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Insecticidal Constructure and Bioactivities of Compounds from Ficus sarmentosa ***

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Agricultural Sciences in China 2011年第9期10卷 1402-1409页

作者： WANG Xue-gui WEI Xiao-yi HUANG King-yan shen li-tao TIAN Yong-qing XU Han-hong Key Laboratory of Natural Pesticide and Chemical Biology Ministry of Education/South China Agricultural University Guangzhou 510642 P.R.China Biorational Pesticide Research Laboratory Sichuan Agricultural University Chengdu 611130 PR.China South China Institute of Botany Chinese Academy of Sciences Guangzhou 510650 P.R.China

Insecticidal activities of the petroleum ether-, chloroform-, ethyl acetate-, and water-soluble fractions of the methanolic extract ofFicus sarmentosa var. henryi were assayed against Musca domestica adults. The chloroform- and ethyl acetate- soluble fractions were the most active with 92.6 and 88.9% mortalities （24 h after treatment） respectively. Therefore, the two fractions were combined and four compounds, isolated from the fractions by activity-guided fractionation, were elucidated as 7-hydroxycoumarin, apigenin, eriodictyol, and quercetin by spectroscopic method and displayed excellent insecticidal activities against adults of M. domestica and 4th instar larva of Aedes albopictus. Among those, 7- hydroxycoumarin showed the strongest insecticidal activities with lethal concentrations （LC50） values of 72.13 μg g^-1 sugar and 4.87 μg mL^-1 （48 h after treatment） against the test insects respectively. The cytoxicities of these compounds on BTI-Tn-5B 1-4 cell were also investigated for the insecticidal mechanism and found that quercetin represented superior inhibitory activity with MTT assay and reactive oxygen species （ROS） against BTI-Tn-5B 1-4 cell, but slightly weaker than that of the positive control （azadirachtin） and significantly greater than the negative control （DMSO only）. Meanwhile, eriodictyol demonstrated the strongest effect on the mitochondrial membrane potentials （MMP）. In conclusion, based on their comparative toxicities to commercial insecticides and their cytotoxic effects, some of the compounds from the F. sarmentosa have potential as botanical insecticides.

关键词： Ficus sarmentosa var. henryi Musca domestica Aedes albopictus insecticidal activity 7-hydroxycoumarin quercetin

Estimation of Chloride Diffusivity in Hydrated Tricalcium Silicate Using a Hydration-Diffusion Integrated Method

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 49-64页

作者： WANG Xin shen Dejian tao Sijie liU Ruixin WU shengxing College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China

This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S *** results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age.

关键词： tricalcium silicate simulation method chloride diffusion coefficient pore solution

Fine-tuning the spatial allocation of phytohormones for smart canopy, smart breeding, and smart agriculture

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Science China life Sciences 2025年第1期68卷 309-310页

作者： tao Zhou lin li National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University HuBei HongShan Laboratory

The dual challenges of global climate change and population growth have increased demand for higher crop yields per unit area. The innovative technology of smart agriculture aims to synergize breeding, cultivation, and production through the application of biological and informatics technologies. Historically, the “Green Revolution” introduced semidwarf varieties of certain key crops by utilizing mutations affecting gibberellin pathways, which significantly increased planting densities and yields.

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Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

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Science China Earth Sciences 2025年第1期68卷 62-73页

作者： Xin li Yibo ZHOU tao ZHAO Xingjian HE Yanhong PAN State Key Laboratory for Mineral Deposits Research Center for Critical Earth Material Cycling Centre for Research and Education on Biological Evolution and Environment and Frontiers Science School of Earth Sciences and Engineering Nanjing University Institute of Palaeontology Yunnan Key Laboratory of Earth System Science Yunnan Key Laboratory for PalaeobiologyYunnan University

Mammalian hair, as a key feature related to endothermy, physical protection, and camouflage, has a long geohistorical record that dates back even to the Mesozoic. However, the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time. To address this, we conducted taphonomic experiments to simulate the transformation process of black hair. The changes in the morphological structure, microscopic characteristics, and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy, Fourier transform infrared(FTIR) spectroscopy, and Raman spectroscopy. Our results revealed that damage to the morphology of hair began at a mild temperature(150–175°C), and hair transformed into a fluid-like mass at a relatively high temperature(200°C). In addition, the morphological structure of melanosomes had relatively greater preservation potential than keratins did, and the microscopic features of melanosomes were persistently stable. The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased. Although the chemical signals were not lost completely, the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200°C), whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable, even at high temperatures(>200°C). These results were confirmed by principal component analysis(PCA) and principal component analysis linear discriminant analysis(PCA–LDA). In addition, the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid), which suggested that Raman spectroscopy can be used to detect melanin in fossils.

关键词： Mammalian hair Melanin Keratin Fossilization Experimental taphonomy

Donor MHC gene to mitigate rejection of transplantation in recipient mice

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Chinese Medical Journal 2011年第24期124卷 4279-4285页

作者： li Tong YAN Jun TAN Jia-li LU Yue-ping HOU sheng-cai li shen-tao XU Qing TONG Xue-hong DING Jie ZHANG Zhi-tai li Hui Department of Thoracic Surgery Beijing Chao-Yang Hospital Capital Medical University Beijing 100020 China Department of Cardiae Surgery Beijing Chao-Yang Hospital Capital Medical University Beijing 100020 China Experimental Centre Beijing Chao-Yang Hospital Capital Medical University Beijing 100020 China Department of Orthodontics School of Stomatology FourthMilitary Medical University Xi＇an Shaanxi 710032 China Department of Molecular Biology Capital Medical University Beijing 100069 China Department of Thoracic Surgery Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

Background Donor organ rejection continues to be a significant problem for patients receiving transplants. We therefore tested whether transferring a donor＇s major histocompatibility complex （MHC） gene to the recipient would mitigate the rejection of transplanted hearts in mice. Methods H-2K^kgene from donor mice was amplified using nested polymerase chain reaction （PCR） and ligated into a mammalian expression vector, which was then transfected into thymus ground mass cells collected from the recipients. Clones stably expressing the transgene were then injected into the recipients＇ thymus visualized using ultrasound. Control mice were administered cells previously transfected with empty vector. Following heart transplantation, cardiac activity was monitored electrocardiographically. Recipient thymus cells were tested for MHC antigenicity using flow cytometry and spleen cells were subjected to mixed lymphocyte culture tests. Finally, the transplanted hearts were sectioned, stained and examined under light microscopy. Results Southern analysis following nested PCR revealed clear expression of H-2K^ gene. Following transplantation, electrocardiosignals were detectable highly significantly longer in recipients administered thymal cells expressing donor H-2K^ than in those receiving control cells. Flow cytometric analysis using an anti-H-2K^ antibody confirmed its expression in H-2K^ treated recipients but not in control mice. Mixed lymphocyte cultures containing H-2K^ treated cells showed significantly less proliferation than those containing control cells. Hearts from control mice showed substantially greater lymphocyte infiltration than those from H-2K^ treated mice and large areas of necrosis. Conclusion Rejection of transplanted hearts can be mitigated substantially by introducing the donor＇s MHC into the recipient.

关键词： major histocompatibility complex transplantation gene transference tolerance

Optimizing Fine-Tuning in Quantized Language Models:An In-Depth Analysis of Key Variables

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Computers, Materials & Continua 2025年第1期82卷 307-325页

作者： Ao shen Zhiquan Lai Dongsheng li Xiaoyu Hu National Key Laboratory of Parallel and Distributed Computing National University of Defense TechnologyChangsha410073China Strategic Assessments and Consultation Institute Academy of Military ScienceBeijing100091China

Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning *** this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader ***-Efficient Fine-Tuning(PEFT)techniques,such as Low-Rank Adaptation(LoRA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational *** these,QLoRA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLoRA *** these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains *** study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM *** investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do *** insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized ***,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller *** study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM

关键词： Large-scale Language Model Parameter-Efficient Fine-Tuning parameter quantization key variable trainable parameters experimental analysis

Synergistically enhanced ORR and HER performance on Co-N-C coupled in-situ generated PtCo intermetallic

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Journal of Energy Chemistry 2025年第1期100卷 721-729页

作者： Guanyu Luo Min Song Lulu An Xiao Huang Qian Zhang Chenhao Zhang tao shen Shuang Wang Deli Wang Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of Co atomic sites and in-situ generated PtCo intermetallic compounds （IMCs）(o-PtCo@CoNC) is proposed through Co pre-anchoring and subsequent impregnation-reduction *** loading of Co atoms provides a chance for in-situ generating PtCo ordered intermetallic *** remaining Co single atoms and PtCo IMCs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt Co IMCs and Co single atoms,o-PtCo@CoNC exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-PtCo@CoNC delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMCs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Synergistic effect Intermetallics Single atomic sites Oxygen reduction reaction Hydrogen evolution reaction

A Rapid Adaptation Approach for Dynamic Air‑Writing Recognition Using Wearable Wristbands with Self‑Supervised Contrastive Learning

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Nano-Micro Letters 2025年第2期17卷 417-431页

作者： Yunjian Guo Kunpeng li Wei Yue Nam‑Young Kim Yang li Guozhen shen Jong‑Chul Lee Department of Electronic Convergence Engineering Kwangwoon UniversitySeoul 01897South Korea Radio Frequency Integrated Circuit(RFIC)Bio Centre Kwangwoon UniversitySeoul 01897South Korea Department of Electronic Engineering Kwangwoon UniversitySeoul 01897South Korea School of Microelectronics Shandong UniversityJinan 250101People’s Republic of China State Key Laboratory of Integrated Chips and Systems Fudan UniversityShanghai 200433People’s Republic of China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081People’s Republic of China

Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily *** existing approaches that often focus on static gestures and require extensive labeled data,the proposed wearable wristband with selfsupervised contrastive learning excels at dynamic motion tracking and adapts rapidly across multiple *** features a four-channel sensing array composed of an ionic hydrogel with hierarchical microcone structures and ultrathin flexible electrodes,resulting in high-sensitivity capacitance *** wireless transmission from a Wi-Fi module,the proposed algorithm learns latent features from the unlabeled signals of random wrist ***,only few-shot labeled data are sufficient for fine-tuning the model,enabling rapid adaptation to various *** system achieves a high accuracy of 94.9%in different scenarios,including the prediction of eight-direction commands,and air-writing of all numbers and *** proposed method facilitates smooth transitions between multiple tasks without the need for modifying the structure or undergoing extensive task-specific *** utility has been further extended to enhance human–machine interaction over digital platforms,such as game controls,calculators,and three-language login systems,offering users a natural and intuitive way of communication.

关键词： Wearable wristband Self-supervised contrastive learning Dynamic gesture Air-writing Human-machine interaction

Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： Qiang liu Xiang li shen Du Ming Gao Yanbin Yin Jiongming Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity