Six new species of Margattea Shelford, 1911 (Blaberoidea, Pseudophyllodromiidae, Neoblattellini) from China.

Six Margattea species are established and described: three are cryptic species, namely, M.parabisignata Li & Che, sp. nov., M.semicircularis Li & Che, sp. nov., and M.forcipata Li & Che, sp. nov. They are distinguished from known species M.bisignata, M.spinifera, and M.paratransversa by their male genitalia with the aid of molecular species delimitation method (ABGD) using COI as the molecular marker. The other three new species are M.pedata Li & Che, sp. nov., M.undulata Li & Che, sp. nov., and M.bisphaerica Li & Che, sp. nov. Morphological and genitalia photographs of these new species of Margattea, as well as a key to the species of Margattea from China, are provided.

Non-stoichiometric molybdenum sulfide clusters and their reactions with the hydrogen molecule.

Structures of non-stoichiometric MoxSy clusters (x = 2-4; y = 2-10) were studied by density functional calculations with global optimization. Besides 1T phase like structures, a novel regular grid structure in which Mo atoms are well separated by S atoms was found, which might be used as a building-block to construct a new type of two-dimensional molybdenum sulfide monolayer. The hydrogen molecule prefers to be adsorbed onto Mo atoms rather than S atoms, and Mo atoms with less S coordination have a higher ability to adsorb H2. In addition, the reaction pathways for H2 dissociation were studied on two clusters with the highest H2 adsorption energy (Mo2S4 and Mo3S3). The vacant bridge site of Mo-Mo in S-deficient clusters, which corresponds to the sulfur vacancy in the bulk phase MoS2, is favored by H atom adsorption and plays an important role in the H atom transfer on MoxSy clusters. Our results provide a new aspect to understand the reason why S defect in MoS2 and MoS2 with an Mo-edge could enhance the catalytic performance in the hydrogen evolution reaction.

Simultaneous determination of liensinine, isoliensinine and neferine in rat plasma by UPLC-MS/MS and application of the technique to pharmacokinetic studies.

ETHNOPHARMACOLOGICAL RELEVANCE: The in vivo effects of traditional herbal medicines are generally mediated by multiple bioactive components. The main constituents of Lotus Plumule are alkaloids such as liensinine, isoliensinine and neferine. In this study, a simple, sensitive, and robust analytical method based on ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) has been developed for the determination of the three alkaloids in rat plasma using carbamazepine as internal standard (IS). MATERIALS AND METHODS: After precipitation of the proteins with acetonitrile, chromatography was performed on an Acquity UPLC BEH C18 column (2.1mm×50mm, 1.7µm particle size) using a gradient elution with 0.1% formic acid in water and acetonitrile. Mass spectrometry involved positive electrospray ionization and multiple reaction monitoring (MRM) of the transitions at m/z 611.7→206.2 for liensinine, 611.3→192.2 for isoliensinine, 625.2→206.1 for neferine and m/z 237.1→194.2 for IS. RESULTS: The method was linear over the concentration range 5-1000ng/mL with a lower limit of quantifof 5ng/mL for each alkaloid. Inter- and intra-day precision (RSD%) were all within 11.4% and the accuracy (RE%) were equal or lower than 10.4%. Recoveries were more than 75.3% and matrix effects were not significant. Stability studies showed that the three alkaloids were stable under a variety of storage conditions. CONCLUSION: The method was successfully applied to a pharmacokinetic study involving intravenous administration of liensinine, isoliensinine and neferine to rats.