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Chemical Research in Chinese Universities 2013年第4期29卷 638-641页

作者： LUO Hao-ming JIANG Rui-zhi YANG Xiao-hong CHEN ying-hong hong Tie WANG ying School of Pharmaceutical Sciences Jilin University Changchun 130021 P R. China Jilin Academy of Chinese Medicine and Material Medical Science Changchun 130012 P. R. China

Aiming at isolating and investigating the active ingredients of the aqueous extract from Panax ginseng which showed enhancing memory activity, the authors characterized one ingredient. To separate the oligosaecharides and polypeptides, a DEAE-Sephadex A-50 colum was used. The enhanced memory activity in mice was studied by Mirros water maze tesk in mice. The dose of oligosacchrides, polypeptides or Piracetam was 30 mg/kg per day with intraperitoneal administration. The oligosaccharides did not show enhancing memory effect, but polypeptides did show. This result demonstrates that the active ingredients of the aqueous extract from Panax ginseng which showed enhancing memory effect was polypeptides. The purification of the polypeptides was performed on a Sephadex G-25 column. A novel tetradeeapeptide was purified from the polypeptides and its structure was determined by liquid chromatography-eleetrospray ionization-quadrupole-time of flight-mass spectrometry（LC-ESI-Q-TOF-MS） with the amino acid sequence of Lys-Ser-Leu-Thr-Leu-Thr-Ser-Ser-Leu-Ser-Tyr-Thr-Asp-Ser.

关键词： Panax ginseng Polypeptide Tetradecapeptide Enhanced memory activity Liquid chromatography-tandemmass spectrometry(LC-MS/MS)

Dynamics and adaptive control of a dual-arm space robot with closed-loop constraints and uncertain inertial parameters

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Acta Mechanica Sinica 2014年第1期30卷 112-124页

作者： ying-hong Jia Quan Hu Shi-Jie Xu School of Astronautics Beihang University

A dynamics-based adaptive control approach is proposed for a planar dual-arm space robot in the presence of closed-loop constraints and uncertain inertial parameters of the payload. The controller is capable of controlling the po- sition and attitude of both the satellite base and the payload grasped by the manipulator end effectors. The equations of motion in reduced-order form for the constrained system are derived by incorporating the constraint equations in terms of accelerations into Kane＇s equations of the unconstrained system. Model analysis shows that the resulting equations perfectly meet the requirement of adaptive controller design. Consequently, by using an indirect approach, an adaptive control scheme is proposed to accomplish position/attitude trajectory tracking control with the uncertain parameters be- ing estimated on-line. The actuator redundancy due to the closed-loop constraints is utilized to minimize a weighted norm of the joint torques. Global asymptotic stability is proven by using Lyapunov＇s method, and simulation results are also presented to demonstrate the effectiveness of the proposed approach.

关键词： Space robot Dynamics. Adaptive control Closed-loop constraint Parameter uncertainty - Kane's equation

Dynamics of a spacecraft with large flexible appendage constrained by multi-strut passive damper

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Acta Mechanica Sinica 2013年第2期29卷 294-308页

作者： ying-hong Jia Shi-Jie Xu Quan Hu School of Astronautics Beihang University

This paper is concerned with the dynamics of a spacecraft with multi-strut passive damper for large flexible *** damper platform is connected to the spacecraft by a spheric hinge,multiple damping struts and a rigid *** damping struts provide damping forces while the rigid strut produces a motion constraint of the multibody *** exact nonlinear dynamical equations in reducedorder form are firstly derived by using Kane＇s equation in matrix *** on the assumptions of small velocity and small displacement,the nonlinear equations are reduced to a set of linear second-order differential equations in terms of independent generalized displacements with constant stiffness matrix and damping matrix related to the damping strut *** simulation results demonstrate the damping effectiveness of the damper for both the motion of the spacecraft and the vibration of the flexible appendage,and verify the accuracy of the linear equations against the exact nonlinear ones.

关键词： Dynamics·Motion constraints·Multi-strut passive damper·Kane's equation

The J_2 invariant relative configuration of spaceborne SAR interferometer for digital elevation measurement

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Acta Mechanica Sinica 2010年第4期26卷 643-651页

作者： Ming Xu ying-hong Jia Shi-Jie Xu Department of System Engineering DFH Satellite Co. Ltd. EO. Box 5616 Beijing 100094 China

A 3-craft formation configuration is proposed to perform the digital elevation model （DEM） for the distributed spacebome interferometric synthetic aperture radar （InSAR）, and it is optimized by the modified ant colony algorithm to have the best compatibility with J2 invariant orbits created by differential correction algorithm. The configuration has succeeded in assigning the across-track baseline to vary periodically and with its mean value equal to the optimal baseline determined by the relative height measurement accuracy. The required relationship between crafts＇ magnitudes and phases is formulated for the general case of interferometry measure from non-orthographic and non-lateral view. The J2 invariant configurations created by differential correction algorithm are employed to investigate their compatibility with the required configuration. The colony algorithm is applied to search the optimal configuration holding the near-constant across-track baseline under the J2 perturbation, and the absolute height measurement accuracy is preferable as expected.

关键词： InSAR Digital elevation model (DEM) J2 invariant orbit Differential correction algorithm Formation flying

Exploring Challenges in Developing a Smart and Effective Assistive System for Improving the Experience of the Elderly Drivers

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1133-1149页

作者： Sebin Jung hong-ying Meng Sheng-Feng Qin Department of Electronic and Computer Engineering Brunel University London Electrical QRD PM UX SBT Division General Motors Korea Northumbria School of Design Northumbria University

As the overall population ages, driving-related accidents and injuries, associated with elderly drivers, have risen. Existing research about elderly drivers mainly focuses on factual data collection and analysis, indicating the elderly＇s growing fatal accident rates and their different behaviours compared to younger drivers. However, few research has focused on design-led practical solutions to mitigate the elderly＇s growing fatal accidents, by consid- ering their usability and body conditions, afflicting the elderly, such as decreased vision, hearing, and reaction times. In this paper, first, current worldwide situations on growing fatal accident rates for elderly drivers is reviewed and the key impact factors are identified and discussed with regarding to usability and design trend in the automotive technology for elderly. Second, existing smart vehicle technology-based solutions to promote safe driving are explored and their pros and cons are discussed and anal- ysed. Most of solutions are not created by people with driving difficulties, which are caused by health problems most commonly afflicting the elderly. Thirdly, diverse design-led research activities are taken, such as a survey, observation, and interviews to gain new understanding of what kinds of driving problems elderly drivers have and demonstrate how new system concepts could be developed for the elderly＇s benefits. Finally, it is found that the elderly＇s low vision and late reaction are main factors causing their driving difficulties. Based on this finding, usable vehicle system design ideas have been proposed, by utilising facial expression sensing technology as a solution. The proposed solutions would ensure reducing both the elderly＇s driving problems and high fatal accident rates and provide a more enjoyable driving environment for the elderly population.

关键词： Elderly drivers Aging health conditionsDriving behaviours Vision impairment Cognitiveimpairment. Hearing loss Reflexes Fatal collision

Voluntary running delays primary degeneration in rat retinas after partial optic nerve transection

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Neural Regeneration Research 2019年第4期14卷 728-734页

作者： hong-ying Li Xi hong Mi Huang Kwok-Fai So Department of Anatomy School of Medicine Jinan University Guangdong-hongkong-Macao Institute of CNS Regeneration Ministry of Education CNS Regeneration Collaborative Joint Laboratory Jinan University Guangdong Key Laboratory of Brain Function and Diseases Jinan University Department of Ophthalmology and State Key Laboratory of Brain and Cognitive Sciences The University of Hong Kong

Running is believed to be beneficial for human health. Many studies have focused on the neuroprotective effects of voluntary running on animal models. There were both primary and secondary degeneration in neurodegenerative diseases, including glaucoma. However, whether running can delay primary or secondary degeneration or both of them was not clear. Partial optic nerve transection model is a valuable glaucoma model for studying both primary and secondary degeneration because it can separate primary(mainly in the superior retina) from secondary(mainly in the inferior retina) degeneration. Therefore, we compared the survival of retinal ganglion cells between Sprague-Dawley rat runners and non-runners both in the superior and inferior retinas. Excitotoxicity, oxidative stress, and apoptosis are involved in the degeneration of retinal ganglion cells in glaucoma. So we also used western immunoblotting to compare the expression of some proteins involved in apoptosis(phospho-c-Jun N-terminal kinases, p-JNKs), oxidative stress(manganese superoxide dismutase, MnSOD) and excitotoxicity(glutamine synthetase) between runners and non-runners after partial optic nerve transection. Results showed that voluntary running delayed the death of retinal ganglion cells vulnerable to primary degeneration but not those to secondary degeneration. In addition, voluntary running decreased the expression of glutamine synthetase, but not the expression of p-JNKs and MnSOD in the superior retina after partial optic nerve transection. These results illustrated that primary degeneration of retinal ganglion cells might be mainly related with excitotoxicity rather than oxidative stress; and the voluntary running could down-regulate excitotoxicity to delay the primary degeneration of retinal ganglion cells after partial optic nerve transection.

关键词： voluntary running optic nerve injury oxidative stress excitotoxicity JNKs primary degeneration secondary degeneration

Electrochemical reduction characteristics and mechanism of nitrobenzene compounds in the catalyzed Fe-Cu process

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Journal of Environmental Sciences 2006年第2期18卷 379-387页

作者： XU Wen-ying FAN Jin-hong GAO Ting-yao The National Engineering Research Center for Urban Pollution Control Tongji University Shanghai 200092 China

The reduction of the nitrobenzene compounds （NBCs） by the catalyzed Fe-Cu process and the relationship between the electrochemical reduction characteristics of NBCs at copper electrode and reduction rate were studied in alkaline medium（pH=11）. The catalyzed Fe-Cu process was found more effective on degradation of NBCs compared to Master Builder＇s iron. The reduction rate by the catalyzed Fe-Cu process decreased in the following order： nitrobenzene 〉4-chloro-nitrobenzene ≥m-dinitrobenzene ：〉 4-nitrophenol ≥2,4-dinitrotoluene 〉2-nitrophenol. The reduction rate by Master Builder＇s iron decreased in the following order： m-dinitrobenzene ≥4-chloro-nitrobenzene 〉4-nitrophenol 〉2,4-dinitrotoluene ≈nitrobenzene 〉2-nitrophenol. NBCs were reduced directly on the surface of copper rather than by the hydrogen produced at cathode in the catalyzed Fe-Cu process. The reduction was realized by the hydrogen produced at cathode and Fe（OH）2 in Master Builder＇s iron, It is an essential difference in reaction mechanisms between these two technologies. For this reason, the reduction by the catalyzed Fe-Cu depended greatly on NBC＇s electron withdrawing ability.

关键词： wastewater contaminated by NBCs electrochemical reduction characteristics catalyzed Fe-Cu process reduction mechanism

In situ characterization of natural pyrite bioleaching using electrochemical noise technique

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 117-126页

作者： Guo-bao Chen hong-ying Yang Hai-jun Li School of Metallurgy Northeastern University

An in situ characterization technique called electrochemical noise（ECN） was used to investigate the bioleaching of natural *** experiments were conducted in four active systems（sulfuric acid,ferric-ion,9k culture medium,and bioleaching solutions）.The ECN data were analyzed in both the time and frequency *** noise impedance spectra obtained from power spectral density（PSD）plots for different systems were compared.A reaction mechanism was also proposed on the basis of the experimental data *** bioleaching system exhibits the lowest noise resistance of 0.101 MΩ The bioleaching of natural pyrite is considered to be a bio-battery reaction,which distinguishes it from chemical oxidation reactions in ferric-ion and culture-medium（9k） *** corrosion of pyrite becomes more severe over time after the long-term testing of bioleaching.

关键词： bioleaching pyrite electrochemical noise biological oxidation chemical oxidation

Trehalose-6-phosphate phosphatases are involved in trehalose synthesis and metamorphosis in Bactrocera minax

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Insect Science 2022年第6期29卷 1643-1658页

作者： Jia Wang Huan Fan ying Li Tong-Fang Zhang ying-hong Liu College of Plant Protection Southwest UniversityChongqingChina College of Food Science Southwest UniversityChongqingChina

Trehalose is the principal sugar circulating in the hemolymph of insects,and trehalose synthesis is catalyzed by trehalose-6-phosphate synthase(TPS)and trehalose-6-phosphate phosphatase(TPP).Insect TPS is a fused enzyme containing both TPS do-main and TPP ***,many insects do not possess TPP genes as TPSs have re-placed the function of ***,TPPs are widely distributed across the dipteran insects,while the roles they play remain largely *** this study,3 TPP genes from notorious dipteran pest Bactrocera minax(BmiTPPB,BmiTPPCl,and BmiTPPC2)were identified and *** different temporal-spatial expression patterns of 3 BmiTPPs implied that they exert different functions in *** BmiTPPs were heterologously expressed in yeast cells,and all purified proteins exhibited enzy-matic activities,despite the remarkable disparity in performance between BmiTPPB and *** interference revealed that all BmiTPPs were successfully downregulated after double-stranded RNA injection,leading to decreased trehalose content and increased glucose ***,suppression of BmiTPPs significantly affected expression of down-stream genes and increased the mortality and malformation ***,these results indicated that all 3 BmiTPPs in *** are involved in trehalose synthesis and ***,these genes could be evaluated as insecticidal targets for managing ***,andevenforotherdipteranpests.

关键词： Bactrocera minax heterologous expression metamorphosis trehalose trehalose-6-phosphate phosphatase RNA interference

Gnetuhainin S, a New Resveratrol Dimer from Gnetum hainanense

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Chinese Chemical Letters 2002年第6期13卷 549-550页

作者： Shan ZHOU ying hong WANG Mao LIN Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050

Gnetuhainin S, a new resveratrol dimer, was isolated from the lianas of Gnetum hainanense C. Y. Cheng. Its structure and relative configuration were established on the basis of spectroscopic evidence.

关键词： Gnetuhainin S Gnetum hainanense Gnetaceae resveratrol dimer.