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Precise Large Deviations for a Customer-based Individual Risk Model

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Acta Mathematicae Applicatae Sinica 2011年第2期27卷 209-222页

作者： xue-min Ma School of Mathematics and Statistics Wuhan University Wuhan 430072 China

In this paper, we propose a customer-based individual risk model, in which potential claims by customers are described as i.i.d, heavy-tailed random variables, but different insurance policy holders are allowed to have different probabilities to make actual claims. Some precise large deviation results for the prospectiveoss process are derived under certain mild assumptions, with emphasis on the case of heavy-tailed distribution function class ERV （extended regular variation）. Lundberg type limiting results on the finite time ruin probabilities are also investigated.

关键词： precise large deviations individual risk models (extended) regular variation finite time ruin probability

Classification and diagnosis of cervical lesions based on colposcopy images using deep fully convolutional networks: A man-machine comparison cohort study

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Fundamental Research 2025年第1期5卷 419-428页

作者： Dong, Binhua xue, Huifeng Li, Ye Li, Ping Chen, Jiancui Zhang, Tao Chen, Lihua Pan, Diling Liu, Peizhong Sun, Pengming Laboratory of Gynecologic Oncology Department of Gynecology Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics Fujian Medical University Fujian Fuzhou 350001 China Fujian Key Laboratory of Women and Children's Critical Diseases Research Fujian Fuzhou 350001 China Medical Center of Cervical Disease and Colposcopy Fujian Maternity and Child Health Hospital Fujian Fuzhou 350001 China Department of Gynecology and Obstetrics Quanzhou First Hospital Fujian Medical University Fujian Quanzhou 362000 China College of Computer Science and Technology Huaqiao University Fujian Xiamen 361021 China Department of Pathology Fujian Maternity and Child Health Hospital Fujian Fuzhou 350001 China College of Engineering Huaqiao University Fujian Quanzhou 362021 China School of Medicine Huaqiao University Fujian Quanzhou 362021 China

Colposcopy is an important technique in the diagnosis of cervical cancer. The development of computer-aided diagnosis methods can mitigate the shortage of colposcopists and improve the accuracy and efficiency of colposcopy examinations in China. This study proposes the Dense-U-Net model for colposcopy image recognition. This was a man–machine comparison cohort study. It presents a novel artificial intelligence (AI) model for the diagnosis of cervical lesions through colposcopy images using a Dense-U-Net image semantic segmentation algorithm. The Dense-U-Net model was created by applying the methods of “deepening the network structure,” “applying dropout” and “max pooling.” Moreover, image-based and population-based diagnostic performances of the AI algorithm and physicians with different levels of specialist experience were compared. In total, 2,475 participants were recruited, and 13,084 colposcopy images were included in this study. The diagnostic accuracy of the Dense-U-Net model increased significantly with increasing colposcopy images per patient. As the number of images in the training set increased, the diagnostic accuracy of the Dense-U-Net model for cervical intraepithelial neoplasm 3 or worse (CIN3+) diagnosis increased (P = 0.035). The rate of diagnostic accuracy (0.89 vs 0.85, P min, while the expert, senior, and junior colposcopists took 716.3 ± 49.76, 892.1 ± 92.30, and 3034.7 ± 259.51 min, respectively. The study

关键词： Auxiliary diagnosis Cervical lesions Colposcopic image Dense-U-Net Lesion segmentation

论政治勇气与政治话语表达——学习《中共中央关于进一步全面深化改革、推进中国式现代化的决定》

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山西师大学报（社会科学版） 2025年第1期52卷 1-7页

作者：荆学民王乐轩中国传媒大学政治传播研究所北京100024 中国传媒大学政府与公共事务学院北京100024

党的二十届三中全会通过的《中共中央关于进一步全面深化改革、推进中国式现代化的决定》,展现了中国共产党“伟大历史主动、巨大政治勇气、强烈责任担当”的精气神,表达了中国共产党“进一步全面深化改革、推进中国式现代化”的政治决... 详细信息

党的二十届三中全会通过的《中共中央关于进一步全面深化改革、推进中国式现代化的决定》,展现了中国共产党“伟大历史主动、巨大政治勇气、强烈责任担当”的精气神,表达了中国共产党“进一步全面深化改革、推进中国式现代化”的政治决心。其中,中国共产党的“政治勇气”成为一个亮点。政治勇气作为中国特色社会主义政治话语的集中表达,是与政治改革相匹配的、展现政治决心的、根植于政治实践的政治话语。在不同的历史阶段,我国的政治话语具有不同的侧重点,经历了从革命话语到改革话语的转型。随着党的政治勇气的提升,党的政治话语表达在政治目标上逐步具体、在政治信念上日益坚定、在政治底气上愈发充足。进入新时代,伴随中国共产党的政治勇气的提升,党的二十大提出“中国式现代化”,其话语内涵具有中国特色与世界意义的双重属性。“中国式现代化”作为政治话语表达的创新典范,不仅体现了中国对自身发展道路的政治自信,也彰显了中国愿与世界各国共享现代化建设经验的开放态度。在新的国际政治形势下,国际话语竞争日益激烈,为此可以采用话语框定、话语争论、话语叙事等话语博弈策略,进一步提升中国的国际政治话语权。

关键词：《中共中央关于进一步全面深化改革、推进中国式现代化的决定》政治勇气政治话语

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Effect of heat treatment on microstructure and mechanical properties of a novel Al-Zn-Mg-Cu alloy

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China Foundry 2025年

作者： Yan-mei Yang Xin-chen Tang Ye-fei Li xue-wei Fang Da-wei Yi Zhi-yun Zhang Qiao-ling Zheng Zhi-xi Wang Guo-yu Zhang Su Zhang Hao Cheng Yang He Yi-bo Liu Zi-han Wu Ya-nan Chen Yi-min Gao State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an Aerospace Precision Electromechanical Institute

Effects of solution and aging treatment on the microstructure and mechanical properties of a novel Al-Zn-Mg-Cu alloy by microalloying rare elements Sc and Er were studied. The results show that solution time has a visible influence on the microstructure and mechanical properties of the alloy. Specifically, as the solution time increases, the area fraction of the residual phase in the alloy decreases, and the shape of the grain becomes more spheroidal and coarser, leading to a decrease in hardness. This is attributed to the dissolution of strengthening phases during the solution treatment, which weakens the solid solution strengthening *** single-stage aging treatment shows an initial increase in strength and hardness of the alloy, followed by a decrease as the aging time is extended, until a steady state is achieved. The optimal single-aging conditions are found to be at 120 ℃ for 24 h, where the alloy exhibits an excellent combination of high strength and good ductility, with an ultimate tensile strength(UTS) of 523 MPa, yield strength(YS) of 482 MPa, and elongation(El)of 1.75%, respectively. Compared to single-stage aging, double-stage aging(120 ℃ for 24 h and then 150 ℃ for 52 h) significantly increases the elongation of the alloy(4.17%), but the UTS reduces to 465.29 MPa, and YS reduces to 410.64 MPa. Transmission electron microscopy(TEM) observations disclose that the grain size, the distribution spacing of precipitates along the grain boundary, and the width of the precipitation-free zone(PFZ) all undergo augmentation as the duration of the second stage aging process elongates.

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Synergistic effects of IL-3 release and Mn^(2+)-doped Prussian blue nanoparticles camouflaged with MES23.5 cell membranes on Alzheimer’s disease therapy

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Nano Research 2025年第2期18卷 594-606页

作者： Tuodi Zhang Zhonghui xue Qianqian He Junling Yang Ya Wen Xiaohui Lu min Xu Yuehua Guo Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityNantong 226001China

Alzheimer'sdisease(AD)isaprogressive neurodegenerative disorder with prolonged latency during the prodromal ***,current clinical approaches to pharmacological interventions for AD remain *** effective treatment strategy is to eliminate protein aggregates and prevent their *** this study,interleukin(IL)-3-loaded porous manganese(Mn^(2+))-doped Prussian blue(PB)nanoparticles(NPs)were coated with dopaminergic MEs23.5 neuronal cell membranes(PBMn-IL3@CM)and then used to combat AD *** PBMn-IL3@CM NPs possessed a high targeting efficiency,being able to traverse the blood-brain barrier and specifically affect the brain to reduce oxidative *** Mn2-doped PB NPs effectively scavenged reactive oxygen radicals produced by microglia,inducing the pro-inflammatory M1 *** addition,the released IL-3 activated microglia,causing the polarization of the M1 phenotype to the anti-inflammatory M2 phenotype in vitro and in *** transition reduced phosphorylated tau accumulation,mediated neurotoxicity,and eliminated tau aggregates,which reversed cognitive impairment in AD *** PBMn-IL3@CM NPs showed excellent biocompatibility without significant adverse effects;consequently,they represent a promising AD treatment.

关键词： Alzheimer's disease neuroinflammation brain-targeted drug delivery tau neuropathology reactive oxygen species

DISTRIBUTION OF LEAD IN URBAN SOIL AND ITS POTENTIAL RISK IN SHENYANG CITY, CHINA

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Chinese Geographical Science 2006年第2期16卷 127-132页

作者： WANG Jin-da ren Hui-min LIU Jing-shuang YU Jun-bao ZHANG xue-lin Northeast Institute of Geography and A groecology Chinese Academy of Sciences Changchun 130012 P. R. China Graduate School of Chinese Academy of Sciences Beijing 100049 P. R. China

The horizontal and vertical distribution characteristics of Pb in urban soil of Shenyang City, China were investigated in this study. The range of Pb concentration in the soil was 22.02-2910.60mg/kg. The standard deviation was 443.07mg/kg, and coefficient of variation was 1.64. Tiexi District was seriously contaminated by lead. In general, Pb concentration in the soil decreased with distance from pollution source. Lead concentration varied in different functional areas with the order of industrial area>commercial area>residential area>suburb>reference area. Pb concentration decreased with the depth of soil profile. Both geo-accumulation index and ecological risk index were used to estimate the potential risk of soil Pb pollution in Shenyang City. The results showed that the high potential risk area included Tiexi District and traffic roads.

关键词： Pb in soil Pb distribution potential risk Shenyang City

High-pressure microwave-assisted synthesis of WS_(x)/Ni_(9)S_(8)/NF hetero-catalyst for efficient oxygen evolution reaction

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Rare Metals 2021年第5期40卷 1048-1055页

作者： xue Ma Xin-Yu Zhang min Yang Jing-Yi Xie ren-Qing Lv Yong-ming Chai Bin Dong College of Science China University of Petroleum(East China)Qingdao 266580China State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao 266580China

Designing the specific crystal phase with better intrinsic activity and more active sites is a very promising strategy for earth-abundant electrocatalysts for oxygen evolution reaction(OER).Herein,a facile two-step method including the high-pressure microwave and the hydrothermal sulfurization is adopted to prepare the WS_(x)/Ni_(9)S_(8) hetero-catalyst on nickel foam(WS_(x)/Ni_(9)S_(8)/NF).Firstly,WO3 polyhedrons homogeneously cover the surface of NF through the high-pressure microwave hydrothermal ***,WS_(x)/Ni_(9)S_(8) nanoparticles on the surface of NF can be synthesized after a hydrothermal sulfurization,which has been confirmed by scanning electron microscopy(SEM) elemental mapping and high-resolution transmission electron microscopy(HRTEM).The amorphous WSx and Ni9 S8 phase may provide the dual active sites for *** electrochemical measurements show that WS_(x)/Ni_(9)S_(8)/NF has superior OER activity with a low overpotential of 320 mV at the current density of 100 mA·cm^(-2),better than those of other *** enhanced OER performance may be due to the synergistic catalysis from Ni9 S8 phase and high valence of *** to the stable structure of Ni9 S8,the long-term stability of WS_(x)/Ni_(9)S_(8)/NF for at least 10 h can be *** work may provide a new approach for the doped nickel sulfides crystal phase through high-pressure microwave hydrothermal assistance for OER.

关键词： Amorphous WS_(x) Ni_(9)S_(8) High-pressure microwave hydrothermal Electrocatalyst Oxygen evolution reaction

Theoretical Investigation on the Luminescent Properties of Polyfluorene and Poly(fluorene-co-thiophene)

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Chemical Research in Chinese Universities 2009年第5期25卷 711-718页

作者： FENG Ji-kang ZHANG Jing-hua ren Ai-min RAN xue-qin LI Yuan-yuan State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry College of Chemistry Jilin University Changchun 130021 P. R. China

The density functional theory was employed to study the structures, ionization potentials（IPs）, electron affinities（EAs）, and HOMO-LUMO gaps（ΔH-L） of the oligomers. The time-dependent density functional theory（TD-DFT） and ZINDO were employed to study the lowest excitation energies（Egs） and the absorption and emission spectra of the oligomers of polyfluorene（PF） and poly（fluorene-co-thiophene）（PFT）. By extrapolating ΔH-L and Egs to those of infinite chain length, band gaps and effective conjugation lengths of the corresponding polymers were obtained. The IPs, EAs and 2abs of the polymers were obtained by extrapolating those of the oligomers to the inverse chain length equal to zero（I/n=0）. The outcome shows the decreased dihedral angle between fluorene and thiophene units in the PFT compared to that between fluorene units in the PF results in the increased efficient conjugation of PFT. These cause both the maximal absorption and emission wavelengths of PFT red-shifted compared with those of PF.

关键词： Polyfluorene Poly(fluorene-co-thiophene) Luminescent property

Phase-Field Simulation of Sintering Process:A Review

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1165-1204页

作者： ming xue min Yi State Key Laboratory ofMechanics and Control forAerospace Structures&Institute for Frontier Science&Key Laboratory for Intelligent Nano Materials and Devices of ministry of Education&College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics(NUAA)Nanjing210016China

Sintering,a well-established technique in powder metallurgy,plays a critical role in the processing of high melting point materials.A comprehensive understanding of structural changes during the sintering process is essential for effective product *** phase-field method stands out for its unique ability to simulate these structural *** its widespread application,there is a notable absence of literature reviews focused on its usage in sintering ***,this paper addresses this gap by reviewing the latest advancements in phase-field sintering models,covering approaches based on energy,grand potential,and entropy *** characteristics of various models are extensively discussed,with a specific emphasis on energy-based models incorporating considerations such as interface energy anisotropy,tensor-form diffusion mechanisms,and various forms of rigid particle motion during ***,the paper offers a concise summary of phase-field sintering models that integrate with other physical fields,including stress/strain fields,viscous flow,temperature field,and external electric *** conclusion,the paper provides a succinct overview of the entire content and delineates potential avenues for future research.

关键词： Phase-field model review sintering additive manufacturing