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CRISPR/Cas9-mediated gene editing in human tripronuclear zygotes

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Protein & Cell 2015年第5期6卷 363-372页

作者： Puping Liang Yanwen Xu Xiya zhang chenhui Ding Rui Huang Zhen zhang Jie Lv Xiaowei Xie Yuxi Chen Yujing Li Ying Sun Yaofu Bai Zhou Songyang Wenbin Ma Canquan Zhou Junjiu Huang Guangdong Province Key Laboratory of Reproductive Medicine the First Affiliated Hospital and Key Laboratory of GeneEngineering of the Ministry of Education School of Life Sciences Sun Yat-sen University Guangzhou 510275 China

Genome editing tools such as the clustered regularly interspaced short palindromic repeat （CRISPR）-associated system （Cas） have been widely used to modify genes in model systems including animal zygotes and human cells, and hold tremendous promise for both basic research and clinical applications. To date, a serious knowledge gap remains in our understanding of DNA repair mechanisms in human early embryos, and in the efficiency and potential off-target effects of using technologies such as CRISPR/Cas9 in human pre-implantation embryos. In this report, we used tripronuclear （3PN） zygotes to further investigate CRISPR/Cas9-mediated gene editing in human cells. We found that CRISPR/Cas9 could effectively cleave the endogenous β-globin gene （HBB）. However, the efficiency of homologous recombination directed repair （HDR） of HBB was low and the edited embryos were mosaic. Off-target cleavage was also apparent in these 3PN zygotes as revealed by the T7E1 assay and whole-exome sequencing. Furthermore, the endogenous delta-globin gene （HBD）, which is homologous to HBB, competed with exogenous donor oligos to act as the repair template, leading to untoward mutations. Our data also indicated that repair of the HBB locus in these embryos occurred preferentially through the non-crossover HDR pathway. Taken together, our work highlights the pressing need to further improve the fidelity and specificity of the CRISPR/Cas9 platform, a prerequisite for any clinical applications of CRSIPR/Cas9-mediated editing.

关键词： CRISPR/Cas9 β-thalassemia humantripronuclear zygotes gene editing homologousrecombination whole-exome sequencing

Delineation of urban growth boundary based on FLUS model under the perspective of land use evaluation in hilly mountainous areas

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Journal of Mountain Science 2024年第5期21卷 1647-1662页

作者： zhang Yunping LIN Jianping HUANG Yimin CHEN Zebin ZHU chenhui YUAN Hao School of Geography and Environmental Engineering Gannan Normal UniversityGanzhou 341000China Key Laboratory of Low Carbon Recycling Technology for Municipal Solid Waste in Jiangxi Province Ganzhou 341000China

With rapid economic development,the size of urban land in China is expanding *** Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control the urban *** delineation of UGB can inhibit the disorderly spread of urban space and guide the normal development of the *** is of practical significance for the construction of green urban *** study utilizes GIS technology to establish a land construction suitability evaluation system for Nankang city,which is experiencing rapid urban expansion,and outlines the preliminary UGB under the future land use simulation(FLUS)*** the same time,considering the coupled coordination of"Production-Living-Ecological Space",and based on the suitability evaluation,we revised the preliminary UGB by combining the advantages of the patch-generating land use simulation(PLUS)model and the convex hull model to delineate the final *** results show that:1)the comprehensive score of the evaluation of the suitability of the construction of land from high to low shows the distribution of the center of the city to the surrounding circle type spread,the center of the city has the highest suitability *** results of convex hull model show that the urban expansion type of Nankang is *** the future,the urban expansion will mainly occur in the northern part of the *** PLUS model predicts an increase of 3359.97 hm^(2)of construction land in Nankang by 2035,of which 2022.97 hm^(2)is urban construction land.2)The FLUS model has a prediction accuracy of 86.3%and delineates a preliminary UGB area of 9215.07 hm^(2).3)We used the results of the construction suitability evaluation,PLUS model simulation results,and convex hull model predictions to revise the originally delineated *** final delineated UGB area is 8895.67 hm^(2)and it is capable of meeting the future development of the study *** results of the delineation can promote

关键词： Urban sprawl FLUS model Spatial correction Urban growth boundary Sustainable development

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钢帘线拉拔液润滑特性研究

摩擦学学报 2021年第2期41卷 260-267页

作者：王岩张晨辉清华大学摩擦学国家重点实验室北京100084

本文中针对钢帘线拉拔过程中出现的断丝原因进行了分析.同时,对两种拉拔液的润滑性能进行了研究.分别使用三维白光表面形貌仪、扫描电子显微镜、X射线光电子能谱对摩擦副的表面形貌、表面微观结构和表面成分进行了分析,并讨论了两种拉... 详细信息

本文中针对钢帘线拉拔过程中出现的断丝原因进行了分析.同时,对两种拉拔液的润滑性能进行了研究.分别使用三维白光表面形貌仪、扫描电子显微镜、X射线光电子能谱对摩擦副的表面形貌、表面微观结构和表面成分进行了分析,并讨论了两种拉拔液的润滑机理,以及对断丝和与橡胶粘附性的影响.

关键词：钢帘线拉拔液润滑磨损乳化液

High performance and stable pure-blue quasi-2D perovskite light-emitting diodes by multifunctional zwitterionic passivation engineering

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Advanced Photonics 2024年第2期6卷 32-40页

作者： Chao Shen Shuyan Fang Jibin zhang Xiangfei Liang chenhui Su Jian Qing Wanzhu Cai Yunhan Luo Renqiang Yang Lintao Hou Jinan University College of Physics and Optical Engineering Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy Materials Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials Jinan University College of Physics and Optical Engineering Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Zhengzhou University School of Physics and Microelectronics Key Laboratory of Materials Physics of Ministry of Education Jinan University Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Education Institutes Jianghan University School of Optoelectronic Materials and Technology Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education

Despite the rapid advances of red and green perovskite light-emitting diodes（Pe LEDs）, achieving high brightness with high external quantum efficiency（EQE） remains a challenge for the pure-blue Pe LEDs,which greatly hinders their practical applications, such as white-light illumination and in optical communication as a high-speed and low-loss light source. Herein, we report a high-performance pure-blue Pe LED based on mixed-halide quasi-2D perovskites incorporated with a zwitterionic molecule of 3-（benzyldimethylammonio）propanesulfonate（3-BAS）. Experimental and density functional theory analysis reveals that 3-BAS can simultaneously eliminate non-radiative recombination loss, suppress halide migration, and regulate phase distribution for smoothing energy transfer in the mixed-halide quasi-2D perovskites, leading to the final perovskites with high photoluminescence quantum yield and robust spectrum stability. Thus, the highperformance pure-blue Pe LED with a recorded brightness with 1806 cd m;-2;and a relative higher EQE of 9.25% is achieved, which is successfully demonstrated in a visible light communication system for voice signal transmission. We pave the way for achieving highly efficient pure-blue Pe LEDs with great application potential in future optical communication networks.

关键词： pure-blue PeLEDs quasi-2D perovskite zwitterionic additive visible light communication

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基于塑性材料模型的滚动轴承有限元分析

机械工程学报 2010年第11期46卷 29-35页

作者：徐弘毅张晨辉清华大学摩擦学国家重点实验室北京100084

重载滚动轴承是一种广泛应用于大型机械操作设备中的零件,其内部的高应力状态对轴承的寿命有着重大的影响。在ANSYSLS-DYNA环境下通过建立滚子轴承的多体动力接触有限元模型,通过选用双线性等向强化模型和双线性随动强化模型这两种不同... 详细信息

重载滚动轴承是一种广泛应用于大型机械操作设备中的零件,其内部的高应力状态对轴承的寿命有着重大的影响。在ANSYSLS-DYNA环境下通过建立滚子轴承的多体动力接触有限元模型,通过选用双线性等向强化模型和双线性随动强化模型这两种不同的材料塑性变形模型,计算不同变形本构关系材料模型的低速轴承在两种工况下中的应力状况。之后将计算结果与前人工作中采用的线弹性材料模型的方法所得出的结果相比较,研究塑性变形对轴承内部应力计算产生的影响,对改进重载轴承的设计具有指导作用。仿真结果表明,采用塑性材料模型建模计算出的应力值较弹性材料模型的计算结果小,选用不同材料模型对运转的卡死时间也有较大的影响,从而在计算出的轴颈下沉量中,弹性材料模型的结果要远小于塑性材料模型的结果。

关键词：滚动轴承显示动力学有限元塑性变形

焊接H形截面钢柱板组弹塑性相关屈曲和容许宽厚比

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东南大学学报（自然科学版） 2016年第3期46卷 523-531页

作者：邓长根张晨辉周江同济大学土木工程学院上海200092

建立了竖向轴压力和单调水平荷载作用下焊接H形截面悬臂钢柱板组弹塑性相关屈曲的有限元分析模型,通过改变轴压比、翼缘宽厚比、腹板高厚比及翼缘-腹板厚度比等参数,对非特厚实截面钢柱进行几何非线性和材料非线性有限元分析.然后,基于... 详细信息

建立了竖向轴压力和单调水平荷载作用下焊接H形截面悬臂钢柱板组弹塑性相关屈曲的有限元分析模型,通过改变轴压比、翼缘宽厚比、腹板高厚比及翼缘-腹板厚度比等参数,对非特厚实截面钢柱进行几何非线性和材料非线性有限元分析.然后,基于分析结果,利用最小相对误差拟合法得到极限弯矩比的实用计算公式.最后,基于整体-局部等稳原则导出板组容许宽厚比相关曲线方程,并通过算例对容许宽厚比相关曲线与钢结构设计规范的翼缘和腹板宽厚比限值曲线进行比较.结果表明:构件长细比较小时,规范规定的翼缘和腹板宽厚比限值可能超出容许宽厚比相关曲线限定的范围;翼缘宽厚比与腹板高厚比限值相关,并且两者均随轴压比、翼缘-腹板厚度比、构件长细比、塑性发展系数的变化而变化.

关键词：焊接H形截面局部相关屈曲弹塑性极限弯矩比宽厚比限值

Revealing the vertical structure of in-situ fabricated perovskite nanocrystals films toward efficient pure red light-emitting diodes

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Fundamental Research 2024年第2期4卷 362-368页

作者： Xian-gang Wu Shipei Sun Tinglu Song Xin zhang chenhui Wang Yingguo Yang Shuangpeng Wang Haizheng Zhong MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China Experimental Center of Advanced Materials School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China Shanghai Synchrotron Radiation Facility(SSRF) Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201204China Institute of Applied Physics and Materials Engineering University of MacaoMacao 999078China

The development of efficient perovskite light-emitting diodes(PeLEDs)relies strongly on the fabrication of perovskite films with rationally designed structures(grain size,composition,surface,etc.).Therefore,an understanding of structure-performance relationships is of vital importance for developing high-performance perovskite devices,particularly for devices with in-situ fabricated perovskite nanocrystal *** this study,we reveal the vertical structure of an in-situ fabricated quasi-two-dimensional perovskite *** combining time-of-flight secondary ion mass spectrometry,energy dispersive spectroscopy,grazing incidence wide-angle X-ray scattering(GIWAXS),and low-temperature photoluminescence spectra,we illustrate that the resulting in-situ fabricated DPPA_(2)Cs_(n-1)Pb_(n)(Br_(0.3)I_(0.7))_(3n+1)(DPPA^(+):3,3-diphenylpropylammonium)film has a gradient structure with a very thin layer of ligands on the surface,predominantly small-n domains at the top,and predominantly large-n domains at the bottom owing to the solubility difference of the *** addition,GIWAXS measurements show that the domain of n=2 on the top layer has an ordered in-plane *** on the understanding of the film structure,we developed an in-situ fabrication process with ligand exchange to achieve efficient pure red PeLEDs at 638 nm with an average external quantum efficiency(EQE)of 7.4%.The optimized device had a maximum luminance of 623 cd/m^(2) with a peak EQE of 9.7%.

关键词： Light-emitting diodes Perovskite TOF-SIMS Vertical structure in-situ fabrication

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政治参与的谱系学研究：民族教育提案的观察

教育学术月刊 2016年第4期 35-41页

作者：张宸珲北京大学教育学院/中国教育财政科学研究所北京100871

在政治参与理论背景下,通过对全国政协教育类别提案的整理,对其中涉及民族教育的提案进行了归纳整理和描述分析,运用政治谱系学的研究方法,对中国特色的"提案式政治参与"问题进行了总结。围绕"提案数量"、"提案类别"、"地域分布"、"财... 详细信息

在政治参与理论背景下,通过对全国政协教育类别提案的整理,对其中涉及民族教育的提案进行了归纳整理和描述分析,运用政治谱系学的研究方法,对中国特色的"提案式政治参与"问题进行了总结。围绕"提案数量"、"提案类别"、"地域分布"、"财政问题"等四个维度,对提案进行了"全国性问题"和"局部性问题"的对比研究;围绕"民族身份"、"工作身份"、"单位层级"等三个维度,对提案人进行了对比研究。发现民族教育提案与全国政协提案总体变化规律存在明显的不同,以是否涉及全国性问题为分界点,民族自治区与非民族自治区、中央委员与地方委员,形成了显著差异。

关键词：政治参与政协提案民族教育

基于数字孪生的空气预热器预测性维护模式研究

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发电技术 2024年第4期45卷 622-632页

作者：刘旺陈连龚高阳李智华薛文华石金刚谢军李雷雷姚荣财王召鹏杨延西邓毅张晨辉国能寿光发电有限责任公司山东省寿光市262714 东方电气集团东方锅炉股份有限公司四川省成都市611731 西安理工大学自动化与信息工程学院陕西省西安市710048

【目的】为解决大型火电机组空气预热器传统预防性维护手段的弊端,提出了一种基于数字孪生预测性维护的一般模式,并基于数字孪生技术,构建空气预热器数字孪生系统。【方法】所提系统包括回转式空气预热器物理实体、实时数据采集与分析... 详细信息

【目的】为解决大型火电机组空气预热器传统预防性维护手段的弊端,提出了一种基于数字孪生预测性维护的一般模式,并基于数字孪生技术,构建空气预热器数字孪生系统。【方法】所提系统包括回转式空气预热器物理实体、实时数据采集与分析模块、数字孪生模型构建模块、热力参数状态监测、转子热场视频与热变形可视化及积灰预测模块;实时采集温度参数状态和视频数据,通过温度场、视频图像、漏风计算等模块,实现热力参数的计算并进行积灰的预测。同时,以3D组态画面实时显示数据,利用软件算法不断优化热力参数计算及积灰预测的准确度,实现吹灰策略自动优化。【结果】所提方案实现了空气预热器热力计算过程的状态监测与动态控制,解决现有电站中回转式空气预热器积灰因素影响火电机组安全可靠运行的问题。【结论】通过实际机组的工程测试,所提方案有效提高了火电机组空气预热器运行维护的效率,验证了所提方法的可行性,为后期智慧电厂系统的开发提供技术支撑。

关键词：火电机组预防性维护预测性维护数字孪生空气预热器