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We study the coupled-top model with three large spins located on a triangle. Depending on the coupling strength, there exist three phases: disordered paramagnetic phase, ferromagnetic phase, and frustrated antiferromagnetic phase, which can be distinguished by the mean-field approach. The paramagnetic-ferromagnetic phase transition is accompanied by the breaking of the global $Z_2$ symmetry, whereas the paramagnetic-antiferromagnetic phase transition is accompanied by the breaking of both the global $Z_2$ symmetry and the translational symmetry. Exact analytical results of higher-order quantum effects beyond the mean-field contribution, such as the excitation energy, quantum fluctuation, and von Neumann entropy, can be achieved by the Holstein-Primakoff transformation and symplectic transformation in the thermodynamic limit. Near the quantum critical point, the energy gap closes, along with the divergence of the quantum fluctuation in certain quadrature and von Neumann entropy. Particular attention should be paid to the antiferromagnetic phase, where geometric frustration takes effect. The critical behaviors in the antiferromagnetic phase are quite different from those in the paramagnetic and ferromagnetic phases, which highlight the importance of geometric frustration. The triangular coupled-top model provides a simple and feasible platform to study the quantum phase transition and the novel critical behaviors induced by geometric frustration., Comment: 10 pages, 6 figures

Metabolomics based on ultra-high performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry(UHPLC-Q-TOF-MS) was employed to analyze the effect of Cyathulae Radix on serum and urine in rats with knee osteoarthritis, and to decipher the mechanism of Cyathulae Radix in the treatment of knee osteoarthritis. SD rats were randomized into a normal group, a model group, a positive drug group, and a Cyathulae Radix group. The knee osteoarthritis model was established by injecting 2% pa-pain and 0.03 mol·L~(-1) cysteine, and the serum levels of tumor necrosis factor-α(TNF-α) and matrix metalloproteinase-3(MMP-3) in the model group was measured to preliminarily evaluate the therapeutic effect of Cyathulae Radix on knee osteoarthritis. UHPLC-Q-TOF-MS was employed to establish the metabolic profile of endogenous small molecule metabolites in the four groups. Potential biomarkers were screened out by multivariate analysis methods such as partial least squares discriminant analysis(PLS-DA) and orthogonal partial least squares discriminant analysis(OPLS-DA) in combination with t-test, variable importance for projection(VIP), and fold-change. The related metabolic pathways were enriched with the help of MetaboAnalyst 5.0. The results showed that Cyathulae Radix alleviated the general signs of rats with knee osteoarthritis, and reduced the levels of TNF-α and MMP-3 in the rat serum. Twenty-eight differential metabolites that might be associated with the therapeutic effect of Cyathulae Radix were screened out from serum and urine. They were mainly involved in arginine biosynthesis, nicotinate and nicotinamide metabolism, tricarboxylic acid cycle, alanine, aspartate and glutamate metabolism, riboflavin metabolism, glyoxylate and dicarboxylate metabolism, and pyrimidine metabolism. Through metabonomics analysis, this study predicted the possible mechanism of Cyathulae Radix in the treatment of knee osteoarthritis, which laid a foundation for further research.

We study the ground state phase diagram of a one-dimensional two qubits Dicke-Hubbard model with XY qubit-qubit interaction. We use a numerical method combing the cluster mean-field theory and the matrix product state(MPS) to obtain the exact wave function of the ground state. When counter-rotating wave terms(CRTs) in the qubit-cavity coupling are neglected, we observe a rich phase diagram including a quantum phase transition between the Mott-insulating phase and the superfluid phase. This phase transition can be either the first-order or the second-order type depending on whether the total angular momentum changes across the phase diagram. Moreover, we observe two quantum triple points, at which three different phases coexist, with both positive and negative XY interactions. By further considering the effect of CRTs, we find that the main feature in the previous phase diagram, including the existence of quantum triple points, is retained. We also show that CRTs extremely demolish the non-local correlations in the coherent phase.

Phytochemical investigation of the 95% ethanol extract from Pinus yunnanensis Franch resin induced the isolation of six previously unreported diterpenoids pinuyunnanacids K - N, P - Q, a nor-diterpenoid with a novel skeleton pinuyunnanacid O and six known analogues. Their structures were elucidated by spectroscopic analysis and computational methods, including nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, calculated NMR chemical shifts method and electronic circular dichroic (ECD) spectra. All the compounds were analyzed for anti-inflammatory activity through western blotting and cell viability, compounds 2, 10 and 12 significantly downregulated the protein expression of iNOS at the concentration of 40 μM. At the same time, compounds 10 and 12 decreased the expression of COX-2 in LPS-treated RAW264.7 (leukemia cells in mouse macrophage) cells at the concentration of 40 μM.

Eight previously undescribed diterpenoids, rosins A-H, and nine known diterpenoids were isolated from the resin from Pinus kesiya var. langbianensis (A.Chev.) Gaussen ex Bui (Pinaceae) extracted with 95% ethanol. Their structures were determined by nuclear magnetic resonance spectroscopy, mass spectrometry, J-based configuration analysis (JBCA), NOESY spectra, calculated NMR chemical shifts and electronic circular dichroic (ECD) spectra. All compounds were evaluated for their protective effects in LPS-treated human normal lung epithelial cells (BEAS-2B), and the cell viability was significantly increased after treatment with compounds 5, 10, 12, or 15 at a concentration of 10 μM.

Five new compounds, named gingerol A (

Seven undescribed compounds, including a sesquiterpenoid derivative, a γ-lactone, four gingerols, and a dihydroferulic acid lactate were isolated from the rhizome of Zingiber officinale, and named gingerterpenoid G, gingerlactone A, zingibergingerols A-D and L-dihydroferulic acid lactate, respectively. Zingibergingerols (±)-B and (±)-C were two pairs of enantiomers. The structures of all compounds were determined by 1D-NMR, 2D-NMR and mass spectrometry. The absolute configurations were determined by comparison of the experimental and theoretically calculated ECD curves or X-ray single-crystal diffraction. Bioassay showed that gingerterpenoid G, gingerlactone A, and zingibergingerols A and B exhibited significant anti-inflammatory activity in the model of LPS-induced RAW 264.7 cells.

Five monoterpenoid compounds(1-5) were isolated and purified from the acetone fraction of the aqueous extract of Zingiberis Rhizoma Recens by MCI, Sephadex LH-20, silica gel, semi-preparative HPLC, and TLC. Their structures were identified with multiple spectroscopical methods including 1 D-NMR, 2 D-NMR, and MS. The five compounds were identified as(2E,6Z)-8-hydroxy-2,6-dimethylocta-2,6-dien-1-yl-(E)-3-(4-hydroxy-3-methoxyphenyl) acrylate(1),(2E,6E)-8-hydroxy-3,7-dimethylocta-2,6-die-noic acid(2),(E)-1,8-dihydroxy-3,7-dimethyl-2-octenoic acid(3), linalyl-β-D-glucopyranoside(4), and β-D-glucopyranoside-(2E)-3,7-dimethyl-2,6-octadien-1-yl(5), respectively.Compound 1 was a new monoterpene ester, and compounds 4-5 were isolated from this plant for the first time.

Four new diarylheptanoid glycosides (1-4), (1S,3R,5S)-2-(4-hydroxy-3- methoxyphenyl)-6-[2-(4-hydroxyphenyl)ethyl]-tetrahydropyran-4-ol-4'-O-β-D-glucopyranoside (1), (1S,3R,5S)-2-(4,5-dihydroxy-3-methoxyphenyl)-6-[2-(4-hydroxyphenyl) ethyl]-tetrahydropyran-4-ol-4'-O-β-D-glucopyranoside (2), (1S,3R,5S)-2-(4-hydroxy- 3,5-dimethoxyphenyl)-6-[2-(4-hydroxy-3-methoxyphenyl)ethyl]-tetrahydropyran-4-ol-4'-O-β-D-glucopyranoside (3), and (1R,3R,5R)-2-(4-hydroxy-3,5-dimethoxyphenyl)- 6-[2-(4-hydroxy-3-methoxyphenyl)ethyl]-tetrahydropyran-4-ol-3-O-β-D-glucopyranoside (4) were isolated from the 50% ethanol extract of Zingiber officinale peel. The structures of the isolated compounds were determined by HR-ESI-MS and extensive spectroscopic techniques (UV, IR, 1D-NMR, and 2D-NMR). Compounds 1-4 significantly increased the survival rate of human normal lung bronchial epithelial cells (BEAS-2B) induced by lipopolysaccharide (LPS) at the concentration of 10 μM.