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Cardiac regeneration: Pre-existing cardiomyocyte as the hub of novel signaling pathway

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Genes & Diseases 2024年第2期11卷 747-759页

作者： Tao Wang Xinzhe Chen Kai Wang Jie Ju Xue Yu Wanpeng Yu Cuiyun Liu Yin Wang Institute for Translational Medicine The Affiliated Hospital of Qingdao UniversityCollege of MedicineQingdao UniversityQingdaoShandong 266023China College of Medicine Qingdao UniversityQingdaoShandong 266023China

In the mammalian heart,cardiomyocytes are forced to withdraw from the cell cycle shortly after birth,limiting the ability of the heart to regenerate and *** development of multimodal regulation of cardiac proliferation has verified that pre-existing cardiomyocyte proliferation is an essential driver of cardiac *** the continuous development of genetic lineage tracking technology,it has been revealed that cell cycle activity produces polyploid cardiomyocytes during the embryonic,juvenile,and adult stages of cardiogenesis,but newly formed mononucleated diploid cardiomyocytes also elevated sporadically during myocardial *** implied that adult cardiomyocytes have a weak regenerative capacity under the condition of ischemia injury,which offers hope for the clinical treatment of myocardial ***,the regeneration frequency and source of cardiomyocytes are still low,and the mechanism of regulating cardiomyocyte proliferation remains further *** is noteworthy to explore what force triggers endogenous cardiomyocyte proliferation and heart ***,we focused on summarizing the recent research progress of emerging endogenous key modulators and crosstalk with other signaling pathways and furnished valuable insights into the internal mechanism of heart *** addition,myocardial transcription factors,non-coding RNAs,cyclins,and cell cycle-dependent kinases are involved in the multimodal regulation of pre-existing cardiomyocyte ***,awakening the myocardial proliferation endogenous modulator and regeneration pathways may be the final battlefield for the regenerative therapy of cardiovascular diseases.

关键词： Cardiac regeneration Cell cycle re-enter Myocardial infarction Pre-existing cardiomyocyte proliferation Regenerative therapy of cardiovascular diseases

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一种海洋环境噪声估计风速的修正法

声学学报 2006年第3期31卷 276-280页

作者：林建恒蒋国健苑泉乐衣雪娟中国科学院声学所(北站) 青岛266023

基于按风速分段法反演风速的研究,提出了一种海洋环境噪声估计风速的修正方法。该方法考虑了不同海域不同水声传播条件对风关环境噪声的影响,兼有判别雨、船等噪声源的功能。利用所提出修正法对中国近海某海域实测数据的处理表明,它可... 详细信息

基于按风速分段法反演风速的研究,提出了一种海洋环境噪声估计风速的修正方法。该方法考虑了不同海域不同水声传播条件对风关环境噪声的影响,兼有判别雨、船等噪声源的功能。利用所提出修正法对中国近海某海域实测数据的处理表明,它可适用于不同海域,具有较好的鲁棒性。在有应用意义的中风速段(15 m／s>v>6 m／s)和高风速段(v>15 m／s),该方法反演风速的误差不超过15％,小于WOTAN法反演风速的误差。修正法为海洋环境噪声实时反演风速系统应用于近海不同海域提供了良好的基础。

关键词：海洋环境噪声高风速噪声估计修正法中国近海系统应用修正方法水声传播实测数据反演

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部分充水有隔板弹性球壳的声散射

声学学报 2007年第4期32卷 369-374页

作者：孙阳徐海亭中国科学院声学研究所北海研究站青岛266023

根据弹性体运动方程和目标散射的积分方程,应用有限元和边界元方法(FEM/BEM)研究部分充水、结构弹性球壳的声散射特性,并计算了球壳内有、无隔板和部分充水情况的归一化散射形态函数,分析了谐振散射机理。结果表明,部分充水、无隔板球... 详细信息

根据弹性体运动方程和目标散射的积分方程,应用有限元和边界元方法(FEM/BEM)研究部分充水、结构弹性球壳的声散射特性,并计算了球壳内有、无隔板和部分充水情况的归一化散射形态函数,分析了谐振散射机理。结果表明,部分充水、无隔板球壳的谐振特性主要与充水情况有关,谐振是由内部水介质与球壳共同作用产生的;部分充水、有隔板球壳的主要谐振特性与无水情况的特性相差不大,内部水层中的声场较弱,说明谐振特性主要由球壳和隔板决定,但是,隔板一侧充满水时,球壳的散射特性与部分充水情况有很大不同。

关键词：声散射特性弹性球壳无隔板充水谐振特性边界元方法积分方程目标散射

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舰船螺旋桨空泡噪声的数理模型

声学学报 1998年第5期23卷 401-408页

作者：蒋国健林建恒马杰赵建平中国科学院声学所北海站青岛266023

探讨舰船螺旋桨空泡噪声指数衰减型随机脉冲序列的理论模型。据此理论模型，导得螺旋桨空泡噪声谱的表达式。结果表明，螺旋桨空泡噪声由连续谱和离散线谱组成。螺旋桨空泡噪声线谱的相对幅值取决于声脉冲前沿出现时刻的随机摆幅。高频... 详细信息

探讨舰船螺旋桨空泡噪声指数衰减型随机脉冲序列的理论模型。据此理论模型，导得螺旋桨空泡噪声谱的表达式。结果表明，螺旋桨空泡噪声由连续谱和离散线谱组成。螺旋桨空泡噪声线谱的相对幅值取决于声脉冲前沿出现时刻的随机摆幅。高频时线谱成分趋于零，低频段线谱成分甚大于相应的连续谱成分。高频段连续谱随频率的平方而下降，低频段连续谱随频率的平方而上升，在某一较低频率处出现谱峰。上述螺旋桨空泡噪声谱特性的理论结果和实际观测数据之间具有很好的一致性。

关键词：舰船噪声螺旋桨空泡噪声数理模型

加拿大中小学课堂评价改革管窥与启示——以WNCP《课堂评价再思考:有目的评价》为例

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课程．教材．教法 2013年第5期33卷 121-127页

作者：于立平青岛市教科所山东青岛266023

课堂评价是促进学生学习和发展的重要途径。但课堂评价"评什么"、"怎么评"、"为什么评"、"评了之后怎么做",还有待系统研究和实践探索。加拿大西北部各省教育协作联盟组织研制的《课堂评价再思考:有目的评价》,对加拿大课堂评价的价值... 详细信息

课堂评价是促进学生学习和发展的重要途径。但课堂评价"评什么"、"怎么评"、"为什么评"、"评了之后怎么做",还有待系统研究和实践探索。加拿大西北部各省教育协作联盟组织研制的《课堂评价再思考:有目的评价》,对加拿大课堂评价的价值目标、基本内容、实施策略进行了系统分析,对中国中小学课堂评价改革具有启示意义。

关键词：加拿大中小学课堂评价改革启示

Model of wind-generated ambient noise in stratified shallow water

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Chinese Journal of Oceanology and Limnology 2005年第2期23卷 144-151页

作者：林建恒高天赋 Qingdao Laboratory of Institute of Acoustics the Chinese Academy of Sciences Qingdao 266023 China Institute of Acoustics the Chinese Academy of Sciences Beijing 100080 China

In order to build a rapid ocean ambient noise model adapted for a stratified shallow water, a hybrid model of normal mode method (for far field) and ray method (for near field) is suggested which combines the advantages of both methods. Since the near field of wind-generated noise is not sensitive to the sound speed pro- file, the sound speed profile is regarded as a constant; which makes the model rapid and accurate. The simulation results are in agreement with those of the wave model.

关键词： wind-generated ambient noise ray normal mode hybrid model

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波导中目标的声散射

声学技术 2005年第Z1期24卷 15-16页

作者：高华徐海亭中科院北海研究站青岛266023 中科院北海研究站青岛266023

　　1引言　　在水平分层浅海波导内,目标的入射和散射特性都比在自由场中复杂,不仅边界面之间存在卢传播的多次反射,而且目标和界面之间也存在多次反射,所以浅海中目标散射场必然具有较强的相干起伏特征.从八十年代末期各国开始重视研... 详细信息

　　1引言　　在水平分层浅海波导内,目标的入射和散射特性都比在自由场中复杂,不仅边界面之间存在卢传播的多次反射,而且目标和界面之间也存在多次反射,所以浅海中目标散射场必然具有较强的相干起伏特征.从八十年代末期各国开始重视研究这个问题,如Ingenito1采用的本征函数展开法研究了在水平分层介质上均匀流体中刚性球的散射;Athanassoulis2等人研究了浅海中柱岛的散射.而大多数目标在波导中的散射问题没有准确解,通常采用数值方法求解.赵洪3采用边界积分及单一矩方法研究过浅海短柱的散射.　　……

关键词：浅海波导目标散射问题水平分层多次反射本征函数展开法重视研究数值方法散射特性起伏特征均匀流体边界面分层介质方法研究边界积分自由场准确解散射场刚性球相干

An approach to the detection of underwater remote target

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Chinese Journal of Acoustics 2004年第1期23卷 88-96页

作者： CHENXixin JIANGGuojian XUXinsheng XUXinsheng1 QingdaoAcousticsLaboratory InstituteofAcousticsAcademiaSinicaQingdao266023 HarbinEngineeringUniversityHarbin150001

An approach to the detection of underwater remote target by estimating its back-scattering coefficient is presented. The key to this approach is that the echo signal is represented in state-variable model and the back-scattering coefficients of target are contained in dynamic noise of this model, thus underwater target can be detected by estimating this dynamic noise, i.e., deconvolving this model. When all noise statistics are a priori known, an optimum deconvo-lution algorithm based on the optimum state filter is derived, or else, an adaptive deconvolution algorithm based on the adaptive state filter of alternatively estimating the vector state and the noise statistics is developed. In the final simulation test, an echo signal with SNR equal to -6.1 dB is proceeded using the aforementioned two deconvolution algorithms, respectively, and the results demonstrate good performance of the approach.

关键词： An approach to the detection of underwater remote target

Sound scattering from partially water-filled elastic spherical shell with an internal elastic plate

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Chinese Journal of Acoustics 2008年第2期27卷 111-118页

作者： SUN Yang XU Haiting Qingdao Acoustics Laboratory Institute of Acoustics Chinese Academy of Sciences Qingdao 266023

According to the equation of motion in the elastic medium and integral equation of target scattering, the sound scattering from the partially water-filled elastic spherical shells with and without an inner plate is studied using the finite element and boundary element method, and the scattering normalized form functions of the shell filled with different volume of water are computed and the mechanism of resonance scattering is analyzed. The results show that the resonance of the shell with partially water-filled and without the plate is mainly related to the volume of water, and the resonance is produced by inner water and the spherical shell. The resonance characteristics of partially water-filled elastic shell with the plate are similar to that of empty structured elastic spherical shell, and the sound field in inner water is weaker which indicates the main resonance characteristics are decided by spherical shell and the plate. In addition, the scattering characteristics of spherical shell with plate and one side full water-filled are greatly different from the partially water-filled ones.

关键词： Sound scattering from partially water-filled elastic spherical shell with an internal elastic plate mode