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Electromagnetic Scattering by a Chiral Grating in a Homogeneous Chiral Environment and its Finite Element Method with Perfectly matched Absorbing Layers

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Numerical mathematics A Journal of Chinese Universities(English Series) 2006年第2期15卷 164-179页

作者： deyue Zhang Fuming ma School of mathematics Jilin University Changchun 130012 China School of Computer Science and Technology Jilin University Changchun 130012 China

The scattering of time-harmonic electromagnetic waves propagating in a homo- geneous chiral environment by a chiral grating is studied. The problem is simplified to a two-dimensional scattering problem, and the existence and the uniqueness of solutions are discussed by a variational approach. The di?raction problem is solved by a finite element method with perfectly matched absorbing layers. Our computational experiments indicate that the method is e?cient.

关键词：手性介质麦克斯韦方程组完全匹配层电磁波散射

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Reversing anther thermotolerance by manipulating the cis-elements in the promoter of a high-temperature upregulated gene Casein Kinase I in upland cotton

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Science China Life Sciences 2025年

作者： Yanlong Li Yinuo Fu Yaoyao Li Rui Zhang Jing Yang Huanhuan ma Ling Min Xianlong Zhang National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University

High temperature (HT) stress causes male sterility,leading to reduced upland cotton ***,we identified a key gene,Casein Kinase I (GhCKI),that negatively regulates male fertility in upland cotton under ***,conventional genetic manipulations of GhCKI would result in male sterility,hindering its utilization in breeding ***,we engineered quantitative variation for anther thermotolerance-related traits in upland cotton by creating weak promoter alleles of GhCKI genes,using CRISPR/Cas9 and CRISPR/Cpf1genome ***,we screened and identified two new upland cotton plant lines exhibiting a HT-tolerant phenotype with edited GhCKI promoters,and characterized their corresponding heat-tolerant allelic *** research revealed that the primary reason for the HT tolerance of the GhCKI promoter editing mutants is that the trans-acting factors GhMYB73 and GhMYB4,which positively regulate GhCKI expression under HT,failed to bind and activate the expression of ***,our study not only provides a rapid strategy to generate new beneficial alleles but also offers novel germplasm resources and molecular insights for crop HT tolerance breeding.

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数字普惠金融的农户增收效应与作用机制——基于陕西省9市18县的调查数据

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西北农林科技大学学报（社会科学版） 2025年第1期25卷 101-110页

作者：马红刚西安交通大学经济与金融学院西安710049

拓展农民增收致富渠道是完善城乡融合发展体制机制的关键环节,也是中国实现共同富裕的核心目标。基于陕西省9市18县(区)3658份农户微观调研数据,运用逻辑回归模型与中介效应模型,分析了数字普惠金融对农户家庭收入的影响及其作用机制。... 详细信息

拓展农民增收致富渠道是完善城乡融合发展体制机制的关键环节,也是中国实现共同富裕的核心目标。基于陕西省9市18县(区)3658份农户微观调研数据,运用逻辑回归模型与中介效应模型,分析了数字普惠金融对农户家庭收入的影响及其作用机制。研究表明,数字普惠金融对农户家庭收入具有显著的正向影响,数字普惠金融发展水平越高的县域,农户的家庭收入水平越高,特别是在数字普惠金融的使用深度、覆盖广度与数字化程度方面,影响尤为显著。进一步探讨作用机制后发现,缓解家庭金融约束、促进信息对称与扩大农业经营规模是数字普惠金融促进农户增收的主要途径。此外,数字普惠金融的增收效应存在异质性,农村居民的金融素养与金融市场参与度越高,数字普惠金融对农户家庭收入的正向影响越显著。

关键词：数字普惠金融农户增收信息获取农业经营规模信贷约束

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： Jun Jiang Zhenjie Lu Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu Zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 ma cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Ductility

Design high-performance narrowband emitters for blue light-emitting diodes through manipulating resonance structure of aromatic heterocycles

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Science China Chemistry 2025年

作者： Yue Yu Lei Xu Wenle Tan Yuyu Pan Jiyin Xiao Bohan Wang Guangjun Tian Yuguang ma Lei Ying Institute of Polymer Optoelectronic materials and Devices Guangdong Basic Research Center of Excellence for Energy and Information Polymer Materials State Key Laboratory of Luminescent Materials and Devices South China University of Technology School of Petrochemical Engineering Shenyang University of Technology Key Laboratory for Microstructural material Physics of Hebei Province School of Science Yanshan University

Narrowband light-emitting materials play critical roles in improving the color gamut and energy consumption of electroluminescence. Herein we demonstrated that by regulating the ground state resonance structure form of emitters with polycyclic aromatic heterocycles, the high-energy vibration of the C–C bond can be effectively suppressed, resulting in narrow emission like classical cyanine dyes. The designed compounds consist of twist and planar conformation, while having differences in the orientation of the positioning electron-donating(nitrogen) and electron-accepting(carbonyl) groups in the polycyclic aromatic hydrocarbon skeleton. The resulting compound Ac-Ph-Ac with a dominated zwitterionic resonance structure exhibits a relatively wide electroluminescent profile with the full width at half maximum(FWHM) of 42 nm and moderate device performance. In contrast, the “soliton transition” of 2AcPh based on the cyanine limit character effectively suppresses C–C stretching vibration in the polycyclic aromatic heterocycle skeleton, leading to a narrow electroluminescent profile with FWHM of 30 nm(0.16 eV)associated with an impressively high external quantum efficiency of 28.52%, which is among the highest efficiencies of so far reported non-sensitized organic light-emitting diodes.

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Voxel event graph neural network for event-based human gait recognition

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Optoelectronics Letters 2025年

作者： ma Guangyuan GONG Xiaolin XU Jiangtao GAO Jiandong GUO Zhaoxuan School of Microelectronics， Tianjin University

To improve the accuracy of event-based gait recognition， a method called voxel event graph neural network (VEGNN) is proposed. This method voxelizes the event stream and selects representative voxels as vertices of the graph. Then the edges are constructed based on spatio-temporal distance and temporal order constraints so that the event stream is constructed as a graph structure. Finally， a lightweight feature extraction network based on graph neural networks (GNNs) is used to efficiently capture spatio-temporal information and motion cues from the event graph. To evaluate our method， an event-based gait recognition dataset called Celex-Gait is created. Experimental results show that VEGNN achieves a gait recognition accuracy of 95.8% (best among all methods) and 93.9% (second best among all methods) on the Celex-Gait dataset and the DVS128-Gait-Day dataset， respectively. Furthermore， compared to the state-of-the-art methods， VEGNN reduces the number of model parameters by 30%. This indicates that VEGNN achieves higher recognition accuracy with lower model complexity.

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Rational design of lipid-activatable NIR-II probes for precisely imaging atherosclerotic plaque

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Science China Chemistry 2025年

作者： Xinyu Xu Yuan ma Hui Cao Li Xu Haoming Chen Sulai Liu Wei Sun Guosheng Song Xiaobing Zhang State Key Laboratory for Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan University Department of Hepatobiliary Surgery/Central Laboratory Hunan Provincial People's Hospital (The First Affiliated Hospital of Hunan Normal University) Department of Cardiology the First Affiliated Hospital of Nanjing Medical University Key Laboratory of Targeted Intervention of Cardiovascular Disease Collaborative Innovation Center for Cardiovascular Disease Translational MedicineNanjing Medical University Shenzhen Research Institute of Hunan University

Atherosclerosis(AS) is a prevalent condition associated with cardiovascular and cerebrovascular diseases, featuring lipid-laden plaque; however, the insufficient resolution and low sensitivity of traditional medical imaging techniques limit their application in lipid imaging. Currently, the second near-infrared(NIR-II) fluorescence imaging offers promising sensitivity and convenience. However, existing probes have limitations in terms of signal-to-background ratio, penetration depth, and tissue scattering. Herein, we use a molecular regulatory strategy to design a lipid-activatable probe Rh-965 with high specificity and NIR-II emission for improved imaging potential in deep tissues. The potential of Rh-965 for imaging plaque lipids in mice with AS is demonstrated by localizing carotid artery plaques using NIR-II imaging. The development of more stable lipid-activated NIR-II probes can significantly enhance atherosclerosis diagnosis and facilitate in vivo imaging in deeper tissues.

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Self-assembled carbon monoxide nanoprodrug for chemiexcitationtriggered synergistic chemotherapy against breast cancer

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Science China Chemistry 2025年

作者： Shunfei Cui Yiyao Pan Chenzhe ma Bin Qi Qingqiang Min Ming Li Huabing Chen Hengte Ke Xingyue Ji Jiangsu Province Engineering Research Center of Precision Diagnostics and Therapeutics Development College of Pharmaceutical ScienceSoochow University

Carbon monoxide（CO） has recently been well-established as a promising therapeutic modality against cancer. The development of transition-metal-free and tumor-targeted delivery platforms for CO is highly demanded but remains very sporadic. Herein, we developed a polyprodrug system for the co-delivery of CO and a chemotherapeutic agent combretastin A-4（CA-4） to the tumor site based on a chemiexcitation mechanism. Such a poly-prodrug successfully achieved the co-activation of CO and CA-4 in response to H2O2at the tumor site both in vitro and in vivo. Importantly, a synergist effect between CO and CA-4 was observed in suppressing tumor growth in a mouse tumor model. It is anticipated that such a poly-prodrug system could be potentially adapted for the co-delivery of CO and another drug payload for combinational therapy for other indications.

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Catalytic atroposelective synthesis of indolyl quinazolinones bearing N-N/C-C diaxes

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Science China Chemistry 2025年

作者： Ning-Yi Wang Shuo Gao Zhu-Di Shu Bei-Bei Cheng Chun ma Yu-Chen Zhang Feng Shi Research Center of Chiral Functional Heterocycles School of Chemistry and Materials Science Jiangsu Normal University School of Petrochemical Engineering Changzhou University School of Chemistry and Chemical Engineering Henan Normal University

The first catalytic atroposelective synthesis of indole derivatives bearing N-N/C-C diaxes has been established by the strategy of de novo ring formation. By this strategy, various indolyl quinazolinones bearing vicinal N-N/C-C diaxes were synthesized in high yields with overall good diastereoselectivities and excellent enantioselectivities via chiral phosphoric acid-catalyzed onepot asymmetric formal (5+1) cycloaddition/oxidation reaction. Moreover, such indolyl quinazolinones bearing vicinal N-N/CC diaxes have good configurational stability and could be converted into new chiral ligands with applications in asymmetric catalysis. Therefore, this work not only offered a new member for the family of diaxial atropisomers, but also provided a powerful strategy for catalytic asymmetric synthesis of atropisomers bearing N-N/C-C diaxes.

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