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Dual-imaging-mode smart hydrogel information platform for illumination-independent covert decryption and read

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International Journal of Smart and Nano Materials 2022年第4期13卷 612-625页

作者： junjie wei Long Li Rui Li Qingquan Liu Zejun Yan Tao Chen Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingboChina School of Chemical Sciences University of Chinese Academy of SciencesBeijingChina Hunan Provincial Key Laboratory of Advanced Materials for New Energy Storage and Conversion Hunan University of Science and TechnologyXiangtanChina Department of Urology&Nephrology Ningbo First Hospitalthe Affiliated Hospital of Zhejiang UniversityNingboChina

Smart hydrogel with color responsiveness is envisioned as one of the most promising materials for advanced information encryption and decryption platform,but the illumination-dependent way of decrypt-ing and reading information leads to the worrying of concealment in some particular scenarios.Herein,we proposed a smart hydrogel information platform with dual imaging modes by utilizing the accom-panying behaviors in transparency change and heat releasing after crystallization of supercooled solution.For this smart hydrogel informa-tion platform,the hidden information could be written and decrypted by ink of ethylene glycol and decryption tool of seed crystal,respec-tively.Furthermore,in addition to the traditional optical imaging mode with the assistance of light illumination,the decrypted information on dual-imaging-mode hydrogel platform also could be read by thermal imaging mode in dark environment owing to the exothermic crystal-lization.The illumination-independent read mode based on heat radia-tion helps to improve the secrecy and safety of the decryption and read process.This investigation provides a facile and feasible strategy to design illumination-independent information platform that enables reading the encrypted information in secret.

关键词： Hydrogel information platform information decryption thermal imaging illumination-independent pattern crystallization

Dynamics of an infection model with two delays

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International Journal of Biomathematics 2015年第5期8卷 295-315页

作者： Xinguo Sun junjie wei ＊Department of MathematicsHarbin Institute of Technology Harbin Heilongjiang 150001 P. R. China School of ScienceChina University of Petroleum (East China) Qingdao 266580 P. R. China

In this paper, a HTLV-I infection model with two delays is considered. It is found that the dynamics of this model are determined by two threshold parameters R 0 and R 1 , basic reproduction numbers for viral infection and for CTL response, respectively. If R 0 1, there exists a unique HAM/TSP equilibrium P 2 . The stability of P 2 is changed when the second delay τ 2 varies, that is there exist stability switches for P 2 .

关键词：病毒感染模型延迟动力学全局渐近稳定无病平衡点稳定性再生数

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人民币汇率变动对中国进出口贸易的影响分析

新金融 2024年第1期 15-22,30页

作者：管涛魏俊杰中银证券

本文研究人民币汇率变动对中国进出口贸易的影响机制,测算中国进出口贸易弹性并估计J曲线效应。结果显示,人民币汇率变动在短期内对于调节进出口贸易及其差额的作用有限。相较于汇率变动,外需对于出口金额的影响程度更大,内需和大宗商... 详细信息

本文研究人民币汇率变动对中国进出口贸易的影响机制,测算中国进出口贸易弹性并估计J曲线效应。结果显示,人民币汇率变动在短期内对于调节进出口贸易及其差额的作用有限。相较于汇率变动,外需对于出口金额的影响程度更大,内需和大宗商品价格对于进口金额影响更大,表明进出口贸易的收入效应远大于汇率的价格效应。此外,汇率变动对进出口贸易收支变动的时滞约为一年,双边汇率的J曲线效应更为显著,这与中国进出口计价结算中美元占比较高有关。本文认为,在人民币汇率弹性显著增强的背景下,外贸企业要进一步树立汇率风险中性意识,加强汇率风险管理能力;金融机构要丰富外汇金融产品和服务,加强自身汇率风险敞口管理;政府部门要进一步丰富汇率避险服务,完善人民币跨境交易结算的基础设施,培育更多贸易双循环企业,提高对内外部经济形势变化的适应能力。

关键词：人民币汇率进出口贸易汇率弹性 J曲线效应

Discovery of a highly specific ^(18)F-labeled PET ligand for phosphodiesterase 10A enabled by novel spirocyclic iodonium ylide radiofluorination

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Acta Pharmaceutica Sinica B 2022年第4期12卷 1963-1975页

作者： Zhiwei Xiao Huiyi wei Yi Xu Ahmed Haider junjie wei Shiyu Yuan Jian Rong Chunyu Zhao Guocong Li weibin Zhang Huangcan Chen Yuefeng Li Lingling Zhang Jiyun Sun Shaojuan Zhang Hai-Bin Luo Sen Yan Qijun Cai Lu Hou Chao Che Steven H.Liang Lu Wang Center of Cyclotron and PET Radiopharmaceuticals Department of Nuclear Medicine and PET/CT-MRI Centerthe First Affiliated Hospital of Jinan UniversityGuangzhou 510630China Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital&Department of RadiologyHarvard Medical SchoolBostonMA 02114USA Department of Cardiology the First Affiliated Hospital of Jinan UniversityGuangzhou 510630China State Key Laboratory of Chemical Oncogenomics Key Laboratory of Chemical GenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Guangdong Landau Biotechnology Co.Ltd. Guangzhou 510555China Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikou 570228China Guangdong-Hongkong-Macao Institute of CNS Regeneration Ministry of Education CNS Regeneration Collaborative Joint LaboratoryJinan UniversityGuangzhou 510632China

As a member of cyclic nucleotide phosphodiesterase(PDE)enzyme family,PDE10A is in charge of the degradation of cyclic adenosine(cAMP)and guanosine monophosphates(cGMP).While PDE10A is primarily expressed in the medium spiny neurons of the striatum,it has been implicated in a variety of neurological disorders.Indeed,inhibition of PDE10A has proven to be of potential use for the treatment of central nervous system(CNS)pathologies caused by dysfunction of the basal ganglia–of which the striatum constitutes the largest component.A PDE10A-targeted positron emission tomography(PET)radioligand would enable a better assessment of the pathophysiologic role of PDE10A,as well as confirm the relationship between target occupancy and administrated dose of a given drug candidate,thus accelerating the development of effective PDE10A inhibitors.In this study,we designed and synthesized a novel ^(18)F-aryl PDE10A PET radioligand,codenamed[^(18)F]P10A-1910([^(18)F]9),in high radiochemical yield and molar activity via spirocyclic iodonium ylide-mediated radiofluorination.[^(18)F]9 possessed good in vitro binding affinity(IC_(50)=2.1 nmol/L)and selectivity towards PDE10A.Further,[^(18)F]9 exhibited reasonable lipophilicity(logD=3.50)and brain permeability(P_(app)>10×10^(−6) cm/s in MDCK-MDR1 cells).PET imaging studies of[^(18)F]9 revealed high striatal uptake and excellent in vivo specificity with reversible tracer kinetics.Preclinical studies in rodents revealed an improved plasma and brain stability of[^(18)F]9 when compared to the current reference standard for PDE10A-targeted PET,[^(18)F]MNI659.Further,dose–response experiments with a series of escalating doses of PDE10A inhibitor 1 in rhesus monkey brains confirmed the utility of[^(18)F]9 for evaluating target occupancy in vivo in higher species.In conclusion,our results indicated that[^(18)F]9 is a promising PDE10A PET radioligand for clinical translation.

关键词： Phosphodiesterase 10A PET radioligand 18F Spirocyclic iodonium ylide Nonhuman primate Target occupancy

Global stability of multi-group SEIRS epidemic models with vaccination

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International Journal of Biomathematics 2018年第1期11卷 143-174页

作者： Dejun Fan Pengmiao Hao Dongyan Sun junjie wei Department of MathematicsHarbin Institute of Technology (weihai) weihai Shandong 264209 P. R. China

In this paper, a susceptible–exposed–infective–recovered–susceptible (SEIRS) epidemic model with vaccination has been formulated. We studied the global stability of the corresponding single-group model, multi-group model with strongly connected network and multi-group model without strongly connected network by means of analyzing their basic reproduction numbers and the application of Lyapunov functionals. Finally, we provide some numerical simulations to illustrate our analysis results.

关键词：流行模型稳定性多组 Lyapunov 应用程序数字模拟流行病数字和

An Open-Source System for In Planta Gene Stacking by Bxbl and Cre Recombinases

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Molecular Plant 2014年第12期7卷 1756-1765页

作者： Lili Hou Yuan-Yeu Yau junjie wei Zhiguo Han Zhicheng Dong David W. Ow Plant Gene Engineering Center South China Agricultural Plant Molecular Analysis and Genetic Improvement Key Laboratory SouthChina Botanical Garden Chinese Academy of Sciences 723 Xingke Road Guangzhou 510650 China University of Chinese Academy of Sciences 19 Yuquan Road Beijing 100049 China Former Affiliation Plant Gene Expression Center USDA-ARS & Plant & Microbial Biology University of California-Berkeley 800Buchanan St. Albany CA 94710 USA

The rapid development of crops with multiple transgenic traits arouses the need for an efficient system for creating stacked cultivars. Most major crops rely on classical breeding to introgress the transgene from a laboratory variety to the numerous cultivars adapted to different growing regions. Even with vegetative propagated crops, genetic crosses are conducted during varietal improvement prior to vegetative cloning. The probability to assort the ＇x＇ number of transgenic loci into a single genome may seem trivial, （~）x for a diploid species, but given the ＇y＇ number of other nontransgenic traits that breeders also need to assemble into the same genome, the （~）~＊y probability for a ＇breeding stack＇ could quickly make the line conversion process unmanageable. Adding new transgenes onto existing transgenic varieties without creating a new segregating locus would require site-specific integration of new DNA at the existing transgenic locus. Here, we tested a recombinase-mediated gene-stacking scheme in tobacco. Sequential site-specific inte- gration was mediated by the mycobacteriophage Bxbl integrase-catalyzed recombination between attP and attB sites. Transgenic DNA no longer needed after integration was excised by Cre recombinase-mediated recombination of Iox sites. Site-specific integration occurred in -10% of the integration events, with half of those events usable as substrates for a next round of gene stacking. Among the site-specific integrants, however, a third experienced gene silencing. Overall, precise structure and reproducible expression of the sequentially added triple traits were obtained at an overall rate of -3% of the transformed clones--a workable frequency for the development of commercial cultivars. Moreover, since nei- ther the Bxbl-att nor the Cre-lox system is under patent, there is freedom to operate,

关键词： transgenesis site-specific recombination integrase gene targeting transgene expression.

基于InSAR技术的大跨桥梁温度变形监测研究

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湖南大学学报（自然科学版） 2024年第3期51卷 39-50页

作者：周云危俊杰李剑郝官旺郑佳缘朱正荣湖南大学土木工程学院湖南长沙410082 工程结构损伤诊断湖南省重点实验室(湖南大学) 湖南长沙410082 中建三局第一建设工程有限责任公司湖北武汉4300201

以国内某高速铁路钢拱桥为研究对象,选取2017—2018年期间59幅C波段Senti⁃nel-1号雷达卫星影像,利用PS-InSAR技术处理影像获得桥梁的视线向(Line of Sight,LOS)位移,根据SAR成像空间几何关系解算出支座的纵向位移.研究结果表明:支座纵... 详细信息

以国内某高速铁路钢拱桥为研究对象,选取2017—2018年期间59幅C波段Senti⁃nel-1号雷达卫星影像,利用PS-InSAR技术处理影像获得桥梁的视线向(Line of Sight,LOS)位移,根据SAR成像空间几何关系解算出支座的纵向位移.研究结果表明:支座纵向位移的时空特性与实际桥梁结构相符合,验证了PS-InSAR技术观测桥梁结构位移的可行性.建立支座纵向位移与温度的线性相关模型,并与结构健康监测系统的实测结果进行对比.两者吻合良好,相对误差控制在10%以内,验证了PS-InSAR测量桥梁结构位移的可靠性.利用有限元模拟温度作用下桥梁支座的位移变化,并与PS-InSAR位移时间序列进行对比.两者趋势基本一致,LOS向位移误差在[-10,10]mm,验证了PS-InSAR测量桥梁结构位移的准确性.

关键词：结构健康监测 PS-InSAR 大跨桥梁结构有限元方法温度变形监测

Photonic devices based on thin-film lithium niobate on insulator

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Journal of Semiconductors 2021年第4期42卷 43-52页

作者： Shuai Yuan Changran Hu An Pan Yuedi Ding Xuanhao Wang Zhicheng Qu junjie wei Yuheng Liu Cheng Zeng† Jinsong Xia Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

Lithium niobate on insulator(LNOI)is rising as one of the most promising platforms for integrated photonics due to the high-index-contrast and excellent material properties of lithium niobate,such as wideband transparency from visible to mid-infrared,large electro-optic,piezoelectric,and second-order harmonic coefficients.The fast-developing micro-and nanostructuring techniques on LNOI have enabled various structure,devices,systems,and applications.In this contribution,we review the latest developments in this platform,including ultra-high speed electro-optic modulators,optical frequency combs,opto-electro-mechanical system on chip,second-harmonic generation in periodically poled LN waveguides,and efficient edge coupling for LNOI.

关键词： thin-film lithium niobate modulator PPLN edge coupler

BIFURCATION ANALYSIS IN A GENERALIZED FRICTION MODEL WITH TIME-DELAYED FEEDBACK

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Annals of Differential Equations 2014年第2期30卷 199-215页

作者： Chuang Xu junjie wei Dept. of Math. Harbin Institute of Technology Harbin 150001 Dept. of Mathematical and Statistical Sciences University of AlbertaEdmonton Alberta Canada T6G 2G1

In this paper, we consider a generalized model of the two friction models, both of which have two different types of control forces with time-delayed feedback proposed by Ashesh Sara et al. By taking the time delay as the bifurcation parameter, we discuss the local stability of the Hopf bifurcations. Under some condition, the generalized model harbors a phenomenon that the equilibrium may undergo finite switches from stability to instability to stability and finally become unstable. By applying the method introduced by Faria and Magalhaes, we compute the normal form on the center manifold to determine the direction and stability of the Hopf bifurcations. Numerical simulations are carried out and more than one periodic solutions may exist according to the bifurcation diagram given by BIFTOOL. Finally a brief conclusion is presented.

关键词： Hopf bifurcation friction-driven oscillation time-delayed feedback periodic solution complex dynamical behavior