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The Youden index is often used to measure the effectiveness of biomarkers and aids to find the optimal cutoff point. Since pooled specimens have been shown to be an effective cost-cutting technique, we proposed the exact inferential procedures for the Youden index and its associated cutoff point based on the pooled specimens under the gamma or the inverse Gaussian assumption. The generalized confidence intervals (GCIs) were proposed for the Youden index and its associated cutoff point. Monte Carlo simulations were used to assess the performance of the proposed GCIs. The simulation results show that the proposed GCIs outperformed existing methods such as the bootstrap- p CIs in terms of the coverage probability. Finally, the proposed procedures were illustrated by an example. [ABSTRACT FROM AUTHOR]

Understanding the composition and structure of forest trees is crucial to comprehending the properties and functions of forests. It also helps in implementing effective management strategies for sustainable resource utilization. Our study analyzed the structural dynamics of the old-growth mixed oak forests in the Xiaolongshan Forest region, focusing on three long-term monitoring plots (A, B, C). We examined the tree species composition, diameter distribution, mortality, and recruitment dynamics of different successional species groups, as well as the spatial distribution patterns of living and dead trees, with surveys conducted every five years. The findings indicate: (1) Plot A experienced a decline in stand density and species diversity during the survey period, with the Importance Value Index (IVI) of pioneer successional species continually decreasing in plots B and C. (2) The tree diameter distribution structure in plot A significantly differed from other plots, showing notable change between 2007 and 2012. (3) All plots exhibited lower, well-balanced community-level demographic parameters based on stem number, but a higher recruitment rate for later successional species groups based on basal area. (4) Dead individuals in plot A had a slight clustering distribution, while the other plots showed a random distribution. We conclude that the individual growth rate significantly impacts the dynamics of the natural Quercus aliena var. acuteserrata forest, with pioneer species groups being gradually replaced by early or late-successional species groups in the succession process. [ABSTRACT FROM AUTHOR]

Temperature rise of the tubular permanent magnet linear generator (TPMLG) might lead to insulation failure and demagnetization of permanent magnets, affecting the safe and stable operation of other equipment and the entire system. Herein, a bidirectional electromagnetic–thermal coupling method for analyzing the electromagnetic loss and thermal characteristics of a TPMLG considering the effect of increased temperature on the permanent magnet was proposed. To study the electromagnetic–thermal characteristics of the TPMLG under stable power generation, a two-dimensional electromagnetic field model and a three-dimensional temperature field model were established and coupled. The temperature field of the TPMLG was numerically calculated using computational fluid dynamics over finite volume method under natural air cooling and forced air cooling conditions. Effects of loss and air flow velocity on the steady temperature field were investigated. Results indicated that copper loss increased by 24.5% considering the influence of temperature rise. The windings' top central position in the TPMLG was the spot with the highest temperature of 127.8 °C and there was a potential demagnetization risk for the permanent magnets. Some reference for future research of clarifying thermal characteristics and cooling design was provided. [ABSTRACT FROM AUTHOR]

Kafirins are the primary storage proteins in sorghum kernels that provide amino acids for seed germination. The highly proteolytic resistant γ‐ and β‐kafirins form the cross‐linked outer layers that encapsulate α‐kafirins to generate protein bodies, resulting in poor digestibility of sorghum grains. The sorghum kafirins thus contribute to the poor quality of the kernels. The nutritional quality and digestibility of sorghum grains can be improved by reducing the contents of kafirin. γ‐Kafirin is encoded by the K2G gene, which is located on sorghum chromosome 2. In this study, we used CRISPR/Cas9 gene editing to target the K2G gene to create new sorghum lines with reduced levels of kafirin. A guide RNA (sgRNA) was designed to introduce mutations in the CDS region that encodes the endoplasmic reticulum signal peptide of γ‐kafirin. The pK2GsgRNA/Cas9 vector was transformed into sorghum using the pollen‐mediated transformation method. Sequencing of the transformants showed that three out of 24 transgenic plants contain genetic mutations in the targeted region. Compared with the wildtype, the γ‐kafirin contents of the mutant plants decreased by 12.75%–19.22%, and the protein digestibility of the mutant kernels increased by 26.91%–74.31% in raw flour. Although the grain weights remained comparable to those of the wildtype, the growth of the mutant plants was more vigorous as the mutant shoots grew taller and thicker compared with those of the wildtype. Our work advances the ability to improve the digestibility of an important crop. The resulting quality improvements can also be rapidly deployed for breeding and generation of transgene‐free, improved cultivars of sorghum, a major crop worldwide. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) with aggregation-induced emission photosensitizers (AIE-PSs) has attracted increasing attention for their enhanced fluorescence and reactive oxygen species (ROS) generation abilities upon aggregation. However, it is difficult for AIE-PSs to simultaneously achieve long-wavelength excitation (>600 nm) and high singlet oxygen quantum yield, which restricts their application in deep-tissue PDT. In this study, four novel AIE-PSs were developed by appropriate molecular engineering, and their absorption peaks shifted from 478 to 540 nm with a tail extending to 700 nm. Meanwhile, their emission peaks were also moved from 697 nm to 779 nm with a tail extending over 950 nm. Importantly, their singlet oxygen quantum yields successfully increased from 0.61 to 0.89. Moreover, TBQ, the best photosensitizer developed by us, has been successfully applied to image-guided PDT in BALB/C mice bearing 4T1 breast cancer under red light (605 ± 5 nm) irradiation, with IC50 less than 2.5 μM at a low light dose (10.8 J cm−2). The success of this molecular engineering indicates that increasing the number of acceptors is more effective at red-shifting the absorption band of AIE-PSs than increasing the number of donors, and extending the π-conjugation of acceptors will red-shift the absorption–emission band, increase the maximum molar extinction coefficient, and improve the ROS generation ability of AIE-PSs, thus providing a new strategy for the design of advanced AIE-PSs for deep-tissue PDT. [ABSTRACT FROM AUTHOR]