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Gene delivery into isolated Arabidopsis thaliana protoplasts and intact leaves using cationic, a-helical polypeptide

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 521-528页

作者： Zheng, Nan song, ziyuan Liu, Yang Cheng, Jianjun Yin, Lichen Univ Illinois Dept Mat Sci & Engn Urbana IL 61801 USA Dalian Univ Technol Sch Chem Engn Dept Polymer Sci & Engn State Key Lab Fine Chem Dalian 116024 Peoples R China Soochow Univ Inst Funct Nano & Soft Mat FUNSOM Jiangsu Key Lab Carbon Based Funct Mat & Devices Collaborat Innovat Ctr Suzhou Nano Sci & Technol Suzhou 215123 Peoples R China

The application of gene delivery materials has been mainly focused on mammalian cells while rarely extended to plant engineering. Cationic polymers and lipids have been widely utilized to efficiently deliver DNA and siRNA into mammalian cells. However, their applica- tion in plant cells is limited due to the different membrane structures and the presence of plant cell walls. In this study, we developed the cationic, a-helical polypeptide that can effectively deliver DNA into both isolated Arabidopsis thaliana protoplasts and intact leaves. The PPABLG was able to condense DNA to form nanocomplexes, and they exhibited significantly improved transfection efficiencies compared with commercial transfection reagent Lipofec- tamine 2000 and classical cell penetrating peptides such as poly（L-lysine）, HIV-TAT, arginine9, and poly（L-arginine）. This study therefore widens the utilities of helical polypeptide as a unique category of gene delivery materials, and may find their promising applications toward plant gene delivery.

关键词： a-helical polypeptide plant gene delivery,protoplast intact leaves transfection

Accelerated Ring-Opening Polymerization of α-Amino Acid N-Carboxyanhydride via Inorganic Nano-initiators

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Chinese Journal of Chemistry 2023年第19期41卷 2476-2482页

作者： Junliang Zhu Yunjie He Chenglong Ge Wenting Si ziyuan song Lichen Yin Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhouJiangsu215123 China

While the accelerated polymerization of N-carboxyanhydrides (NCAs) has been utilized to synthesize versatile polypeptide materials in an efficient manner with minimized side reactions, the preparation of polypeptide-based inorganic/organic hybrid materials with the acceleration strategy remained largely unexplored. Herein, we report the accelerated ring-opening polymerization (ROP) of NCAs mediated by amine-modified inorganic nano-initiators, such as mesoporous silica nanoparticles (MSN-NH2), which is driven by the cooperative effect of the neighboring α-helical polypeptide chains in a dichloromethane (DCM)/water biphasic system. Well-defined nano-hybrids were prepared within 15 min from non-purified NCA monomers, through in situ purification and subsequent ultrafast polymerization process. NCAs can be rapidly initiated by amino groups of MSN uniformly dispersed at the interface of DCM and water, and subsequently formed the well-defined polypeptides within 15 min. The prepared inorganic/organic nano-hybrid with MSN as the core and polypeptide as the shell adopted spherical morphology and uniform size distribution due to the excellent controllability of ROP. Besides, this system is also suitable for a variety of NCAs and inorganic nano-initiators. This research allows efficient and rapid preparation of inorganic/organic nano-hybrids, and further promotes the extensive application of this material in the biomedical fields.

关键词： Polypeptide N-Carboxyanhydride Inorganic organic nano-hybrids Cooperative covalent polymerization Ring-opening polymerization Kinetics Synthetic methods

Models and performance of SBAS and PPP of BDS

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Satellite Navigation 2022年第1期3卷 60-73,I0003页

作者： Junping Chen Yize Zhang Chao Yu Ahao Wang ziyuan song Jianhua Zhou Shanghai Astronomical Observatory Chinese Academy of SciencesBeijingChina School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China College of Geoscience and Surveying Engineering China University of Mining and Technology-BeijingBeijing 100083China Beijing Satellite Navigation Center BeijingChina.

Satellite Based Augmentation System(SBAS)is one of the services provided by the BeiDou Navigation Satellite System(BDS).It broadcasts four types of diferential corrections to improve user application *** corrections include the State Space Representation(SSR)based satellite orbit/clock corrections and ionospheric grid corrections,and the Observation Space Representation(OSR)based partition comprehensive *** algorithms generating these SBAS corrections are not introduced in previous researches,and the user SBAS positioning performance with the contribution of BDS-3 has not been *** this paper,we present the BDS SBAS algorithms for these diferential corrections in *** types of Precise Point Positioning(PPP)function models for BDS Dual-Frequency(DF)and Single-Frequency(SF)users using the OSR and SSR parameters are also *** week of data in 2020 is collected at 20 reference stations including the observations of both BeiDou-2 Navigation Satellite System(BDS-2)and BeiDou-3 Navigation Satellite System(BDS-3)satellites,and the PPP under various scenarios are performed using all the datasets and the BDS SBAS broadcast *** results show that the performance of BDS-2/BDS-3 combination is superior to that of BDS-2 only *** positioning errors in Root Mean Square(RMS)for the static DF PPP are better than 8 cm/15 cm in horizontal/vertical directions,while for the static SF PPP are 11 cm/24 *** the scenarios of simulated kinematic PPP,three Dimension(3D)positioning errors can reach 0.5 m in less than 10 min for the DF PPP and 30 min for the SF PPP,and the RMSs of the DF and SF PPP are better than 17 cm/21 cm and 20 cm/32 cm in horizontal/vertical *** a real-time single-and dual-frequency kinematic positioning test,the positioning errors of all three components can reach 0.5 m within 30 min,and the positioning accuracy after solution convergence in the N,E and U directions is better than 0.3 m.

关键词： SBAS BDS State Space Representation(SSR) Observation Space Representation(OSR) Precise point positioning

Modulation of polymerization rate of N-carboxyanhydrides in a biphasic system

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Chinese Chemical Letters 2024年第1期35卷 326-331页

作者： Guonan Ji Xuetao Zheng Xiangdie Hou Xiao Sun Shijie Wang Xiaohong Li Jianjun Cheng ziyuan song Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123China Research Center for Industries of the Future Westlake UniversityHangzhou 310030China School of Engineering Westlake UniversityHangzhou 310030China The Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

The recent advances in accelerated polymerization of N-carboxyanhydrides (NCAs) offer an effective strategy to simplify the preparation of polypeptide materials. However, the fine-tuning of polymerization kinetics, which is critical to differentiate the main polymerization and the side reactions, remains largely unexplored. Herein we report the modulation of polymerization rate of NCA in a water/oil biphasic system. By altering the aqueous pH, the initial location of the initiators, and the pK_(a) of initiating amines, we observed the change in polymerization time from several minutes to a few hours. Due to the high interfacial activity and low pKa value, controlled polymerization was observed from multi-amine initiators even if they were initially located in the aqueous phase. This work not only improves our understanding on the biphasic polymerization mechanism, but also facilitates preparation of versatile polypeptide materials.

关键词： N-Carboxyanhydrides Polypeptides Biphasic system Cooperative covalent polymerization Polymerization kinetics

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Nanoengineered polypeptides from tetraphenylethylene-functionalized N-carboxyanhydride: Synthesis, self-assembly and intrinsic aggregation-induced emission

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Progress in Natural Science:Materials International 2021年第4期31卷 541-545页

作者： Xu Wang Zihao Zhao Tianrui Xue Zhengzhong Tan ziyuan song Shiqi Wei Yang Bo Ying Wang Jianjun Cheng Department of Materials Science and Engineering University of Illinois at Urbana-Champaign Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics (Theranostics) School of Pharmacy Tianjin Medical University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University

Ring-opening polymerization of N-carboxyanhydrides(NCAs) bearing pendant groups creates functional polypeptides. In this paper, we report the design, synthesis and polymerization of tetraphenylethylene(TPE)-modified NCA, which is used to incorporate aggregation-induced emission(AIE)-active segments into polypeptides. Specifically, we attempted the synthesis of amphiphilic methoxy poly(ethyleneglycol)-block-poly(γ-benzyl-L-glutamate)-block-poly(γ-4-(1,2,2-triphenylvinyl)benzyl-L-glutamate)(PEG-PBLG-PTPELG), which had well-controlled molecular weight and narrow polydispersity. The hydrophilic PEG and hydrophobic PBLG-PTPELG assembled into micelles in aqueous solution with diameter around 70 nm, displaying AIE at 480 nm. Our work demonstrates that the TPE-modified NCA is applicable for the preparation of the AIE-active polypeptides, integrating the AIE luminogens into the polypeptides which may offer unique opportunities for tuning AIE properties by adjusting the composition and conformation of polypeptides. We preliminarily explored the use of the amphiphilic polypeptides for the formulation of doxorubicin-containing micelles that can potentially be used for real-time monitoring of the nanomedicine distribution.

关键词： N-carboxyanhydride Ring-opening polymerization Polypeptide Micelle Aggregation-induced emission

Analysis and Modeling of the Inter-System Bias Between BDS-2 and BDS-3

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Analysis and Modeling of the Inter-System Bias Between BDS-2...

有形与无形之手能否协同激发城市创新活力——基于中国275个城市数据的分析

第十一届中国卫星导航年会

作者： ziyuan song Junping Chen Bin Wang Chao Yu Shanghai Astronomical Observatory Chinese Academy of Science University of Chinese Academy of Science

The BDS-3 system has provided positioning navigation and timing(PNT) service since December 2018,while applications show that there is intersystem bias(ISB) between the BDS-2 and BDS-3 ***

关键词： BDS-2 BDS-3 inter-system bias standard point positioning precise point positioning

来源： cnki会议 cnki会议 cnki会议评论

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科技进步与对策 2023年第6期40卷 59-68页

作者：吕慧许可宋子源中国财政科学研究院北京100142 山东大学国际创新转化学院山东青岛266237 山东大学管理学院山东济南250103

基于2012-2020年我国275个城市面板数据,分析财政科技支出、数字普惠金融对城市创新的影响机制,并检验空间效应的有效性。研究发现:①财政科技支出、数字普惠金融均可提升本地创新水平;②财政科技支出、数字普惠金融对城市创新均产生显... 详细信息

基于2012-2020年我国275个城市面板数据,分析财政科技支出、数字普惠金融对城市创新的影响机制,并检验空间效应的有效性。研究发现:①财政科技支出、数字普惠金融均可提升本地创新水平;②财政科技支出、数字普惠金融对城市创新均产生显著的空间溢出效应,但二者存在一定的抵消,财政科技支出在推动本地创新的同时也能够带动其它关联地区的创新发展,数字金融的普惠性发展虽然可激励本地创新,但对其它关联城市的创新发展有一定抑制性;③数字普惠金融发展弱化了财政科技资金的创新效应,即财政科技支出和数字普惠金融二者对城市创新的驱动作用存在替代效应,且替代效应具有明显的地区差异。基于此,有针对性地提出政策建议,为激发城市创新活力提供有益参考。

关键词：财政科技支出数字普惠金融城市创新空间溢出效应替代效应

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爱尔兰岛高比例新能源电力系统运行经验与启示

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电网技术 2024年第2期48卷 498-508页

作者：闫景皓黄越辉卢慧宋子源李湃可再生能源并网全国重点实验室(中国电力科学研究院有限公司) 北京市海淀区100192

随着全球能源转型步伐的加快,世界各国电力系统均大力发展以风电和光伏发电为主的新能源。爱尔兰岛电力系统为岛屿独立同步电网,具有新能源渗透率高、与外部电网交互功率小等特点。经过长期摸索与发展,爱尔兰岛高比例新能源电力系统运... 详细信息

随着全球能源转型步伐的加快,世界各国电力系统均大力发展以风电和光伏发电为主的新能源。爱尔兰岛电力系统为岛屿独立同步电网,具有新能源渗透率高、与外部电网交互功率小等特点。经过长期摸索与发展,爱尔兰岛高比例新能源电力系统运行水平处于世界前列,其先进经验对我国新型电力系统建设具有重要借鉴意义。介绍了爱尔兰岛电力工业的概况,分析了爱尔兰岛电力系统的运行情况,探究了爱尔兰岛电力公司为保证高比例新能源电力系统安全高效运行采取的措施,最后总结其对我国新型电力系统建设的经验与启示。

关键词：爱尔兰电力系统新能源 SNSP 运行经验

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流量劫持行为刑法规制再思考

上海公安学院学报 2021年第4期31卷 58-66,89页

作者：宋梓源华东政法大学刑事法学院上海200042

流量劫持行为是新类型计算机犯罪,以流量劫持行为为核心已经衍生出庞大的黑灰产业链。根据流量劫持类型的不同,可以将其划分为域名劫持和链路劫持。流量劫持带来的刑事风险威胁有着多元化的法益,以刑事手段规制具有必要性和优势性。实... 详细信息

流量劫持行为是新类型计算机犯罪,以流量劫持行为为核心已经衍生出庞大的黑灰产业链。根据流量劫持类型的不同,可以将其划分为域名劫持和链路劫持。流量劫持带来的刑事风险威胁有着多元化的法益,以刑事手段规制具有必要性和优势性。实践中对流量劫持行为定性存在争议,主要围绕如何认定破坏计算机信息系统罪和非法控制计算机信息系统罪。为厘清两个罪名的关系,应将"非法控制"解释为非排他性的破坏行为,并以阶层式的思维对这两个罪名进行理解适用。

关键词：流量劫持刑事风险破坏计算机信息系统罪非法控制计算机信息系统罪

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