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Unlocking G-Quadruplexes as Targets and Tools against COVID-19

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Chinese Journal of Chemistry 2023年第5期41卷 560-568页

作者： geng Qin Chuanqi zhao jie Yang zhao Wang Jinsong Ren Xiaogang Qu Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry ChineseAcademyof ScienceChangchunJilin 130022 University of Science and Technology of China HefeiAnhui 230026China

The applicability of G-quadruplexes(G4s)as antiviral targets,therapeutic agents and diagnostic tools for coronavirus disease 2019(COVID-19)is currently being evaluated,which has drawn the extensive attention of the scientific *** the COVID-19 pandemic,research in this field is rapidly *** this review,we summarize the latest achievements and breakthroughs in the use of G4s as antiviral targets,therapeutic agents and diagnostic tools for COVID-19,particularly using G4 ***,strength and weakness regarding G4s in anti-SARS-CoV-2 field are highlighted for prospective future projects.

关键词： G-quadruplexes Viruses Nucleic acids Drug discovery Aptamers

Novel Hash Function Based on Coupled Chaotic Map Lattices

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Chinese Journal of Electronics 2014年第4期23卷 836-841页

作者： ZHEN Ping zhao geng MIN Lequan LI Xiaodong School of Automation and Electrical Engineering University of Science and Technology Beijing Beijing Electronic Science and Technology Institute School of Mathematics and Physics University of Science and Technology Beijing

Hash function has been widely used in cryptographic field. This paper proposes a Hash function based on complexly Coupled chaotic map latices(CCML).It is equipped with new features of parallel and flexible processing. Parallelism indicates that the algorithm can reach high level of efficiency and speed. Flexibility means the length of Hash function and message block processed each time can be easily changed to adapt to practical demand. Experimental results show that the Hash function is one-way, with high plaintext sensitivity, as well as its strong capability for confusion and diffusion, and collision resistance. In comparison with MD5 and another Hash function based on chaos, the proposed Hash function shows good performance.

关键词： Hash function Parallelism Flexibility Coupled chaotic map lattice

Non-directed highly para-selective C-H functionalization of TIPS-protected phenols promoted by a carboxylic acid ligand

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Chinese Chemical Letters 2023年第3期34卷 342-346页

作者： Jingyao geng Zhang Fang Guangliang Tu yingsheng zhao Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453000China

Palladium-catalyzed non-directed C-H functionalization provides an efficient approach for direct functionalization of arenes, but it usually suffers from poor site selectivity, limiting its wide ***, it is reported for the first time that the carboxylic acid ligand of 3,5-dimethyladamantane-1-carboxylic acid(1-DMAd CO_(2)H) can affect the site selectivity during the C-H activation step in palladiumcatalyzed non-directed C-H functionalization, leading to highly para-selective C-H olefination of TIPSprotected phenols. This transformation displayed good generality in realizing various other para-selective C-H functionalization reactions such as halogenation, and allylation reactions. A wide variety of phenol derivatives including bioactive molecules of triclosan, thymol, and propofol, were compatible substrates,leading to the corresponding para-selective products in moderate to good yields. A preliminary mechanism study revealed that the spatial repulsion factor between carboxylic acid ligand and bulky protecting group resulted in the selective C-H activation at the less sterically hindered para-position. This new model non-directed para-selective C-H functionalization can provide a straightforward route for remote site-selective C-H activations.

关键词： para-Selective Non-directed C-H olefination

Design study of APS-U-type hybrid-MBA lattice for mid-energy DLSR

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Nuclear Science and Techniques 2021年第7期32卷 46-54页

作者： Yu zhao yi Jiao Sheng Wang Institute of High Energy Physics(IHEP) Chinese Academy of Sciences(CAS)Beijing 100049China University of Chinese Academy of Sciences(UCAS) Beijing 100049China Spallation Neutron Source Science Center(SNSSC) Dongguan 523803China

In recent years,a new generation of storage ring-based light sources,known as diffraction-limited storage rings(DLSRs),whose emittance approaches the diffraction limit for the range of X-ray wavelengths of interest to the scientific community,has garnered significant attention *** have begun to design and build *** various DLSR proposals,the hybrid multibend achromat(H-MBA)lattice enables sextupole strengths to be maintained at a reasonable level when minimizing the emittance;hence,it has been adopted in many DLSR *** on the H-7BA lattice,the design of the Advanced Photon Source Upgrade Project(APS-U)can effectively reduce emittance by replacing six quadrupoles with ***,we discuss the feasibility of designing an APS-U-type H-MBA lattice for the Southern Advanced Photon Source,a mid-energy DLSR light source with ultralow emittance that has been proposed to be built adjacent to the China Spallation Neutron *** linear and nonlinear dynamics are optimized to obtain a detailed design of this type of *** emittance is minimized,while a sufficiently large dynamic aperture(DA)and momentum acceptance(MA)are maintained.A design comprising 36 APS-U type H-7BAs,with an energy of 3 GeV and a circumference of 972 m,is *** horizontal natural emittance is 20 pm·rad,with a horizontal DA of 5.8 mm,a vertical DA of 4.5 mm,and an MA of 4%,as well as a long longitudinal damping time of 120 ***,a few modifications are performed based on the APS-U-type lattice to reduce the maximum value of damping time from 120 to 44 ms while maintaining other performance parameters at the same level.

关键词： Southern advanced photon source(SAPS) Diffraction-limited storage ring(DLSR) Hybrid multibend achromat(H-MBA) Advanced photon source upgrade project(APS-U) Lattice design

Current strategies for preventing the recurrence of hepatocellular carcinoma after liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2015年第2期14卷 145-149页

作者： Zhuo-yi Wang Lei geng Shu-Sen Zheng Key Laboratory of Combined Multi-organ Transplantation Ministry of Public Health Division of Hepatobiliary and Pancreatic Surgery First Affiliated Hospital Zhejiang University School of Medicine Division of Hepatobiliary and Pancreatic Surgery First Affiliated Hospital Zhejiang University School of Medicine

BACKGROUND：Liver transplantation is the optimal treatment for a selected group of patients with moderate to severe cirrhosis and hepatocellular carcinoma（HCC）.Despite the strict selection of candidates,post-transplant recurrence often occurs and markedly reduces the long-term survival of patients with *** present review focuses on the current strategies on preventing the recurrence of HCC after liver *** SOURCES： Relevant articles were identified by exten- sive searching of PubMed using the keywords ＂hepatocellular carcinoma＂, ＂recurrence＂ and ＂liver transplantation＂ between January 1996 and January 2014. Additional papers were searched manually from the references in key articles. RESULTS： The current theories of HCC recurrence after liver transplantation are：（i） the growth of pre-transplant occult metastases; （ii） the engraftment of circulating tumor cells released at the time of transplantation. Pre-transplant treatment aims to control local tumor by radiofrequency ablation, transarterial embolization and transarterial chemoembolization. The main objective during the operation is to prevent tumor cell dissemination. Post-transplant treatment includes systemic anticancer therapy, antiviral therapy, and most recently, immunotherapy. These strategies concentrate on the control of the tumor when the patients are waiting for transplant, to reduce the release of HCC cells during surgical procedures and to dear the occult HCC cells after ***： Much can be done to prevent HCC recurrence after liver transplantation. In future, effort is likely to be di- rected towards combining multidisciplinary approaches and various treatment modalities.

关键词： hepatocellular carcinoma recurrence liver transplantation

Design of a CMOS Distributed Power Amplifier with Gradual Changed Gain Cells

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Chinese Journal of Electronics 2018年第6期27卷 1158-1162页

作者： ZHANG ying LI Zeyou YANG Hua geng Xiao ZHANG yi College of Electronic and Optical Engineering College of Microelectronics Nanjing University of Posts and Telecommunications National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing University of Posts and Telecommunications

A non-uniform Distributed power amplifier(DPA) is designed and implemented in a 0.18μm CMOS technology. The gradual changed gain cells work with the tapered on-chip inductors to construct non-uniform artificial transmission lines, which improves the output power and efficiency in a wide frequency band while maintaining good input and output impedance matching. The proposed DPA achieves 9 dB average associated gain from 1 to 17.2 GHz, and the input return loss is less than--9 dB while the output return loss is less than-8.5 dB in the desired frequency band. The output power at 1 dB Output compression point(OP1 dB) is more than 7.8 dBm in the frequency band of 2-16 GHz, and the peak power-added efficiency is 6.2% with the OP1 dB12.6 dBm at 4 GHz.

关键词： Distributed amplifier Impedance matching Power added efficiency Artificial transmission line

Observer-based multi-objective parametric design for spacecraft with super flexible netted antennas

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Science China(Information Sciences) 2020年第7期63卷 161-181页

作者： Guang-Ren DUAN Tian-yi zhao Center for Control Theory and Guidance Technology Harbin Institute of Technology

A multi-objective parametric design method that based on the robust observer is proposed for the attitude control of satellites with super flexible netted antennas. First, a parametric observer-based controller is obtained based on the eigen-structure assignment theory. The closed-loop poles are assigned to desired positions or regions, and full degrees of freedom of the design, which are characterized by a set of parameters, are preserved under the proposed control law. Second, the obtained parameters are comprehensively optimized to make the closed-loop system have lower eigenvalue sensitivity, a smaller control gain, and stronger tolerance to high-order unmodeled dynamics and external disturbances. Finally, comparative simulations are carried out based on practical engineering parameters of a satellite in order to verify the effect of the proposed method, and also to show their superiority over the traditional proportional-integral-derivative(PID) controller with filters and the traditional dynamic compensators.

关键词： parametric design of control systems multi-objective designs robust observers super flexible spacecraft parameter perturbations high-order flexible modes

Non-volatile constituents and pharmacology of Chimonanthus: A review

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Chinese Journal of Natural Medicines 2019年第3期17卷 161-186页

作者： SHU Ren-geng WAN yi-Li WANG Xiao-Min School of Pharmacy Jiangxi University of Traditional Chinese Medicine School of Pharmacy China Pharmaceutical University School of Life Science Jiangxi University of Traditional Chinese Medicine

Chimonanthus plants widely distributed in southern area of China, which have a long history of edibles and medicine. Phytochemical investigations have shown that Chimonanthus produced 143 non-volatile constituents, including alkaloids, flavonoids, terpenoids, coumarins and others, which exhibit significant anti-oxidant, anti-bacterial, anti-cancer, anti-inflammatory, antihyperglycemic, antihyperlipidemic and other biological activities. On the basis of systematic reviewing of literatures, this article overviews the non-volatile constituents and pharmacology of Chimonanthus from domestic and foreign over the last 30 years(until June 2018), and may provide a useful reference for the further development of Chimonanthus.

关键词： Chimonanthus Non-volatile constituents Pharmacology Review

Scheme for generating 1 nm X-ray beams carrying orbital angular momentum at the SXFEL

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Nuclear Science and Techniques 2020年第9期31卷 33-44页

作者： He-Ping geng Jian-Hui Chen Zhen-Tang zhao Chinese Academy of Sciences Shanghai Institute of Applied PhysicsShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Chinese Academy of Sciences Shanghai Advanced Research InstituteShanghai 201210China

Optical vortices have the main features of helical wavefronts and spiral phase structures,and carry orbital angular *** special structure of visible light has been produced and studied for various *** notable characteristics of photons were also tested in the extreme-ultraviolet and X-ray *** this article,we simulate the use of a simple afterburner configuration by directly adding helical undulators after the SASE undulators with the Shanghai Soft X-ray FEL to generate high intensity X-ray vortices with wavelengths^1 *** to other methods,this approach is easier to implement,cost-effective,and more efficient.

关键词： X-ray Orbital angular momentum(OAM) Synchrotron light source Free-electron laser(FEL)