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具有Markov切换脉冲随机时滞系统的有限时间稳定

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安徽工业大学学报（自然科学版） 2024年第2期41卷 182-188页

作者：尹浩姚凤麒王国庆安徽工业大学电气与信息工程学院安徽马鞍山243032

针对一类具有Markov切换和时变时滞脉冲随机系统,利用Lyapunov–Krasovskii(L–K)泛函法和平均脉冲区间条件建立系统均方有限时间稳定的相关性准则。利用广义伊藤公式求出L–K泛函关于时间的导数,根据积分不等式对求出的L–K泛函导数进... 详细信息

针对一类具有Markov切换和时变时滞脉冲随机系统,利用Lyapunov–Krasovskii(L–K)泛函法和平均脉冲区间条件建立系统均方有限时间稳定的相关性准则。利用广义伊藤公式求出L–K泛函关于时间的导数,根据积分不等式对求出的L–K泛函导数进行放缩,降低判据的保守性;结合平均脉冲区间条件约束均匀时间间隔内脉冲发生次数,得到以线性矩阵不等式(LMI)形式的时滞相关稳定性判据,进一步降低判据的保守性;设计使系统满足有限时间稳定的状态反馈控制器,且给出实例进行验证。结果表明:本文建立的相关性准则,通过选取模态相关的泛函且利用平均脉冲区间条件,可进一步降低判据的保守性。

关键词： Markov切换脉冲随机时滞系统有限时间稳定平均脉冲区间线性矩阵不等式

Aquatic fungal diversity in two freshwater ecosystems of Madhya Pradesh,India

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Studies in Fungi 2021年第1期6卷 116-137页

作者： Mehboob A Ganie ah Dar AR Soni KK Rani Durgawati Vishwavidyalaya Jabalpur M.P-India Departments of Botany University of KashmirKargil CampusIndia Govt Degree College Bemina J&K-India Forest Pathology Division Tropical Forest Research Institute Jabalpur M.P-India

Aquatic fungi play an important role in litter decomposition in aquatic *** in view the importance of aquatic fungi,diversity of these organisms was studied in two freshwater ecosystems of Gaur River and Khurji Nala Jabalpur Madhya Pradesh *** the present study,34 fungal species and 6 chromista species have been recorded on decomposing *** number of fungal genera were recorded in submerged litter samples of Tectona grandis followed by Dendroclamus *** maximum percentage frequencies of various fungal species which colonize litter of different tree species were also *** cluster analysis revealed that different fungal communities on various plant hosts vary significantly.

关键词： Colonization decomposing substrate fruits litter mixed twigs

Bismuth nanorods confined in hollow carbon structures for high performance sodium-and potassium-ion batteries

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Journal of Energy Chemistry 2022年第4期31卷 787-796页

作者： Hongli Long Xiuping yin Xuan Wang Yufeng Zhao Liuming Yan College of Sciences&Institute for Sustainable Energy Shanghai UniversityShanghai 200444China

Bismuth has drawn widespread attention as a prospective alloying-type anode for sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs)due to its large volumetric ***,such material encounters drastic particle pulverization and overgrowth of solid-electrolyte interphase(SEI)upon repeated(de)alloying,thus causing poor rate and cycling ***,we report a unique structure design with bismuth nanorods confined in hollow N,S-codoped carbon nanotubes(Bi@NS-C)fabricated by a solvothermal method and in-situ thermal ***-situ SEM observations confirm that such a design can significantly suppress the size fining of Bi nanorods,thus inhibiting the particle pulverization and repeated SEI growth upon charging/*** as achieved Bi@NS-C demonstrates outstanding rate capability for SIBs(96.5%capacity retention at 30 A g^(-1) vs.1 A g^(-1)),and a record high rate performance for PIBs(399.5 m ah g^(-1)@20 A g^(-1)).Notably,the as constructed full cell(Na_(3)V_(2)(PO_(4))_(3)@C|Bi@NS-C)demonstrates impressive performance with a high energy density of 219.8 W h kg^(-1) and a high-power density of 6443.3 W kg^(-1)(based on the total mass of active materials on both electrodes),outperforming the state-of-the-art literature.

关键词： Bismuth anode Hollow structure Composites High rate performance Sodium-and potassium-ion batteries

时变风险厌恶与人民币汇率波动率--基于GARCH-MIDAS-SK模型的实证研究

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数理统计与管理 2024年第4期43卷 721-736页

作者：吴鑫育梅学婷周海林尹学宝安徽财经大学金融学院安徽蚌埠233030

经验研究表明汇率收益率分布呈现出时变高阶矩(偏度和峰度)特征,其对于汇率波动率建模和预测具有重要作用。同时众多研究表明,时变风险厌恶(RA)包含了金融波动率预测的相关信息。鉴于此,本文构建带时变高阶矩的GARCH-MIDAS-SK模型框架,... 详细信息

经验研究表明汇率收益率分布呈现出时变高阶矩(偏度和峰度)特征,其对于汇率波动率建模和预测具有重要作用。同时众多研究表明,时变风险厌恶(RA)包含了金融波动率预测的相关信息。鉴于此,本文构建带时变高阶矩的GARCH-MIDAS-SK模型框架,进一步将RA指数引入该模型框架,实证检验RA对人民币汇率波动率的影响以及预测作用。实证结果表明:RA对人民币汇率波动率具有显著负的影响;人民币汇率收益率分布展现出明显的时变高阶矩特征;引入RA和时变高阶矩有助于提高模型的样本内拟合效果。基于损失函数和MCS检验证实了引入RA和时变高阶矩能够显著提高模型的样本外预测精度,且预测结果具有关于不同样本外预测阶段的稳健性。

关键词：时变风险厌恶时变高阶矩人民币汇率波动率 GARCH-MIDAS-SK模型 MCS检验

无充气后入路经锁骨下腔镜甲状腺手术治疗甲状腺乳头状癌的学习曲线及短期临床疗效

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中国普通外科杂志 2024年第5期33卷 848-855页

作者：陈浩浩刘岩岩马小鹏赵沨音正浪张洋安徽医科大学第三附属医院甲乳外科安徽合肥230061 中国科学技术大学附属第一医院甲乳外科安徽合肥230031 安徽理工大学第一附属医院普通外科安徽淮南232007

背景与目的:无充气后入路经锁骨下腔镜甲状腺手术由于切口隐蔽和术后吞咽障碍轻的优点,已被患者广泛接受。但中央区淋巴结后界的清扫仍存在不少的困难。笔者采用后入路的方式,可以很好地显露并清扫中央区淋巴结。本文通过累积和分析法(C... 详细信息

背景与目的:无充气后入路经锁骨下腔镜甲状腺手术由于切口隐蔽和术后吞咽障碍轻的优点,已被患者广泛接受。但中央区淋巴结后界的清扫仍存在不少的困难。笔者采用后入路的方式,可以很好地显露并清扫中央区淋巴结。本文通过累积和分析法(CUSUM)分析手术时间,探讨该术式应用于甲状腺乳头状癌治疗的学习曲线及短期临床疗效。方法:回顾性分析2022年1月—2023年8月连续在安徽医科大学第三附属医院甲乳外科接受无充气后入路经锁骨下腔镜甲状腺手术的100例甲状腺乳头状癌患者的临床资料。以CUSUM拟合学习曲线,并依此结果比较不同阶段各观察指标的差异。结果:所有患者均在腔镜下顺利完成,无中转开放。手术时间随着手术例数增加呈前期下降,后期趋于平稳的趋势。学习曲线最佳拟合为三次方曲线,拟合曲线在手术例数增加至33例时到达顶点,以此为界将学习曲线分为学习阶段和熟练阶段。学习阶段患者的手术时间明显长于熟练阶段[(151.85±39.46)min vs.(93.88±19.04)min,P0.05)。患者随访过程中无复发。结论:无充气后入路经锁骨下腔镜甲状腺手术治疗甲状腺乳头状癌安全可行,中央区显露良好,学习曲线短,适合推广开展。

关键词：甲状腺肿瘤甲状腺切除术内窥镜学习曲线

Comparative molecular docking studies of lupeol and lupenone isolated from Pueraria lobata that inhibits BACE1: Probable remedies for Alzheimer's disease

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Asian Pacific Journal of Tropical Medicine 2017年第12期10卷 1117-1122页

作者： Prashamsa Koirala Su Hui Seong Hyun ah Jung Jae Sue Choi Department of Food and Life Science Pukyong National University Department of Food Science and Human Nutrition Chonbuk National University

Objective: To discover lead lupane triterpenoid's potential isolated from Pueraria lobata roots against b-site amyloid precursor protein cleaving enzyme 1(BACE1), which serve as a rate limiting step in amyloid beta(Aβ) production altering the course of Alzheimer's disease. In addition, enzyme kinetics study and molecular docking were conducted to establish the inhibition type and structure activity ***: A systematic study of 70% ethanolic P. lobata root extract was employed to identify its BACE1 inhibitory potential. Further, BACE1 inhibitory potential of two lupane terpenoids, yielded from ethanolic extract, was assessed. In order to determine their inhibition mode, Lineweaver–Burk plots and Michaelis–Menten model for BACE1 was performed. Auto Dock 4.2 program in addition determined the molecular interaction of BACE1 with isolated ***: Considering the inhibitory potential of 70% ethanolic extract of P. lobata against BACE1(IC_(50)= 80.35 mg/mL), lupeol and lupenone were subsequently isolated and exhibited notable or moderate BACE1 inhibitory activity with IC_(50) values of 5.12 and 62.98 mmol/L, respectively, as compared to the positive control quercetin(IC_(50)= 21.28 mmol/L). The enzyme kinetics study enabled us to identify both compounds as competitive inhibitors, where lupeol displayed a very potent inhibition against BACE1 with low inhibition constant(Ki) value of 1.43 mmol/L, signifying greater binding *** order to understand the binding mechanism and structure–activity relationship of two triterpene-based BACE1 inhibitors, we employed computer aided docking studies which evidently revealed that hydroxyl group of lupeol formed two hydrogen bonds with the ASP32(catalytic aspartic residue) and SER35 residues of BACE1 with the binding energy of(-8.2 kcal/mol), while the ketone group of lupenone did not form any hydrogen bonds with BACE1 giving evidence for less binding affinity. These results in turn have predicted the dep

关键词： Pueraria lobata BACE1 Lupeol Lupenone Molecular docking Kinetics

An Efficient Character-Level Adversarial Attack Inspired by Textual Variations in Online Social Media Platforms

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Computer Systems Science & Engineering 2023年第12期47卷 2869-2894页

作者： Jebran Khan Kashif ahmad Kyung-ah Sohn Department of Artificial Intelligence Ajou UniversitySuwonKorea Department of Computer Science Munster Technological UniversityCorkIreland Department of Software and Computer Engineering Ajou UniversitySuwonKorea

In recent years,the growing popularity of social media platforms has led to several interesting natural language processing(NLP)***,these social media-based NLP applications are subject to different types of adversarial attacks due to the vulnerabilities of machine learning(ML)and NLP *** work presents a new low-level adversarial attack recipe inspired by textual variations in online social media *** variations are generated to convey the message using out-of-vocabulary words based on visual and phonetic similarities of characters and words in the shortest possible *** intuition of the proposed scheme is to generate adversarial examples influenced by human cognition in text generation on social media platforms while preserving human robustness in text understanding with the fewest possible *** intentional textual variations introduced by users in online communication motivate us to replicate such trends in attacking text to see the effects of such widely used textual variations on the deep learning *** this work,the four most commonly used textual variations are chosen to generate adversarial ***,this article introduced a word importance ranking-based beam search algorithm as a searching method for the best possible perturbation *** effectiveness of the proposed adversarial attacks has been demonstrated on four benchmark datasets in an extensive experimental setup.

关键词： Adversarial attack text classification social media character-level attack phonetic similarity visual similarity word importance rank beam search

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曹奕教授针药并用治疗耳鸣耳聋经验总结

广西中医药大学学报 2024年第5期27卷 46-49页

作者：王保国尹维帅曹奕(指导) 安徽中医药大学第二附属医院安徽合肥230061 安徽中医药大学安徽合肥230038 不详

该文总结曹奕教授治疗耳鸣耳聋的临床经验并附验案一则。曹奕教授认为耳鸣耳聋因外感邪气、阳气跃动、肺脾肾亏虚、肝胆疏泄失常等使耳部经气阻滞、耳窍失于濡养,导致耳之生理功能不能正常发挥而引起,其采用针刺与口服中药结合的方法治... 详细信息

该文总结曹奕教授治疗耳鸣耳聋的临床经验并附验案一则。曹奕教授认为耳鸣耳聋因外感邪气、阳气跃动、肺脾肾亏虚、肝胆疏泄失常等使耳部经气阻滞、耳窍失于濡养,导致耳之生理功能不能正常发挥而引起,其采用针刺与口服中药结合的方法治疗该病,针刺治疗讲究主配穴结合,兼顾头项,宁心调神;中药治疗注重调理脏腑气血,疏经通络开窍,在临床中取得较好的疗效。

关键词：耳鸣耳聋针灸疗法中药内服曹奕经验总结

Duodenum-preserving local excision of a gastrointestinal stromal tumor

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Hepatobiliary & Pancreatic Diseases International 2008年第2期7卷 214-216页

作者： Chandika ah Liyanage Sanjaya Abeygunawardhana Sumudu Kumarage Kemal I Deen Department of Surgery University of Kelaniya Medical School Ragama Sri Lanka

BACKGROUND:Duodenal gastrointestinal stromal tumors (GISTs) are rare. Because of the complex anatomy of the duodenum, the methods of resection of these tumors are controversial and diverse. METHODS:We report a case of a duodenal GIST in the anterolateral wall of the second part of the duodenum, which was successfully managed by local excision. The surgery was facilitated by preoperative mapping with Indian ink and navigation by endoscopy to assess the adequacy of resection and to avoid injury to the ampulla. RESULT:Reconstruction was successful with a duodeno-jejunostomy and protected by a nasoduodenal drain. CONCLUSION:The patient had no postoperative complications and the tumor was confirmed to be a GIST of the duodenum successful with an adequate resection margin.

关键词： gastrointestinal stromal tumor local excision, duodenum