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Steamed bread, noodles, deep-fried dough sticks and other noodle foods are an important part of our diet, and gluten protein is an important component of noodle foods. Common food processing techniques used to prepare noodles, including heating, freezing, mechanical processing, fermentation, and electric field treatment, alter the hydrophobic disulfide bond of the protein, denature and aggregate the protein, and cause other intricate physical and chemical changes, all of which have an impact on the texture and flavor of the finished noodle product. This paper mainly introduces the current research status of the influence of processing methods such as heating, freezing, crushing, kneading, extrusion, fermentation, and electric field processing on the structure and properties of the gluten protein.

Metasurface provides subwavelength structures for manipulating wavefronts of light. The benefits of subwavelength components offer a continuous modulation of amplitude, phase, and polarization, thus eliminating the production of higher-order images and improving the utilization of light intensity. Despite the rapid progress in this field, multiparameter control of light using single layer metasurface is rarely reported. In fact, multiparameter control of light helps to improve information storage capacity and image fidelity. With simultaneous manipulation of polarization and amplitude at each pixel, it is possible to encode two separate images into one metasurface and reconstruct them under proper conditions. In a proof of concept experiment, we demonstrate an independent display of two binary images at the same position with polarization de-multiplexing from a single metasurface. This unique technology of encoding two images through amplitude and polarization manipulation provides a new opportunity for various applications in, such as encryption, information storage, polarization holograms, optical communications and fundamental physics.

This study was conducted in order to explore the effect of distilled spirit (with 52% alcohol content, V/V) made from grapes on the intestinal flora of hyperuricemic mice. Six-week-old specific pathogen free (SPF) male mice were randomly divided into low-dose, medium-dose, high-dose distilled spirit, control, hyperuricemic model and ethanol groups. After continuous gavage administration for seven days, the content of short chain fatty acids in mouse feces was determined by gas chromatography mass spectrometry (GC-MS). and gut microbiota composition was analyzed by 16S rDNA gene high-throughput sequencing on the Illumina MiSeq platform. Results indicated that the distilled spirit at low and medium doses could improve the diversity of gut microorganisms, significantly increase the relative abundance of Bacteroidota (P < 0.05), reduce the relative abundance of Firmicutes (P < 0.05), improve intestinal dysbacteriosis, increase Firmicutes to Bacteroidota ratio, and enhance the relative abundance of intestinal beneficial bacteria such as Butyricicoccus, Ruminococcaceae NK4A214_group, Roseburia, Anaerotruncus, and Clostridiaceae in hyperuricemic mice. Meanwhile, the contents of acetic acid, propionic acid and n-butyric acid in the medium-dose distilled spirit group were significantly higher than those in the model and ethanol groups (P < 0.05). Therefore, daily intake of the distilled spirit at 1 or 2 mL/kg mb can improve the imbalance of gut flora in hyperuricemic mice and have a positive regulatory effect on the intestinal microecology.

Disturbance observer-based sliding mode control (SMC) on the active vertical suspension (AVS) is developed to suppress the car body's rigid and flexible vibration to improve ride comfort for a high-speed rail vehicle. A vertical-dynamics-intended vehicle model is foremost built with the bounce, pitch, and bending mode of the car body involved. Two sliding surfaces and disturbance observers are then designed for SMC, which only require the car body states, obviating the bogies' states. The observer is successful in estimating the effect of unknown track irregularities perturbation as well as externally straightforwardly excitations on the car body with good accuracy. Control efficacy is verified through comparison with passive cases and sky-hook controls. With modal damping below 2% in passive cases, the mode shape function, especially with large displacement at the suspension support, would enlarge the car body acceleration. Moreover, the longitudinal traction rod can significantly multiply the flexible vibration at certain speeds. Comparative studies indicate that SMC provides satisfactory outcomes in the rigid and bending vibration suppression when all the car body's three modes are considered in the sliding surface. However, it requires a high-frequency response actuator and allows a tighter tolerance of the control time delay than the sky-hook control. [ABSTRACT FROM AUTHOR]

Active yaw dampers (AYDs) show promise in addressing the carbody and bogie hunting issues of high-speed rail vehicles. However, the bifurcation behaviour under active control and the control law for hunting instability still require investigation. This study presents a comprehensive description of the linear control law, which can be simplified to various schemes, including skyhook damping, groundhook stiffness, modal, and blended schemes. The bifurcation behaviour under active control was analysed using a simplified lateral-dynamics-intended seven DOFs vehicle model and verified using a 3D full DOFs model in SIMPACK. Besides the well-known Hopf bifurcation, results also revealed a branching point (BP) and two new stable asymmetric equilibria. Although the asymmetric equilibria born through BP are stable, BP bifurcation should still be avoided for wheel flange contact and derailment concerns. Possible control laws are explored for two hunting scenarios: carbody hunting and bogie hunting. For carbody hunting cases, the control force can be either a linear function of bogie yaw displacement or a linear weighting function of bogie lateral and carbody roll velocity. The dominant frequency of the actuated force falls below 2 Hz, with a peak of 1.6 kN, and the allowable time delay is 70 ms. For bogie hunting cases, the control force can be a linear function of either bogie yaw displacement or velocity. In other words, both the groundhook stiffness and damping strategy are applicable. However, the actuated force contains several relatively high-frequency components (6∼13 Hz), which poses challenges to the control system and actuators, and the allowable time delay is relatively small. [ABSTRACT FROM AUTHOR]

Active metasurfaces utilize semiconductor carrier modulation, offering an approach for spatial light modulation with advantages in speed, efficiency, and power consumption. Here, we present a method for designing programmable metasurfaces that leverage the plasma dispersion effect of semiconductors to tune terahertz wave phase. By integrating the PN junction into the metasurface unit and adjusting the relative permittivity of the PN junction through voltage control, the reflected wave phase can be effectively manipulated. The designed metasurface enables continuous phase modulation of up to 270° around 0.4 THz, with an average reflection efficiency of 30% and potential modulation speed in the GHz range. Additionally, by configuring different phase distributions, the metasurface can steer terahertz beams at different angles, achieving a far-field radiation peak gain of 13 dB. This proposed programmable metasurface shows great potential for applications in terahertz communication and imaging. [ABSTRACT FROM AUTHOR]

Hunting stability is a critical aspect of the dynamic performance of high-speed trains. However, the current evaluation criteria only address heavy hunting motion, and they require supplementation and improvement to meet the increasing requirements of dynamic performance. Therefore, a study was conducted to develop an identification method for small-amplitude bogie hunting (SABH) motion. A total of 39,816 samples were obtained from field-measured bogie lateral acceleration and manually labelled as normal and SABH. The distribution comparison, Pierce coefficient, and importance ranking showed that harmonic character-related features (the autocorrelation coefficient, approximate entropy and etc.) should be considered more for SABH identification than amplitude-related features (maximum and RMS). The most critical features for SABH identification were the autocorrelation coefficient and spectral frequency spread. The classifier performance comparison showed that the decision tree was the best-performing classifier, followed by the support vector machine, while the linear discriminant, K-nearest neighbour, and naive Bayes classifiers were less effective. Sensitivity analysis indicated that the proposed method worked well with a sampling frequency of 50–200 Hz and a window length of 5–10 s. This research provides theoretical support for hunting instability monitoring and real-time active control studies for high-speed trains. [ABSTRACT FROM AUTHOR]

Erwinia beijingensis can cause the bacterial soft rot disease of Pleurotus eryngii. In order to clarify the function of glycosyltransferase in E. beijingensis, a recombinant expression vector was constructed to express and purify the glycosyltransferase in this pathogen. The protein activity was measured, and the interactions between proteins were analyzed. The results showed that the prokaryotic expression vector was successfully constructed, 4 soluble proteins were obtained, and MshA, WbnH2, EpsH and TuaG proteins were purified by affinity chromatography column. The activity assay showed that four proteins preferentially used UDP galactose. GST pull down results confirmed that WbnH2 and TuaG proteins interacted with MshA and EpsH proteins in vitro, respectively. Above results laid a foundation for the subsequent study on the function of the glycosyltransferase gene in E. beijingensis. [ABSTRACT FROM AUTHOR]

This investigation integrates an alternative fully-parameterized approximation of nonlinear wheel/rail interaction into a simplified vehicle model, and a two-parameter Hopf bifurcation analysis is conducted to reveal the influence of the wheel/rail contact geometry and secondary suspension parameters for high-speed rail vehicles. The bifurcation diagram is compared among the 6 DOFs bogie model, linear and nonlinear 7 DOFs vehicle model, nonlinear 17 DOFs vehicle model, and 3D full DOFs vehicle model. It shows that the nonlinear 7 DOFs vehicle model can meet the requirement of both carbody hunting and bogie hunting simulations. 6 DOFs bogie model can only be used in bogie hunting bifurcation analysis. Linear vehicle model would bring errors in either critical speed or limit circle magnitude. The divergences in the linear terms of rolling radius and contact angle polynomials are significant enough in field operation to cause a noticeable difference in Hopf bifurcation speed. Attention shall be paid to the shape of equivalent conicity and contact angle curve. The crucial parameters to the Hopf bifurcation include the series stiffness and damping coefficient of the yaw damper and the lateral damper damping. However, the requirement of suspension parameters for stability can conflict in carbody hunting and bogie hunting cases. [ABSTRACT FROM AUTHOR]