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Considering the current issues such as low integration, imprecise pressure adjustment, poor network communication performance, and lack of maintainability in traditional braking control system of autonomous-rail rapid tram, the paper introduces a new generation of electro-pneumatic braking control technology. In the electronic control section, the traditional braking control and pressure regulation modules are combined into an integrated electronic control unit. In the pressure regulation integrated module section, multiple functional valves such as pressure regulating valve, emergency solenoid valve, and remote relief valve are integrated into one module. This simplification of the air circuit layout optimizes space use and centralizes control functions. This electro-pneumatic braking control system employs a pressure regulating valve that has been fully verified by rail transit, coupled with a new pressure regulating algorithm of the electronic control unit, making pressure regulation more stable, with higher accuracy and fewer actions. Additionally, the application of dual Ethernet architecture enhances data transmission quantity and efficiency by several times compared to traditional CAN communication, considerably improving network communication capabilities and maintainability levels. The braking control system has completed ground combined test and third-party vehicle test, and has been installed and applied in the latest hydrogen energy autonomous-rail rapid tram, demonstrating excellent overall performance.

The electro-dynamic braking capacity of hydrogen-powered autonomous-rail rapid tram is severely limited by the state of charge (SOC) of the energy storage battery and the operational status of the hydrogen fuel cell. When the energy storage battery is near its full charge state and the hydrogen fuel cell continues to generate power, the storage battery is unable to store the electrical energy generated from electro-dynamic braking, leading to the failure of the electro-dynamic braking function. To maximize the electro-dynamic braking capacity of hydrogen-powered autonomous-rail rapid trams, this paper proposes an electro-dynamic braking control strategy based on pedal deceleration demand. It firstly calculates the total vehicle electro-dynamic braking force based on brake pedal stroke and load status. It then combines the current energy status of the storage system and the hydrogen fuel cell system to initiate a brake torque request to the traction system. It also calculates the electro-dynamic braking force corresponding to the deceleration required by the brake pedal stroke, optimizing the output of electro-dynamic braking force under different load, intermediate gear placement, and medium-low speed conditions. The test results show that with this electro-dynamic braking control strategy, the train fully exploits its electro-dynamic braking capacity under medium-low gear placement and medium-low speed working conditions in AW0 circumstances. It meets the design requirements for regenerative braking energy recovery of hydrogen-powered autonomous-rail rapid tram under the current electro-dynamic braking system architecture.

[Objective] In the context of a large number of rural labors migrating to cities and towns, clarifying the impact of labor transfer on the green production efficiency of grains for farming households has important policy implications in promoting the steady improvement of green production efficiency and promoting sustainable development of agricultural ecology.[Methods] Based on the survey data of 770 grain-producing farming households from Hubei and Henan Provinces, this study used the data envelopment analysis-slacks-based measure (DEA-SBM) model to calculate the green production efficiency of grains, and used the Tobit model to demonstrate the impact of labor transfer and technology extension on the green production efficiency of grains.[Results] The research showed that labor transfer had an inhibitory effect on the green production efficiency of grains for farming households in both the temporal and spatial dimensions. Government green technology extension measures could promote the improvement of green production efficiency of grains and effectively alleviate the negative impact of labor transfer on green production efficiency of grains. The mitigating effect of technology extension services on the green production efficiency of farming households was limited by the age and income of farmers. For young and high-income farmers, its mitigating effect is insignificant. [Conclusion] Therefore, we should improve the rural labor security mechanism, expand the promotion channels of green production technologies, and focus on the promotion of green production technology for older and low-income farming households, to promote the improvement of green production efficiency of grains and effectively speed up the process of high-quality agricultural development.

In the “Ecological Protection Law of the People’s Republic of China on the Qinghai Tibet Plateau” released in April 2023, it is stipulated that “the state strengthens the ecological protection and restoration of the Qinghai Tibet Plateau, adheres to the integrated protection and restoration of mountains, rivers, forests, fields, lakes, grasses, sands, and ice, and implements a systematic governance that focuses on natural restoration and combines natural restoration with artificial restoration.” Currently, there is relatively little research on the ecological restoration evaluation index system in high-altitude areas represented by the Qinghai Tibet Plateau in China. This article studies the climate and soil characteristics of the Qinghai Tibet Plateau region and selects ecological restoration evaluation index systems suitable for high-altitude areas, including biological and community evaluation, soil and water conservation function evaluation, soil and water physical and chemical property evaluation, and landscape pattern evaluation.

This study aimed to investigate the effects of Schisandra Chinensis Fructus polysaccharide (SCP) on learning and memory, hippocampal antioxidant activity and Keap1/Nrf2 signal transduction pathway in an aging mouse model. The step-down test was used to observe learning and memory. Biochemical analysis was used to detect Superoxide dismutase (SOD) and malondialdehyde (MDA) levels. Nrf2, HO-1, and Keap1 gene expression in the hippocampus were measured by quantitative real-time polymerase chain reaction (qRT-PCR). SCP can improve the learning and memory ability (P

Multiple resonance (MR) emitters are promising for the next-generation wide color gamut organic light-emitting diodes (OLEDs) with narrowband emissions; however, they still face intractable challenges such as concentration-induced emission quenching, exciton annihilation, and spectral broadening. In this concept, we focus on an advanced molecular design strategy called “sterically wrapping of MR fluorophores” to address the above issues. By isolating the MR emission core using bulky substituents, intermolecular interactions can be significantly suppressed to eliminate the formation of unfavorable species. Consequently, using the newly designed emitters, optimized MR-OLEDs can achieve high external quantum efficiencies of >40% while maintaining extremely small full width at half maxima (FWHMs) of

Both seed germination and subsequent seedling establishment are key checkpoints during the life cycle of seed plants, yet flooding stress markedly inhibits both processes, leading to economic losses from agricultural production. Here, we report that melatonin (MT) seed priming treatment enhances the performance of seeds from several crops, including soybean, wheat, maize, and alfalfa, under flooding stress. Transcriptome analysis revealed that MT priming promotes seed germination and seedling establishment associated with changes in abscisic acid (ABA), gibberellin (GA), and reactive oxygen species (ROS) biosynthesis and signaling pathways. Real‐time quantitative RT‐PCR (qRT‐PCR) analysis confirmed that MT priming increases the expression levels of GA biosynthesis genes, ABA catabolism genes, and ROS biosynthesis genes while decreasing the expression of positive ABA regulatory genes. Further, measurements of ABA and GA concentrations are consistent with these trends. Following MT priming, quantification of ROS metabolism‐related enzyme activities and the concentrations of H2O2 and superoxide anions (O2−) after MT priming were consistent with the results of transcriptome analysis and qRT‐PCR. Finally, exogenous application of GA, fluridone (an ABA biosynthesis inhibitor), or H2O2 partially rescued the poor germination of non‐primed seeds under flooding stress. Collectively, this study uncovers the application and molecular mechanisms underlying MT priming in modulating crop seed vigor under flooding stress. [ABSTRACT FROM AUTHOR]

Foreshore slope is crucial in designing beach berm nourishment schemes and understanding coastal responses to wave forces. Beach berm nourishment often suffers from a high loss rate, necessitating theoretical research and design parameter comparison to mitigate these losses early on. This study uses Bagnold's energy conservation method and the small-angle approximation method to establish a relationship between cross-shore sediment transport and foreshore slope. The feedback mechanism between these factors shows that when the foreshore slope is fewer than 10 degrees, a smaller initial slope results in a reduced rate of sediment transport. Over time, the foreshore slope decreases and eventually reaches equilibrium, promoting the formation of an offshore sandbar, which helps reduce sediment loss. Using data from Guanhu Beach in Dapeng Bay, this study constructs a realistic numerical beach model to simulate the dynamic behavior of beach profiles with varying foreshore slopes under the influence of monsoon waves and storm surges. The simulation results support the feedback mechanism findings, demonstrating that profiles with minimal foreshore slopes experience the least initial sediment loss, thus facilitating sandbar formation more effectively. These insights can inform beach berm nourishment strategies, emphasizing early-stage efforts to expand beach areas and reduce sediment loss. [ABSTRACT FROM AUTHOR]