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BACKGROUND: This study aims to quantify the impacts of chilling at the grain filling stage on rice yield and grain quality. A factorial experiment with four levels of temperature and duration of chilling treatments at the early and late grain filling stages was conducted in 2017, 2018 and 2019. RESULTS: Per 10 °C·day increase in the accumulated cooling degree day at the early and late grain filling stages, the rice emergence–maturity duration was delayed by 0.8% (0.6%) and rice yield decreased by 2.2% (1.7%). Chilling at the early grain filling stage decreased the rice heading rate, while chilling at the late grain filling stage increased rice amylose but decreased protein content. For chilling treatment at the early grain filling stage, rice yield and grain quality were mainly correlated with seed‐setting rate, whereas for chilling treatment at the late grain filling stage the rice yield and grain quality were mainly correlated with 1000‐grain weight. CONCLUSION: This study improved the understanding of how chilling at the grain filling stages affects rice phenology, yield and grain quality, providing a theoretical basis for maintaining rice yield while ensuring grain quality. The results could be used to guide the rice‐growing community in combating chilling at grain filling stages. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Climate change has resulted in a continuous increase in the frequency and intensity of chilling events in cold regions. In Northeast China, chilling at the booting and flowering stages negatively affects japonica rice grain yield. In this field experiment study, we conducted a 2‐year temperature‐controlled experiment to investigate the effects of chilling temperature and duration applied at the booting and flowering stages on japonica rice. The results showed that chilling at the two study stages delayed the rice phenology and decreased the grain yield. In particular, japonica rice was more sensitive to chilling at the booting stage than at the flowering stage. The rice grain yield was reduced by more as the chilling temperature decreased and the chilling duration increased. As for the yield components, the spikelet fertility and grain number per spike were more sensitive to chilling at the booting stage than at the flowering stage. Variations in the grain yield per plant were primarily contributed by the differences in spikelet fertility and grain number per spike, especially the spikelet fertility. In addition, cooling degree days showed statistically significant negative correlations with grain yield per plant, grain number per spike and spikelet fertility. For every 10°C·day increase in CDD at the booting (flowering) stage, the grain yield per plant, spikelet fertility and grain number per spike decreased by 7.1%, 6.2% and 3.4% (3.9%, 5.0% and 1.2%) respectively. As the spikelet fertility and grain number per spike decreased, the sink capacity decreased as well with the increasing of allocated assimilation to the stem and leaf while decreasing the assimilation allocated to the panicle. Increasing cooling degree days at the booting and flowering stages increased the allocations of assimilation to the stem and leaf. As a result, less assimilation was allocated to the panicle. This study suggests that breeding cultivars to improve the spikelet fertility and grain number per spike could help to minimize the potential rice grain yield loss due to the increase in chilling events occurring at the booting and flowering stages. [ABSTRACT FROM AUTHOR]

In the landscape of photovoltaic research, carbon‐based perovskite solar cells (C‐PSCs) have attracted widespread attention due to their outstanding stability. However, compared to metal‐based PSCs, their power conversion efficiency (PCE) lags markedly behind. The key lies in two primary factors: First, the inefficiency of the carbon electrode in transporting and collecting carriers; second, the energy level mismatch with adjacent functional layers. These problems increase both the charge transport resistance and the charge injection barriers, thereby diminishing the overall efficiency of the device. In this study, an effective strategy is presented to tackle this issue by developing modular C‐PSCs that utilize dual carbon electrodes and implement multiscale modulation. This approach specifically focuses on three crucial aspects: establishing a highly conductive network, ensuring sufficient interfacial contact, and achieving well‐matched energy band alignment. By synergistically incorporating 0D carbon black (CB) and 1D carbon nanotube (CNT) into dual carbon electrodes, a resilient conductive network with enhanced interfacial contact is established, creating favorable conditions for efficient carrier transfer. Additionally, the energy level structure of CB is meticulously adjusted at the molecular scale by introducing individually adsorbed titanium (Ti) atoms, effectively addressing the energy level mismatch with the hole transport layer (spiro‐OMeTAD), and notably reducing the charge injection barrier at the interface. Based on the above strategy, the PCE of the C‐PSCs has undergone a remarkable enhancement from 15.27% to 22.45%. Moreover, the device shows excellent stability, with its PCE retaining over 95% of the initial value even after 1000 h of continuous operation under one‐sun intensity. [ABSTRACT FROM AUTHOR]

The effects of the rovibrational excitation of reactants in the N(2D) + D2(X1Σg+) → ND(X3Σ+) + D(2S) reaction are calculated in a collision energy range from the threshold to 1.0 eV using the time-dependent wave packet approach and a second-order split operator. The reaction probability, integral cross-section, differential cross-section and rate constant of the title reaction are calculated. The integral cross-section and rate constant of the initial states v = 0, j = 0, 1, are in good agreement with experimental data available in the literature. The rotational excitation of the D2 molecule has little effect on reaction probability, integral cross-section and the rate constant, but it increased the sideways and forward scattering signals. The vibrational excitation of the D2 molecule reduced the threshold and broke up the forward-backward symmetry of the differential cross-section; it also increased the forward scattering signals. This may be because the vibrational excitation of the D2 molecule reduced the lifetime of the intermediate complex. [ABSTRACT FROM AUTHOR]

The increasing frequency and intensity of low-temperature events in temperate and cold rice production regions threaten rice yields under climate change. While process-based crop models can project climate impacts on rice yield, their accuracy under low-temperature conditions has not been well-evaluated. Our six-year chamber experiments revealed that low temperatures reduce spikelet fertility from panicle initiation to flowering, grain number per spike during panicle development, and grain weight during grain filling. We examined the algorithms of spikelet fertility response to temperature used in crop models. Results showed that simulation performance is poor for crop yields if the same function was used at different growth stages outside the booting stage. Indeed, we replaced a parameter spikelet fertility algorithm of the ORYZA model and developed the function of estimating grain number per spike and grain weight. After that, the improved equation algorithm was applied to 10 rice growth models. New functions considered the harmful effects of low temperatures on rice yield at different stages. In addition, the threshold temperatures of the cold tolerance were set for different rice varieties. The improved algorithm enhances the model's ability to simulate rice yields under climate change, providing a more reliable tool for adapting rice production to future climatic challenges., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Objective: To observe the difference in the clinical therapeutic effects on bronchial asthma in children of different body constitutions treated with sanfu pingchuan plaster and sanjiu zhichuan plaster., Methods: One hundred and twenty-two children of bronchial asthma were divided into three groups according to TCM body constitutions, 42 cases in the qi deficiency constitution group, 40 cases in the yang deficiency constitution group and 40 cases in the phlegm damp constitution group. From 2011 to 2013, the acupoint plaster was applied to all of the children in the three groups during the dog days and the third nine-day period after the winter solstice each year. The average attack frequency and onset days of bronchial asthma and relevant immune function indicators were observed during treatment and 1 year after treatment in the children and the therapeutic effects were evaluated., Results: ①In 2014, the acute attacks of bronchial asthma were (1.2±0.9) times and (1.4±0.4) times in the qi deficiency constitution group and the yang deficiency constitution group, all lower than (3.0±0.5) times in the phlegm damp constitution group (both P <0.05) separately. ②After treatment, in the qi deficiency constitution group and yang deficiency constitution group, the values of IgG, IgA and IgM were all increased as compared with those before treatment (all P <0.05). ③The total effective rate was over 95% in the children of the three groups. The clinical control rates in the qi deficiency constitution group and the yang deficiency constitution group were higher apparently than that in the phlegm damp constitution group, indicating the significant difference statistically (both P <0.05)., Conclusions: The combined treatment of sanfu pingchuan plaster and sanjiu zhichuan plaster are effective on bronchial asthma in the children of different body constitutions. The therapeutic effects for the qi deficiency constitution and the yang deficiency constitution are more apparent than that for the phlegm damp constitution.