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Design of 3D-printed Cable Driven Humanoid Hand Based on Bidirectional Elastomeric Passive Transmission

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Chinese Journal of Mechanical Engineering 2021年第4期34卷 225-235页

作者： Teru Chen Xingwei Zhao Guocai ma Bo Tao Zhouping yin State Key Laboratory of Digital manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Intelligent manufacturing System Technology Beijing Institute of Electronic System EngineeringBeijing 100854China

Motion control of the human hand is the most complex part of the human *** has always been a challenge for a good balance between the cost,weight,responding speed,grasping force,finger extension,and dexterity of prosthetic *** solve these issues,a 3D-printed cable driven humanoid hand based on bidirectional elastomeric passive transmission(BEPT)is designed in this paper.A semi-static model of BEPT is investigated based on energy conservation law to analyze the mechanical properties of BEPT and a dynamical simulation of finger grasping is *** a good imitation of human hand and an excellent grasping performance,specific BEPT is selected according to human finger grasping *** advantage of BEPT based humanoid hand is that a good balance between the price and performance of the humanoid hand is *** proved that the designed prosthetic hand’s single fingertip force can reach 33 N and the fastest fingertip grasping speed realized 0.6 s/180°.It also has a good force compliance effect with only 430g’s *** can not only grab fragile objects like raw eggs and paper cup,but also achieve strong grasping force to damage metal *** humanoid hand has considerable application prospects in artificial prosthesis,human-computer interaction,and robot operation.

关键词： Humanoid hand Bidirectional elastomeric passive transmission Artificial prosthesis

Optimization and mechanism of gold-bearing sulfide flotation

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Rare Metals 2014年第3期33卷 363-368页

作者： Zhong-mei Sun Chun-Bao Sun Ji-Zhen Wang Wan-Zhong yin School of Civil and Environmental Engineering University of Science and Technology Beijing Zijin Research Institute of Mining and Metallurgy School of materials & Metallurgy Northeastern University College of Zi Jin Mining Fuzhou University

In order to overcome the difficulty of extracting gold from gold-bearing sulfide ore by cyanide process flotation was adopted based on mineralogical analysis Mineralogy shows that gold particles are of superfine structure and mainly enclosed by sulfide ores. Primary gold-bearing sulfide ore is fine-grained pyrite and arsenopyrite. The paper describes the effects of ratios and dosage of activators and collectors on the recovery and grade of gold concentrate. A proper flotation flowsheet was then proposed based on experimental condition and closedcircuit test. The gold concentrate with the gold grade of25.14 g ton-1and the recovery of 86.94 % is obtained after one rougher, three cleaners, and four scavengers from fine grinding flotation process. Furthermore, the mechanisms of combined activators and combined collectors were studied by thermodynamic calculation, and structure-activity relationship of flotation reagent was also explained

关键词： Gold Pyrite Arsenopyrite Activator Combined reagent Flotation

Molecular Generation and Optimization of Molecular Properties Using a Transformer Model

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Big Data Mining and Analytics 2024年第1期7卷 142-155页

作者： Zhongyin Xu Xiujuan Lei mei ma Yi Pan School of Computer Science Shaanxi Normal UniversityXi'an 710119China Faculty of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Generating novel molecules to satisfy specific properties is a challenging task in modern drug discovery,which requires the optimization of a specific objective based on satisfying chemical ***,we aim to optimize the properties of a specific molecule to satisfy the specific properties of the generated *** matched Molecular Pairs(MMPs),which contain the source and target molecules,are used herein,and logD and solubility are selected as the optimization *** main innovative work lies in the calculation related to a specific transformer from the perspective of a matrix *** intervals and state changes are then used to encode logD and solubility for subsequent *** the experiments,we screen the data based on the proportion of heavy atoms to all atoms in the groups and select 12365,1503,and 1570 MMPs as the training,validation,and test sets,*** models are compared with the baseline models with respect to their abilities to generate molecules with specific *** show that the transformer model can accurately optimize the source molecules to satisfy specific properties.

关键词： molecular optimization transformer matched Molecular Pairs(MMPs) logD solubility

Will boreal winter precipitation over China increase in the future? An AGCM simulation under summer “ice-free Arctic” conditions

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Chinese Science Bulletin 2012年第8期57卷 921-926页

作者： ma JieHua WANG HuiJun ZHANG yin Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Climate Change Research Center Chinese Academy of SciencesBeijing 100029China Graduate University of Chinese Academy of Sciences Beijing 100049China

Frequent winter snowstorms have recently caused large economic losses and attracted wide *** snowstorms have raised an important scientific *** scenarios of future global warming,will winter precipitation in China increase significantly and produce more snow in the north? Using Coupled Model Intercomparison Project phase 3 (CMIP 3) model projections under the Special Report on Emissions Scenario A1B scenario,we generated a possible future Arctic condition,the summer (September) "ice-free Arctic" *** then used corresponding monthly sea surface temperature (SST) values and a set of CO 2 concentrations to drive an atmospheric general circulation model (AGCM),for simulating East Asian climate *** experimental results show that during the boreal winter (December-January-February;DJF),global surface air temperature would increase significantly under this scenario,producing substantial warming in Arctic regions and at high latitudes in Asia and North *** Siberian High,Aleutian Low and East Asian winter monsoon would all ***,because of increased transport of water vapor to China from the north,winter precipitation would increase from south to *** addition,the significant increase in winter temperature might cause fewer cold surges.

关键词：大气环流模式冬季降水中国北方北极地区模式模拟夏季东亚冬季风二氧化碳浓度

Uniform Invariance Principle of Discontinuous Systems with Parameter Variation

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Acta mathematicae Applicatae Sinica 2013年第4期29卷 717-724页

作者： Ju-mei WEI Rui ma Xiao-wu MU School of mathematics and Statistics Zhengzhou University

An extension of the invariance principle for a class of discontinuous righthand sides systems with parameter variation in the Filippov sense is proposed. This extension allows the derivative of an auxiliary function V, also called a Lyapunov-like function, along the solutions of the discontinuous system to be positive on some sets. The uniform estimates of attractors and basin of attractions with respect to parameters are also obtained. To this end, we use locally Lipschitz continuous and regular Lyapunov functions, as well as Filippov theory. The obtained results settled in the general context of differential inclusions, and through a uniform version of the LaSalle invariance principle. An illustrative example shows the potential of the theoretical results in providing information on the asymptotic behavior of discontinuous systems.

关键词： invariance principle Lyapunov functions discontinuous systems

Brucine Suppresses Breast Cancer Metastasis via Inhibiting Epithelial Mesenchymal Transition and matrix Metalloproteinases Expressions

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Chinese Journal of Integrative Medicine 2018年第1期24卷 40-46页

作者： LI Miao LI Ping ZHANG mei ma Feng Department of Geriatrics the First Affiliated Hospital of Bengbu Medical College Department of Chinese Medicine Tumor the Affiliated Provincial Hospital of Anhui Medical University

Objective： To examine the effect of brucine on the migration, invasion, adhesion and expressions of epithelial-to-mesenchymal transition （EMT） markers and matrix metalloproteinases （MMPs） in the highly metastatic breast cancer cell lines MDA-MB-231 and Hs578-T. Methods： MDA-MB-231 and Hs578-T cells were divided to 4 groups： the control group （0.1% DMSO）, and 25, 50 and 100 μmol/L brucine groups. The cell viability was determined using a CellTiter-Glo？ luminescent cell viability. The scratch wound healing assay and tanswell migration assay were used to determine the migration ability of these cells treated by different concentrations of brucine. The proliferation rate, invasive potential and adhesive ability were respectively performed by colony formation assay, transwell invasion assay and adhension assay. The protein and mRNA expressions of EMT biomarkers, MMP-2 and MMP-9 were investigated by real-time reverse transcription polymerase chain reaction and Western blot. Results： Compared with the control group, brucine had little effect on cell viability or proliferation （P〉0.05）, but led to a dose-dependent decrease on migration, invasion, adhension of MDA-MB-231 and Hs578-T cells （P〈0.01）. Furthermore, brucine increased the protein and mRNA levels of EMT markers such as E-cadherin and β-catenin in MDA-MB-231 and Hs578-T cells, and decreased the protein and mRNA levels of mesenychmal markers such as vimentin and fibronectin, as well as the expressions of MMP-2 and MMP-9 （all P〈0.01）. Conclusion： Brucine inhibited triple negative breast cancer cells metastasis potentially through EMT reversion and MMP-2 and MMP-9 inhibition.

关键词： brucine breast cancer metastasis epithelial mesenchymal transition matrix metalloproteinase

In vitro agonistic and antagonistic endocrine disrupting effects of organic extracts from waste water of different treatment processes

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Frontiers of Environmental Science & Engineering 2014年第1期8卷 69-78页

作者： Kaifeng RAO Na LI mei ma Zijian WANG State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety Key Laboratory of Nuclear Analytical Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

Effluents from wastewater treatment plant （WWTP） have been reported to have a broad spectrum of endocrine disrupting compounds （EDCs）. The majority of studies have focused on the occurrence of estrogenic activity, while ignoring nuclear hormone receptors （NRs） pathways. In the present study, a battery of in vitro yeast bioassays and a cell bioassay, including antagonistic and agonistic effects on estrogen receptor （ER）, androgen receptor （AR）, progesterone receptor （PR）, estrogen- related receptor （ERR） and aryl hydrocarbon receptor （AHR）, were conducted to evaluate the removal efficien- cies of EDCs by different treatment processes of a WWTP located in Beijing. Estrogenic, anti-estrogenic, anti- androgenic, anti-progesteronic, anti-ERR and the activa- tion of AHR activities were detected in samples from all treatment processes and the receiving water. The concen- tration of estrogenic contaminants with estradiol （E2） equivalent concentrations ranged from 0.82 x 10-9 to 3.54 x 10 9g Ee_EQ.L-1. The concentration of anti-estrogenic contaminants with 4-hydroxytamoxifen （4-OHT） equiva- lent concentrations ranged from 1.24 × 10-6 to 2.36 x 10-6 g 4-OHT-EQ.L-1. The concentration of anti-androgenic contaminants ranged from 2.21 x 10-s to 3.52 × 10-6g flutamide-EQ. L-1. The concentration of anti-progesteronic contaminants ranged from 3.15 x 10^-5 to 2.71 x 10^-4g RU486-EQ. L-1. The concentration of anti-ERR contami- nants ranged from 7.09 x 10-5 to 6.50 x 104 g 4-OHT-EQ × L^-10. The concentration of AHR activators ranged from 1.7 × 10-10 to 3.4 × 10^-10g TCDD-EQ-L-1. These processes including secondary clarifier, coagulation, as well as coal and sand filtration could eliminated 67.2% of estrogenic contaminants, 47.0% of anti-estrogenic contaminants, 98.3% of anti-androgenic contaminants, 88.4% of anti- progesteronic contaminants, 65.4% of anti-ERR contami- nants and 46.9% of AHR activators. WWTP effluents contain multiple receptor disruptors may have very complex adverse ef

关键词： waste water in vitro recombinant yeast assay,ethoxyresomfin-O-deethylase (EROD) receptor endocrine

Herschel Investigation of Cores and Filamentary Structures in the Perseus Molecular Cloud

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Research in Astronomy and Astrophysics 2022年第5期22卷 109-120页

作者： Chang Zhang Guo-yin Zhang Jin-Zeng Li Xue-mei Li National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Physics Guizhou UniversityGuiyang 550025China

Cores and filamentary structures are the prime birthplaces of stars,and play key roles in the process of star *** advances in the methods of multi-scale source and filament extraction,and in making highresolution column density map from Herschel multi-wavelength observations enable us to detect the filamentary network structures in highly complex molecular cloud *** statistics for physical parameters shows that core mass strongly correlates with core dust temperature,and M/L strongly correlates with M/T,which is in line with the prediction of the blackbody radiation,and can be used to trace evolutionary sequence from unbound starless cores to robust prestellar *** column densities of the filamentary structures are clearly related with mass per unit length(M_(line)),but are uncorrelated by three orders ranging from~10^(20) to~10^(22) cm^(-2) with *** width at half maximum has a median value of 0.15 pc,which is consistent with the 0.1 pc typical inner width of the filamentary structures reported by previous *** find 70%of robust prestellar cores(135/199)embedded in supercritical filaments with M_(line),>16 M⊙pc^(-1),which implies that the gravitationally bound cores come from fragmentation of supercritical *** the basis of observational evidence that the probability distribution function with power-law distribution in the Perseus south is flatter than in the north,the number of young stellar objects in the south is significantly less than that in the north,and dust temperature is *** infer that the south region is more gravitationally bound than the north region.

关键词： star forming regions-molecular clouds-interstellar filaments

Studies on marine Oil Spills and Their Ecological Damage

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Journal of Ocean University of China 2009年第3期8卷 312-316页

作者： mei Hong yin Yanjie Law and Politics School Ocean University of China Qingdao 266003 P. R. China School of Engineering and Arts Qingdao Technical College Qingdao 266555 P. R. China

The sources of marine oil spills are mainly from accidents of marine oil tankers or freighters, marine oil-drilling platforms, marine oil pipelines, marine oilfields, terrestrial pollution, oil-bearing atmosphere, and offshore oil production equipment. It is concluded upon analysis that there are two main reasons for marine oil spills: (I) The motive for huge economic benefits of oil industry owners and oil shipping agents far surpasses their sense of ecological risks. (II) marine ecological safety has not become the main concern of national security. Oil spills are disasters because humans spare no efforts to get economic benefits from oil. The present paper draws another conclusion that marine ecological damage caused by oil spills can be roughly divided into two categories: damage to marine resource value (direct value) and damage to marine ecosystem service value (indirect value). marine oil spills cause damage to marine biological, fishery, seawater, tourism and mineral resources to various extents, which contributes to the lower quality and value of marine resources.

关键词： marine oil spills ecological damage marine ecological safety damage to marine resource value damage to marine ecosystem service value