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Seven new lanthanide coordination polymers, namely [Ln(cpt)3H2O)]n(Ln = La (1), Pr (2), Sm (3), Eu (4), Gd (5), Dy (6), and Er (7)), which were synthesized under hydrothermal conditions using 4′-(4-(4-carboxyphenyloxy)phenyl)-4,2′:6′,4′-tripyridine (Hcpt) as the ligand. The crystal structures of these seven complexes were determined using single-crystal X-ray diffraction, and they were found to be isostructural, crystallizing in the triclinic P1- space group. The Ln(III) ions were nine-coordinated with tricapped trigonal prism coordination geometry. The Ln(III) cations were coordinated by carboxylic and pyridine groups from (cpt)− ligands, forming one-dimensional ring-chain structures. Furthermore, the luminescent properties of complexes 1–7 were investigated using fluorescent spectra in the solid state. The fluorescence sensing experiments demonstrated that complex 4 exhibits high selectivity and sensitivity for detecting Co2+, Cu2+ ions, and nitrobenzene. Moreover, complex 3 shows good capability for detecting Cu2+ ions and nitrobenzene. Additionally, the sensing mechanism was also thoroughly examined through theoretical calculations.

Gas-liquid two-phase flow behavior in horizontal channel under heaving motion showed unique dynamic characteristics due to the complex nonlinear interaction. To further establish a description model and investigate the effects of heaving motion on horizontal gas-liquid flow, experiments in a wide range of vibration parameters and working conditions were carried out by combining vibration platform with two-phase flow loop. It was found that the flow regimes under heaving motion showed significant differences compared to the ones expected in steady state flow under the same working conditions. Increasing vibration parameters showed an obvious impact on fluctuation degree of gas-liquid interface by visualizing high-speed photographs. A method based on multi-scale entropy was applied to identify flow regimes and reveal the underlying dynamic characteristics by collecting signals of pressure-difference. The results indicated that the proposed method was effective to analyze gas-liquid two-phase flow transition in horizontal channel under heaving motion by incorporating information of flow condition and change rate of multi-scale entropy, which provided a reliable guide for flow pattern control design and safe operation of equipment. However, for slug-wave and boiling wave flow, an innovative method based on multi-scale marginal spectrum entropy showed more feasible for identification of transition boundary.

AbstractAim:Gambogic acid (GA) is the major active ingredient of gamboge, which is secreted from a Chinese traditional medicine, Garcinia hanburyi, which possesses potent antitumor activity. GA3, a new GA derivative, has been shown to possess better water solubility than GA. The aim of the present study was to examine the antitumor activity of GA3 and the mechanism underlying it.Methods:The growth inhibition of cancer cell lines induced by GA3 was assessed using the SRB assay. DAPI staining, flow cytometry, a DNA fragment assay, and Western blot analysis were used to study the apoptotic mechanisms of GA3.Results:GA3 displayed wide cytotoxicity in diversified human cancer cell lines with a mean IC50 value of 2.15 μmol/L. GA3 was also effective against multidrug resistant cells, with an average resistance factor (RF) that was much lower than that of the reference drug, doxorubicin. Mechanistic studies revealed that GA3-induced apoptosis in HL-60 cells proceeded via both extrinsic and intrinsic pathways, with caspase-8 functioning upstream of caspase-9. In addition, GA3-driven apoptotic events were associated with up-regulation of Bax, down-regulation of Bcl-2 and cleavage of Bid. Moreover, GA3 triggered cytochrome c release from the mitochondria, in particular bypassing the involvement of the mitochondrial membrane potential.Conclusion:Better solubility and a potential anti-MDR activity, combined with a comparable antitumor efficacy, make GA3 a potential drug candidate in cancer therapy that deserves further investigation.Acta Pharmacologica Sinica (2009) 30: 346–354; doi: 10.1038/aps.2009.3 [ABSTRACT FROM AUTHOR]