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瑞香狼毒贝壳杉烷型二萜类合成酶功能表征

中国中药杂志 2024年第9期49卷 2410-2421页

作者：谭洪虎夏梦苏平黄璐琦南京中医药大学药学院江苏南京210023 中国中医科学院中药资源中心道地药材品质保障与资源持续利用全国重点实验室北京100700

ent-柯巴基焦磷酸合酶(ent-copalyl diphosphate synthase,CPS)与ent-贝壳杉烯合酶(ent-kaurene synthase,KS)的连续催化是植物以香叶基香叶基焦磷酸(geranylgeranyl pyrophosphate,GGPP)为底物开启赤霉素生物合成路径的关键步骤。该研究通过分析与挖掘瑞香狼毒的转录组数据,成功克隆得到赤霉素途径的2个关键二萜合酶基因SchCPS和SchKS。二者完整开放阅读框分别为2595、1701 bp,编码864、566个氨基酸残基,生物信息学分析预测其相对分子质量分别为97.9、64.6 kDa,理论等电点为5.61、6.12,均为亲水性蛋白。序列比对及系统发育树显示,SchCPS蛋白含有CPS基因家族保守的LHS、PNV及DxDD基序,归类于TPS-c亚家族;SchKS蛋白含有KS基因家族保守的DDxxD、NSE/DTE和PIx基序,归类于TPS-e亚家族。功能验证结果表明,SchCPS可催化GGPP质子化并环化成ent-CPP,SchKS则作用于ent-CPP去磷酸化并再次环化生成贝壳杉烯。该文首次从瑞香狼毒中克隆获得SchCPS与SchKS全长基因,并完成功能验证,不仅丰富了现有的CPS和KS基因库,也为瑞香狼毒中更多活性成分基因的克隆与生物合成途径解析奠定了基础。

关键词：瑞香狼毒贝壳衫烷二萜合酶功能鉴定生物信息学

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Antibacterial,antioxidant and antiproliferation activities of essential oils and ethanolic extracts from Chinese mugwort(Artemisia vulgaris L.)leaf in Shanxi

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Traditional Medicine Research 2024年第1期9卷 47-56页

作者： hu-tan-Xian Zhang Feng-Ru Lyu Jia-Tong He Chen-Yu Liu Zheng-Yang Zhou Rui-Jie Wu Zi-Qing Zhao He Li School of Chemistry and Chemical Engineering North University of ChinaTaiyuan 030051China Shanxi Jinshuo Biomedical Technology Co. Ltd.Jinzhong 030600China

Background:Artemisia vulgaris,a medicinal aromatic plant,is widely used as a food item,tonic pharmaceutical,and cosmetic industry additive owing to its antibacterial,antihypertensive,hepatoprotective,antioxidant,and antispasmodic *** the effect of different geographic locations on the chemical composition and bioactivities of its extracts is ***:Biological activities of essential oils and ethanol extracts of three varieties of Artemisia vulgaris leaves,which are grown in Shanxi province China,were ***:Gas chromatography-mass spectrometry analysis revealed that the main components of essential oils were terpenes and *** oils and ethanol extract of Artemisia vulgaris leaves possessed good antioxidant activities,and their half maximal inhibitory concentrations determined using 1,1-diphenyl-2-picrylhydrazyl and 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate)assays were 57.0 and 22.9μg/mL,*** essential oils also exhibited remarkable antibacterial activity against three foodborne pathogenic bacterial *** ethanol extract presented a high anticancer activity against the MGC-803 human gastric cancer cell ***:These biological activities were well correlated with the composition of the extract and EOs,which in turn is affected by the genetic composition of Artemisia vulgaris and geographic location and diverse climatic condition under which it is *** findings demonstrate the remarkable potential of Artemisia vulgaris as a valuable source of antioxidant,antibacterial,and anticancer agents.

关键词： Artemisia vulgaris essential oils ethanol extracts antioxidant antiproliferation

基于扩频通信技术的农村电力负荷自动监测方法

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自动化技术与应用 2024年第7期43卷 102-106页

作者：宿连超王涛谭虎国网山东省电力公司潍坊供电公司山东潍坊261041

以掌握农村电力运行情况为目的,提出基于扩频通信技术的农村电力负荷自动监测方法。首先获取农村电力运行数据,利用无线扩频通信技术将数据进行扩频;然后将农村电力负荷数据作为输入,使用累积和滑动窗算法提取农村电力负荷投切时特征,... 详细信息

以掌握农村电力运行情况为目的,提出基于扩频通信技术的农村电力负荷自动监测方法。首先获取农村电力运行数据,利用无线扩频通信技术将数据进行扩频;然后将农村电力负荷数据作为输入,使用累积和滑动窗算法提取农村电力负荷投切时特征,采用二维离散模糊算法建立电力负荷自动监测模型。实验结果表明:该方法具备良好的无线扩频通信性能,可以高精度提取电力负荷特征,准确监测农村电力负荷投切跳变和突变点,具有一定的实际应用价值。

关键词：扩频通信技术农村电力负荷自动监测设备投切滑动窗

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风光沼储交直流混合农村微电网经济技术优化

中国电力 2024年第3期57卷 27-33页

作者：谭虎王小亮徐亭亭赵珂宿连超张文玉辛征国网山东省电力公司潍坊供电公司山东潍坊261021 山东建筑大学信息与电气工程学院山东济南250101

搭建了风光沼储交直流混合微电网系统模型,在满足系统供电可靠性的条件下,以新能源利用率最高、经济成本最优、碳排放最小进行多目标优化,研究了在某气候条件下,该微电网能源系统的经济技术最优配置。

关键词：电力市场多能互补系统农村微电网

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Multi-Axis Attention With Convolution Parallel Block for Organoid Segmentation

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1295-1297页

作者： Pengwei hu Xun Deng Feng tan Lun hu Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of SciencesUrumqi 830011 University of Chinese Academy of Sciences Beijing 100049 Xinjiang Laboratory of Minority Speech and Language Information Processing Urumqi 830011China Merck KGaA Darmstadt 64293Germany

Dear Editor,This letter presents an organoid segmentation model based on multi-axis attention with convolution parallel *** adeptly captures dynamic dependencies within bright-field microscopy images,improving global ... 详细信息

关键词： letter convolution organo

Strong invariance principle for a counterbalanced random walk

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 370-380页

作者： tan hui-qun hu Zhi-shui DONG Liang International Institute of Finance School of ManagementUniversity of Science and Technology of ChinaHefei 230026China Center for Basic Teaching and Experiment Nanjing University of Science and TechnologyJiangyin 214443China

We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as *** n≥2,X_(n) is a new independent sample from some fixed law̸=0 with a fixed probability p,andX_(n)=−X_(v(n))with probability 1−p,where v(n)is a uniform random variable on{1;…;n−1}.We apply martingale method to obtain a strong invariance principle forS_(n).

关键词： random walk martingale invariance principle

Effect of catalyst diesel particulate filter aging and catalyst loadings on particulate emission characteristics from a diesel vehicle

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Journal of Environmental Sciences 2024年第2期136卷 35-44页

作者： Yunhua Zhang Diming Lou Piqiang tan Zhiyuan hu Liang Fang School of Automotive Studies Tongji UniversityShanghai 201804China

In this study,the effect of new and used catalyzed diesel particulate filter(CDPF)with different catalyst loadings on the particulate emissions including the particle mass(PM),particle number(PN),particle size distribution(PSD)and geometric mean diameter(GMD)from a diesel vehicle were investigated based on a heavy chassis *** showed that more than 97.9%of the PN and 95.4%of the PM were reduced by the CDPF,and the reduction efficiency was enhanced by the catalyst *** using the CDPF,the PSD transformed from bimodal to trimodal with the peak shifting towards smaller particle size,more nucleation mode particles were reduced compared with accumulation mode ones,but the reduction effect on the accumulation mode particles was more significantly influenced by the catalyst ***,the CDPF increased the accumulation mode particles proportion,producing a larger *** the used CDPF,its reduction effect on the particulate emissions enhanced,especially for the PM in accumulation *** PSD returned to bimodal,but the peak at accumulation mode began to be higher than that at nucleation mode,illustrating that more nucleation mode particles was *** aging of the CDPF resulted in greater effect on the PN-based PSD than that of PM-based PSD,but the effect of catalyst loading on the PN and PM emission factors was *** used CDPF further increased the GMD,and the effect of catalyst loading on the GMD was strengthened,a higher catalyst loading led to a reduction in the GMD.

关键词： Catalyzed diesel particulate filter (CDPF) Catalyst loading Aging Particle Particle size distribution Geometric mean diameter

Type Synthesis of Self-Alignment Parallel Ankle Rehabilitation Robot with Suitable Passive Degrees of Freedom

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 160-175页

作者： Ya Liu Wenjuan Lu Dabao Fan Weijian tan Bo hu Daxing Zeng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China Dongguan Engineering Technology Research Center for Parallel Robot Dongguan 523808China The DGUT Innovation Center of Robotics and Intelligent Equipment Dongguan 523808China

The current parallel ankle rehabilitation robot(ARR)suffers from the problem of difficult real-time alignment of the human-robot joint center of rotation,which may lead to secondary injuries to the *** study investigates type synthesis of a parallel self-alignment ankle rehabilitation robot(PSAARR)based on the kinematic characteristics of ankle joint rotation center drift from the perspective of introducing"suitable passive degrees of freedom(DOF)"with a suitable number and ***,the self-alignment principle of parallel ARR was proposed by deriving conditions for transforming a human-robot closed chain(HRCC)formed by an ARR and human body into a kinematic suitable constrained system and introducing conditions of"decoupled"and"less limb".Second,the relationship between the self-alignment principle and actuation wrenches(twists)of PSAARR was analyzed with the velocity Jacobian matrix as a"bridge".Subsequently,the type synthesis conditions of PSAARR were ***,a PSAARR synthesis method was proposed based on the screw theory and type of PSAARR synthesis ***,an HRCC kinematic model was established to verify the self-alignment capability of the *** this study,93 types of PSAARR limb structures were synthesized and the self-alignment capability of a human-robot joint axis was verified through kinematic analysis,which provides a theoretical basis for the design of such an ARR.

关键词： Ankle rehabilitation robot Self-alignment Parallel mechanism Type synthesis Screw theory

Fixed-Time Antidisturbance Consensus Tracking for Nonlinear Multiagent Systems With Matching and Mismatching Disturbances

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1410-1423页

作者： Xiangmin tan Chunyan hu Guanzhen Cao Qinglai Wei Wei Li Bo Han Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190 School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100049China Institute of Automation Chinese Academy of SciencesBeijing 100190 School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China IEEE

In this paper,fixed-time consensus tracking for mul-tiagent systems(MASs)with dynamics in the form of strict feed-back affine nonlinearity is addressed.A fixed-time antidistur-bance consensus tracking protocol is proposed,which consists of a distributed fixed-time observer,a fixed-time disturbance observer,a nonsmooth antidisturbance backstepping controller,and the fixed-time stability analysis is conducted by using the Lyapunov theory *** paper includes three main ***,a distributed fixed-time observer is developed for each follower to obtain an estimate of the leader’s output by utilizing the topology of the communication ***,a fixed-time disturbance observer is given to estimate the lumped disturbances for feedforward ***,a nonsmooth antidisturbance backstepping tracking controller with feedforward compensation for lumped disturbances is *** order to mitigate the“explosion of complexity”in the tradi-tional backstepping approach,we have implemented a modified nonsmooth command filter to enhance the performance of the closed-loop *** simulation results show that the pro-posed method is effective.

关键词： Antidisturbance backstepping consensus tracking fixed-time stability multiagent system(MASs) strict feedback affine nonlinear systems.