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Two New Antibacterial Flavanones from Sophora flavescens

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Chinese Chemical Letters 2006年第8期17卷 1048-1050页

作者： Mei Ai CAO Xiao Bai SUN Pei hua zhao Cheng shan YUAN State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

Two new lavandulylated flavanones,（2R, 3R）-8-1avandulyl-2＇-methoxy-5, 7, 4＇-trihydroxyflavanonol （1） and 8-1avandulyl-5,7, 4＇-trihydroxyflavonol （2）,were isolated from the dry roots of S *** structures were e... 详细信息

关键词： Sophora flavescens Fabaceae flavanone antibacterial activity.

Protease inhibitors in Bombyx mori silk might participate in protecting the pupating larva from microbial infection

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Insect Science 2016年第6期23卷 835-842页

作者： You-shan Li hua-Wei Liu Rui Zhu Qing-You Xia Ping zhao State Key Laboratory of Silkworm Genome Biology Southwest University Chongqing Vitamin D Research Institute Shaanxi University of Technology Hanzhong Shaanxi Province School of Management Shaanxi University of Technology Hanzhong Shaanxi Province China

Pupae inside cocoons rarely suffer from disease. It is apparent that some factors in the cocoon exert antimicrobial effects whereby the pupae inside can be protected from microbial infection. In the present study, we investigated the expression of cocoon protease inhibitors using immunoblotting and activity staining. Enzymatic hydrolysis of cocoon proteins in vitro was performed to characterize their roles in protecting the cocoon from microbial proteases. We found that some protease inhibitors, particularly trypsin inhibitor-like （TIL）-type protease inhibitors, can be secreted into the cocoon layer during the spinning process, thereby providing effective protection to the cocoon and pupa by inhibiting the extracellular proteases that can be secreted by pathogens.

关键词： Bombyx mori cocoon enzymatic hydrolysis microbial proteases protease inhibitors pupating larva

A generalized trajectory tracking controller for robot manipulators with bounded inputs

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1500-1508页

作者： hua-shan LIU Shi-qiang ZHU State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

A generalized controller based on stability theory of singularly perturbed systems is proposed,to deal with the problem of bounded actuator inputs in robot trajectory tracking *** saturation function with error-gain matrix is applied in the torque control law,which ensures the upper bound of torque inputs in any given limited *** appropriately setting the entries of the error-gain matrix,the tracking performance can be ***,a pseudo signal is generated from a linear filter to substitute for the actual velocity error,eliminating the need for velocity ***,to verify the ef-fectiveness of the generalized controller,a new saturated controller with error-gain-contained arc tangent function is *** experiments show that the proposed controller can strictly guarantee the bound of the torque inputs in situations with non-zero initial tracking errors,and gives a better tracking result than other controllers.

关键词： Robot Tracking control Singular perturbation Bounded input

The RNA-binding domain of DCL3 is required for long-distance RNAi signaling

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aBIOTECH 2024年第1期5卷 17-28页

作者： Jie Li Bo-Sen Zhang hua-Wei Wu Cheng-Lan Liu Hui-shan Guo Jian-hua zhao State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic Interactions University of the Chinese Academy of SciencesBeijing 100049China Qilu Zhongke Academy of Modern Microbiology Technology Jinan 250022China

Small RNA(sRNA)-mediated RNA silencing(also known as RNA interference,or RNAi)is a conserved mechanism in eukaryotes that includes RNA degradation,DNA methylation,heterochromatin formation and protein translation *** plants,sRNAs can move either cell-to-cell or systemically,thereby acting as mobile silencing signals to trigger noncell autonomous ***,whether and what proteins are also involved in noncell autonomous silencing have not been *** this study,we utilized a previously reported inducible RNAi plant,PDSi,which can induce systemic silencing of the endogenous PDS gene,and we demonstrated that DCL3 is involved in systemic PDS silencing through its RNA binding *** confirmed that the C-terminus of DCL3,including the predicted RNA-binding domain,is capable of binding short *** affecting RNA binding,but not processing activity,reduced systemic PDS silencing,indicating that DCL3 binding to RNAs is required for the induction of systemic *** mosaic virus infection assays showed that the RNA-binding activity of DCL3 is required for antiviral RNAi in systemically noninoculated *** findings demonstrate that DCL3 acts as a signaling agent involved in noncell autonomous silencing and an antiviral effect in addition to its previously known function in the generation of 24-nucleotide sRNAs.

关键词： RNAi signaling DCL3 RBD RNAs Cucumber mosaic virus

Determination of Scaling Parameter and Dynamical Resonances in Complex-Rotated Hamiltonian Ⅰ:Theory

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Communications in Theoretical Physics 2008年第3期49卷 599-606页

作者： zhao Fang zhao Mei-shan Department of Mathematics and Department of Chemistry The University of Chicago Chicago Illinois 60637 USA The James Pranck Institute and Department of Chemistry The University of Chicago Chicago Illinois 60637 USA

In this paper we present a theoretical analysis on the determination of the scaling parameter in the complex-rotated Hamiltonian, which has served as a basis for successful applications of the rigged Hilbert space theory for resonances. Based on the complex energy eigenvalue, E（θ） = ER（θ） - iГ（θ）/2, as a function of the scaling parameter θ, we find that for potential barrier scattering, the condition dГ（θI）/dθ = 0 uniquely determines the scaling parameter 8. The condition d ER （θR）/ dθ = 0 is merely a consequence of the Virial theorem and θI =θR is not a necessary condition for a resonance state. We also provide a harmonic approximation formMism for resonances in scattering over a potential barrier.

关键词： complex-rotated Hamiltonian potential scattering resonances rigged Hilbert space

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Regioselective C-C bond cleavage/aminocarbonylation cascade under copper catalysis

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Science China Chemistry 2024年第11期67卷 3798-3806页

作者： Qi-Chao shan Yan zhao Yong Wu Hong-Fei Liu Xin-hua Duan Li-Na Guo Department of Chemistry School of ChemistryEnergy Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China

A regioselective C-C bond cleavage/aminocarbonylation cascade is presented. In recent years, tremendous progress has been made in the alkoxyl radical-mediated C-C bond cleavage of unstrained monocarbocycles. In contrast, the deconstruction and functionalization of bicyclic skeletons has been less developed and has mainly focused on the ring expansion process. Inspired by the aromatization-driven C-C bond cleavage, here we demonstrate a ring-opening/aminocarbonylation cascade under copper catalysis, in which the formation of a stable γ-lactam or succinimide skeleton reverses the selectivity of C-C cleavage. Remarkably, the photo and thermal assistance is not required when the succinimide skeleton is formed during the ring opening process. DFT calculations revealed that this unexpected ring-opening process is thermodynamically and kinetically favourable.

关键词： C-C bond cleavage controllable regioselectivity aminocarbonylation bicyclic alkoxy radical

A novel linear microprobe array for the fabrication of neural microelectrodes

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Science China(Technological Sciences) 2015年第2期58卷 346-351页

作者： zhao shan shan PEI Wei hua zhao Hui WANG Yi Jun CHEN San Yuan CHEN Yuan Fang ZHANG He GUO Dong Mei GUI Qiang CHEN Hong Da State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Institute for Neural Computation University of California San Diego

A novel linear microprobe array(LMPA)has been developed by a conventional microfabrication method from *** LMPA leverages the properties of conventional microwire with additional features of naturally formed regular *** the help of periodic microprobe arrays and double-side V-grooves fabricated in advance between each pair of the two microprobes’rear ends,the number of microprobe units for assembly in one array can be flexibly chosen by cleavage fracture from the *** fabrication method was demonstrated and the prototype device was assessed by electrochemical impedance spectroscopy(EIS)and in vivo *** SNR of the spikes recorded was 6.

关键词： LMPA regular spacing cleavage fracture V-groove

Growth factors induce the improved cardiac remodeling in autologous mesenchymal stem cell-implanted failing rat hearts

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第4期11卷 238-248页

作者： Ze-wei TAO Long-gui LI zhao-hua GENG Tao DANG shan-jun ZHU Department of Cardiovascular Diseases Xinqiao Hospital Third Military Medical University Chongqing 40003 7 China

Therapeutically delivered mesenchymal stem cells (MSCs) improve ventricular remodeling. However,the mechanism underlying MSC cardiac remodeling has not been clearly determined. Congestive heart failure (CHF) was induced in rats by cauterization of the left ventricular free wall. MSCs were cultured from autologous bone marrow and injected into the border zone and the remote myocardium 5 d after injury. Ten weeks later,when compared with sham operation,CHF significantly increased nucleus mitotic index,capillary density,and expression of insulin-like growth factor 1,hepatocyte growth factor and vascular endothelial growth factor in the border zone (P<0.01) and decreased each of them in the remote myocardium (P<0.05 or P<0.01). MSC implantation in CHF dramatically elevated ex-pression of these growth factors in the remote myocardium and further elevated their expression in the border zone when compared with CHF without MSC addition (P<0.05 or P<0.01). This was paralleled by a higher nucleus mitotic index and a significantly increased capillary density both in the remote myocardium and in the border zone,and by a lower percentage of area of collagen and a higher percentage of area of myocardium in the border zone (P<0.05 or P<0.01),and cardiac remodeling markedly improved. Autologous MSC implantation promoted expression of growth factors in rat failing myocardium,which might enhance cardiomyogenesis and angiogenesis,and improved cardiac remodeling.

关键词： Mesenchymal stem cells Growth factor Myocardium Cardiac remodeling

Model-based investigation on building thermal mass utilization and flexibility enhancement of air conditioning loads

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Building Simulation 2024年第8期17卷 1289-1308页

作者： Yue Sun Tianyi zhao shan Lyu Institute of Building Energy School of Infrastructure EngineeringDalian University of TechnologyDalian116024China School of Civil Engineering Chongqing UniversityChongqing 400045China

Building air conditioning systems(ACs)can contribute to the stable operation of power grids by participating in peak load shaving programs,but the participants need a fast and accurate zone temperature prediction model,e.g.,the detailed room thermal-resistance(RC)model,to improve peak shaving effect and avoid obvious thermal ***,when applying the detailed room RC model to multi-zone buildings,conventional studies mostly consider the heat transfer among neighboring rooms,which contributes little to the prediction accuracy improvement,but leads to complicated model structure and heavy ***,a distributed RC model is developed for multi-zone buildings in this *** to conventional models,the proposed model considers the total heat transfer between the building and the air,and ignores the heat transfer among indoor air in neighboring rooms through internal walls with heavy thermal mass,thereby having comparable temperature prediction accuracy,simpler structure,and stronger *** on the model,the effectiveness of passive pre-cooling strategies in reducing the air conditioning loads during peak periods is *** indicate that the thermal insulation performance of opaque building envelope is quite important to the flexibility enhancement of air conditioning *** an uninsulated building envelope,passive pre-cooling is useless for the peak load *** comparison,well insulated opaque building envelope enables the building thermal mass to be utilized through passive pre-cooling,which leads to the air conditioning loads during peak periods being further reduced by about 12%.

关键词： RC model passive pre-cooling internal thermal mass building energy flexibility