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Low solar irradiance reaching the canopy due to fog and heavy haze is a significant yield-limiting factor worldwide. However, how plants adapt to shade stress and the mechanisms underlying the reduction in leaf photosynthetic capacity and grain yield remain unclear. In this study (conducted during 2018–2021), we investigated the impact of light deprivation (60%) at the pre-anthesis and post-anthesis stages on leaf carboxylation efficiency, source-to-sink relationships, sucrose metabolism, and grain yield of wheat cultivars with contrasting shade tolerance. Shade stress decreased stomatal conductance, stomatal limitation value, intrinsic water use efficiency, rubisco activity, and carboxylation efficiency of flag leaves during grain-filling, whereas intercellular CO2 concentration increased. These findings indicate that non-stomatal limitation reduces the net photosynthesis rate in a weak-light environment. Shade-tolerant cultivars (MM-51 and CM-39) adapted to low-light conditions via a higher leaf area of flag leaves, light interception rate, and chlorophyll a and b contents; this increased non-structural carbohydrates and sucrose contents in developing grains, ultimately decreasing yield loss by shade stress. Pre-anthesis shading resulted in a greater yield loss than post-anthesis shading because of decreased plant biomass, grain number per spike and 1,000-kernel weight. This study indicates that Rubisco-mediated non-stomatal limitation reduces P N and sucrose content in plants exposed to low-light stress, contributing to decreased grain yield. Our study provides information on the mechanism underlying shade stress tolerance, which will help design future strategies for reducing yield loss in the context of global dimming. [ABSTRACT FROM AUTHOR]

Reliability evaluation during aero-engine operation is one of the key issues in the field of reliability evaluation of aero-engine,and the reasonable evaluation method can improve the reliability analysis efficiency and accuracy,therefore a method to support the evaluation of aeroengine operation reliability in the process of aircraft mission is proposed in this paper.Based on the characteristics of flight mission and aeroengine,the quick access recorder(QAR)information is used as the analysis data to analyze the operational reliability,and the operation reliability is analyzed by considering the current operating environment,the transient state of the aircraft,and the current working state of the engine.The random forest algorithm is combined with stratified sampling method to fit,predict and calculate the feature importance.B737-800 flight mission from Beijing to Urumqi is taken as an example to verify the effectiveness and feasibility of the method.The results show that the proposed reliability evaluation method can solve the problem of data processing difficulty caused by large amount of data and high dimension in the process of aeroengine operation.

This study was to investigate the relationship between metacognition and the mathematical modeling skills of high school students, as well as the mediating role of computational thinking. A cluster sampling method was adopted to investigate 661 high school students, using the metacognition scale, computational thinking scale, and mathematical modeling skill test questions. The results showed that metacognitive knowledge and metacognitive monitoring had a direct and positive correlation with high school students' mathematical modeling skills. Additionally, the critical thinking dimension of computational thinking mediated the relationship between metacognitive knowledge, experience, monitoring, and mathematical modeling skills. These findings indicated that sufficient metacognition could improve the critical thinking of high school students' computational thinking and enhance their mathematical modeling skills. [ABSTRACT FROM AUTHOR]

Fisheries and bottom seawater data were collected in July in 2022 and 2023 from 15 sampling stations in the Huanghe River estuary and adjacent seas in China. The patterns of functional alpha and beta diversity of fish communities in this area and their relationships with environmental factors were studied using trait-based analysis. Five functional classifications, which included 16 functional traits, four functional alpha diversity indices (functional richness, functional evenness, functional divergence, and community-weighted mean), three functional beta diversity indices (functional beta diversity and its turnover and nestedness components), and 14 bottom environmental factors were considered. The dominant traits of fish communities were the following: benthivorous feeding habits, small and front-facing mouths, high trophic level, demersal, anguilliform, low growth coefficient, medium resilience, low vulnerability, and adapted to warm temperate conditions. The dominant migration traits and types of fish eggs varied by year, and fish abundance was the main factor affecting the dominant traits of the communities. The results of multiple regression on distance matrices and variance partitioning analysis indicated that ammonia nitrogen content, total phosphorus content, and pH were the main environmental factors that affected fish functional diversity. The N/P ratio had a bottom-up control effect on fish functional diversity. Our findings also revealed that high pH gradients and distant geographical distances can inhibit trait turnover in fish communities. [ABSTRACT FROM AUTHOR]

A novel MXene/cadmium azide nanocomposite with a low input energy and high output power is designed by self-assembly of Cd ions on the MXene layers and subsequent in situ azidation in a solution reaction. The research result shows that cadmium azide nanoparticles with a uniform size of ∼50 nm are well dispersed on the MXene nanosheet's surface, which is benefited from the rich functional groups on the MXene surface that can effectively immobilize and prevent the aggregation of the nanoparticles through electrostatic interaction. The thermal decomposition temperature (378.42 °C) and crystal structure of cadmium azide show no noticeable change after hybridizing with the MXene; more positively, the required input energy of the MXene/cadmium azide nanocomposite is significantly reduced, which is verified by its electric initiation input voltage of just 4.65 V. In addition, detonation can be realized by loading a less amount of the MXene/cadmium azide nanocomposite. These results demonstrate that the MXene/cadmium azide nanocomposite has the potential to be used as detonators in high-temperature environments. [ABSTRACT FROM AUTHOR]

Lack of soil moisture and phosphorus deficiency limits wheat grain yield in dryland areas. However, the moisture-conserving effect of straw mulching combined with phosphor fertilization on fertile florets per spike (FFS) and grain yield remains unclear. During the 2020–2021 and 2021–2022 growing seasons, we investigated the combined effects of straw mulching (0 and 8000 kg ha−1) and phosphorus fertilization (0, 75, and 120 kg P2O5 ha−1) on spike development, assimilates' availability, and the photosynthetic properties of flag leaves by conducting a field experiment. Compared with no straw mulch control, straw mulching increased fertile spike, grain number per spike (15.6%), and grain yield (22.6%), and grain number per spike was the most important contribution to increasing wheat grain yield (46%). An increase in grain number per spike is associated with FFS. Compared with no straw mulch control, straw mulching increased FFS by 19.5%, and it increased with increasing phosphorus fertilization levels. Moreover, straw mulching combined with phosphorus fertilization promoted the light compensation point (LCP), light saturation point (LSP), net photosynthetic rate (Pn), Chl b, and the maximal photochemical efficiency of photosystem II (Fv/Fm) of flag leaves to produce carbohydrates. Our study has shown that the primary factor for the divergence in FFS under straw mulching and phosphorus application was the efficiency of assimilate utilization in the spike, which ultimately led to increased grain number per spike and grain yield. [ABSTRACT FROM AUTHOR]