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Frontiers of Chemical Science and Engineering 2023年第12期17卷 2101-2113页

作者： Yihong Yang Siyue Ma Ting Li Jingjing He Shitao liu Hongwu liu Jiaojiao Zhang Xiang Zhou liwei liu Song Yang National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural Bioengineering(Ministry of Education)Center for R&D of Fine Chemicals of Guizhou UniversityGuiyang 550025China

In response to the reduction of food production and economic losses caused by plant bacterial diseases, it is necessary to develop new, efficient, and green pesticides. Natural products are rich and sustainable source for the development of new pesticides due to their low toxicity, easy degradation, and eco-friendliness. In this study, we prepared three series of ursolic acid derivatives and assessed their antibacterial ability. Most target compounds exhibited outstanding antibacterial activities. Among them, the relative optimal EC50 values of Xanthomonas oryzae pv. oryzae and Xanthomonas axonopodis pv. citri were 2.23 (A17) and 1.39 (A16) μg·mL^(-1), respectively. The antimicrobial mechanism showed that compound A17 induced an excessive accumulation and production of reactive oxygen species in bacteria and damaged the cell membrane integrity to kill bacteria. More interestingly, the addition of low concentrations of exogenous hydrogen peroxide enhanced the antibacterial efficacy of compound A17 against Xanthomonas oryzae pv. oryzae. These entertaining results suggested that compound A17 induced an apparent apoptotic behavior in the tested bacteria. Overall, we developed the promising antimicrobial agents that destroyed the redox system of phytopathogenic bacteria, further demonstrating the unprecedented potential of ursolic acid for agricultural applications.

关键词： ursolic acid antibacterial activities reactive oxygen species apoptosis

Strategic Behavior and Optimization in an Unobservable Constant Retrial Queue with Balking and Set-Up Time

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Journal of Systems Science and Information 2020年第3期11卷 273-290页

作者： Linlin WANG liwei liu Zhen WANG Xudong CHAI School of Science Nanjing University of Science and TechnologyNanjing 210094China

An M/M/1 constant retrial queue with balking customers and set-up time is *** the system becomes empty, the server will be turned down to reduce operating costs, and it will be activated only when there is a customers arrives. In this paper, the almost unobservable case is studied, in which the information of the queue length is unavailable, whereas the state of the server can be obtained. Firstly, the steady state solutions are derived and the individual equilibrium strategies are analyzed. In addition, social optimization problems, including cost analysis and social welfare maximization are investigated by using the PSO algorithm. Finally, by appropriate numerical examples, the sensitivity of some main system parameters is shown.

关键词： observable system queue

Aggregation-induced emission luminogen-assisted stimulated emission depletion nanoscopy for super-resolution mitochondrial visualization in live cells

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Nano Research 2018年第11期11卷 6023-6033页

作者： Dongyu Li Xiang Ni Xiaoyan Zhang liwei liu Junle Qu Dan Ding Jun Qian State Key Laboratory of Modern Optical Instrumentation Centre for Optical and Electromagnetic Research Zhejiang Provincial Key Laboratory for Sensing Technologies Zhejiang University Hangzhou 310058 China State Key Laboratory of Medicinal Chemical Biology Key Laboratory of Bioactive Materials Ministry of Education and College of Life Sciences Nankai University Tianjin 300071 China Key Laboratory of Optoelectrical Devices and Systems Ministry of Education Shenzhen University Shenzhen 518060 China Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy Cancer Institute Xuzhou Medical University Xuzhou 221004 China

Aggregation-induced emission luminogens (AIEgens) are fluorescent agents that are ideal for bioimaging and have been widely used for organelle targeting, cellular mapping, and tracing. Owing to their promising characteristics, AIEgen-based nanoparticles have recently been used for the stimulated emission depletion (STED) super-resolution imaging of fixed cells. In the present study, and for the first time, we used an AIEgen for dynamic STED nanoscopic imaging of a specific organelle in live cancer cells. TPA-T-CyP is a synthetic red&NIR-emitting luminogen with AIE features that can spontaneously and specifically aggregate on mitochondria without the need for encapsulation or surface modification. The STED efficiency of aggregated TPA-T-CyP can reach more than 80%, and super-resolution imaging of TPA-T-CyP-stained mitochondria in live HeLa cells is possible, with a lateral spatial resolution of 74 nm. We found that TPA-T-CyP enabled the dynamic visualization of mitochondria, and the motion, fusion, and fission of mitochondria were clearly observable on a super-resolution scale. AIEgen-based super-resolution organelle visualization has great potential for many basic biomedical studies.

关键词： aggregation-induced emission stimulated emission depletion nanoscopy mitochondria dynamic visualization

Influence of morphine on levels of type Ⅱ inhibitory guanine nucleotide binding protein in primary hippocampal neurons

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Neural Regeneration Research 2008年第5期3卷 465-468页

作者： Qinghua Wu Qiang Fu Xinhua Wang Jianhua Zhao liwei liu Shirong Tang Department of Anesthesiology the 150 Hospital of Chinese PLA Luoyang 471031 Henan Province China Department of Anesthesiology General Hospital of Chinese PLA Beijing 100853 China Department of Anesthesiology Orient Hospital Affiliated to Shanghai Tongji University Shanghai 200120 China Department of Anesthesiology General Hospital of Jinan Military Area Command of Chinese PLA Jinan 250031 Shandong Province China

BACKGROUND： The pharmacological action of opioid drugs is related to signal transduction of inhibitory guanine nucleotide binding protein. OBJECTIVE： To quantitatively and qualitatively analyze the influence of morphine on levels of type Ⅱ inhibitory guanine nucleotide binding protein （Gi2 protein） in primary cultured hippocampal neurons at different time points. DESIGN, TIME AND SETTING： A randomized controlled study, which was performed at the Department of Neurobiology, Changzheng Hospital, Second Military Medical University of Chinese PLA between September 2002 and March 2004. MATERIALS： Cerebral hippocampal neurons were obtained from newborn SD rats at 1 2 days of age. Biotin-antibody Ⅱ-avidin fluorescein isothiocyanate （Avidin-FITC） was purchased from Sigma Company （USA） and the Gi2 protein polyclonal antibody from Santa Cruz Biochemistry Company （USA）. METHODS： Seven days after culture, mature hippocampal neurons were randomly divided into six groups： 4-, 8-, 16-, 24-, and 48-hour morphine groups, and a blank control group. Neurons in the morphine groups received morphine （10 μ mol/L）, which could cause alterations of G-protein mRNA and cAMP expression in the prefrontal cortex. Neurons in the blank control group were given the same volume of saline. MAIN OUTCOME MEASURES： Gi2 protein levels were detected by an immunofluorescence technique, and were analyzed by the image analytic system with the use of green fluorescence intensity. RESULTS： Gi2 protein levels in hippocampal neurons gradually decreased in the 4-, 8-, 16-, 24-, and 48-hour morphine groups. In particular, Gi2 protein levels in the 16-, 24-, and 48-hour morphine groups were significantly lower than that in the blank control group （P 〈 0.05 0.01）. CONCLUSION： Morphine may decrease Gi2 protein level in primary hippocampal neurons, and the decreasing trend is positively related to morphine-induced time.

关键词： morphine hippocampal neurons immunofluorescence type Ⅱ inhibitory guanine nucleotide binding protein

Brain regional changes of guanine nucleotide binding protein-inhabitant 2 in acute and chronic morphine-tolerant and-dependent rats

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Neural Regeneration Research 2008年第7期3卷 751-755页

作者： Qinghua Wu Qiang Fu Xinhua Wang Jianhua Zhao liwei liu Shirong Tang Department of Anesthesiology the 150 Hospital of Chinese PLA Luoyang 471031 Henan Province China Department of Anesthesiology General Hospital of Chinese PLA Beijing 100853 China Department of Anesthesiology Dongfang Hospital Tongji University Shanghai 200120 China Department of Anesthesiology General Hospital of Jinan Mifitary Area Command of Chinese PLA Jinan 250031 Shandong Province China

BACKGROUND： Drug addiction involves two main central nervous systems, namely the dopamine and noradrenaline systems. These systems are primarily distributed in five brain regions： the ventral tegmental area, the nucleus accumbens, the prefrontal cortex, the hippocampus, and the locus coeruleus. OBJECTIVE： To investigate regional changes of guanine nucleotide binding protein-inhabitant 2 （Gi2） in dopaminergic and noradrenergic neurons in brains of morphine-tolerant and -dependent rats. DESIGN, TIME, AND SETTING： A randomized control study was performed at the Department of Neurobiology in the Second Military Medical University of Chinese PLA （Shanghai, China） between September 2002 and March 2004. MATERIALS： Thirty-six, healthy, male, Sprague-Dawley （SD） rats were used to establish morphine-dependent models. Morphine hydrochloride was a product of Shenyang First Pharmaceutical Factory （China）; naloxone hydrochloride was a product of Beijing Four-Ring Pharmaceutical Factory （China）; and α subunit of Gi2 antibody was offered by Santa Cruz Biotechnology, lnc （USA）. METHODS： Thirty-six SD rats were randomly divided into six groups （n = 6）：（1） acute morphine-dependent group, （2） acute abstinent group, （3） acute control group, （4） chronic morphine-dependent group, （5） chronic abstinent group, and （6） chronic control group. Rats in the acute morphine-dependent and the acute groups were injected with morphine （5 mg/kg）, one injection every two hours, for a total of eight injections. In the acute and chronic morphine-dependent rat models, morphine withdrawal syndrome was precipitated by an injection of naloxone （5 mg/kg）. Rats in the acute control group were given a peritoneal injection of physiological saline at the same administration time as the above two groups. Rats in the chronic morphine-dependent and chronic abstinent groups were injected with morphine three times per day. The administration dose on day 1 was initially 5 mg/kg at 20：00, which increased by 5 m

关键词： morphine dependence/tolerance guanine nucleotide binding protein-inhabitant 2 hippocampus ventral tegmental area mucleus accumbens prefrontal cortex locus coeruleus

Electrical and Raman properties of p-type and n-type modified graphene by inorganic quantum dot and organic molecule modification

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Science China(Physics,Mechanics & Astronomy) 2011年第3期54卷 416-419页

作者： HOU YanXue GENG XiuMei LI YuanZuo DONG Bin liu liwei SUN MengTao College of Science Yanshan University Qinhuangdao 066004 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215125 China School of Science Dalian Nationalities University Dalian 116600 China

We obtained n-type and p-type modified graphene by mixing quantum dots and depositing electron-acceptor molecules on the surface of graphene, respectively. The electrical and optical properties of these two types of samples were measured. For n-type modified graphene, the electrons were transferred from quantum dots to graphene. The resistance of these quantum dots in modified n-type graphene is significantly smaller than that of pristine graphene. For p-type graphene, modified by electron-acceptor organic molecules of tetracyanoethylene (TCNE), electrons were transferred from graphene to TCNE molecules. The resistance of this molecular modified p-type graphene is about 10% larger than that of pristine graphene. The charge transfer effect on the optical properties of graphene was investigated with Raman spectra.

关键词： p-type and n-type graphene electrical property Raman property

Intriguing one-dimensional electronic behavior in emerging two-dimensional materials

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Nano Research 2021年第11期14卷 3810-3819页

作者： Xuan Song Teng Zhang Huixia Yang Hongyan Ji Jiatao Sun liwei liu Yeliang Wang Hongjun Gao School of Information and Electronics MIIT Key Laboratory for Low-Dimensional Quantum Structure and DevicesBeijing Institute of TechnologyBeijing100081China Institute of Physics Chinese Academy of SciencesBeijing100190China

Tomonaga-Luttinger liquid(TLL),a peculiar one-dimensional(1D)electronic behavior due to strong correlation,was first studied in 1D nanostructures and has attracted significant attention over the last several *** the rise of new two-dimensional(2D)quantum materials,1D nanostructures in 2D materials have provided a new platform with a well-defined configuration at the atomic scale for studying TLL electronic *** this paper,we review the recent progress of TLL electronic features in emerging 2D materials embedded with various 1D nanostructures,including island edges,domain walls,and 1D moiré***,novel physical phenomena,such as 1D edge states in 2D transition metal dichalcogenides(TMDs),helical TLL in 2D topological insulators(2DTI),and chiral TLL in 2D quantum Hall systems,are described and discussed at the *** also analyze challenges and opportunities at the frontier of this research area.

关键词： One-dimensional electronic system Tomonaga-Luttinger liquid two-dimensional materials edge states domain wall

Advance in two-dimensional twisted moirématerials:Fabrication,properties,and applications

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Nano Research 2023年第2期16卷 2579-2596页

作者： Han Yang liwei liu Huixia Yang Yu Zhang Xu Wu Yuan Huang Hong-Jun Gao Yeliang Wang MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices School of Integrated Circuits and ElectronicsBeijing Institute of TechnologyBeijing 100081China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Two-dimensional(2D)twisted moirématerials,a new class of van der Waals(vdW)layered heterostructures with different twist angles between neighboring layers,have attracted tremendous attention due to their rich emerging *** this review,we systematically summarize the recent progress of 2D twisted moiré***,we introduce several representative fabrication methods and the fascinating topographies of the twisted moiré***,we discuss various remarkable physical properties related to twisted angles,including flat bands,unconventional superconductivity,ferromagnetism,and *** also analyze the potential applications in various twisted moiré***,the challenges and future perspectives of the twisted moirématerials are *** work would spur edge-cutting ideas and related achievements in the scientific and technological frontiers of 2D twisted moirématerials.

关键词： two-dimensional(2D)materials moiré twist superconductivity ferromagnetism

Monitoring microenvironment of Hep G2 cell apoptosis using two-photon fluorescence lifetime imaging microscopy

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Journal of Innovative Optical Health Sciences 2022年第3期15卷 36-44页

作者： Kexin Wang Shiyao Tang Shiqi Wang Fangrui Lin Gengjin Zou Junle Qu liwei liu Key Laboratory of Optoelectronic Devices and Systems of Guangdong Province&Ministry of Education College of Physics and Optoelectronic Engineering Shenzhen University ShenzhenGuangdong ProvinceP.R.China

Apoptosis is very important for the maintenance of cellular homeostasis and is closely related to the occurrence and treatment of many *** in cells play a crucial role in programmed cell death and redox *** adenine dinucleotide(NAD(P)H)is the primary producer of energy in mitochondria,changing NAD(P)H can directly reflect the physiological state of ***,NAD(P)H can be used to evaluate metabolic *** this paper,we propose a noninvasive detection method that uses two-photon fluorescence lifetime imaging microscopy(TP-FLIM)to characterize apoptosis by observing the binding kinetics of cellular endogenous NAD(P)*** result shows that the average fluorescence lifetime of NAD(P)H and the fluorescence lifetime of protein-bound NAD(P)H will be affected by the changing pH,serum content,and oxygen concentration in the cell culture environment,and by the treatment with reagents such as H2O2 and ***(PTX).This noninvasive detection method realized the dynamic detection of cellular endogenous substances and the assessment of apoptosis.

关键词： Apoptosis nicotinamide adenine dinucleotide two-photon fluorescence lifetime imaging microscopy imaging microenvironment Hep G2

Implementation and application of FRET-FLIM technology

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Journal of Innovative Optical Health Sciences 2019年第5期12卷 57-68页

作者： Shiqi Wang Binglin Shen Sheng Ren Yihua Zhao Silu Zhang Junle Qu liwei liu Key Laboratory of Optoelectronic Devices and Systems of Guangdong Province College of Physics and Optoelectronic Engineering Shenzhen University Shenzhen518060P.R.China

With the development of the new detection methods and the function of fluorescent molecule,researchers hope to further explore the internal mechanisms of organisms,monitor changes in the intracellular microenvironment,and dynamic processes of molecular interactions in ***-rescence resonance energy transfer(FRET)describes the energy transfer process between donor fluorescent molecules and acceptor fluorescent *** is an important means to detect protein-protein interactions and protein conformation changes in *** lifetime imaging microscopy(FLIM)enables noninvasive measurement of the fAuorescence lifetime of fluorescent particles in *** FRET-FLIM technology,which is use FLIM to quantify and analyze FRET,enables real-time monitoring of dynamic changes of proteins in biological cells and analysis of protein interaction *** distance between donor and acceptor and their respective fAuorescent lifetime,which are of great importance for studying the mechanism of intracellular activity can be obtained by data analysis and algorithm ftting.

关键词： Fluorescence resonance energy transfer fuorescenc-lifetime imaging microscopy protein-protein interaction