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To improve the understanding of the near-field soil and topographic amplification effects, an analytical solution by the authors for the scattering of plane SH waves by a radially inhomogeneous semi-cylindrical valley is extended to the case of a line source of cylindrical SH waves. Upon confirmation of its accuracy with past exact solutions for a homogeneous and an inhomogeneous semi-cylindrical valley under far-field plane SH waves, the extended solution is used to calculate the ground motion amplification factors for both the homogeneous and inhomogeneous valleys subjected to near-field waves. A comprehensive parametric study is conducted with respect to the location of the wave source, the dimensionless frequency of the incident waves, and the inhomogeneity degree of the covering soil layer. It is found that more amplifications and reductions of ground motions will occur within a certain range in and around the valley as the sources are located further. Consistent with the far-field case, it is confirmed that an increase of the degree of inhomogeneity of the covering soil layer generally amplifies the ground motions significantly. [ABSTRACT FROM AUTHOR]

A new Al/NiSiO2 (M)/NiSiO2 (D)/SiO2 solar selective absorbing coating were carried out by combining experiments with optical simulation. A series of NiSiO2 single layers were deposited by using magnetron reactive sputtering method with different O2 gas flowing rates, and the solar absorbing coating was designed and optimized by using optical software. The result indicates that the coating deposited on the stain steel substrate exhibits high absorptance (0.933) and low emittance (0.14) at 400 °C. The coating exhibits good thermal stability after aging at 450 °C for 100 h in air. After aging at 450 °C in air for 100 h, the ratio of absorptance and emittance (α/ε) of the coating increases from 6.66 to 7.62, the result shows that the coating has good thermal stability. [ABSTRACT FROM AUTHOR]

Abstract: The effects of digestion in vitro on the flavonoid content and antioxidant activities of aged and fresh dried tangerine peel were investigated by treating with simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) compared with organic solvent or deionized water. The total phenolic content of both aged and fresh dried tangerine peel were significantly decreased by SGF and SIF treatments, with the exception of the SIF‐treated fresh dried peel. The total flavonoid content of both the aged and fresh dried tangerine peel were also reduced by SGF, but not by SIF, compared with deionized water. FRAP values were markedly improved by SGF and reduced by SIF treatments compared with deionized water. Conversely, the ABTS value of SIF‐treated fresh dried peel was significantly higher than that of SGF‐treated peel. The antioxidant activities of tangerine peel were altered by simulated digestion in vitro. Practical applications: Citrus peel is the main byproduct of the citrus industry. Tangerine is one of the most important citrus widely planted in Southeast Asia. Dried tangerine peel which called “Chenpi” in Chinese traditional medicine was used for indigestion and inflammatory treatments. Dried tangerine peel can be developed as functional foods. To investigate the simulated gastric and intestinal fluid digestion on the contents of active component and antioxidant activities of aged dried tangerine peel and fresh dried tangerine peel could provide a theoretical basis for the commercial development and utilization of dried tangerine peel. [ABSTRACT FROM AUTHOR]

A deep learning method consisting of the gated recurrent (GRU) neural network is proposed to predict the seismic responses of underground structures in single-layered soil and multi-layered soil. The proposed neural network employed ground motion as the input, and the acceleration time history of underground structure acquired by a finite element method (FEM) to be the output. The distribution of the normalized errors and the error of the peak value of the predicted acceleration time history are adopted to evaluate the prediction performance and extrapolating ability of the proposed GRU architecture. The GRU network showed better prediction performance in the seismic response of a tunnel in a homogeneous sand layer than in a clay layer, as sand has a higher shear modulus representing lower nonlinearity of the soil-structure system. The peak acceleration of a two-story three-span subway station in multi-layered soil exhibited similar prediction accuracy to the tunnel in single-layered clay. The proposed GRU neural network generally displayed satisfactory prediction performances on the acceleration responses of underground structures in various soil conditions. • Proposes a GRU-based model to predict seismic response of underground structures. • Model employes ground motion as input. • Exhibits better seismic response of tunnel in sand than in clay layer. • Obtains well acceleration responses of subway station in multi-layered soil. [ABSTRACT FROM AUTHOR]

Background: Prostate cancer is a leading cause of cancer-related deaths among men worldwide. Docetaxel chemotherapy has proven effective in improving overall survival in patients with castration-resistant prostate cancer (CRPC), but drug resistance remains a considerable clinical challenge. Methods: We explored the role of Ribonucleotide reductase subunit M2 (RRM2), a gene associated with senescence, in the sensitivity of prostate cancer to docetaxel. We evaluated the RRM2 expression, docetaxel resistance, and ANXA1 expression in prostate cancer cell lines and tumour xenografts models. In addition, We assessed the impact of RRM2 knockdown, ANXA1 over-expression, and PI3K/AKT pathway inhibition on the sensitivity of prostate cancer cells to docetaxel. Furthermore, we assessed the sensitivity of prostate cancer cells to the combination treatment of COH29 and docetaxel. Results: Our results demonstrated a positive association between RRM2 expression and docetaxel resistance in prostate cancer cell lines and tumor xenograft models. Knockdown of RRM2 increased the sensitivity of prostate cancer cells to docetaxel, suggesting its role in mediating resistance. Furthermore, we observed that RRM2 stabilizes the expression of ANXA1, which in turn activates the PI3K/AKT pathway and contributes to docetaxel resistance. Importantly, we found that the combination treatment of COH29 and docetaxel resulted in a synergistic effect, further augmenting the sensitivity of prostate cancer cells to docetaxel. Conclusion: Our findings suggest that RRM2 regulates docetaxel resistance in prostate cancer by stabilizing ANXA1-mediated activation of the PI3K/AKT pathway. Targeting RRM2 or ANXA1 may offer a promising therapeutic strategy to overcome docetaxel resistance in prostate cancer. [ABSTRACT FROM AUTHOR]

The dimension reduction spectral representation method (SRM) is generally employed with the generalized probability density evolution method (GPDEM) to implement the seismic reliability assessment, where a noticeable non-zero value in the mean value of ground motion would be obtained. This study proposed an updated spectral representation method (U-SRM) to improve the simulated mean values, which coupled with GPDEM to investigate the nonlinear responses and seismic reliability assessment of a tunnel. Results obtained from the numerical study were compared between SRM and U-SRM. The horizontal displacement at the tunnel crown is more conservative using U-SRM than SRM in the reliability assessment of tunnels. Results indicated that U-SRM coupled with GPDEM is an efficient method to analyze the nonlinear responses and the seismic reliability of tunnels, and could serve as a reference for tunnel design in seismically active zones. • An updated dimensional reduction spectral representation method is proposed. • U-SRM coupled with GPDEM is an efficient method to do the seismic reliability of tunnels. • The horizontal displacement at the tunnel crown is more conservative using U-SRM than SRM. [ABSTRACT FROM AUTHOR]

The dynamic response of a double-beam system under the moving oscillator is investigated. The double-beam system is made of two elastic homogeneous isotropic Euler-Bernoulli beams, which are identical, parallel with each other and supported continuously by a foundation of elastic springs provided with viscous damping. The moving oscillator is simplified by the single degree of freedom (SDoF) system. The coupled equations governing the vibration of beams are decoupled by a simple change. Then a state-space equation governing the vibration of both beams and the moving oscillator is established by introducing some state variables, and solved by a single-step scheme. Numerical examples are employed to investigate the effects on the response of some important parameters, such as initial condition of the oscillator, and the mechanical properties of the oscillator and foundation. Some interesting tendencies in the response of beams and oscillator are highlighted. [ABSTRACT FROM AUTHOR]

Primary sarcopenia is a multicausal skeletal muscle disease associated with muscle strength and mass loss. Skeletal muscle fibrosis is one of the significant pathological manifestations associated with the development of age-related sarcopenia. Irisin, which is cleaved by the extracellular domain of fibronectin type Ⅲ domain-containing protein 5 (FNDC5), has previously been reported to exert antifibrotic effects on the heart, liver, and pancreas, but whether it can rescue skeletal muscle fibrosis remains unknown. In this study, we examined the effects of irisin on D-galactose (D-gal)-induced skeletal muscle fibroblasts. We found that D-gal-induced senescence, fibrosis, and redox imbalance were inhibited by irisin treatment. Mechanistically, irisin or FNDC5 overexpression attenuated D-gal-induced senescence, redox imbalance, and fibrosis by regulating the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway. Overall, irisin might be a promising therapeutic candidate for age-related skeletal muscle fibrosis. • Irisin reduced redox imbalance and senescence. • Irisin attenuated skeletal muscle fibrosis. • Irisin exerted effects by activating the PI3K/Akt pathway. [ABSTRACT FROM AUTHOR]

Adsorbed gas, the presence of which is a significant difference between the shale gas and conventional gases, has attracted considerable attention, particularly in China. A series of shale gas adsorption isotherms were measured at 30 °C and at pressures up to 10.94 MPa for the lower Silurian marine shale of the Longmaxi Formation collected in southeastern Chongqing, China. The maximum adsorbed gas content was 0.72–3.89 m 3 /t. Using measurements of the total organic carbon (TOC), thermal maturity, X-ray diffraction and low-pressure nitrogen adsorption, the basic characteristics of the shale reservoir were analyzed. The Ono–Kondo model was used to fit the measured methane adsorption isotherms with correlation coefficients as high as 0.9896–0.9976. The model characterized the filling adsorption features of nanopores under supercritical conditions. Monolayer saturated adsorption is generally less than the maximum adsorption, suggesting that as pressure increases, methane adsorption tends to become a multilayer adsorption. Among the geological parameters, TOC displayed a strong positive correlation with shale gas adsorption capacity. No obvious relation between the shale gas adsorption capacity and the clay was observed, indicating that organic matter has more significant contribution to shale gas adsorption than clay. The adsorption capacity significantly increased linearly with increasing total surface area, suggesting significant effects of pore structure on the shale gas storage. On the basis of the pressure sensitivity of adsorption rate, the adsorption process was divided into three stages: (1) an initial low-pressure stage, (2) an intermediate-pressure stage, and (3) a high-pressure stage. The third stage displayed methane desorption at high pressure. The similarities and differences of the Langmuir model and the Ono–Kondo model were assessed. An evaluation of which model is more accurate is difficult because both models can show good fits to experimental data. However, considering the methane adsorption mechanism, the Ono–Kondo model appears to be more reliable in describing the process of methane adsorption in shale because it predicts a more reasonable supercritical adsorption and can reflect the adsorption transformation from monolayer to multiple layers. [ABSTRACT FROM AUTHOR]

This paper deals with the asymptotic stabilization of a class of port-Hamiltonian (pH) 1-D Partial Differential Equations (PDE) with spatial varying parameters, interconnected with a class of linear Ordinary Differential Equations (ODE), with control input on the ODE. The class of considered ODE contains the effect of a proportional term, that can be considered as the proportional action of a controller or a spring in case of mechanical systems. In this particular case of study, it is not possible to directly add damping on the boundary of the PDE. To remedy this problem we propose a control law that makes use of a "strong feedback" term. We first prove that the closed-loop operator generates a contraction strongly continuous semigroup, then we address the asymptotic stability making use of a Lyapunov argument, taking advantage of the pH structure of the original system to be controlled. Furthermore, we apply the proposed control law for the stabilization of a vibrating string with a tip mass and we show the simulation results compared with the application of a simple PD controller. [ABSTRACT FROM AUTHOR]

This brief considers the control design of a nonlinear distributed parameter system in infinite dimension, described by the hyperbolic partial differential equations of de Saint-Venant. The nonlinear system dynamic is formulated by a multimodels approach over a wide operating range, where each local model is defined around a set of operating regimes. A new proportional integral feedback is designed and performed through bilinear operator inequality and linear operator inequality techniques for infinite dimensional systems. The new results have been simulated and also compared with previous results in finite and infinite dimension, to illustrate the new theoretical contribution. [ABSTRACT FROM PUBLISHER]

The spectral representation method (SRM) is widely used when simulating spatially variable ground motions. It has mainly two formulas, i.e., the random amplitudes and the random phases formulas. There exist three methods for decomposing the cross spectral density matrix: Cholesky decomposition, eigen decomposition, and root decomposition. Therefore, there are six forms with respect to the different combinations of the simulation formulas and the decomposition methods. To provide researchers and engineers with the guidance on choosing simulation method, the six forms are systematically investigated from five aspects: the power intensity, response spectra, and stochastic error of auto/cross spectral density, Fourier spectra, and difference indexes for Fourier amplitudes and phases. Finally, we give the following advice: the characteristics of the ground motions simulated by the random amplitudes formula are independent of the decomposition method, while the characteristics of the ground motions simulated by random phases formula are dependent of the decomposition method. Furthermore, the root decomposition is strongly recommended when utilizing the random phases formula. [ABSTRACT FROM PUBLISHER]

Correction to: Bulletin of Engineering Geology and the Environment (2021) https://doi.org/10.... In the online published article, there are the following errors. The symbols on the left hand side of the Equations 4 and 9 should be in Italics. The symbol ' needs to be replaced by the symbol ' wherever (i.e. in equations and in the text) it appears. [Extracted from the article]