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Two new β-carboline alkaloids, anemonilins A and B (1–2), and two known β-carboline alkaloids, flazine (3) and 4-(9H-β-carbolin-l-yl)-4-oxo-butyric acid (4), were isolated from the roots of Anemone altaica. The structures of the isolated compounds were elucidated with spectroscopic and spectrometric methods (1D and 2DNMR, HRESIMS). Compounds 2 and 4 significantly attenuated the growth inhibition induced by lipopolysaccharide (LPS) in normal rat kidney tubule epithelioid (NRK52e) cells (p < 0.05 or p < 0.01). Furthermore, compound 2 significantly reduced the apoptosis (p < 0.05) and the caspase-3/9 expression of NRK52e cells induced by LPS. [ABSTRACT FROM AUTHOR]

Whereas ferromagnets have been known and used for millennia, antiferromagnets were only discovered in the 1930s1. At large scale, because of the absence of global magnetization, antiferromagnets may seem to behave like any non-magnetic material. At the microscopic level, however, the opposite alignment of spins forms a rich internal structure. In topological antiferromagnets, this internal structure leads to the possibility that the property known as the Berry phase can acquire distinct spatial textures2,3. Here we study this possibility in an antiferromagnetic axion insulator—even-layered, two-dimensional MnBi2Te4—in which spatial degrees of freedom correspond to different layers. We observe a type of Hall effect—the layer Hall effect—in which electrons from the top and bottom layers spontaneously deflect in opposite directions. Specifically, under zero electric field, even-layered MnBi2Te4 shows no anomalous Hall effect. However, applying an electric field leads to the emergence of a large, layer-polarized anomalous Hall effect of about 0.5e2/h (where e is the electron charge and h is Planck’s constant). This layer Hall effect uncovers an unusual layer-locked Berry curvature, which serves to characterize the axion insulator state. Moreover, we find that the layer-locked Berry curvature can be manipulated by the axion field formed from the dot product of the electric and magnetic field vectors. Our results offer new pathways to detect and manipulate the internal spatial structure of fully compensated topological antiferromagnets4–9. The layer-locked Berry curvature represents a first step towards spatial engineering of the Berry phase through effects such as layer-specific moiré potential.A new type of Hall effect—the layer Hall effect—is produced in a 2D antiferromagnet that does not exhibit any net magnetization. [ABSTRACT FROM AUTHOR]

Poly(N-(3-carboxyphenyl)maleimide-alt-styrene) with superior heat-resistance was synthesized by free radical copolymerization and its structure was confirmed by FTIR and NMR spectroscopy. To show the advantages in heat-resistance of the synthesized copolymers, the thermal properties of poly(N-phenylmaleimide-alt-styrene) and poly(N-phenylmaleimide-alt-maleic anhydride) with similar structures were determined. DSC/TG analysis showed that the synthesized copolymer exhibited the better thermal properties than two other copolymers due to the formation of a chemically crosslinked three-dimensional network during heating. [ABSTRACT FROM AUTHOR]

The cyclic behavior of Q345GJ steel was explored by strain cycle tests, stress cycle tests and uniaxial tension tests. The results of strain cycle tests confirmed that Q345GJ steel has no cyclic hardening, and it had rare strain amplitude effect or strain history effect. The stress cycle tests confirmed that the cumulative plastic strain goes up stably under eccentric stress with increasing loading loops. Thus, it can be concluded that the hardening characteristics of Q345GJ coincide with kinematic hardening, having almost no isotropic hardening. The superposition of four nonlinear kinematic hardening model based on Chaboche's constitutive model was used to predict the hardening characteristics of Q345GJ steel, and the parameters of the constitutive model were calibrated based on the test results. The numerical validation of the constitutive model confirmed that the proposed parameters can give good simulation for strain cycle behavior and stress cycle behavior of Q345GJ steel. [ABSTRACT FROM AUTHOR]

Blue emitting phosphor SrZn(PO):Eu is synthesized by a high temperature solid state method, and the luminescent properties are investigated. At the 330 nm radiation excitation, SrZn(PO):Eu presents an emission band at 416 nm, which is assigned to the 4f5d→4f transition of Eu ion. The concentration quenching effect of Eu in SrZn(PO) has been validated and proved to be a resonant type via a dipole-dipole interaction. The critical distance ( R) of Eu in SrZn(PO) is calculated to be 3.244 nm. The Commission International de I'Eclairage (CIE) chromaticity coordinates of SrZn(PO):Eu locate at the blue region, such as (0.150, 0.072). The results indicate that the SrZn(PO):Eu phosphor may have potential applications in white light emitting diodes (LEDs). [ABSTRACT FROM AUTHOR]

SrZn(PO):Sm phosphor was synthesized by a high temperature solid-state reaction in atmosphere. SrZn(PO):Sm phosphor is efficiently excited by ultraviolet (UV) and blue light, and the emission peaks are assigned to the transitions of G-H (563 nm), G-H (597 nm and 605 nm) and G-H (644 nm and 653 nm). The emission intensities of SrZn(PO):Sm are influenced by Sm concentration, and the concentration quenching effect of SrZn(PO):Sm is also observed. When doping A ( A=Li, Na and K) ions, the emission intensity of SrZn(PO):Sm can be obviously enhanced. The Commission Internationale de l'Eclairage (CIE) color coordinates of SrZn(PO):Sm locate in the orange-red region. The results indicate that the phosphor has a potential application in white light emitting diodes (LEDs). [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Abnormal expression of microRNAs (miRNAs) contributes to glioma initiation. However, the expression of miRNAs in tumour tissue or blood of spinal cord glioma (SCG) patients, particularly in high-grade spinal gliomas (Grade IV) known as glioblastoma (GBM), remains largely unknown. In this study we aimed to determine differentially expressed miRNAs (DEmiRNAs) in the tissue and blood between spinal cord glioblastoma (SC-GBM) patients and low grade SCG (L-SCG) patients. Additionally, we predicted key miRNA targets and pathways that may be critical in glioma development using pathway and gene ontology analysis. A total of 74 miRNAs were determined to be differentially expressed (25 upregulated and 49 downregulated) in blood, while 207 miRNAs (20 up-regulated and 187 down-regulated) were identified in tissue samples. Gene ontology analysis revealed multicellular organism development and positive regulation of macromolecule metabolic process to be primarily involved. Pathway analysis revealed "Glioma", "Signalling pathways regulating pluripotency of stem cells" to be the most relevant pathways. miRNA-mRNA analysis revealed that hsa-miRNA3196, hsa-miR-27a-3p, and hsa-miR-3664-3p and their target genes are involved in cancer progression. Our study provides a molecular basis for SCG pathological grading based on differential miRNA expression. [ABSTRACT FROM AUTHOR]