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Truncated gRNA reduces CRISPR/Cas9-mediated off-target rate for MSTN gene knockout in bovines

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Journal of Integrative Agriculture 2019年第12期18卷 2835-2843页

作者： ZHOU zheng-wei CAO Guo-hua LI Zhe HAN Xue-jie LI Chen lu zhen-yu ZHAO yu-hang LI Xue-ling State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestocks/Research Center for Laboratory Animal Science Inner Mongolia University

The CRISPR/Cas9 mediates efficient gene editing but has off-target effects inconducive to animal breeding. In this study, the efficacy of CRISPR/Cas9 vectors containing different lengths of g RNA in reduction of the off-target phenomenon in the bovine MSTN gene knockout fibroblast cell lines was assessed, providing insight into improved methods for livestock breeding. A 20-bp g RNA was designed for the second exon of the bovine MSTN gene, and CRISPR/Cas9-B was constructed to guide the Cas9 protein to the AGAACCAGGAGAAGATGGACTGG site. The alternative CRISPR/Cas9-19, CRISPR/Cas9-18, CRISPR/Cas9-17 and CRISPR/Cas9-15 vectors were constructed using g RNAs truncated by 1, 2, 3 and 5 bp, respectively. These vectors were then introduced into bovine fetal fibroblasts by the electroporation method, and single cells were obtained by flow cytometry sorting. PCR was performed for each off-target site. All samples were sequenced and analyzed, and finally the efficiency of each vector in target and off-target sites was compared. The CRISPR/Cas9-B vector successfully knocked out the MSTN gene, but the off-target phenomenon was observed. The efficiencies of CRISPR/Cas-B, CRISPR/Cas9-19, CRISPR/Cas9-18, CRISPR/Cas9-17 and CRISPR/Cas9-15 in triggering gene mutations at MSTN targeting sites were 62.16, 17.39, 7.69, 74.29 and 3.85%, respectively;rates of each at the Off-MSTN-1 locus were 52.86, 0, 0, 8.82 and 0%, respectively;all were 0% at the Off-MSTN-2 locus;rates at the Off-MSTN-3 site were 44.87, 51.72, 86.36, 0 and 50%, respectively. The efficiency of the CRISPR/Cas9-17 plasmid in the MSTN site was higher than that in the CRISPR/Cas9-B plasmid, and the effect at the three off-target sites was significantly lower. This study demonstrated that the CRISPR/Cas9-17 plasmid constructed by truncating 3 bp g RNA can effectively reduce the off-target effect without reducing the efficiency of bovine MSTN gene targeting. This finding will provide more effective gene editing strategy for use

关键词： CRISPR/Cas9 gRNA targeting site off-target rate

COMPLEX NUMBER MODE APPROACH FOR REDUCING VIBRATION OF STRUCTURAL FLEXIBLE REDUNDANT ROBOT MANIPULATORS

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Chinese Journal of Mechanical Engineering 2001年第2期14卷 102-105页

作者： Wu Licheng Sun Zengqi Sun Fuchun Department of Computer Science and Technology, Qinghua University lu zhen yu Shouqian zheng Hong Beijing University of Aeronautics and Astronautics 清华大学计算机科学与工程系北京北京航空航天大学北京

A complex number mode analysis approach is proposed for vibration reducing of structural flexible redundant manipulators by utilizing self motion. In the proposed approach, the self motion is evaluated to nullify the modal exciting force of flexural motion, and the approach can be freely used when the degree of freedom of flexural motion is much greater than the available degree of reundancy. The availability and effectiveness of the proposed approach are demonstrated through numerical simulation with a four link spatial robotic manipulator possessing an end flexible link.

关键词： Redundant manipulators Self motion Vibration reducing Complex number mode analysis

Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro Letters 2025年第2期17卷 548-565页

作者： Ming‑yuan yu Jing Wu Guang Yin Fan‑zhen Jiao Zhong‑zhen yu Jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods

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异步轧制铜/铝复合板界面结合强度研究

塑性工程学报 2019年第4期26卷 93-97页

作者：吕震宇山东职业学院铁道车辆与机械工程系

对不同异步速比条件下铜/铝复合板界面结合强度和剥离形貌进行了研究,分析了轧制变形区界面正应力、剪切应力以及等效应变对复合板结合强度的影响机制。结果表明:随异步速比的增加,铜/铝复合板界面的剥离强度先增大后减小,且在异步速比... 详细信息

对不同异步速比条件下铜/铝复合板界面结合强度和剥离形貌进行了研究,分析了轧制变形区界面正应力、剪切应力以及等效应变对复合板结合强度的影响机制。结果表明:随异步速比的增加,铜/铝复合板界面的剥离强度先增大后减小,且在异步速比为1.15时达到最大值34.2 N·mm-1。从剥离形貌来看,异步速比为1.15时复合板剥离界面上黏着的铝脊数量和面积达到最大,且异步速比大于1.15时,剥离面黏着的铝屑明显增加。模拟结果分析发现:随着异步速比的增加,界面处的等效应变和剪切应力均逐渐增大,可有效促进金属间的结合效果。当异步速比大于1.15时,轧制变形区出口侧的剪切应力急剧上升,对结合界面造成一定的破坏作用,因此复合板的剥离强度随异步速比的增加,呈先上升后迅速下降的变化趋势。

关键词：异步轧制异步速比剥离强度结合强度剥离形貌

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耦合多新息随机梯度辨识方法性能分析

控制与决策 2015年第8期30卷 1527-1530页

作者：鹿振宇黄攀峰西北工业大学航天学院西安710072 西北工业大学航天飞行动力学技术重点实验室西安710072

针对一类耦合参数多变量系统,提出一种耦合多新息随机梯度方法.通过该方法进行参数辨识并对该方法进行性能分析.该方法的基本思路在于利用历史新息中包含的信息,将耦合随机梯度算法中的新息项扩展为多新息向量,从而提升耦合随机梯度算... 详细信息

针对一类耦合参数多变量系统,提出一种耦合多新息随机梯度方法.通过该方法进行参数辨识并对该方法进行性能分析.该方法的基本思路在于利用历史新息中包含的信息,将耦合随机梯度算法中的新息项扩展为多新息向量,从而提升耦合随机梯度算法中单个子系统的辨识效果.仿真结果表明,通过增加新息长度可以提升辨识结果的收敛速度和精度.

关键词：参数估计多变量系统耦合随机梯度多新息向量收敛性分析

Alteration of retinol binding protein 4 in preeclampsia during and 6 weeks after pregnancy

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Alteration of retinol binding protein 4 in preeclampsia duri...

Research on the appropriate way to transfer exogenous substances into chicken embryos

2011中国妇产科学术会议暨浙江省计划生育与生殖医学学术年会暨生殖健康讲习班

作者： lu Qi,ZHANG zhen-yu Beijing Chaoyang Hospital

Objective Our study was to investigate serum and placental levels of the novel adipokine retinol-binding protein 4 (RBP4) in patients with preeclampsia as compared with healthy controls and six weeks after delivery. Methods We investigated serum concentrations of RBP4 by ELISA in control and preeclampsia patients during pregnancy(non-pregnant women=40,normal pregnant=40,preeclampsia=69) and six weeks after delivery(control=50,

关键词：

来源： cnki会议评论

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Journal of Integrative Agriculture 2017年第10期16卷 2257-2263页

作者： WANG Yi-lin JIN Kai HE Na-na CHENG Shao-ze ZUO Qi-sheng LI Dong WANG Ying-jie WANG Fei JI Yan-qing lu zhen-yu ZHANG Chen WANG Man ZHAO Rui-feng yu Xin-jian ZHANG Ya-ni ZHAO Wen-ming LI Bi-chun College of Animal Science and Technology/Jiangsu Province Key Laboratory of Animal Breeding and Molecular Design Yangzhou University Yangzhou 225009 P.R.China

In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation. Transferring exogenous substances into chicken embryos for producing medical antibodies has been widely used in the production practice. However, there are few studies about the effect of the different injection site and dosage on chicken embryos. The aim of this study was to explore the effects of different injection sites and dosages on chicken embryo hatching rate and development, so as to provide a basis for further studies using the chicken embryo model. Freshly laid eggs （Rugao yellow chicken） were injected with different doses of saline at the tip, equatorial plane and the blunt end of the egg shell, respectively. Egg hatching rate was recorded and compared among injection sites and different doses. A trypan blue stain was also injected at the aforementioned sites and the growth of chicken embryos was observed. The SPSS （statistical package for the social science） software was used to analyze the relationship between the chicken eggs hatching rate and the different injection sites or the different dosages. The experimental results showed that there were significant differences on egg hatching rates among the different injection sites and doses （P〈0.05）. The hatchability of the blunt end injection group was significantly higher than that of the other two sites. The egg hatching rate decreased with increased saline doses. The egg hatching rate of the 100 pL saline injection group was higher than the 200 and 300 μL dosage groups. Ultimately, we suggest that the optimal chicken embryo injection process is during early development, at the blunt end site with a dose less than 100 μL to minimize damage to the egg.

关键词： chicken embryos injection dosage hatchability chick embryo development

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基于推荐的信任链管理模型

通信学报 2011年第10期32卷 1-9页

作者：田俊峰鲁玉臻李宁河北大学数学与计算机学院河北保定071002

针对目前信任链管理中信任计算时信任信息不完备的问题,提出了一种基于推荐的信任链管理模型RTCM(recommendation based trust chain management model)。通过构建信任网络,在信任链选择时考虑信任传递衰减、时间衰减、路径权重等因素,... 详细信息

针对目前信任链管理中信任计算时信任信息不完备的问题,提出了一种基于推荐的信任链管理模型RTCM(recommendation based trust chain management model)。通过构建信任网络,在信任链选择时考虑信任传递衰减、时间衰减、路径权重等因素,使得信任链搜索的时间复杂度大幅降低。充分包含了信任的相关信息,并利用加权紧密度对信任链上的推荐信任进行合并,同时给出了抑制节点恶意推荐的策略。仿真实验表明,该模型提高了网络的可信性。

关键词：信任推荐信任加权紧密度推荐合并

Integration of Electrical Properties and Polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 517-532页

作者： Kaili Zhang yuefeng Yan zhen Wang Guansheng Ma Dechang Jia Xiaoxiao Huang yu Zhou State Key Laboratory of Precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China MIIT Key Laboratory of Advanced Structural‑Functional Integration Materials&Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)*** on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is considered a feasible ***,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,Co,Ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-coordination atom-assisted *** composites had adjustable conductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA *** results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.Combined with X-ray absorption spectra(XAFS),atomic force microscopy,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural ***,electron migration within the Fe further leads to conduction loss,thereby synergistically promoting energy *** study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism.

关键词： Electromagnetic wave absorption Fe-N-RGO Dipole polarization Conduction loss Impedance matching