variations of isocyanic acid are very similar to secondary pollutants (e.g., ozone, formic acid, and nitric acid) in PRD, indicating that isocyanic acid is mainly produced by secondary formation. Both primary emissions and secondary formation account for isocyanic acid in the NCP. The lifetime of isocyanic acid in a lower atmosphere was estimated to be less than 1 day due to the high apparent loss rate caused by deposition at night in PRD. Based on the steady state analysis of isocyanic acid during the daytime, we show that amides are unlikely enough to explain the formation of isocyanic acid in Guangzhou, calling for additional precursors for isocyanic acid. Our measurements of isocyanic acid in two environments of China provide important constraints on the concentrations, sources, and sinks of this pollutant in the atmosphere.Artificial aquaporins are synthetic molecules that mimic the structure and function of natural aquaporins (AQPs) in cell membranes. The development of artificial aquaporins would provide an alternative strategy for treatment of AQP-related diseases. In this report, an artificial aquaporin has been constructed from an amino-terminated tubular molecule, which operates in a unimolecular mechanism. The artificial channel can work in cell membranes with high water permeability and selectivity rivaling those of AQPs. Importantly, the channel can restore wound healing of the cells that contain function-lost AQPs.Doxorubicin (DOX) is a widely used classical broad-spectrum anticancer drug. selleckchem The major mechanism of DOX-mediated anticancer activity at clinically relevant concentrations is believed to be via DNA double-strand breaks due to topoisomerase IIα. However, other mechanisms by which DOX causes cytotoxicity have been proposed, including formaldehyde-dependent virtual interstrand cross-linking (ICL) formation. In this study, a method was established whereby cytotoxicity caused by virtual ICL derived from DOX is turned on and off using a cell culture system. Using this strategy, DOX-mediated cytotoxicity in Fanconi anemia group gene (FANC)/breast cancer susceptibility gene (BRCA)-deficient cells increased up to 70-fold compared to that in cells proficient in DNA repair pathways by increasing intracellular formaldehyde (FA) concentration. This approach also demonstrated that cytotoxicity introduced by DOX-mediated FA-dependent virtual ICL is completely independent of the toxicity induced by topoisomerase II inhibition at the cellular level. The potential of dual-targeting by DOX treatment was verified using an acid-specific FA donor. Overall, anticancer therapy targeting tumors deficient in the FANC/BRCA pathway may be possible by minimizing DOX-induced toxicity in normal cells.A series of quaternary and quinary Zintl phase thermoelectric (TE) compounds, Ca5-xYb x Al2-yIn y Sb6 (3.07(1) ≤ x ≤ 4.88(2); 0.16(2) ≤ y ≤ 2.00), containing Al/In mixed sites as well as Ca/Yb mixed sites has been successfully synthesized by a direct arc-melting method, and the X-ray diffraction analyses indicated that the products initially adopted an orthorhombic Ba5Al2Bi6-type structure (space group Pbam, Z = 2). However, after a postannealing process at 973 K for 1 month, the particular Yb rich compounds underwent a transformation of the original structure type to a Ca5Ga2Sb6-type phase regardless of the In substitution for Al. The noticeable site preference of cationic Ca and Yb in the three available cationic sites could be understood on the basis of a size match between the central cation and the volume of the anionic polyhedra. The observed phase transition was nicely explained by DFT calculations, proving that the Ca5Ga2Sb6-type phase was energetically more favorable than the Ba5Al2Sb6-type phase for the particular Yb-rich compound. Moreover, this energy difference between the two title phases was originally the result of both the site energy in the Ca site and the bond energies in the [(Al/In)2Sb8] anionic building blocks. A series of thermoelectric property data indicated that a two-step process involving a partial/full In substitution for Al and a phase transition from the Ba5Al2Sb6-type to the Ca5Ga2Sb6-type phase successfully enhanced the electrical conductivities and the Seebeck coefficients of the title compounds. This kind of combined effect eventually resulted in a ZT improvement for the quinary compound Ca1.14(2)Yb3.86Al1.68(1)In0.32Sb6 by approximately 4 times in comparison to its quaternary predecessor Ca1.55(1)Yb3.45Al2Sb6.