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Distinct Mechanisms Governing Two Types of Extreme Hourly Rainfall Rates in the Mountain Foothills of North China During the Passage of a Typhoon Remnant Vortex from 30 July to 1 August 2023

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Advances in Atmospheric Sciences 2025年第4期 761-779页

作者： Rudi xia Yuqing RUAN Jisong SUN Xudong LIANG Chong WU Feng LI Ju LI Jinfang yin Xinghua BAO Mingxin LI xiaoyu GAO State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Institute of Urban Meteorology China Meteorological Administration Research Center for Disastrous Weather over Hengduan Mountains & Low-Latitude Plateau China Meteorological Administration

This study investigates extreme rainfall episodes along the eastern foothills of the Taihang Mountains in North China from 30 July to 1 August 2023. It focuses on two types of extreme hourly rainfall rates(HRRs), i.e., the maximum regional-average HRR and site-observed HRR, which exhibited sequential development over southern, middle, and northern key regions. These rainfall extremes occurred in an environment where a high-pressure barrier over North China prevented the intrusion of cold air masses from the north while a northward-moving typhoon remnant vortex and its associated low-level jet(LLJ) transported warm and moist airflow from the south. Two distinct echo evolution modes and convection initiation mechanisms are identified for the two types of extreme HRRs. The maximum regional-average HRR occurred when the LLJ arrived to the east of the key regions, while the maximum site-observed HRR occurred when the warmer vortex center influenced the regions. Taking the northern key region as a representation, at the time of the maximum regional-average HRR, slantwise ascent of the airflow along a warm-frontal-like boundary released energy related to symmetrical instability,resulting in stratiform rainfall with weak convective cores. The transport of locally initiated convection over the eastern plain region, where the atmospheric stratification was more potentially unstable, also significantly contributed. When the maximum site-observed HRR occurred, the terrain lifting of warm and moist southeast airflow led to intense convection over the mountain foothills. Overall, the passage of the warm-core typhoon remnant vortex and interaction with Taihang Mountains determined the timing and location of extreme HRRs across the key regions.

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胸主动脉无裸区覆膜支架治疗蓬松降主动脉瘤1例

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中国介入影像与治疗学 2025年第2期22卷 151-152页

作者：刘茜尹洪彬夏文华李宗勋安君延边大学附属医院(延边医院)心血管外科二吉林延吉133000

患者男,72岁,无明显诱因出现胸部撕裂样疼痛5 h,无头晕、头痛;既往罹患高血压13年,未规律用药,血压控制不佳。查体:神志清,痛苦貌,心率82次/分,血压160/109 mmHg,双肺清,未闻及心脏杂音。实验室检查无特殊。主动脉CT血管成像(computed t... 详细信息

患者男,72岁,无明显诱因出现胸部撕裂样疼痛5 h,无头晕、头痛;既往罹患高血压13年,未规律用药,血压控制不佳。查体:神志清,痛苦貌,心率82次/分,血压160/109 mmHg,双肺清,未闻及心脏杂音。实验室检查无特殊。主动脉CT血管成像(computed tomographic angiography,CTA):降主动脉呈蓬松主动脉(shaggy aorta,SA)样改变,见弥漫性动脉粥样硬化伴多发溃疡及附壁血栓,形成蓬松降主动脉瘤并见壁间血肿;左椎动脉起源于主动脉弓(图1A、1B)。影像学诊断:蓬松降主动脉瘤合并壁间血肿。以胸主动脉无裸区覆膜支架行主动脉腔内隔绝术。

关键词：主动脉瘤,胸支架介入治疗

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Effect of Nd-Ho-Al-Ga diffusion on coercivity and thermal stability of hot-deformed PrNd-Fe-B magnets

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Journal of Rare Earths 2025年第3期 578-583页

作者： Yuhang Cui Xu Tang Renjie Chen Yeyuan Du Ge Dai Yong Ouyang Yiping Huang Wenzong yin Jinyun Ju xianshuang xia Aru Yan School of Materials Science and Chemical Engineering Ningbo University CISRI&NIMTE Joint Innovation Center for Rare Earth Permanent Magnets Ningbo Institute of Material Technology and EngineeringChinese Academy of Sciences University of Chinese Academy of Sciences

In this study,to enhance the coercivity and high-temperature stability of hot-deformed PrNd-Fe-B magnets,the NdHoAlGa alloy was utilized as a diffusion source and a dual-alloy diffusion process was employed to enhance the room temperature coercivity from 1.72 to 2.28 *** the magnet doped with7 wt% Nd72.3Ho13.8Al2.3Ga11.7,within the temperature range from 20 to 200℃,the remanence temperature coefficient a increases from-0.16%/℃ to-0.14%/℃,and the coercivity temperature coefficient βincreases from-0.49%/℃ to-0.43%/℃.By controlling grain boundary（GB） phases and optimizing the main phase simultaneously,Ga was induced to motivate the formation of non-ferromagnetic GB phases,reducing the size of grains and intergranular exchange ***,Ho was diffused into the main phase,forming（Pr,Nd,Ho）-Fe-B phase,which enhances the magnetic crystalline anisotropy field of the main phase grains at high temperatures.

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A Commutation Failure Prediction and Mitigation Method

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Journal of Modern Power Systems and Clean Energy 2022年第3期10卷 779-787页

作者： Renlong Zhu xiaoping Zhou Haitao xia Lerong Hong Hanhang yin College of Electrical and Information Engineering Hunan UniversityChangsha 410082China

The mitigation of commutation failure(CF)depends on the accuracy of CF *** terms of the large error of the existing extinction angle(EA)calculation during the fault transient period,a method for CF prediction and mitigation is *** in both DC current and overlap angle(OA)are considered in the proposed method to predict the EA *** addition,variations in critical EA and the effect of firing angle(FA)on both DC current and OA are considered in the proposed method to obtain the accurate FA order for the control *** proposed method can achieve good performance in terms of CF mitigation and reduce reactive consumption at the inverter side when a fault *** results based on the PSCAD/EMTDC show that the proposed method predicts CF rapidly and exhibits good performance in terms of CF mitigation.

关键词： Commutation failure prediction commutation failure mitigation line commutated converter based high-voltage direct current(LCC-HVDC) extinction angle(EA) overlap angle(OA) firing angle(FA)

Engineering W/O/W pickering emulsion for the enhanced antigen delivery and immune responses

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Particuology 2024年第9期92卷 224-233页

作者： Sihua Wu xiaonan Huang yin Ma Naoki Asakawa Yufei xia State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100081China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese Academy of SciencesBeijing100190China Division of Molecular Science Graduate School of Science and TechnologyGunma University1-5-1Tenjin-choKiryu376-8515Japan Sinovac Biotech Ltd. Beijing100085China School of Chemical Engineering Nanjing Tech UniversityNanjing211816China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

Tumor immunotherapy,particularly cancer vaccines,holds promise for combating cancer by harnessing tailored immune responses against malignant ***,conventional approaches face challenges in efficiently delivering antigens for optimal immune *** adjuvants,like MF59,enhance cellular uptake but struggle to induce robust CD8^(+)T cell ***,we introduce a novel strategy employing a water-in-oil-in-water(W/O/W)multiple Pickering emulsion(mPE)for antigen *** mPE,utilizing biocompatible,pH-sensitive particles,encapsulates antigens within the inner water phase,ensuring enhanced intracellular processing and dictating the intracellular fate of antigens for improved *** vitro and in vivo studies demonstrated that mPEs induced robust dendritic cells activation and antigen cross-presentation,leading to a significantly enhanced immune ***,calcium phosphate-stabilized mPE(CaP-mPE)illustrated the more robust IFN-γ^(+)T cell *** comparison with traditional surfactant-stabilized multiple emulsions,CaP-mPE significantly inhibit tumor growth and effectively prolong the survival of tumor-bearing *** innovative approach offers a promising avenue for the development of effective cancer vaccines with potent cellular immune responses.

关键词： Cancer vaccine Multiple pickeringemulsion Adjuvant Antigen delivery Anti-tumor response

智能时代的红树林知识服务展望:从植物图谱到知识图谱

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中国科学:地球科学 2025年第1期55卷 111-125页

作者：侯志伟荆文龙秦承志杨骥夏清尹小玲广东省科学院广州地理研究所广东省遥感与地理信息系统应用重点实验室广东省地理时空大数据工程实验室广州510070 南方海洋科学与工程广东省实验室(广州) 广州511458 中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101 中国科学院大学资源与环境学院北京100049 长沙理工大学交通运输工程学院长沙410114

红树林关乎地球生态安全和人类福祉,其管理、保护与修复离不开生物、生态等多学科领域知识与时空信息的支撑.植物图谱等传统知识服务可以提供图文并茂的红树林知识.然而,这种面向信息检索的服务方式,无法有效挖掘和利用多源异构数据中... 详细信息

红树林关乎地球生态安全和人类福祉,其管理、保护与修复离不开生物、生态等多学科领域知识与时空信息的支撑.植物图谱等传统知识服务可以提供图文并茂的红树林知识.然而,这种面向信息检索的服务方式,无法有效挖掘和利用多源异构数据中的碎片化知识,面临“数据海量、知识难求”困境.知识图谱可将海量数据中蕴含的知识,提取、组织、融合为计算机可理解、可计算的语义网络,为实现智能知识服务提供了解决方案.本文聚焦红树林知识获取、形式化表达及智能服务的迫切需求,提出了红树林知识图谱和知识服务构想.首先分析了不同领域图谱概念的异同,认为红树林知识图谱是以红树林生态系统为核心,融合了多领域知识和时空信息的大规模知识库;然后提出了红树林知识服务的研究框架,该框架可实现多模态数据到智能知识服务的转变,包括泛在数据感知与汇聚、知识组织与图谱构建、智能知识服务等多个层次;接着重点介绍了红树林知识图谱的构建方法与流程;最后探讨了目前红树林知识服务面临的挑战,提出在人工智能时代,构建融合领域特色与时空特征的红树林知识体系,探索大模型支持下的知识抽取与融合方法,并研发面向典型场景的智能知识应用,是红树林知识服务的主要发展方向.

关键词：红树林图谱知识图谱多模态知识服务

益气养阴解毒方对Lewis肺癌小鼠的免疫调节及抗肿瘤作用

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南京中医药大学学报 2025年第1期41卷 95-101页

作者：刘莲芳卢子涵胡霞周勤峰秦垠梅宇波南京中医药大学附属张家港医院江苏张家港215600 南京中医药大学中西医结合学院江苏南京210023

目的探索益气养阴解毒方对Lewis肺癌小鼠的抗肿瘤作用及其对免疫调节的影响。方法腋下皮下注射Lewis肺癌细胞构建Lewis肺癌小鼠模型,分为模型组、低剂量组、中剂量组、高剂量组,并计算肿瘤体积、抑瘤率和生存率。分别使用HE染色,TUNEL... 详细信息

目的探索益气养阴解毒方对Lewis肺癌小鼠的抗肿瘤作用及其对免疫调节的影响。方法腋下皮下注射Lewis肺癌细胞构建Lewis肺癌小鼠模型,分为模型组、低剂量组、中剂量组、高剂量组,并计算肿瘤体积、抑瘤率和生存率。分别使用HE染色,TUNEL试验和彗星实验检测肿瘤细胞凋亡和DNA损伤。ELISA法检测IFN-γ、IL-2、TNF-α的表达水平。免疫荧光、流式细胞术检测CD8^(+)T、CD8^(+)/CD4^(+)T、PD-1^(+)、IFN-γ^(+)、CD28^(+)细胞占比。Western blot法检测PD-1、CD69、CD28的蛋白水平。结果益气养阴解毒方具有抗肿瘤,延长生存期的作用,还可促进肿瘤细胞凋亡并加剧肿瘤细胞DNA损伤。益气养阴解毒方促进了IFN-γ、IL-2、TNF-α的表达,提高了CD8^(+)T、CD8^(+)/CD4^(+)T、IFN-γ^(+)、CD28^(+)细胞占比,并抑制了PD-1^(+)细胞占比和蛋白表达,CD69、CD28的蛋白水平显著上升。结论益气养阴解毒方可以抑制肿瘤发展,其对免疫功能的调节是其抗肿瘤作用的潜在作用机制。

关键词：益气养阴解毒方非小细胞肺癌免疫调节 PD-1

Study on the model of an insurer's solvency ratio in Markov-modulated Brownian markets

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Applied Mathematics(A Journal of Chinese Universities) 2011年第1期26卷 23-28页

作者： xia Deng-feng FEI Wei-yin LIANG Yong School of Mathematics and Physics Anhui Polytechnic University Wuhu 241000 China

In this paper the insurer＇s solvency ratio model with or without jump diffusion process in the presence of financial distress cost is constructed, where an insurer＇s solvency ratio is characterized by a Markov-modulated dynamics. By Girsanov＇s theorem and the option pricing formula, the expected present value of shareholders＇ terminal payoff is provided.

关键词： Markov-modulated market jump diffusion process solvency ratio Girsanov's theorem financialdistress cost.

The EM algorithm for ML Estimators under nonlinear inequalities restrictions on the parameters

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Applied Mathematics(A Journal of Chinese Universities) 2019年第4期34卷 393-402页

作者： SHEN Qi-xia MIAO Peng LIANG yin-shuang Department of Basic Course Zhengzhou University of Science and TechnologyZhengzhou 450064China Information Engineering School of Zhengzhou Institute of Technology Zhengzhou 450044China

One of the most powerful algorithms for obtaining maximum likelihood estimates for many incomplete-data problems is the EM ***,when the parameters satisfy a set of nonlinear restrictions,It is difficult to apply the EM algorithm *** this paper,we propose an asymptotic maximum likelihood estimation procedure under a set of nonlinear inequalities restrictions on the parameters,in which the EM algorithm can be *** this kind of estimation problem is a stochastic optimization problem in the *** make use of methods in stochastic optimization to overcome the difficulty caused by nonlinearity in the given constraints.

关键词： Linear regression Maximum likelihood estimation Nonlinear constraints Asymptotic properties