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Overexpression of connexin 45 in rat mesenchymal stem cells improves the function as cardiac biological pacemakers

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Chinese Medical Journal 2010年第12期123卷 1571-1576页

作者： TONG Min YANG Xiang-jun geng bao-yu HAN Lian-huan ZHOU Ya-feng ZHAO Xin LI Hong-xia Department of Cardiology First Affiliated Hospital of SoochowUniversity Suzhou Jiangsu 215006 China

Background Extensive research toward creating a biological pacemaker by enhancement of inward depolarizing current has been performed. However, studies have mainly focused on inducing spontaneous activity and have not adequately addressed ways to improve pacemaker function. In this study we attempted to improve pacemaker function by altering connexin expression in rat mesenchymal stem cells （MSCs） to a phenotype similar to native sinus node pacemaker cells. Methods To generate a biological pacemaker, MSCs were transduced with a cardiac pacemaker gene- hyperpolarization-activated cyclic nucleotide-gated channel 4 （HCN4）, via transfection with a lentiviral vector. Funny current （If） in HCN4~ MSCs was recorded by voltage-clamp. Overexpression of connexin 45 （gene Gja7） in MSCs was achieved by transfection with the plasmid pDsRED2-N1-Gja7-RFP. Double-immunolabelling with anti-connexin 43 and anti-connexin 45 antibodies were used to identify the gap junction channels. The effects of the genetically modified MSCs on cardiomyocyte excitability were determined in MSCs cocultured with neonatal rat ventricular myocytes. Spontaneous action potentials of neonatal rat ventricular myocytes were recorded by current-clamp. Results High level time- and voltage-dependent inward hyperpolarization current that was sensitive to 4 mmol/L Cs＋ was detected in HCN4＋ MSCs, confirming that HCN4 acted as Ir channels in MSCs. Connexin 43 and connexin 45 were simultaneously detected in CX45＋ MSCs. Beating frequency was （82±8） beats per minute （n=-5） in myocytes cocultured with non-transfected control MSCs, versus （129±11） beats per minute （n=-5） in myocytes cocultured with HCN4＋ MSCs. Myocytes cocultured with MSCs cotransfected with HCN4 and connexin 45 had the highest beating frequency at （147±9） beats per minute （n=5）. Conclusion These findings demonstrate that overexpression of connexin 45 and subsequent formation of heteromeric connexin 45/connexin 43 gap junction channels in HCN4 expressing

关键词： pacemaker gap junction hyperpolarization-activated cyclic nucleotide-gated cation channel connexin45 gene therapy heart

Visible-light-responsive homologous heterostructure of oxynitrides constructed to boost charge separation and water splitting

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Science China Chemistry 2025年第01期 186-191页

作者： Hai Zou yunfeng bao Xueshang Xin yu Qi Tengfeng Xie Fuxiang Zhang State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences School of Chemistry and Chemical Engineering Liaoning Normal University College of Chemistry Jilin University

Constructing type II heterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated （oxy）nitrides with low thermal ***,we synthesized a homologous heterostructure （denoted as YTON＿H） based on the oxynitrides of YTaO4-xNyand YTa *** heterostructure exhibits type II band structure alignment and intimate interface achieved through a magnesium （Mg） powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained YTON＿H homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(YTaO4-xNyand YTaON2).Meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.

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唐山市高校学生信息素质教育现状分析与改进对策研究

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唐山职业技术学院学报 2016年第3期14卷 10-13页

作者：耿钰李宝群唐山职业技术学院河北唐山063004 唐山市科学技术信息情报研究所河北唐山063000

信息素质教育是当前教育改革的重要方面,信息素质作为大学生必备的素养之一,越来越受到重视。本文通过对唐山地区大学生信息素质的现状调查,并对获得的数据进行分析,指出了目前大学生信息素质存在的突出问题,同时,提出了相应的对策措施。

关键词：信息素质大学生调查分析

新工科背景下塑料模具设计实践课程教学改革研究

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教育教学论坛 2024年第52期 60-63页

作者：文成田玉琬余江耿保玉广东海洋大学机械工程学院广东湛江524088

新工科专业建设对模具行业人才培养提出了新的更高要求,通过对高校模具人才培养环节的核心课程——“塑料成型模具设计”现存问题的分析,从明确教学目标、优化教学内容、强化实践操作、校企协同育人等方面,指出课程实践教学模式的改革途... 详细信息

新工科专业建设对模具行业人才培养提出了新的更高要求,通过对高校模具人才培养环节的核心课程——“塑料成型模具设计”现存问题的分析,从明确教学目标、优化教学内容、强化实践操作、校企协同育人等方面,指出课程实践教学模式的改革途径,提出“虚实一体化”和“校企协同化”二维一体的教学理念和方法,改革中注重课程内容与实践及实际生产环节的互联互动、相互促进,以满足模具行业对创新型应用人才的知识和素养需求。

关键词：新工科塑料模具实践教学课程改革

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第01期 201-208页

作者： Hui-Feng Wang Wen-Jie Shi yu-Xin Yang bao-Xia Dong Tong-Bu Lu Di-Chang Zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

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不同改性方法对花生浓缩蛋白结构及功能特性的影响

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食品工业 2014年第10期35卷 186-190页

作者：曹迪范远景黄婷耿保玉陈伟杨效奎合肥工业大学生物与食品工程学院合肥230009 安徽凯利粮油食品有限公司合肥231600

利用中性蛋白酶改性花生浓缩蛋白,并与超声波物理改性方法比较,测定了改性前后花生浓缩蛋白的溶解性、吸水性、吸油性、乳化性及乳化稳定性、起泡性及泡沫稳定性。结果发现,两种改性方法均对花生浓缩蛋白的溶解性及吸油性有较大改善,分... 详细信息

利用中性蛋白酶改性花生浓缩蛋白,并与超声波物理改性方法比较,测定了改性前后花生浓缩蛋白的溶解性、吸水性、吸油性、乳化性及乳化稳定性、起泡性及泡沫稳定性。结果发现,两种改性方法均对花生浓缩蛋白的溶解性及吸油性有较大改善,分别比改性前的浓缩蛋白提高了61.44%和161.70%,47.34%和165.03%,但酶解改性蛋白的乳化稳定性及超声波改性蛋白的起泡稳定性则分别比改性前降低了11.60%和32.96%。经电镜、电泳及圆二色谱对蛋白质显微结构、分子量大小和二级结构的变化规律进行了研究,探讨了花生浓缩蛋白改性机理。

关键词：花生浓缩蛋白酶解改性超声波改性结构与功能性

De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期 174-180页

作者： Fan-Xiao Meng Xing-yu Wang Ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma bao Du Yong-Qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

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Investigating impacts of different building contents on the post-earthquake evacuation time using an agent-based model with considering turning behavior

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 939-955页

作者： bao yu School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park of Wuhan University of Technology Sanya 572025China

Accurate assessment of crowd evacuation inside the post-earthquake environment is critical from many perspectives,but this issue receives much less attention compared to the seismic losses of structural and non-structural *** could be attributed to the fact that post-earthquake evacuation analysis is complex due to the interaction between human behavior and the actual built environment induced by different building *** study attempts to tackle this problem by investigating the impacts of different building contents on post-earthquake evacuation time by using an agent-based model that considers turning *** this end,the agent-based model is first described,including:properties of the agent-based model with turning behavior,key aspects in its formulation considering different evacuation stages,and influence of different building contents(namely,debris from partition walls and ceiling systems,and various types of equipment)on the agent’s ***,a school building is used as a benchmark problem to validate the model without earthquake,and the findings indicate that the agent-based model can match the real safety drill results reasonably *** the validation,the school building is subsequently designed in accordance with modern seismic design codes,and the influence of debris and equipment on post-earthquake evacuation time is quantitatively studied using a suite of pulse-type ground motions as *** on this case study,recommendations are made for structural and architectural designers in an effort to reduce the potential evacuation ***,debris induced by partition walls or ceiling systems should be controlled as it has the greatest impact on the total evacuation time.

关键词： seismic fragility evacuation agent-based model route choice built environment

Improved formation density measurement using controllable D-D neutron source and its lithological correction for porosity prediction

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Nuclear Science and Techniques 2022年第1期33卷 24-34页

作者： Li Zhang Hua-Wei yu Yang Li Wen-bao Jia Xiao Han Xue-Sen geng College of Resources Shandong University of Science and TechnologyTai’an 271019China School of Geosciences China University of PetroleumQingdao 266580China College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an 271018China Department of Nuclear Science and Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Controllable D-D neutron sources have a long service life,low cost,and *** are favorable prospects for its application in geophysical well logging,since traditional chemical radioactive sources used for well logging pose potential threats to the safety of the human body and *** paper presents an improved method to measure formation density that employs a D-D neutron *** addition,the lithological effect on the measured density was removed to better estimate the formation ***,we investigated the spatial distribution of capture gamma rays through Monte Carlo simulations as well as the relationship between the ratio of capture gamma ray counts and formation density to establish theoretical support for the design of density logging tools and their corresponding data processing ***,we obtained the far to near detector counts of captured gamma rays for an optimized tool structure and then established its correlation with the density and porosity of three typical formations with pure quartz,calcite,and dolomite ***,we determined the values for correcting the densities of sandstone and dolomite with the same porosity using limestone data as the reference and established the equations for calculating the correction values,which lays a solid foundation for accurately calculating formation *** observed that the capture gamma ray counts first increased then decreased and varied in different formations;this was especially observed in high-porosity *** the same lithologic conditions(rock matrix),as the porosity increases,the peak value of gamma ray counts moves toward the neutron *** different detector-source distances,the ratio of the capture gamma ray counts was well correlated with the formation *** equation of the formation density conversion was established based on the ratio of capture gamma ray counts at the detector-source distances of 30 cm and 65 cm,and the calculate

关键词： Density measurement D-D neutron source Lithological correction Porosity prediction