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Abstract Atopic dermatitis (AD) is a common inflammatory skin disease. Matrine is the main component of the traditional Chinese medicine Sophora flavescens, and it poses good therapeutic effects on inflammatory diseases. This study aimed to explore the pharmacological effects of matrine on AD and its underlying mechanism. An AD mouse model and inflamed human epidermal keratinocyte cells (HaCaT) cells were established. Histopathological aspects were examined using hematoxylin and eosin staining, toluidine blue staining, and immunohistochemistry. The mRNA and protein expressions were assessed using quantitative real‐time polymerase chain reaction and Western blot, respectively. The secretions of cytokines and chemokines were examined by enzyme‐linked immunosorbent assay. Flow cytometry was carried out to analyze the proportions of T‐helper (Th) 1 and Th2 cells. Herein, our results displayed that matrine diminished AD symptoms and decreased heat shock protein 90 (Hsp90) expression. Matrine decreased the Th2 cytokine levels in the ear tissues and serum, and it also significantly repressed inflammatory cytokines (thymus activation regulated chemokine and interleukin‐6) secretions by repressing the Hsp90/NF‐κB signaling axis in inflamed HaCaT cells. Furthermore, matrine inhibited Th2 differentiation of CD4+ T cells when co‐cultured with inflamed HaCaT cells. Matrine can regulate the Th1/Th2 inflammatory response by inhibiting the Hsp90/NF‐κB signaling axis to alleviate AD. Therefore, it may be a candidate for AD treatment.

We demonstrate how magnon Kerr nonlinearity creates bistability of quantum states when the magnon mode is strongly driven by a microwave field in a nonlinear cavity magnonic system. Numerical simulation results with experimentally feasible parameters show that the method where the system is driven far from equilibrium is a reliable way to achieve squeezed states for magnons and photons and to carry out magnon-photon entanglement, revealing mysterious phenomena of bistability. In addition, the Kittel mode can jump from one state to another one near two switching points, thus achieving the hysteresis loop phenomenon. Our results indicate that bistable quantum states could provide a way to study macroscopic quantum bistable phenomena in nonlinear systems and also can be found in broad applications in magnetic spintronics.

The effect of Sr and cooling rate on the microstructure of Al-2.5%Mn alloy was studied by OM, SEM and XRD. The results showed that Sr not only refined the primary phase, but also refined eutectic microstructures. However, there was obvious delamination in the alloy. When the content of Sr was 0.2%–0.65%, the primary phase in the upper part of alloy changed from coarse needle and lath-shaped to fine block and needle-like. With the Sr content increased, the needle-like structure in the alloy tended to be more and longer, but the size of α -Al tended to be finer. At the bottom, there were many large massive phases, which were much more refined than the primary phase without Sr With the cooling rate increased, the primary phase was refined greatly and almost all of them transformed into eutectic microstructure. Besides, the delamination of microstructure disappeared.

Boundary effect and the noise robustness are the two crucial aspects which affect the effectiveness of the damage localization based on the mode shape measurements. To overcome the boundary effect problem and enhance the noise robustness in damage detection, a simple damage localization method is proposed based on the Singular Value Decomposition (SVD) for the mode shape of composite plates. In the proposed method, the boundary effect problem is addressed by the decomposition and reconstruction of mode shape, and the noise robustness in enhanced by the noise filtering during the decomposition and reconstruction process. Numerical validations are performed on plate-like structures for various damage and boundary scenarios. Validations show that the proposed method is accurate and effective in the damage detection for the two-dimensional structures. [ABSTRACT FROM AUTHOR]

The most common and effective way of rotating machinery diagnostics is to extract fault impact features from the vibration signals and to carry out further processing. As for planetary gear sets, because of the simultaneous mesh of multiple gears and the effect of the carrier rotation, the fault features are submerged in the strong harmonic signals and other noise. Due to the lack of prior information on the faults, the conventional fault diagnostic methods often fail to achieve satisfactory results. To address this problem, we give the prior information of a chipped planetary gear set by dynamics simulation, and utilize the information in the time domain to improve the diagnosis performance. Firstly, a pure torsional lumped parameter model is used to simulate the system vibration response with different degrees of failure. Through statistical analysis, the margin factor, the most sensitive indicator, is selected as prior information to reflect the local gear fault among several indexes. Finally, a weighted sparse representation method based on the prior information provided above is proposed to extract the impact features. Moreover, it is found that the extracted components have a strong–weak cyclic impact feature in the chipped planetary gear sets. The features and effectiveness of the method are verified by an experiment on a planetary gearbox test rig. To validate the superiority of the proposed method, comparisons are made among several state-of-the-art feature extraction methods. [ABSTRACT FROM AUTHOR]