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The celebrated Kitaev honeycomb model provides an analytically tractable example with an exact quantum spin liquid ground state. While in real materials, other types of interactions besides the Kitaev coupling ($K$) are present, such as Heisenberg ($J$) and symmetric off-diagonal ($\mathrm{\ensuremath{\Gamma}}$) terms, these interactions can also be generalized to a triangular lattice. Here, we carry out a comprehensive study of the $J\ensuremath{-}K\ensuremath{-}\mathrm{\ensuremath{\Gamma}}$ model on a triangular lattice covering the whole parameter region, using a combination of exact diagonalization, classical Monte Carlo, and analytic methods, with an emphasis on the effects of the $\mathrm{\ensuremath{\Gamma}}$ term. In the HK limit ($\mathrm{\ensuremath{\Gamma}}=0$), we find five quantum phases which are quite similar to their classical counterparts. Among them, stripe-A and dual N\'eel phases are robust against the introduction of the $\mathrm{\ensuremath{\Gamma}}$ term, in particular, stripe A extends to the region connecting $K=\ensuremath{-}1$ and $K=1$ for $\mathrm{\ensuremath{\Gamma}}l0$. Though the ${120}^{\ensuremath{\circ}}$ N\'eel phase also extends to a finite $\mathrm{\ensuremath{\Gamma}}$, its region is largely reduced compared to the previous classical result. Interestingly, the ferromagnetic (dubbed FM-A) and stripe-B phases are unstable in response to an infinitesimal $\mathrm{\ensuremath{\Gamma}}$ interaction. Moreover, we find five additional phases for $\mathrm{\ensuremath{\Gamma}}\ensuremath{\ne}0$ which are elaborated by both the quantum and classical numerical methods. Part of the parameter space previously identified as the ${120}^{\ensuremath{\circ}}$ N\'eel phase in the classical study is found to give way to the modulated stripe phase. Depending on the sign of the $\mathrm{\ensuremath{\Gamma}}$ term, the FM-A phase transits into FM-B ($\mathrm{\ensuremath{\Gamma}}g0$) and FM-C ($\mathrm{\ensuremath{\Gamma}}l0$) phases with different spin orientations. Similarly, the stripe-B phase transits into stripe-C ($\mathrm{\ensuremath{\Gamma}}g0$) and stripe-A ($\mathrm{\ensuremath{\Gamma}}l0$) phases. Around the positive $\mathrm{\ensuremath{\Gamma}}$ point, due to the interplay of the Heisenberg, Kitaev, and $\mathrm{\ensuremath{\Gamma}}$ interactions, we find a possible quantum spin liquid in a noticeable region with a continuum in spin excitations.

Correlated states emerge in low-dimensional systems owing to enhanced Coulomb interactions. Elucidating these states requires atomic scale characterization and delicate control capabilities. In this study, spectroscopic imaging-scanning tunneling microscopy was employed to investigate the correlated states residing in the one-dimensional electrons of the monolayer and bilayer MoSe2 mirror twin boundary (MTB). The Coulomb energies, determined by the wire length, drive the MTB into two types of ground states with distinct respective out-of-phase and in-phase charge orders. The two ground states can be reversibly converted through a metastable zero-energy state with in situ voltage pulses, which tunes the electron filling of the MTB via a polaronic process, as substantiated by first-principles calculations. Our modified Hubbard model reveals the ground states as correlated insulators from an on-site U-originated Coulomb interaction, dubbed Hubbard-type Coulomb blockade effect. Our work sets a foundation for understanding correlated physics in complex systems and for tailoring quantum states for nano-electronics applications., Comment: 4 figures, 19 pages

We introduce an entanglement entropy analysis to quantitatively identify the confinement and deconfinement of the spinons in the spin excitations of quantum magnets. Our proposal is implemented by the parton construction of a honeycomb-lattice antiferromagnet exhibiting high-energy anomalous spectra. To obtain the quasiparticles of spin excitations for entanglement entropy calculations, we develop an effective Hamiltonian using the random phase approximation. We elaborate quantitatively the deconfinement-to-confinement transition of spinons in the anomalous spectra with the increase of the Hubbard interaction, indicating the avoided fractionalization of magnons in the strong interaction regime. Meanwhile, the Higgs mode at the {\Gamma}0 point is fractionalized into four degenerate spinon pairs, although it appears as a sharp well-defined peak in the spectra. Our work extends our understanding of the deconfinement of the spinon and its coexistence with the magnon in quantum magnets., Comment: 6 pages, 4 figures

To explore the possible risk factors of death in children with acute lymphoblastic leukemia (ALL) after treatment.The clinical data of 31 children with newly diagnosed acute lymphoblastic leukemia and dead after treatment in the Hematology Oncology Department of Wuhan children's Hospital from January 1, 2016 to December 31, 2019 were retrospectively analyzed. Univariate factor analysis and multivariate Cox regression analysis were used to analyze the each indexes of ALL children, and the possible risk factors causes of death in ALL children after treatment were analyzed.Among 230 newly diagnosed ALL children, 31 (13.4%) cases were dead. Among them, there were 12 male and 19 female. The mortality rates were 9%(12/133) for male and 19.5%(19/97) for female, which showed a significantly difference（P=0.02）； among the dead ALL children, 6 were less than 1 year old, 23 were 1-10 years old, and 2 was more than 10 years old. The mortality rates in different age groups were 46.1 % (6/13), 11.7%(23/195) and 9%(2/22), respectively, which showed a significantly difference（P=0.00）； the mortality rates of the ALL children in standard risk group, medium risk group and high risk group were 6.7% (4/59), 11.9% (13/10The female, less than 1 year old at initial diagnosis, high risk ALL, WBC50×10初诊儿童急性淋巴细胞白血病治疗相关死亡的危险因素的分析.探讨儿童急性淋巴细胞白血病（acute lymphoblastic leukemia，ALL）患儿接受治疗后发生死亡的可能危险因素.回顾性分析2016年1月1日至2019年12月31日在武汉儿童医院血液肿瘤科初诊且接受治疗后死亡的31例ALL患儿的临床资料，对ALL患儿各项观察指标行单因素分析及多因素Cox回归分析，并分析ALL患儿接受治疗后死亡的可能危险因素.共有230例初诊ALL患儿接受治疗，31例死亡(13.4%），其中男12例，女19例。不同性别的死亡率分别为9%（12/133）、19.5%（19/97）(P=0.02)；死亡患儿中，年龄1岁6例，1-10岁23例，10岁2例，不同年龄组死亡率分别为46.1%（6/13）、11.7%（23/195）和9%（2/22）(P=0.00)；标危组、中危组、高危组的死亡率分别为6.7%（4/59）、11.9%（13/10女性、初诊时年龄1岁、高危ALL、初诊WBC50×10

We show that a conical magnetic field ${\bf H}=(1,1,1)H$ can be used to tune the topological order and hence anyon excitations of the $\mathrm{Z_2}$ quantum spin liquid in the isotropic antiferromagnetic Kitaev model. A novel topological order, featured with Chern number $C=4$ and Abelian anyon excitations, is induced in a narrow range of intermediate fields $H_{c1}\leq H\leq H_{c2}$. On the other hand, the $C=1$ Ising-topological order with non-Abelian anyon excitations, is previously known to be present at small fields, and interestingly, is found here to survive up to $H_{c1}$, and revive above $H_{c2}$, until the system becomes trivial above a higher field $H_{c3}$. The results are obtained by devoloping and applying a $\mathrm{Z_2}$ mean field theory, that works at zero as well as finite fields, and the associated variational quantum Monte Carlo., Comment: 5 pages, 3 color figures

The liquid desiccant air-conditioning system allows reducing energy consumption compared to the conventional compressor-type air conditioners. In order to develop desiccant materials for air conditioners, we have investigated the dehumidification capability of quaternary ammonium Ionic Liquids (ILs) and the equilibrium water vapor pressure of aqueous solutions of these ammonium salts. Among the seven tested types of ILs, 2-hydroxy-N,N,N-trimethylethan-1-aminium dimethylphosphate ([Ch][DMPO4]) displayed the best dehumidification capability and the lowest equilibrium water vapor pressure. Furthermore, the 80% aqueous solution of [Ch][DMPO4] exhibited a less corrosive effect on four types of metals, i.e., steel (hot dip zinc-aluminum alloy plated steel), copper (C1100P), aluminum (A5052), and stainless steel (SUS: SUS304). It should be noted that this [Ch][DMPO4] is not only non-toxic but also exhibits a stable nature; the aqueous solution produced no odor after storing for over 1 year under ambient conditions., Graphical abstract We found that 2-hydroxy-N,N,N-trimethylethan-1-aminium dimethylphosphate ([Ch][DMPO4]) exhibited excellent dehumidification capability with a high dehumidification rate. We strongly expect that the liquid desiccant-type air conditioner using the [Ch][DMPO4] aqueous solution might contribute to avoiding an outbreak of a new type of corona virus infection in the near future.Image 1

Background Idiopathic pulmonary fibrosis is a chronic, progressive, fibrotic disease. Although the pathogenesis remains unclear, the effect of endoplasmic reticulum (ER) stress in type II alveolar epithelial cells (AEC IIs) is increasingly thought to be a critical mechanism. Purpose We investigated the effects of citrus alkaline extracts (CAE) on AEC IIs and elucidated the underlying mechanism for their possible use in ameliorating pulmonary fibrosis (PF). Methods A bleomycin-induced mouse model of PF, and an in vitro tunicamycin (TM) -induced ER stress model in A549 cells were successfully established. Accumulation of collagen in lung tissues in vivo was assessed using histological analysis and western blotting. The expression levels of the ER-stress marker BiP and other related proteins were assessed by western blotting and immunofluorescence staining. Mitochondrial membrane potential was assessed to evaluate mitochondrial homeostasis. Results CAE mitigated collagen deposition to ameliorate PF in vivo. CAE suppressed the bleomycin or TM-induced increases in ER-stress biomarker, BiP, and PERK pathway proteins, resulting in a decrease in ER stress in mouse lung tissues and A549 cells, respectively. Additionally, CAE treatment suppressed the bleomycin or TM-induced increase in the ER-stress downstream proteins, activating ATF3 and increased the levels of PINK1 in AEC IIs, both in vivo and in vitro. The reduced mitochondrial homeostasis induced by TM was restored by CAE-treatment in A549 cells. Furthermore, conditioned media from TM-treated A549 cells increased collagen deposition in MRC5 cells mainly via TGF-β1. The increased collagen deposition was not seen using conditioned media from CAE-treated A549 cells. Conclusion These results provide novel insights into the potential mechanism of CAE in inhibiting ER stress in AEC IIs, and suggests that it has great potential to ameliorate PF via the ATF3/PINK1 pathway.

The elementary excitations from the conventional magnetic ordered states, such as ferromagnets and antiferromagnets, are magnons. Here, we elaborate a case where the well-defined magnons are absent completely and the spin excitation spectra exhibit an entire continuum in the itinerant edge ferromagnetic state of graphene arising from the flatband edge electronic states. Based on the further studies of the entanglement entropy and finite-size analysis, we show that the continuum other than the Stoner part results from the spin-1/2 spinons deconfined from magnons. The spinon continuum in a magnetically ordered state is ascribed to a ferromagnetic Luttinger liquid in this edge ferromagnet. The investigation is carried out by using the numerical exact diagonalization method with a projection of the interacting Hamiltonian onto the flat band., 7 pages, 7 figures

We perform thermodynamic and inelastic neutron scattering (INS) measurements to study the lattice dynamics (phonons) of a cubic collinear antiferromagnet Cu$_3$TeO$_6$ which hosts topological spin excitations (magnons). While the specific heat and thermal conductivity results show that the thermal transport is dominated by phonons, the deviation of the thermal conductivity from a pure phononic model indicates that there is a strong coupling between magnons and phonons. In the INS measurements, we find a mode in the excitation spectra at 4.5 K, which exhibits a slight downward dispersion around the Brillouin zone center. This mode disappears above the N\'{e}el temperature, and thus cannot be a phonon. Furthermore, the dispersion is distinct from that of a magnon. Instead, it can be explained by the magnon-polaron mode, which is new collective excitations resulting from the hybridization between magnons and phonons. We consider the suppression of the thermal conductivity and emergence of the magnon-polaron mode to be evidence for magnon-phonon coupling in Cu$_3$TeO$_6$., Comment: 9 pages, 4 figures, formula Cu3TeO6 updated in the title and abstract

Dirac matters provide a platform for exploring the interplay of their carriers with other quantum phenomena. ${\mathrm{Sr}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{1\ensuremath{-}y}{\mathrm{Sb}}_{2}$ has been proposed to be a magnetic Weyl semimetal and provides an excellent platform to study the coupling between Weyl fermions and magnons. Here, we report comprehensive inelastic neutron scattering (INS) measurements on single crystals of ${\mathrm{Sr}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{1\ensuremath{-}y}{\mathrm{Sb}}_{2}$, which have been well characterized by magnetization and magnetotransport measurements, both of which demonstrate that the material is a topologically nontrivial semimetal. The INS spectra clearly show a spin gap of $\ensuremath{\sim}6$ meV. The dispersion in the magnetic Mn layer extends up to about 76 meV, while that between the layers has a narrow band width of 6 meV. We find that the linear spin-wave theory using a Heisenberg spin Hamiltonian can reproduce the experimental spectra with the following parameters: a nearest-neighbor ($S{J}_{1}\ensuremath{\sim}28.0$ meV) and next-nearest-neighbor in-plane exchange interaction ($S{J}_{2}\ensuremath{\sim}9.3$ meV), interlayer exchange coupling ($S{J}_{c}\ensuremath{\sim}\ensuremath{-}0.1$ meV), and spin anisotropy constant ($SD\ensuremath{\sim}\ensuremath{-}0.07$ meV). Despite the coexistence of Weyl fermions and magnons, we find no clear evidence that the magnetic dynamics are influenced by the Weyl fermions in ${\mathrm{Sr}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{1\ensuremath{-}y}{\mathrm{Sb}}_{2}$, possibly because that the Weyl fermions and magnons reside in the Sb and Mn layers separately, and the interlayer coupling is weak due to the quasi-two-dimensional nature of the material, as also evident from the small $S{J}_{c}$ of $\ensuremath{-}0.1$ meV.

Background In China, lack of evidence remains a significant challenge for the national initiative to promote physical activity (PA). We aimed to quantify the beneficial effects of meeting or maintaining the recommended PA level [150 minutes per week (min/wk) of moderate PA or 75 min/wk of vigorous PA or an equivalent combination] on incident cardiovascular disease (CVD) among Chinese population. Methods We included 100,560 participants without history of CVD from three cohorts in the Prediction for Atherosclerotic Cardiovascular Disease Risk in China (China-PAR) project. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for CVD events and its subtypes, including stroke, coronary heart disease, heart failure, and CVD death. Results During a median follow-up of 7.3 years (range: 6–15 years), 777,163 person-years and 4693 incident CVD events were observed. Compared with participants who were inactive at baseline, the multivariable adjusted HR (95% CI) of developing CVD was 0.74 (0.69–0.79) for those who met recommended moderate to vigorous physical activity (MVPA) level at baseline. Furthermore, the risk of CVD incidence was reduced with increment of MVPA (Ptrend < 0.001), and the HR (95% CI) of highly-active versus inactive category was 0.62 (0.56–0.68). Compared with individuals who were inactive both at the baseline and follow-up, those keeping active over the period of follow-up had a substantial lower risk of incident CVD with the HR (95% CI) of 0.57 (0.43–0.77). Conclusions The findings demonstrated that meeting and maintaining the recommended MVPA level could reduce the cardiovascular risk. Wider adoption of the PA recommendations would have considerable health impacts to the Chinese population.

Motivated by the recent measurements of the spatial distribution of single particle excitation states in a hole-doped Mott insulator, we study the effects of impurity on the in-gap states, induced by the doped holes, in the Hubbard model on the square lattice by the cluster perturbation theory. We find that a repulsive impurity potential can move the in-gap state from the lower Hubbard band towards the upper Hubbard band, providing a good account for the experimental observation. The distribution of the spectral function in the momentum space can be used to discriminate the in-gap state induced by doped holes and that by the impurity. The spatial characters of the in-gap states in the presence of two impurities are also discussed and compared to the experiment.

The unexpected formation of a 4-hydroxytetrahydroquinolin-2(1H)-one from a bicyclo[3.3.1]nonanetrione system and an amino alcohol in the presence of TsOH is reported. The mechanism of this transformation was studied by DFT calculations. The reaction provides an entry to the synthesis of highly functionalized 4-hydroxytetrahydroquinolin-2(1H)-ones.

Topological magnons are emergent quantum spin excitations featured by magnon bands crossing linearly at the points dubbed nodes, analogous to fermions in topological electronic systems. Experimental realization of topological magnons in three dimensions has not been reported so far. Here, by measuring spin excitations (magnons) of a three-dimensional antiferromagnet Cu$_{3}$TeO$_{6}$ with inelastic neutron scattering, we provide direct spectroscopic evidence for the coexistence of symmetry-protected Dirac and triply degenerate nodes, the latter involving three-component magnons beyond the Dirac-Weyl framework. Our theoretical calculations show that the observed topological magnon band structure can be well described by the linear-spin-wave theory based on a Hamiltonian dominated by the nearest-neighbour exchange interaction $J_1$. As such, we showcase Cu$_{3}$TeO$_{6}$ as an example system where Dirac and triply degenerate magnonic nodal excitations coexist, demonstrate an exotic topological state of matter, and provide a fresh ground to explore the topological properties in quantum materials., Version as published in Nature Communications

Background: Residual SYNTAX score (rSS) and its derived indexes including SYNTAX revascularization index (SRI) and clinical rSS had been developed to quantify and describe the extent of incomplete revascularization. This study was conducted to explore the utility of the three scores among real-world patients after percutaneous coronary intervention (PCI). Methods: From January 2013 to December 2013, patients underwent PCI treatment at Fuwai Hospital were included. The primary endpoints were all-cause death and major adverse cardiovascular and cerebrovascular events. The secondary endpoints were myocardial infarction, revascularization, stroke, and stent thrombosis. Kaplan-Meier methodology was used to determine the outcomes. Cox multivariable regression was to test the associations between scores and all-cause mortality. Results: A total of 10,344 patients were finally analyzed in this study. Kaplan-Meier survival analysis indicated that greater residual coronary lesions quantified by rSS and its derived indexes were associated with increased risk of adverse cardiovascular events. However, after multivariate analysis, only clinical rSS was an independent predictor of 2-year all-cause death (hazard ratio: 1.02, 95% confidence interval: 1.01–1.03, P< 0.01). By receiver operating characteristic (ROC) curve analysis, clinical rSS had superior predictability of 2-year all-cause death than rSS and SRI (area under ROC curve [AUC]: 0.59 vs. 0.56 vs. 0.56, all P< 0.01), whereas rSS was superior in predicting repeat revascularization than clinical rSS and SRI (AUC: 0.62 vs. 0.61 vs. 0.61; all P< 0.01). When comparing the predictive capability of rSS ≥8 with SRI

Tb3+/Eu3+co-doped sodium nepheline transparent glass ceramics with the weight percentage composition of 27Na2O-19Al2O3-23SiO2-13H3BO3-6TiO2-6ZrO2-3Tb4O7-3Eu2O3were prepared by melting crystallization method. The heat treatment system, crystal phase, micromorphology, transmittance and luminescent properties of the samples were tested and characterized by DSC, XRD, SEM, UV-Vis-NIR and fluorescence spectrometer, respectively. The results show that the optimum heat treatment condition of glass at 480°C nucleated 1h and 580°C grew 1h., the crystal phase was NaAlSiO4(35-0424), and the incorporation of rare earth ions did not affect the crystal phase. The transmittance of glass ceramics in the visible area can reach 78%. The effect of different Tb3+/Eu3+doping concentration on the luminescent properties of glass ceramic samples was discussed. It was found that there was a phenomenon of Tb3+to Eu3+energy transfer, and the luminescence effect was best when the percentage of mass of Tb3+/Eu3+was 1:1.

Background: The patterns of nonadherence to antiplatelet regimen in stented patients (PARIS) thrombotic risk score are a novel score for predicting the risk of coronary thrombotic events (CTEs) after percutaneous coronary intervention (PCI) with drug-eluting stents. However, the prognostic value of this score has not been fully evaluated in non-Euro-American PCI populations. Methods: We performed a prospective, observational study of 10,724 patients who underwent PCI in Fuwai hospital, China and evaluated the PARIS thrombotic risk score’s predictive value of CTEs in the PCI population. The area under the receiver operating characteristic curve (AUROC) was used to assess the predictive value of the PARIS score for CTE. Results: Among 9782 patients without in-hospital events, a total of 95 CTEs occurred during the 2-year follow-up. The PARIS score was significantly higher in patients with CTEs (3.38 ± 2.04) compared with patients without events (2.53 ± 1.70, P < 0.001). According to the risk stratification of the PARIS thrombotic score, the risk of CTEs in the high-risk group was 3.14 times higher than that in the low-risk group (hazard ratio [HR], 3.14; 95% confidence interval [CI], 1.92–5.13; P < 0.001). However, the risk of CTEs in the intermediate-risk and low-risk groups was not significant (HR, 1.39; 95% CI, [0.86–2.24]; P = 0.184). The PARIS score showed prognostic value in evaluating CTEs in the overall population (AUROC, 0.621; 95% CI, 0.561–0.681), the acute coronary syndrome (ACS) population (AUROC, 0.617; 95% CI, 0.534–0.700; P = 0.003), and the non-ACS population (AUROC, 0.647; 95% CI, 0.558–0.736; P = 0.001). Conclusions: In a real-world Chinese population, the PARIS thrombotic risk score shows a modest prognostic value for CTEs in patients after PCI. This score also has a predictive value for CTEs in the ACS and non-ACS subgroup populations. Key words: Coronary Thrombosis; Percutaneous Coronary Intervention; Prognosis; Risk Assessment

Background: There is scanty evidence concerning the ability of Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes with Early Implementation of the ACC/AHA Guidelines (CRUSADE) and Acute Catheterization and Urgent Intervention Triage Strategy and Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (ACUITY-HORIZONS) scores to predict out-of-hospital bleeding risk after percutaneous coronary interventions (PCIs) with drug-eluting stents (DES) in patients receiving dual antiplatelet therapy. We aimed to assess and compare the long-term prognostic value of these scores regarding out-of-hospital bleeding risk in such patients. Methods: We performed a prospective observational study of 10,724 patients undergoing PCI between January and December 2013 in Fuwai Hospital, China. All patients were followed up for 2 years and evaluated through the Fuwai Hospital Follow-up Center. Major bleeding was defined as Types 2, 3, and 5 according to Bleeding Academic Research Consortium Definition criteria. Results: During a 2-year follow-up, 245 of 9782 patients (2.5%) had major bleeding (MB). CRUSADE (21.00 [12.00, 29.75] vs. 18.00 [11.00, 26.00], P < 0.001) and ACUITY-HORIZONS (9.00 [3.00, 14.00] vs. 6.00 [3.00, 12.00], P < 0.001) risk scores were both significantly higher in the MB than non-MB groups. Both scores showed a moderate predictive value for MB in the whole study cohort (area under the receiver-operating characteristics curve [AUROC], 0.565; 95% confidence interval [CI], 0.529–0.601, P = 0.001; AUROC, 0.566; 95% CI, 0.529–0.603, P < 0.001, respectively) and in the acute coronary syndrome (ACS) subgroup (AUROC: 0.579, 95% CI: 0.531–0.627, P = 0.001; AUROC, 0.591; 95% CI, 0.544–0.638, P < 0.001, respectively). However, neither score was a significant predictor in the non-ACS subgroup (P > 0.05). The value of CRUSADE and ACUITY-HORIZONS scores did not differ significantly (P > 0.05) in the whole cohort, ACS subgroup, or non-ACS subgroup. Conclusions: CRUSADE and ACUITY-HORIZONS scores showed statistically significant but relatively limited long-term prognostic value for out-of-hospital MB after PCI with DES in a cohort of Chinese patients. The value of CRUSADE and ACUITY-HORIZONS scores did not differ significantly (P > 0.05) in the whole cohort, ACS subgroup, or non-ACS subgroup.

Osteoporotic treatments have largely depended on antiresorptive or anabolic drugs; but the former also suppresses new bone formation, and the latter only includes human parathyroid hormone. There is no drug that has a dual effect to inhibit bone resorption and to stimulate bone formation simultaneously. Here, we report a small molecule, a quinoxaline derivative of oleanolic acid (QOA-8a) that plays such dual roles in osteoblasts and osteoclasts in the treatment of osteoporosis. Osteoclast differentiation was induced by incubation of primary mouse bone marrow-derived macrophages in the presence of RANKL and M-CSF, treatment with QOA-8a dose-dependently inhibited the osteoclast formation with an IC50 value of 0.098 μmol/L. QOA-8a also directly acted on osteoblasts, and stimulated new bone formation in murine calvarial bones in vitro and in vivo. In an OVX rat model, administration of QOA-8a (1, 5 mg·kg−1·d−1, po) for 16 weeks effectively prevented OVX-induced bone loss, accompanied by decreased serum levels of the bone resorption marker CTX-1 and increased serum levels of osteoblast marker N-MID-OT. Meaningfully, our preliminary study revealed that QOA-8a down-regulated the ERK1/2 signal in osteoclasts and up-regulated the signal in osteoblasts. QOA-8a showed dual functions in both animal and human osteoclastogenesis and osteoblastogenesis. Our results demonstrate that QOA-8a might serve as a lead compound with a dual function of bone anabolic and anti-resorptive effects in the development of anti-osteoporosis agents.

Lipid metabolic disorders and oxidative stress in the liver are key steps in the progression of nonalcoholic fatty liver disease (NAFLD), which is a major risk factor for the development of metabolic syndrome. To date, no pharmacological treatment for this condition has been approved. Our previous study has found that the food-derived compound apigenin (Api) significantly attenuates obesity-induced metabolic syndrome by acting as a peroxisome proliferator-activated receptor gamma modulator (PPARM). Herein, a high fat diet (HFD) induced NAFLD model was used to dig out whether Api had the effect on NAFLD. The results showed that Api had obvious effect in restraining NAFLD progression, including attenuating HFD induced lipid accumulation and oxidative stress in vivo. As a PPARM, although Api did significantly inhibit the expression of PPARγ target genes encoding the protein associated with lipid metabolism, it had no obvious activating effect on PPARγ. Interestingly, we found that Api promoted Nrf2 into the nucleus, thereby markedly activating Nrf2 to inhibit the lipid metabolism related genes and increase the oxidative stress related genes. Further Nrf2 knockdown/knockout and overexpression experiments showed that Api regulating PPARγ target genes was dependent on Nrf2 activation and the activation of Nrf2 counteracted the activation effect of PPARγ by Api. Importantly, we also found that Api might bind with Nrf2 via auto dock and ITC assay. Therefore, our results indicate that Api ameliorates NAFLD by a novel regulating mode of Nrf2 and PPARγ in inhibiting lipid metabolism and oxidative stress abnormity.

Both shear and tensile measurement methods have been used to quantify interfacial bonding strength of bilayer tablets. The shear method is more convenient to perform, but reproducible strength data requires careful control of the placement of tablet and contact point for shear force application. Moreover, data obtained from the shear method depend on the orientation of the bilayer tablet. Although more time-consuming to perform, the tensile method yields data that are straightforward to interpret. Thus, the tensile method is preferred in fundamental bilayer tableting research to minimize ambiguity in data interpretation. Using both shear and tensile methods, we measured the mechanical strength of bilayer tablets made of several different layer combinations of lactose and microcrystalline cellulose. We observed a good correlation between strength obtained by the tensile method and carefully conducted shear method. This suggests that the shear method may be used for routine quality test of bilayer tablets during manufacturing because of its speed and convenience, provided a protocol for careful control of the placement of the tablet interface, tablet orientation, and blade is implemented.

Five new triterpenoid saponin glycosides, trichocucumerisides A-E (1-5), together with eleven known compounds (6-16) were isolated from

Kitaev quantum spin liquids described by the Kitaev model represent an exotic state of matter with long-range entangled spins and topological order, which hold promise for quantum computation. $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{RuCl}}_{3}$, a material with van der Waals layered structure, is shown to be proximate to such a state recently. Here we report Raman spectroscopy of atomically thin $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{RuCl}}_{3}$. New phonon modes emerge at low temperature, signifying a phase transition to a crystal structure with lowered symmetry. The Fano line shape of two low-energy phonon modes and the magnetic scattering continuum in bulk $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{RuCl}}_{3}$, which evidence fractionalized Majorana fermions of the proximate quantum spin liquid, persist to the trilayer. Polarization-dependent measurements reveal increased anisotropy of the Kitaev exchange constants when approaching the two-dimensional limit. Our results demonstrate an intimate relation between the crystal structure and the symmetry of the proximate quantum spin liquid ground state.

Quantum spin liquids (QSLs) are an exotic state of matter that is subject to extensive research. However, the relationship between the ubiquitous disorder and the QSL behaviors is still unclear. Here, by performing comparative experimental studies on two kagom\'{e}-lattice QSL candidates, Tm$_3$Sb$_3$Zn$_2$O$_{14}$ and Tm$_3$Sb$_3$Mg$_2$O$_{14}$, which are isostructural to each other but with strong and weak structural disorder, respectively, we show unambiguously that the disorder can induce spin-liquid-like features. In particular, both compounds show dominant antiferromagnetic interactions with a Curie-Weiss temperature of -17.4 and -28.7 K for Tm$_3$Sb$_3$Zn$_2$O$_{14}$ and Tm$_3$Sb$_3$Mg$_2$O$_{14}$, respectively, but remain disordered down to about 0.05 K. Specific heat results suggest the presence of gapless magnetic excitations characterized by a residual linear term. Magnetic excitation spectra obtained by inelastic neutron scattering (INS) at low temperatures display broad continua. All these observations are consistent with those of a QSL. However, we find in Tm$_3$Sb$_3$Zn$_2$O$_{14}$ which has strong disorder resulting from the random mixing of the magnetic Tm$^{3+}$ and nonmagnetic Zn$^{2+}$, that the low-energy magnetic excitations observed in the specific heat and INS measurements are substantially enhanced, compared to those of Tm$_3$Sb$_3$Mg$_2$O$_{14}$ which has much less disorder. We believe that the effective spins of the Tm$^{3+}$ ions in the Zn$^{2+}$/Mg$^{2+}$ sites give rise to the low-energy magnetic excitations, and the amount of the random occupancy determines the excitation strength. These results provide direct evidence of the mimicry of a QSL caused by disorder., Comment: Version as published in PRB, 5 figures, 11 pages

OBJECTIVES To assess the predictive value of the Global Registry of Acute Coronary Events (GRACE) discharge score for patients with stable coronary artery disease (SCAD) after percutaneous coronary intervention (PCI). BACKGROUND The GRACE score is widely used for predicting the mortality of acute coronary syndrome patients. However, the predictive value of SCAD has not been sufficiently studied. METHODS We studied 4,293 consecutive patients with SCAD who underwent PCI between January 2013 and December 2013. The primary endpoint was all-cause mortality and the secondary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE). RESULTS Among 3,915 patients with SCAD following PCI, there were 38 deaths and 394 MACCE during 2 years of follow-up. The GRACE discharge score was significantly higher for patients who died than for those who survived (86.97 ± 23.27 vs. 71.07 ± 19.84; p

Prostate cancer (PCa) is the second leading cause of death in men, and current studies have shown that circular RNAs (circRNAs) play important roles in its occurrence and development. Detection of circRNAs in PCa cells showed that circ_KATNAL1 is down-regulated, mainly located in the cytoplasm, and contains multiple binding sites of miR-145-3p, which is an anticancer miRNA. RNA immunoprecipitation with anti-AGO2 antibody, RNA pull-down assays with biotin-labeled circ_KATNAL1 probe or an miR-145-3p mimic, and dual luciferase reporter gene assays confirmed that circ_KATNAL1 binds directly to miR-145-3p in cells, and that WISP1, which is highly expressed in many types of tumors, is an important target gene of miR-145-3p. Circ_KATNAL1 and miR-145-3p promote each other’s expression, and down-regulate the expression of the target gene WISP1. Both circ_KATNAL1 and miR-145-3p inhibit cell proliferation, invasiveness, and migration, down-regulate the expression of MMP-2 and MMP-9, promote cell apoptosis and the activation of caspase-3, caspase-8, caspase-9, and PARP, whereas WISP1 has the opposite effect, and the above-mentioned functions of circ_KATNAL1 were achieved through the miR-145-3p/WISP1 pathway. Therefore, circ_KATNAL1 plays an anticancer role in PCa cells through the miR-145-3p/WISP1 pathway, which could be an important target for the diagnosis and treatment of PCa.

Metallization of 1T-TaS_{2} is generally initiated at the domain boundary of a charge density wave (CDW), at the expense of its long-range order. However, we demonstrate in this study that the metallization of 1T-TaS_{2} can be also realized without breaking the long-range CDW order upon surface alkali doping. By using scanning tunneling microscopy, we find the long-range CDW order is always persisting, and the metallization is instead associated with additional in-gap excitations. Interestingly, the in-gap excitation is near the top of the lower Hubbard band, in contrast to a conventional electron-doped Mott insulator where it is beneath the upper Hubbard band. In combination with the numerical calculations, we suggest that the appearance of the in-gap excitations near the lower Hubbard band is mainly due to the effectively reduced on-site Coulomb energy by the adsorbed alkali ions.

Purpose: To determine whether covered or uncovered stent insertion achieved better clinical efficacy when used to treat malignant superior vena cava (SVC) obstruction (SVCO).Material and methods: A...

The occurrence and development of prostate cancer (PCa) is complex, and the related mechanism is not fully understood. Current studies have found that extracellular vesicles (EVs) and circular RNAs (circRNAs) have important functions in various tumours and other diseases. In this study, the detection of circRNAs in PCa showed that circ_SLC19A1 was increased in PCa cells and their secreted EVs. EVs with high expression of circ_SLC19A1 could be taken up by PCa cells, which promoted cell proliferation and invasion. The sequence of circ_SLC19A1 contained multiple binding sites for miR-497, and circ_SLC19A1 could bind directly to miR-497 in cells. The expression of miR-497 was downregulated in PCa cells, while the expression of its target gene septin 2 (SEPT2) was upregulated significantly. Transfection of circ_SLC19A1 small interfering RNA (siRNA) or miR-497 mimics could significantly inhibit the expression of SEPT2 and the phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2). After co-transfection of circ_SLC19A1 siRNA and miR-497 inhibitors or SEPT2 overexpression vector, the expression of SEPT2 and ERK1/2 phosphorylation levels showed no significant changes. Similar results were obtained with co-transfection of miR-497 mimics and the SEPT2 overexpression vector. Therefore, cancer cells can regulate the expression of SEPT2 through miR-497 by secreting EVs with high expression of circ_SLC19A1, thus affecting the activation of the downstream ERK1/2 pathway and ultimately regulating PCa cell growth and invasion. Therefore, EV-derived circ_SLC19A1 plays an important regulatory role in PCa and may be an important target for PCa prevention and treatment.

The Patterns of non-Adherence to Anti-Platelet Regimen in Stented Patients (PARIS) thrombotic risk score is a novel score for predicting the risk of coronary thrombotic events after percutaneous coronary intervention (PCI). We assessed the prognostic value of this score for mortality in patients with PCI. In this prospective, observational study, we enrolled 10 724 consecutive patients underwent PCI. The primary end point was all-cause death and the secondary end point was major adverse cardiovascular and cerebrovascular events (MACCE) as a composite of all-cause death, myocardial infarction, revascularization, stent thrombosis, or stroke. Among 9782 patients without in-hospital events, a total of 97 deaths and 1002 MACCE occurred during the 2-year follow-up. The mortality risk of patients in the high-risk group was 2.31 times higher than that in the low-risk group (hazard ratio, 2.31; P = .001). This risk score showed prognostic value in evaluating mortality (area under the receiver operating characteristic curve [AUROC], 0.607; 95% confidence interval [CI], 0.551-0.663) and MACCE (AUROC, 0.544; 95% CI, 0.526-0.563; both P < .001). The prognostic value of mortality was higher than that of MACCE (Z = 2.09, P = .04). The PARIS thrombotic risk score shows modest prognostic value for mortality and MACCE, and the prognostic value of mortality is better than that of MACCE.

The present study was aimed at assessing the value of serum NGAL in identifying early acute kidney injury induced by HDMTX. Children aged 1–14 years with newly diagnosed ALL receiving MTX over 3 g/m2 were enrolled. Serum NGAL concentrations, serum creatinine (Scr) and MTX concentrations were measured. The area under the receiver-operating characteristic curve (ROC) was used for evaluating variables’ ability of early diagnosis of AKI. A total of 196 courses of 62 patients were assessed, and 22 courses (11.2%) developed AKI. Twenty-four hours serum NGAL concentrations, 24 h Scr ratio, 48 h Scr ratio, CMTX24 h, CMTX48 h, CMTX72 h were significantly higher in patients with AKI. The combination of 24 h Scr ratio and 24 h serum NGAL had higher value for detecting HDMTX induced AKI compared with the 24 h Scr ratio. And the combination had similar value for detecting HDMTX induced AKI compared with the 48 h Scr ratio. After 48 h, CMTX48 h had a satisfying accuracy in predicting AKI. The proportion of post-HDMTX sepsis in patients with AKI was significantly higher than that in patients without AKI. Serum NGAL levels could be used as a marker in identifying the direct kidney tubular damage induced by HDMTX. The combination of 24 h Scr ratio and 24 h serum NGAL had higher value for early diagnosis of HDMTX associated AKI compared with the 24 h Scr ratio.

Denervation caused by sciatic nerve injury has brought great harm to the patients, especially denervation-induced muscle atrophy. The body stress produces a large number of Schwann cells when the sciatic nerve is injured, and the cells secrete some cytokines including ciliary neurotrophic factor (CNTF) that not only play a role in promoting the repair of sciatic nerve, but also maintain the normal physiological function of the muscles surrounding the damaged nerves. CNTF upregulates janus kinase 2 (JAK2) and signal transducers and activators of transcription 3 (STAT3) signals in myoblasts, and consequently accelerates the proliferation and differentiation of myoblasts. This effect on myoblasts is the most effective way to relieve muscle atrophy. Therefore, increasing CNTF is a promising direction to improve muscle atrophy. In the present study, an oleanolic acid derivative, HA-19, increased the proliferation of Schwann cells, and elevated CNTF production of the cells. HA-19 up-regulated the phosphorylation of JAK2 and STAT3 not only by directly acting on myoblasts, but also by increasing the secretion of CNTF of Schwann cells; and consequently, promoted the proliferation and differentiation of myoblasts. In denervation-induced muscle atrophy mice model, treatment with HA-19 significantly increased the weights of tibialis anterior (TA), gastrocnemius (Gastroc.), extensor digitorum longus (EDL), soleus and quadriceps (Quad.) under atrophied state. And, very interestingly, these muscles under normal condition were also strengthened by HA-19. Our finding demonstrated that HA-19 has a great potential as a lead compound for the drug discovery of anti-denervation-induced muscle atrophy.

We show that a suitable combination of flat-band ferromagnetism, geometry and nontrivial electronic band topology can give rise to itinerant topological magnons. An SU(2) symmetric topological Hubbard model with nearly flat electronic bands, on a Kagome lattice, is considered as the prototype. This model exhibits ferromagnetic order when the lowest electronic band is half-filled. Using the numerical exact diagonalization method with a projection onto this nearly flat band, we can obtain the magnonic spectra. In the flat-band limit, the spectra exhibit distinct dispersions with Dirac points, similar to those of free electrons with isotropic hoppings, or a local spin magnet with pure ferromagnetic Heisenberg exchanges on the same geometry. Significantly, the non-flatness of the electronic band may induce a topological gap at the Dirac points, leading to a magnonic band with a nonzero Chern number. More intriguingly, this magnonic Chern number changes its sign when the topological index of the electronic band is reversed, suggesting that the nontrivial topology of the magnonic band is related to its underlying electronic band. Our work suggests interesting directions for the further exploration of, and searches for, itinerant topological magnons.

Background and Aim: Chronic atrophic gastritis is a known precancerous lesion for gastric cancer, with an overall 5-year survival less than 20%. However, there is few new data describing the progression rate from atrophic gastritis (AG) to gastric cancer in China. We retrospectively analyzed the risk of gastric cancer among patients with AG and aimed to determine the accuracy of endoscopy diagnosis of AG in China. Methods: Clinical features and endoscopic profiles of chronic atrophic gastritis patients from Wenzhou People’s Hospital between January 2006 and December 2016 were analyzed retrospectively. Results: There were 61,810 cases analyzed retrospectively. 3641 cases of atopic gastritis were diagnosed by endoscopy, in which 1704 cases were confirmed by pathological biopsy; the diagnostic coincidence rate was 46.80%; 2631 cases were diagnosed as atrophic gastritis by pathological biopsy, in which 927 cases were ignored by endoscopy; the miss diagnosis rate was 35.23%. The progression rate from chronic atrophic gastritis and non-atrophic gastritis to gastric cancer respectively was 0.79% and 0.43%. The rate of intestinal metaplasia in mild AG, moderate AG and severe AG respectively was 75.63%, 86.18% and 90.32%, 3.42%, 6.27% and 5.16% about dysplasia in three different degree atrophic gastritis. Conclusions: Endoscopy diagnosis and pathology diagnosis of AG were statistically different. Patients with atrophic gastritis have higher risk of developing into gastric cancer, but it needs further investigation. Different degrees of atrophic gastritis have the different proportions of intestinal metaplasia and dysplasia.

Lymphangiogenesis plays an important role in cancer metastasis. Bone marrow-derived mesenchymal stem cells (BMMSCs) migrate to the site of tumorigenesis and in turn promote the metastasis. However, whether BMMSCs involve in the lymphangiogenesis of lung cancer is unclear. Jinfukang has clinically been used for the treatment of non small cell lung cancer (NSCLC) in China. In this study, to investigate the involvement of BMMSCs in lymphangiogenesis in lung cancer, and evaluate the inhibitory effect of Jinfukang on the lymphangiogenesis, chimeric mice were prepared by transplanting bone marrow from green fluorescent protein (GFP) transgenic mice (C57BL/6-EGFP) into irradiated C57BL/6 mice. Then, the chimeric mice were injected subcutaneously with freshly prepared Lewis lung carcinoma cell suspension to make lung tumor model, and the model mice were further orally administrated with Jinfukang once per day for 3 weeks. Four weeks after the bone marrow transplantation, GFP-positive cells primarily existed in bone marrow of acceptor mice, and three more weeks after, Lewis lung carcinoma cells formed a tumor mass in chimeric mice. Observation of GFP-positive cells revealed that BMMSCs transferred into the lung tumor. Immunofluorescent analyses of lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), a lymphatic endothelium marker, demonstrated a part of lymphatic endothelial cells in lung cancer were derived from BMMSCs, and those lymphatic endothelial cells contributed to the lung tumor lymphangiogenesis. Furthermore, Jinfukang treatment resulted in a significant reduction of the average weight of the tumor mass in chimeric mice, and displayed a significant lower number of LYVE-1 positive cells. The present results suggest that BMMSCs transfer to tumor, differentiate into lymphatic endothelial cells, and involve in the lymphangiogenesis in lung cancer of mice. Jinfukang inhibits the lung tumor mass via suppression of the BMMSCs transformation and lung tumor lymphangiogenesis. Our findings might provide the potential for the cancer therapies.

The Al-doped Mg2Si thin films were fabricated by two-target alternative magnetron sputtering technique, and the influences of different Al doping contents on the thermoelectric properties of Al-doped Mg2Si thin films were investigated. The compositions, crystal structures, electronic transport properties and thermoelectric properties of the thin films were examined using energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Hall coefficient measurement and Seebeck coefficient measurement system, respectively. The EDS results show that the thin films doped with Al target sputtering power of 30 W, 60 W and 90 W have the Al content of 0.68 at.%, 1.56 at.% and 2.85 at.%, respectively. XRD results indicate that the diffraction peaks of Mg2Si become stronger with increasing Al dopant. The results of Hall coefficient measurement and Seebeck coefficient measurement system reveal that all the samples are n-type. The conductivities of Al-doped Mg2Si thin films are significantly greater than that of undoped Mg2Si thin film, and increase with increasing Al doping content. With the increase of temperature, the absolute value of the Seebeck coefficients of Mg2Si base thin films increase firstly and then decrease. The maximum power factor obtained is 3.8 mW m−1 k−2 for 1.56 at.% Al-doped Mg2Si thin film at 573 K.

PPARγ has emerged as a master regulator of macrophage polarization and is the molecular target of the thiazolidinedione drugs. Here we show that apigenin binds and activates PPARγ by acting as a modulator. Activation of PPARγ by apigenin blocks p65 translocation into nuclei through inhibition of p65/PPARγ complex translocation into nuclei, thereby decreasing NF-κB activation and favoringM2 macrophage polarization. In HFD and ob/ob mice, apigenin significantly reverses M1 macrophage into M2 and reduces the infiltration of inflammatory cells in liver and adipose tissues, as well as decreases the levels of pro-inflammatory cytokines, thereby alleviating inflammation. Strikingly, apigenin reduces liver and muscular steatosis, decreases the levels of ALT, AST, TC and TG, improving glucose resistance obviously. Unlike rosiglitazone, apigenin does not cause significant weight gain, osteoporosis et al. Our findings identify apigenin as a modulator of PPARγ and a potential lead compound for treatment of metabolic disorders., Graphical Abstract Image 1, Highlights • Apigenin binds and activates PPARγ and significantly reverses the polarization of macrophages from M1 to M2 phenotype. • Activation of PPARγ by apigenin blocks p65 translocation through inhibiting p65/PPARγ complex translocation into nucleus. • Apigenin significantly attenuates metabolic inflammation and disorders without causing some side effects as TZD drugs do. PPARγ is the molecular target of the thiazolidinedione drugs to treat type II diabetes. However, TZD drugs have some side effects including cardiovascular failure, liver toxicity, bone fractures and potential carcinogenesis, which have greatly limited their clinical use. Here, we find apigenin, a flavonoid molecule abundant in various fruits and vegetables, can control macrophage fate to inhibit inflammation and metabolic syndrome without causing some side effects as TZD drugs. Further study indicates that apigenin can target PPARγ with a range of beneficial effects and may represent a lead compound for developing new therapies against metabolic disorders.

A set of Sm-Fe-B films with different compressive stresses were prepared on substrates with different prestrains by ion beam spurting deposition (IBSD). The influence of compressive stress on the magnetic anisotropy and the magnetostriction in sputter-deposited amorphous Sm-Fe-B films were investigated. Films affected by compressive stress all show in-plane anisotropy and easy axis along the direction of stress is induced in the film with compressive stress increasing. Magnetostriction of Sm-Fe-B films affected by compressive stress is improved in low magnetic field while saturation of magnetostriction decreases slightly. At the same time, the magnetostriction rises rapidly in low field measured in a field parallel to the film plane at room temperature with the growth of compressive stress. It is also found that the magnetic domain component which is perpendicular to the film plane increases on a small scale, though the magnetic domain or the magnetic domain component parallel to film plane still exist dominantly.

Muscle atrophy refers to a decrease in the size of muscles in the body, occurs in certain muscles with inactivity in many diseases and lacks effective therapies up to date. Natural products still play an important role in drug discovery. In the present study, derivatives of a natural product, oleanolic acid, were screened with myoblast differentiation and myotube atrophy assays, respectively. Results revealed that one of the derivatives, HA-19 showed the most potent anti-muscle atrophy activity, and was used for further studies. We demonstrated that HA-19 led to the increase of the protein synthesis by activating mechanistic target of rapamycin complex 1 (mTORC1)/p70 S6K pathways, and also enhanced myoblast proliferation and terminal differentiation via up-regulating of the myogenic transcription factors Pax7, MyoD and Myogenin. The interesting thing was that HA-19 also suppressed protein degradation to prevent myotube atrophy by down-regulating negative growth factors, FoxO1, MuRF1 and Atrogin-1. The results were also supported by puromycin labelling and protein ubiquitination assays. These data revealed that HA-19 possessed a "dual effect" on inhibition of muscle atrophy. In disuse-induced muscle atrophy mice model, HA-19 treatment significantly increased the weights of bilateral tibialis anterior (TA), gastrocnemius (Gastroc.), quadriceps (Quad.), suggesting the effectiveness of HA-19 to remit disuse-induced muscle atrophy. Our finding demonstrated that HA-19 has a great potential as an inhibitor or lead compound for the anti-muscle atrophy drug discovery.

In condensed matter physics, there is a novel phase termed "quantum spin liquid", in which strong quantum fluctuations prevent the long-range magnetic order from being established, and so the electron spins do not form an ordered pattern but remain "liquid" like even at absolute zero temperature. Such a phase is not involved with any spontaneous symmetry breaking and local order parameter, and to understand it is beyond the conventional phase transition theory. Due to the rich physics and exotic properties of quantum spin liquids, such as the long-range entanglement and fractional quantum excitations, which are believed to hold great potentials in quantum communication and computation, they have been intensively studied since the concept was proposed in 1973 by P. W. Anderson. Currently, experimental identifications of a quantum spin liquid still remain as a great challenge. Here, we highlight some interesting experimental progress that has been made recently. We also discuss some outstanding issues and raise questions that we consider to be important for future research., Comment: A short review paper published in npj Quantum Materials. Due to the limitation on the number of references, we are very unfortunate to miss many excellent ones

Pancreatic cancer is one of the most deadly neoplasm with a 5-year survival rate of less than 6% owing to its remarkable tolerance to nutrient starvation, and new drugs and treatment strategies are urgently needed. During a project aiming at discovery of anticancer agents, we performed a structure modification on polycyclic polyprenylated acylphloroglucinols (PPAPs) skeleton, and discovered that PPAP rearranged to a tetrahydroquinolin-2(1H)-one feature. Here, series of tetrahydroquinolin-2(1H)-one derivatives were designed, synthesized and evaluated against a highly metastatic human pancreatic cancer cell line (PANC-1), and the structure-activity relationship was also discussed. Among them, derivative 11k showed the most potent inhibitory activity with an IC50 value of 4.9 μM under nutrient-deprived condition. In contrast, all these derivatives exhibited low cytotoxicity against PANC-1 cells under normal nutrient condition, suggesting that the derivatives appeared to allow alternative tumor cell death mechanisms, and led to less toxicity. Further evaluations demonstrated that 11k decreased colony formation and induced the apoptosis of PANC-1 under nutrient-deprived condition in a concentration dependent manner. In in vivo study, 11k significantly suppressed the tumor development and weight in nude mice. Preliminary mechanism research revealed that 11k clearly downregulated LC3-II expression and increased the level of p62, two key autophagy markers and critical signals for pancreatic tumor growth and progression. Our current findings demonstrated that 11k might be a promising candidate for the new chemotherapeutic molecule of pancreatic cancer, and deserve further study.

The confinement and deconfinement of spinons in the square-lattice antiferromagnetic ${J}_{1}\ensuremath{-}{J}_{2}$ Heisenberg model are elaborated by exploring the evolution of the whole excitation spectra with ${J}_{2}$, based on the spin cluster perturbation theory. We find that deconfined spin-$1/2$ spinons beyond the conventional spin-1 magnons have already emerged partially even in the limit ${J}_{2}=0$ and develop with ${J}_{2}$, exhibiting as a continuum close to $(\ensuremath{\pi},0)$ in the Brillouin zone. In the region near ${J}_{2}=0.5{J}_{1}$, the entire spectrum is characterized by a broad continuum in which all magnons are deconfined into spinons, whose ground state is attributed to a ${Z}_{2}$ quantum spin liquid with the aid of a variational-Monte-Carlo analysis. The spinon continua are also found in the stripe phase with ${J}_{2}g0.6{J}_{1}$. Our study provides spectroscopic evidences for the fractionalized excitations and quantum spin liquid and highlights the rising field to explore the exotic quantum phases from a perspective of excitation spectrum.

The magnetic properties of 4d and 5d transition-metal insulating compounds with the honeycomb structure are believed to be described by the Heisenberg-Kitaev model, which contains both the isotropic Heisenberg interaction J and anisotropic Kitaev interaction K. In this paper, to investigate the charge dynamics in these materials, we study the single-hole propagation of the t-J-K model in various magnetically ordered phases by the self-consistent Born approximation. We find that there are low-energy coherent quasiparticle (QP) excitations in all of these phases which appear firstly around the K point in the Brillouin zone (BZ), but the band-widths of these QPs are very small due to the hole-magnon coupling. Interestingly, in the zigzag phase relevant to recent experiments, though the QP weights are largely suppressed in the physical spectra in the first BZ, we find that they recover in the extended BZs. Moreover, our results reveal that the low-energy QP spectra are reduced with the increase of K., 9 pages, 5 figures