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This study explored the impact of enzymatic grafting modification on the structure and functional properties of pectin, aiming to provide a scientific foundation for the development of novel food packaging materials with bioactive properties. Using lipase as a catalyst, p-hydroxybenzoic acid and gallic acid were grafted onto pectin molecules. The structure of the modified pectin was characterized using 1H NMR, FTIR, and XPS analytical techniques, and its antioxidant and antibacterial activities were evaluated. The results showed that the grafting rates of p-hydroxybenzoic acid-modified pectin (Hb-Pe) and gallic acid-modified pectin (Ga-Pe) reached 21.8% and 22.9%, respectively. Notably, compared to unmodified pectin, Ga-Pe exhibited significantly (P<0.05) enhanced DPPH free radical scavenging capacity (69.6%) and β-carotene bleaching inhibition capacity (65.5%), while the improvement in antioxidant activity of Hb-Pe was limited, with the two indicators being only 5.54% and 28.6%, respectively. Furthermore, the inhibition zone diameters of the two modified pectins against Escherichia coli and Staphylococcus aureus were 15.7, 13.3 mm (Hb-Pe) and 16.6, 12.6 mm (Ga-Pe), respectively, which were significantly (P<0.05) higher than those of unmodified pectin. This study confirms that enzymatic grafting modification can effectively enhance the bioactivity of pectin, providing a new approach for extending the shelf life of food products. [ABSTRACT FROM AUTHOR]

The study proposes a Kalman Filter Family-schemed algorithm to identify the vehicle's parameters and evaluate the road roughness simultaneously, based on the response of an adapted monitoring vehicle. The vehicle is simplified as a three-dimensional multi-body system consisting of the unsprung mass of wheels and the sprung mass of the car body, connected by springs and dampers that represent the suspension system. Accelerometers and a gyroscope measure the accelerations or angular velocity of different positions of the vehicle during vibrations. The Kalman filter (KF) with unknown inputs enables the prediction of the car body's accelerations from those of wheels. On the other hand, the Augmented KF can compute the accelerations of wheels based on the car body's accelerations. Thus, an inner-systemic objective function incorporating the vehicle's parameter is built between the predicted and measured accelerations and solved in an optimized manner with the Genetic Algorithm, so that an individual complicated impact test or bump test is avoided. The numerical examples carry out field tests on a 900 m long standardized test road under two scenarios of with and without a bump. The road roughness estimated by these two KF methods from different measurements is used to calculate the International Roughness Index (IRI) and further the Riding Quality Index, which are compared with those directly provided by a standardized laser IRI profilometer. Accordance in between confirms the accuracy of the proposed algorithm under different scenarios. The analysis underlines the measurements from unsprung wheels that contact directly with the road enable a more accurate estimation of road roughness than those from the sprung car body. In addition, a vehicle speed lower than 40 km/h can provide a better estimation of the road profiles. [ABSTRACT FROM AUTHOR]

The development of efficient non-precious metal electrocatalysts for oxygen reduction reaction (ORR) to replace Pt-based methods is crucial for the applications of fuel cells and metal–air batteries. In this study, a bimetallic M-N-C catalyst with highly dispersed dual-atom Fe/Mn-Nx sites immobilized on N-doped bamboo-like carbon nanotubes is prepared by the ball-milling and calcination of dual-MOFs as precursors. The rich N-doping and abundant M–Nx species contribute to the excellent intrinsic ORR activity of the catalyst, and the unique bamboo-like nanotubes morphology is beneficial for facilitating electron transfer and mass transport while simultaneously enabling the exposure of active sites. As expected, the optimized Z-Fe1Mn1-NC catalyst exhibits efficient ORR activity with a half-wave potential (E1/2) of 0.80 V in acid and 0.82 V in alkaline, and a higher electrochemical stability with the current density maintained at 91% (in 0.1 M KOH) and 86% (0.1 M HClO4) of its initial current density after 15 h of a chronoamperometric test at a high potential of 0.7 V. When further applied to Zn–air batteries, the catalyst also delivers a high open-circuit voltage, large power density, and outstanding rate performance. This work provides a novel means of designing dual metal M–Nx site-based M-N-C catalysts for ORR sustainable energy applications. [ABSTRACT FROM AUTHOR]

Dignified liturgies (weiyi 威儀), one of the fundamental concepts in the Taoist scriptures, shows the overall image of Taoism displayed at the altar of the retreat (zhai 齋) and offering (jiao 醮) rituals. By examining the weiyi and Weiyi Masters in Taoist history, the dignified image of Taoist priests, the dignified duties of ritual masters, and the weiyi at the altar of the zhai and jiao rituals, we argue that the weiyi, which embodies the sacred dignity of the zhai and jiao altar, is key to understanding the meaning and function of Taoist zhai and jiao rituals. An overview of the weiyi is a new perspective in Taoist ritual studies, as in Taoist history its image as a state religion was displayed through dignified liturgies. [ABSTRACT FROM AUTHOR]

Adult stem cells, a class of cells that possess self-renewal and differentiation capabilities, modulate tissue regeneration, repair, and homeostasis maintenance. These cells undergo functional degeneration during aging, resulting in decreased tissue regeneration ability and increased disease incidence. Thus, it is essential to provide effective therapeutic solutions to preventing the aging-related functional decline of stem cells. Quercetin (Que) is a popular natural polyphenolic flavonoid found in various plant species. It exhibits many beneficial effects against aging and aging-related diseases; however, its efficacy against adult stem cell aging remains largely unclear. Drosophila possesses a mammalian-like intestinal system with a well-studied intestinal stem cell (ISC) lineage, making it an attractive model for adult stem cell research. Here, we show that Que supplementation could effectively prevent the hyperproliferation of ISCs, maintain intestinal homeostasis, and prolong the lifespan in aged Drosophila. In addition, we found that Que could accelerate recovery of the damaged gut and improve the tolerance of Drosophila to stressful stimuli. Furthermore, results demonstrated that Que prevents the age-associated functional decline of ISCs via scavenging reactive oxygen species (ROS) and inhibiting the insulin signaling pathway. Overall, our findings suggest that Que plays a significant role in delaying adult stem cell aging. [ABSTRACT FROM AUTHOR]