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Semilinear Elliptic Resonant Problems at Higher Eigenvalue with Unbounded Nonlinear Terms

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Acta Mathematica Sinica,English Series 1998年第3期14卷 411-418页

作者： su jiabao Institute of Mathematics, Academia Sinica, Beijing 100080, China Department of Mathematics. Capital Normal University, Beijing 100037, China Institute of Mathematics Academia Sinica Beijing China Department of Mathematics Capital Normal University Beijing China

In this paper we study the existence of nontrivial solutions of a class of asymptotically linear elliptic resonant problems at higher eigenvalues with the nonlinear term which may be un- bounded by making use of the M... 详细信息

关键词： Math Semilinear Elliptic Resonant Problems at Higher Eigenvalue with Unbounded Nonlinear Terms

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具有凸凹项非齐次拟线性椭圆方程的多解性

数学物理学报（A辑） 2014年第2期34卷 217-226页

作者：梁占平苏加宝山西大学数学科学学院太原030006 首都师范大学数学科学学院北京100037

在Orlicz—Sobolev空间中利用临界点理论考虑了非齐次拟线性椭圆方程{-div((︱▽u︱)▽u)=μ︱u︱q-2u+λ︱u︱p-2u在Ω中,u=0在Ω上无穷多解的存在性,其中Ω是R^N中边界光滑的有界区域,μ,λ∈R是两个参数.

关键词：非齐次拟线性椭圆方程 Orlicz-Sobolev空间临界点理论

数字压力量表在中国大学生中的修订及信效度验证

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北京大学学报（自然科学版） 2023年第6期59卷 1025-1034,I0001,I0002页

作者：刘秋琪苏嘉宝魏世娟喻晓妍周广玉行为与心理健康北京市重点实验室北京大学心理与认知科学学院北京100871

对Hall等的数字压力量表(Digital Stress Scale,DSS)进行本土化修订,并检验修订版在国内大学生中的信效度。在样本1(样本量n=15)中访谈数字压力,在4个方便抽样大学生样本中(样本2,3,4和5的n分别为87,100,300和239)对数字压力量表进行项... 详细信息

对Hall等的数字压力量表(Digital Stress Scale,DSS)进行本土化修订,并检验修订版在国内大学生中的信效度。在样本1(样本量n=15)中访谈数字压力,在4个方便抽样大学生样本中(样本2,3,4和5的n分别为87,100,300和239)对数字压力量表进行项目分析、验证性因素分析、结构效度、效标关联效度及信度分析。选取抑郁–焦虑–压力自评量表、生活满意度、UCLA孤独感量表、领悟社会支持和Bergen社交媒体成瘾量表为效标。两周后,对样本5中156名大学生进行重测。修订中文版DSS(Revised Chinese Digital Stress Scale,RC-DSS)中31个条目,包括可联系性压力、认可焦虑、社会比较、错失焦虑、信息过载和在线警戒性6个因子。项目鉴别度和题总分析显示条目表现良好,验证性因素分析显示六因子模型拟合程度良好(χ2/df=2.82,GFI=0.80,NFI=0.93,TLI=0.95,CFI=0.96,RMSEA=0.08)。数字压力与社交媒体成瘾、压力、抑郁、焦虑和孤独感显著正相关(r为0.41~0.61,p都小于0.01),与社会支持和生活满意度显著负相关(r=-0.24,p<0.01;r=-0.15,p<0.05)。量表内部一致性信度为0.94,重测信度为0.73(p<0.01)。RC-DSS具良好的信效度,适用于测量国内大学生的数字压力。

关键词：数字压力社交媒体心理健康

USP22在糖尿病小鼠心肌缺血再灌注损伤中的作用

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中华麻醉学杂志 2024年第10期44卷 1247-1252页

作者：苏家宝陈果郑观利邱弘博蔡维维侯豹朱雪雪张继如江南大学附属医院麻醉科无锡214122 江南大学无锡医学院无锡214122

目的评价泛素特异性蛋白酶22(USP22)在糖尿病小鼠心肌缺血再灌注损伤中的作用。方法SPF级雄性C57BL/6小鼠78只,6~8周龄,采用随机数字表法分为6组:假手术组(Sham组,n=12)、1型糖尿病+假手术组(T1D+Sham组,n=12)、心肌缺血再灌注损伤组(I/... 详细信息

目的评价泛素特异性蛋白酶22(USP22)在糖尿病小鼠心肌缺血再灌注损伤中的作用。方法SPF级雄性C57BL/6小鼠78只,6~8周龄,采用随机数字表法分为6组:假手术组(Sham组,n=12)、1型糖尿病+假手术组(T1D+Sham组,n=12)、心肌缺血再灌注损伤组(I/R组,n=12)、1型糖尿病+心肌缺血再灌注损伤组(DI/R组,n=12)、1型糖尿病+心肌缺血再灌注损伤+空载体质粒组(DI/R+V组,n=15)和1型糖尿病+心肌缺血再灌注损伤+USP22过表达组(DI/R+U组,n=15)。采用腹腔注射链脲佐菌素-柠檬酸盐缓冲液的方法制备1型糖尿病模型。采用结扎左冠状动脉的方法制备心肌缺血再灌注损伤模型。DI/R+U组和DI/R+V组于心肌缺血再灌注损伤造模前1 d分别于心脏原位注射USP22过表达质粒或者空载体质粒。心肌缺血再灌注24 h时,采用心脏超声检测心功能(左室射血分数和左室短轴缩短率)。随后处死小鼠,取心脏,测定心肌梗死面积,观察心肌组织病理学变化(HE染色),检测细胞凋亡率(TUNEL染色)和ROS活性(DHE染色),采用Western blot法、免疫荧光和免疫组化法检测USP22的表达。蛋白质组学分析USP22调控的下游蛋白质,通过免疫沉淀实验检测蛋白质相互作用。结果与Sham组相比,I/R组心功能指标下降,心肌细胞凋亡率和ROS活性升高,心肌组织USP22表达下调(P<0.05);与I/R组相比,DI/R组心肌梗死面积百分比增加,心功能指标下降,心肌细胞凋亡率和ROS活性升高,USP22表达上调(P<0.05),心肌组织病理学损伤加重;与DI/R+V组相比,DI/R+U组心肌梗死面积百分比减少,心功能指标升高,心肌细胞凋亡率和ROS活性降低,心肌组织USP22表达上调(P<0.05),心肌组织病理学损伤减轻。蛋白质组学结合免疫沉淀实验结果显示钙调蛋白1(CNN1)与USP22有相互作用。结论糖尿病小鼠心肌缺血再灌注损伤时,USP22可能为其内源性保护机制;CNN1可能是USP22发挥保护作用的下游机制。

关键词：心肌再灌注损伤糖尿病泛素特异性蛋白酶类

Ultrasensitive Label-free Detection of miRNA with Asymmetric Hairpin Probe, Exonuclease I and SYBR Green I

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Chemical Research in Chinese Universities 2015年第2期31卷 244-248页

作者： LIU Yingxin su Hongyan LONG jiabao CAO Qingfeng YAN Shuya MENG Xiangxian CAI Qingyun College of Biology State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha 410082 P. R. China Department of Bioengineering and Environment Science Changsha University Changsha 410003 P. R. China

Detection of miRNAs presents a particular challenge because of their limited size, high sequence homo- logy and greatly various expression level. In this work, an ultrasensitive, label-free and isothermal miRNA detection was developed based on asymmertric hairpin probe, exonuclease I（Exo I） and SYBR Green I. The method employed asymmetric hairpin probe to perform cycled polymerization and Exo I to reduce background signal. In the presence of the target miRNA, the target triggers probe-mediated cycled polymerization reactions to generate lots of dsDNA products. The dsDNA product effectively prevents itself from being degraded by Exo I and permitted the insertion of more fluorescence dye into it to enlarge the fluorescence signal. In the absence of the target miRNA, there was no probe-mediated polymerization reaction, and the probe was digested by Exo I added, which minimized the intercala- tion of fluorescence dye to reduce the background signal. The combination of the probe-mediated cycled polymeriza- tion with the Exo 1-assisted background reduction allows us to achieve a detection limit of 5× 10^-18 mol/L. Owing to its ultrasensitivity, excellent specificity, convenience and low-cost, this method might hold out great promise in miRNA detection.

关键词： Ultrasensitive miRNA Asymmetric hairpin probe Exonuclease I

Multiomics analysis provides new insights into the regulatory mechanism of carotenoid biosynthesis in yellow peach peel

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Molecular Horticulture 2023年第1期3卷 81-97页

作者： Jiarui Zheng Xiaoyan Yang jiabao Ye Dongxue su Lina Wang Yongling Liao Weiwei Zhang Qijian Wang Qiangwen Chen Feng Xu College of Horticulture and Gardening Yangtze UniversityJingzhou 434025China School of Biology and Agriculture Shaoguan UniversityShaoguan 512005China Guangdong Provincial Key Laboratory of Utilization and Conservation of Food and Medicinal Resources in Northern Region Shaoguan UniversityShaoguan 512005China

Carotenoids,as natural tetraterpenes,play a pivotal role in the yellow coloration of peaches and contribute to human dietary *** a relatively clear understanding of the carotenoid biosynthesis pathway,the regulatory mechanism of miRNAs involved in carotenoid synthesis in yellow peaches remain poorly *** study investigated a total of 14 carotenoids and 40 xanthophyll lipids,including six differentially accumulated carotenoids:violaxanthin,neoxanthin,lutein,zeaxanthin,cryptoxanthin,and(E/Z)-*** integrated analysis of RNA-seq,miRNA-seq and degradome sequencing revealed that miRNAs could modulate structural genes such as PSY2,CRTISO,ZDS1,CHYB,VDE,ZEP,NCED1,NCED3 and the transcription factors NAC,ARF,WRKY,MYB,and bZIP,thereby participating in carotenoid biosynthesis and *** authenticity of miRNAs and target gene was corroborated through quantitative real-time ***,through weighted gene coexpression network analysis and a phylogenetic evolutionary study,coexpressed genes and MYB transcription factors potentially implicated in carotenoid synthesis were *** results of transient expression experiments indicated that mdm-miR858 inhibited the expression of PpMYB9 through targeted *** upon these findings,a regulatory network governing miRNA-mediated carotenoid synthesis was *** summary,this study comprehensively identified miRNAs engaged in carotenoid biosynthesis and their putative target genes,thus enhancing the understanding of carotenoid accumulation and regulatory mechanism in yellow peach peel and expanding the gene regulatory network of carotenoid synthesis.

关键词： Yellow peach peel Carotenoid miRNA MYB Degradome

An Interfacial Gel Electrode Patch with Tunable Hydrogen Bond Network for Electromyographic Sensing and Discrimination

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CCS Chemistry 2024年第2期6卷 450-464页

作者： Jianliang Li Zhihao Liu Yongtao Tang jiabao Xian Chaofan He Hao Wu Mingjie Liu Fengyu Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsSu Bingtian Center for Speed Research and TrainingJinan UniversityGuangzhou 510632 School of Chemistry Beihang UniversityBeijing 100191

The sensitivity and fidelity of surface electromyography(sEMG)signal monitoring is critical for muscle status and fatigue assessment,prosthetic control,and gesture ***,the incompatible skin-electrode interface and complex electrophysiological environment restrict the sensitive acquisition and accurate analysis of sEMG *** on the impedance of the skin-electrode interface issue,we developed an interfacial gel electrode patch with a tunable hydrogen bond network to simultaneously achieve a conformal interface,suitable adhesion,and high conductivity for sEMG signal *** exploiting hydroxyethylidene diphosphonic acid(HEDP)and 2-hydroxyphosphono-acetic acid(HPAA)as hydrogen bonding regulators were introduced into the polyvinyl alcohol(PVA)-based hydrogel network to regulate the hydrogen bond cross-linking *** a result,the balance of elastic modulus,adhesion,and electrical conductivity of PVA-HEDP-HPAA(PHH)hydrogel are *** reliable electrodeskin interface is manipulated to achieve conformal contact by matching the elastic modulus,reducing the gap of electrode-skin interface by adhesion,and promoting ion and electron conduction by electrical *** PHH electrode patches exhibit a lower interfacial impedance(12.56 kΩ)and a signal-to-noise ratio of 38.09±1.28 dB for accurate analysis of muscle strength and evaluation of the fatigue *** the assistance of the artificial neural network algorithm,seven gestures can be recognized with 100%prediction *** interfacial gel electrode patch contributes a bio-matching electrophysiological platform for prosthetic control,human–machine interaction,and clinical or athletic auxiliary monitoring.

关键词： hydrogel electrode hydrogen bond network surface electromyography muscle fatigue artificial neural network gesture recognition

声发射技术在热障涂层失效机理中的研究进展及展望

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中国表面工程 2023年第2期36卷 34-53页

作者：曹枝军袁建辉苏怀宇万家宝苏佳卉吴倩王亮上海工程技术大学材料工程学院上海201620 中国科学院上海硅酸盐研究所集成计算材料研究中心上海201899

热障涂层(TBCs)具有优异的高温抗氧化、高温力学和抗热腐蚀性能而备受关注,广泛应用于航空发动机和燃气轮机热端部件中。热障涂层服役环境的恶劣和涂层体系结构的复杂,极易导致涂层发生界面分层或剥落失效,因此通过对热障涂层的裂纹萌... 详细信息

热障涂层(TBCs)具有优异的高温抗氧化、高温力学和抗热腐蚀性能而备受关注,广泛应用于航空发动机和燃气轮机热端部件中。热障涂层服役环境的恶劣和涂层体系结构的复杂,极易导致涂层发生界面分层或剥落失效,因此通过对热障涂层的裂纹萌生和扩展问题进行实时监测,对于失效机理研究显得尤为重要。简述光激发荧光压电光谱(PLPS)、红外热成像(IRT)、阻抗谱(IS)的原理及其在热障涂层失效行为研究中的应用,重点介绍声发射技术在热障涂层失效机理方面的研究成果。基于声发射的热障涂层失效过程的信号分析和深度处理,结合声发射技术在热障涂层中的参数分析和波形分析,对热障涂层失效过程及失效形态进行模式识别,通过损伤程度的定量评估来进行热障涂层的寿命预测。对声发射技术在热障涂层失效预测及寿命评估指明了方向,并创新性地对未来声发射技术在热障涂层的疲劳损伤方面研究趋势提出展望。

关键词：热障涂层声发射失效机理模式识别机器学习

基于原位声发射信号的热障涂层三点弯曲失效模式的机器学习

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硅酸盐学报 2023年第2期51卷 373-388页

作者：曹枝军袁建辉苏怀宇万家宝苏佳卉吴倩王亮上海工程技术大学材料科学与工程学院上海201620 中国科学院上海硅酸盐研究所集成计算材料研究中心上海201899

由于热障涂层体系结构的复杂和服役环境的恶劣,极易导致涂层发生界面分层、宏观断裂和剥落失效。首先利用声发射技术实时监测了热障涂层在三点弯曲载荷下的失效过程,结合微观形貌特征、声发射参数分析、K-means聚类分析识别了热障涂层... 详细信息

由于热障涂层体系结构的复杂和服役环境的恶劣,极易导致涂层发生界面分层、宏观断裂和剥落失效。首先利用声发射技术实时监测了热障涂层在三点弯曲载荷下的失效过程,结合微观形貌特征、声发射参数分析、K-means聚类分析识别了热障涂层损伤失效模式。然后利用Fourier变换、小波包变换等分析了4种失效模式的波形特征,其中宏观断裂或剥落失效信号无明显频带,而基底变形、表面垂直裂纹、剪切型界面裂纹、张开型界面裂纹对应的频率分布范围分别在62.5~125.0 kHz、187.5~250.0 kHz、250.0~312.5 kHz、375.0~437.5 kHz。采用机器学习的方法对原位声发射信号进行了深度处理,提取小波能量系数作为机器学习反向传播神经网络的特征向量,结合收敛曲线、混淆矩阵、受试者工作特征曲线、F1值评价了该模型优劣性,实现了对于热障涂层失效模式的判别,为热障涂层失效预测和寿命评估提供参考价值。

关键词：热障涂层三点弯曲声发射失效模式反向传播神经网络