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High-fat diet (HFD)-induced obesity leads endothelial dysfunction and contributes to cardiovascular diseases. Palmitic acid (PA), a free fatty acid, is the main component of dietary saturated fat. Physcion, a chemical ingredient from Rhubarb, has been shown anti-hypertensive, anti-bacteria, and anti-tumor properties. However, the effects of physcion on endothelial dysfunction under HFD-induced obesity have not been reported. The purpose of the present study was to define the protective effect of physcion on HFD-induced endothelial dysfunction and its mechanisms involved. Obesity rat model was induced by HFD for 12 weeks. A rat thoracic aortic ring model was used to investigate the effects of physcion on HFD-induced impairment of vasorelaxation. Endothelial cell injury model was constructed in human umbilical vein endothelial cells (HUVECs) by treating with PA (0.25 mM) for 24 h. The results revealed that physcion reduced body weight and the levels of plasma TG, prevented impairment of endothelium-dependent relaxation in HFD-fed rats. In PA-injured HUVECs, physcion inhibited impaired viability, apoptosis and inflammation. Physcion also suppressed PA-induced both oxidative stress and ER stress in HUVECs. Furthermore, physcion increased PA-induced decrease in the activation of eNOS/Nrf2 signaling in HUVECs. These findings suggest that physcion has a significant beneficial effect on regulating HFD-induced endothelial dysfunction, which may be related to the inhibition of oxidative stress and ER stress through activation of eNOS/Nrf2 signaling pathway. [Display omitted] • Physion inhibits HFD-induced endothelial dysfunction in rats. • Physion attenuates PA-induced endothelial cell apoptosis and inflammation. • eNOS/Nrf2 signaling involves in protection of physion. [ABSTRACT FROM AUTHOR]

In this work, CMAS corrosion behavior of hot-pressed (Y 1- x Yb x) 2 SiO 5 ceramics at 1573 K within 32 h has been investigated. The corrosion products contain non-stoichiometric apatite and garnet, which form according to the dissolution-reprecipitation mechanism. With abundant calcia-magnesia-aluminosilicate, the growth rate of apatite layer increases rapidly with prolonging corrosion time, which results in the rapid corrosion especially after 4 h. Furthermore, the measured thickness of apatite layer in (Y 1- x Yb x) 2 SiO 5 is much lower than the predicted value based on the optical basicity (OB) theory. This work provides a new insight of solid-solutionizing strategy in the resistance of rare-earth monosilicate to CMAS corrosion. • The producing conditions of two different CMAS corrosion products are revealed. • The variation on the growth rate of apatite layer over corrosion time is discussed. • The apatite layer thickness is smaller than the predicted value based on OB theory. [ABSTRACT FROM AUTHOR]

Calcia-magnesia-aluminosilicate (CMAS) corrosion behaviors of hot-pressed (Y 1- x Yb x) 2 SiO 5 ceramics at 1673 K and 1773 K have been investigated. The main corrosion product of nonstoichiometric Ca-RE-Si-O apatite phase evolves with increasing temperature or prolonging corrosion time. The growth of apatite layer at 1673 K follows approximately a linear rate law, however it follows a proximately parabolic rate law at 1773 K. The growth rate of the apatite layer at 1773 K is lower than that at 1673 K in the process of interaction between CMAS and rare-earth monosilicates. Yb-doping mediates the CMAS corrosion resistance of Y 2 SiO 5 effectively by changing the growth rate of apatite layer and the composition of formed apatite phase. This work provides new insights on compositional regulation of (Y 1- x Yb x) 2 SiO 5 EBCs materials to resist CMAS corrosion. [ABSTRACT FROM AUTHOR]

The primary objective of this study was to assess the feasibility of utilizing urine-prepared NaOH solution (NUr) as an innovative pretreatment approach for enhancing BHP in rice straw through anaerobic digestion (AD) process. The findings suggest that pretreatment with NUr could substantially enhance hydrolysis rates and H 2 production. The maximum biohydrogen production (BHP) yield reached 184.46 mL/g substrate with 86.98 % holocellulose retention yield and 59.84 % removal of lignin when RS was pretreated by NUr at a concentration of 3 % w/v, 20 % solid loading, −12 °C, and 3 months. Macro and microstructure analysis confirmed more cellulose and hemicellulose were exposed due to the lignin removed, and crystallinity decreased after NUr pretreatment. The energy conversion efficiency (ECE) attained via NUr pretreated RS was 10.38 %, exceeded that of raw RS by 62.19 %. These findings offer a promising and efficient pretreatment technology for enhancing the recovery of H 2 from lignocellulosic biomass, yielding both environmental and economic advantages. [Display omitted] • The maximum bio-H 2 production from RS reached 184.46 mL/g substrate by NUr pretreatment. • NUr pretreatment could achieve 86.98 % holocellulose retention and 59.84 % removal of lignin. • NUr pretreatment improves the biohydrogen potential (B 0) of RS by 91.86 %. • NUr pretreatment improves hydrolysis rate (k) of RS by 37.04 %. • Material balance and ECE analysis suggested NUr is an attractive pretreatment method. [ABSTRACT FROM AUTHOR]

In this paper, a survey of the Nanchang Metro Line 1 is completed to determine the effectiveness of a grout assessment method combines GPR and image processing. Two aspects are used as a basis: one is to estimate the thickness of the grouting layer, and the other is to determine the presence and distribution of any damage. Finite-difference time-domain simulation is used to assist the interpretation of measured data. The results show most grouting layer is approximately 30 cm thick (i.e., the standard 30 cm). Several defects in the grouting layer were also found, primarily voids, crack or fissure. [ABSTRACT FROM AUTHOR]

Four kinds of quinary high-entropy rare-earth (RE) monosilicates and (Y 1- x Yb x) 2 SiO 5 have been synthesized by solid-state reaction method. Selected rare-earth oxides of Lu 2 O 3 to Gd 2 O 3 react with silica to form homogeneous monosilicate solid solutions at a sintering temperature of 1773 K for 4 h. Wherein Gd-Si-O transforms from oxy-apatite type to X2-RE 2 SiO 5 with increasing the synthesis temperature from 1573 K to 1773 K. Increasing the rare-earth ion species changes the distortion degrees of [REO m ] a little bit. However, it's more effective to improve the distortion degrees with only introducing Yb3+ into Y3+ sites of Y 2 SiO 5. Stronger distortion of [REO m ] improves the high-temperature resistance to thermal deformation, resulting in a lower coefficient of thermal expansion (CTE). Due to the highest distortion degree of [REO m ], (Y 0.2 Yb 0.8) 2 SiO 5 exhibits the lowest CTE of 6.78 × 10−6 K−1 at 1473 K. Meanwhile, RE-doping enhances the distortion and phonon scattering, contributing to a lower thermal conductivity. [ABSTRACT FROM AUTHOR]

This work uses in situ transmission electron microscopy (TEM) based micromechanical testing to isolate and quantify the microstructural toughening mechanisms active in nanostructured Al 2 O 3 /GdAlO 3 eutectic samples. The effect of fracture direction across orthogonal sections of the rod-like eutectic was used to reveal the influence of different fracture paths and mechanisms on toughening. The average fracture toughnesses of the rod-like structures in the longitudinal cross-section and transverse cross-section are 2.4 MPa·m1/2 and 2.7 MPa·m1/2, respectively. Multiple samples tested in the longitudinal cross-section show significant R-curve toughening response, and obtain values greatly exceeding the initial values upon crack extension. It is concluded that nanoscale crack bridging induces deflection of the crack path, which leads extrinsic energy dissipation as the crack opens. Micropillar compressions are also performed to investigate the composite's strength. Sample orientation strongly affects the deformation mode and interfacial sliding occurs when the maximal shear stress is parallel to the interface. [ABSTRACT FROM AUTHOR]

Elevated levels of plasma homocysteine (Hcy) causes severe cardiac dysfunction, which is closely associated with oxidative stress. Emodin, a naturally occurring anthraquinone derivative, has been shown to exert antioxidant and anti-apoptosis activities. However, whether emodin could protect against Hcy-induced cardiac dysfunction remains unknown. The current study aimed to investigate the effects of emodin on the Hcy-induced cardiac dysfunction and its molecular mechanisms. Rats were fed a methionine diet to establish the animal model of hyperhomocysteinemia (HHcy). H9C2 cells were incubated with Hcy to induce a cell model of Hcy-injured cardiomyocytes. ELISA, HE staining, carotid artery and left ventricular cannulation, MTT, fluorescence staining, flow cytometry and western blotting were used in this study. Emodin significantly alleviated the structural damage of the myocardium and cardiac dysfunction from HHcy rats. Emodin prevented apoptosis and the collapse of MMP in the Hcy-treated H9C2 cells in vitro. Further, emodin reversed the Hcy-induced apoptosis-related biochemical changes including decreased Bcl-2/Bax protein ratio, and increased protein expression of Caspase-9/3. Moreover, emodin suppressed oxidative stress in Hcy-treated H9C2 cells. Mechanistically, emodin significantly inhibited the Hcy-activated MAPK by reducing ROS generation in H9C2 cells. Furthermore, emodin upregulated NO production by promoting the protein phosphorylation of Akt and eNOS in injured cells. The present study shows that emodin protects against Hcy-induced cardiac dysfunction by inhibiting oxidative stress via MAPK and Akt/eNOS/NO signaling pathways. [Display omitted] • Emodin prevents homocysteine-induced cardiac dysfunction in rats. • Emodin inhibits homocysteine-induced cardiomyocyte apoptosis. • Emodin attenuates homocysteine-activated MAPK signaling by suppressing ROS production in cardiomyocyte. • Activation of Akt/eNOS/NO pathway involves in cardiomyocyte protection of emodin against homocysteine. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mechanism of phase transition from X2-RE 2 SiO 5 to apatite is revealed. • The formation of apatite in corroded Y 2 SiO 5 is inhibited by introducing Yb. • Silica-rich grain boundary is considered to reduce the corrosion degree. Environmental barrier coatings (EBCs) are usually coated on SiC ceramic or ceramic matrix composites (CMCs), in order to prevent the attack from corrosive media like water vapor and molten oxides. Solid-solutionizing strategy containing high-entropy engineering is considered as an effective way to mediate corrosion resistances of rare-earth silicates, which are promising candidates for the topcoats of EBCs. In this work, high-temperature corrosion behaviors of hot-pressed (Y 1− x Yb x) 2 SiO 5 ceramics have been investigated in a 50 %H 2 O–50 %O 2 environment at temperatures of 1573/1673/1773 K for 100 h. The main corrosion product of Y 2 SiO 5 is apatite phase, whose formation can be distinctly inhibited by introducing Yb. Consequently, introducing Yb avoids the tensile stress and cracks effectively, which are induced by the volume reduction due to the phase transition to apatite at elevated temperatures. The inhibition of apatite formation by introducing Yb is attributed to the relatively lower volatilization pressure of Yb 2 O 3 than Y 2 O 3 and the smaller cationic radius of Yb3+ than Y3+. Meanwhile, the composition deviations between grain boundary and grain surface results in the grain surface corrosion and ridge-like corrosion characteristics. [ABSTRACT FROM AUTHOR]

The MgB2 superconductor synthesized in a flowing argon atmosphere using nanometer magnesium powder as the raw materials, denoted as Nano-MgB2, has been studied by the technique of in situ high temperature resistance measurement (HT-RT measurement). The MgB2 phase is identified to form within the temperature range of 430–490 °C, which is much lower than that with the MgB2 sample fabricated in the same gas environment using the micron size magnesium powder, denoted as Micro-MgB2 and reported previously. The sample density of the Nano-MgB2 reaches 1.7 g/cm3 with a crystal porosity structure less than a μm, as determined by the scanning electron microscope (SEM) images, while the Micro-MgB2 has a much more porous structure with corresponding density of 1.0 g/cm3. This indicates that the Mg raw particle size, beside the sintering temperature, is a crucial factor for the formation of high density MgB2 sample, even at the temperature much lower than that of the Mg melting, ∼650 °C. The X-ray diffraction (XRD) pattern shows a good MgB2 phase with small amount of MgO and Mg and the transition temperature, TC, of the Nano-MgB2 was determined to be 39 K by temperature dependent magnetization measurements (M–T), indicating good superconducting properties. [Copyright &y& Elsevier]

Perovskite-structured Sn- or Ta-doped Li 0.24–(q –4) x La 0.587 Ti 1– x M x O 3 (LLTM x O, M = Sn or Ta, q is equal to the valence of M, x = 0, 0.02, 0.04, 0.06, 0.08) solid electrolytes are prepared by the pressureless sintering method for Li ion batteries. The phase composition, microstructure and electrical performance as a function of the type of doping elements and the amounts corresponding are studied by XRD, Raman spectrometer, SEM and electrochemical impedance spectroscopy. The LLTM x O pellets sintered at 1350 °C for 12 h have high relative densities (96.2%–97.9%) and high conductivities, where the total conductivity of LLTTa 0.04 O and LLTSn 0.02 O reach 4.09 × 10−4 S cm−1 and 2.98 × 10−4 S cm−1 at room temperature (RT) respectively. Compared with the pure specimen (1.52 × 10−4 S cm−1), the total conductivities of the doped specimens are more than doubled. In addition, Sn or Ta doping can significantly reduce the activation energy, with LLTTa 0.04 O exhibiting the low activation energy of 0.31 eV. The improvement in the total conductivity is attributed to the expansion of the Li ion transmission channels, the improvement of the relative density and the rise in the Li ion vacancy concentration, which are all resulted from the effect of dopant. • LLTM x O with high relative density were synthesized by pressureless stinering. • The LLTTa 0.04 O has a high conductivity of 4.09 × 10−4 S cm−1 at RT. • The LLTTa 0.04 O has a low activation energy of 0.31 eV. • Ta or Sn doping can more than double the total conductivety. • The effects of Sn or Ta doping on the total conductivity were investigated. [ABSTRACT FROM AUTHOR]