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43篇 您的检索式:作者名="Jingfang Liu"
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1A general methodology for mobility analysis of mechanisms based on constraint screw theory显示文摘It is well known that the traditional Grübler-Kutzbach formula fails to calculate the mobility of some classical mechanisms or many modern parallel robots,and this situation seriously hampers mechani-cal innovation.To seek an efficient and universal method for mobility calculation has been a heated topic in the sphere of mechanism.The modified Grübler-Kutzbach criterion proposed by us achieved success in calculating the mobility of a lot of highly complicated mechanisms,especially the mobility of all recent parallel mechanisms listed by Gogu,and the Bennett mechanism known for its particular difficulty.With wide applications of the criterion,a systematic methodology has recently formed.This paper systematically presents the methodology based on the screw theory for the first time and ana-lyzes six representative puzzling mechanisms.In addition,the methodology is convenient for judgment of the instantaneous or full-cycle mobility,and has become an effective and general method of great scientific value and practical significance.In the first half,this paper introduces the basic screw theory,then it presents the effective methodology formed within this decade.The second half of this paper presents how to apply the methodology by analyzing the mobility of several puzzling mechanisms.Finally,this paper contrasts and analyzes some different methods and interprets the essential reason for validity of our methodology.Zhen Huang JingFang Liu DaXing Zeng 2009Science China(Technological Sciences)2009,52,5:30
2Spatial and temporal variations of forest LAI in China during 2000-2010显示文摘Forests are crucial terrestrial ecosystems.Their leaf area index (LAI) is a key parameter determining the exchange of matter and energy between the atmosphere and the ground surface.In this study,MOD 09A1 and MCD 43A1 data were input into an inversion model based on the 4-scale geometric optical model to retrieve 8-d 500 m LAI products in China during the period 2000 to 2010.The resulting LAI product was validated using LAI measured in 6 typical areas.The spatial and temporal variations of forest LAI and its relationships with temperature and precipitation were analyzed.The results show that the accuracy of the 500 m LAI product was above 70% in the 6 typical areas,indicating the reliability of this product.From 2000 to 2010,forest LAI in northeast,north,and south central China showed increasing trends.However,forest LAI in southeast and parts of southwest China showed downward trends,mainly because of the significant decrease observed during the period 2008 to 2010.Annual mean forest LAI positively correlated with annual mean temperature (AMT) in northeastern China and negatively correlated with AMT in southwest China.It had positive correlations with annual total precipitation in central south and north China.The abnormal climate conditions in 2001 and 2009 caused forest LAI to be obviously lower than normal in regions south of the Qinling Mountains and Huaihe River.Annual mean LAI decreased by more than 1.0 in some areas.LIU YiBo JU WeiMin CHEN JingMing ZHU GaoLong XING BaiLing ZHU JingFang HE MingZhu 2012Chinese Science Bulletin2012,57,22:22
3Fuzzy adaptive robust control for space robot considering the effect of the gravity显示文摘Space robot is assembled and tested in gravity environment, and completes on-orbit service(OOS) in microgravity environment. The kinematic and dynamic characteristic of the robot will change with the variations of gravity in different working condition. Fully considering the change of kinematic and dynamic models caused by the change of gravity environment, a fuzzy adaptive robust control(FARC) strategy which is adaptive to these model variations is put forward for trajectory tracking control of space robot. A fuzzy algorithm is employed to approximate the nonlinear uncertainties in the model, adaptive laws of the parameters are constructed, and the approximation error is compensated by using a robust control algorithm. The stability of the control system is guaranteed based on the Lyapunov theory and the trajectory tracking control simulation is performed. The simulation results are compared with the proportional plus derivative(PD) controller, and the effectiveness to achieve better trajectory tracking performance under different gravity environment without changing the control parameters and the advantage of the proposed controller are verified.Qin Li Liu Fucai Liang Lihuan Gao Jingfang 2014Chinese Journal of Aeronautics2014,27,6:14
4Effect of soothing-liver and nourishing-heart acupuncture on early selective serotonin reuptake inhibitor treatment onset for depressive disorder and related indicators of neuroimmunology:a randomized controlled clinical trial显示文摘OBJECTIVE:To observe the effect of soothing-liver and nourishing-heart acupuncture on selective serotonin reuptake inhibitor(SSRIs) treatment effect onset in patients with depressive disorder and related indicators of neuroimmunology.METHODS:Overall,126 patients with depressive disorder were randomly divided into a medicine and acupuncture-medicine group using a random number table.Patients were treated for 6 consecutive weeks.The two groups were evaluated by the Montgomery-Asberg Depression Rating Scale(MADRS) and Side Effects Rating Scale(SERS) to assess the effect of the soothing-liver and nourishing-heart acupuncture method on early onset of SSRI treatment effect.Changes in serum 5-hydroxytryptamine(5-HT) and inflammatory cytokines before and after treatment were recorded and compared between the medicine group and the acupuncture-medicine group.RESULTS:The acupuncture-medicine group had significantly lower MADRS scores at weeks 1,2,4,and 6 after treatment compared with the medicine group(P < 0.01).The acupuncture group had significantly lower SERS scores at weeks 1,2,4,and 6 after treatment compared with the medicine group(P < 0.01).At 6 weeks after treatment,serum 5-HT in the acupuncture-medicine group was significantly higher compared with the medicine group(P <0.01).lnterleukin-6(IL-6) in the acupuncture-medicine group was significantly lower than that in the medicine group(P < 0.01),whereas there was no significant difference in IL-1(3 between the groups(P > 0.05).Anti-inflammatory cytokines IL-4 and IL-10 were significantly higher in the acupuncture-medicine group compared with the medicine group(P < 0.01,P < 0.05,respectively).CONCLUSION:The soothing-liver and nourishing-heart acupuncture method can effectively accelerate the onset of SSRI effects when treating depressive disorder and can significantly reduce the adverse reactions of SSRIs.Moreover,acupuncture can enhance serum 5-HT and regulate the balance of pro-inflammatory cytokines and anti-inflammatory cytokines.Liu Yi Feng Hui Mo Yali Gao Jingfang Mao Hongjing Song Mingfen Wang Shengdong Yin Yan Liu Wenjuan 2015Journal of Traditional Chinese Medicine2015,35,5:13
5Plasma metabolomic and lipidomic alterations associated with COVID-19显示文摘The pandemic of the coronavirus disease 2019(COVID-19)has become a global public health crisis.The symptoms of COVID-19 range from mild to severe,but the physiological changes associated with COVID-19 are barely understood.In this study,we performed targeted metabolomic and lipidomic analyses of plasma from a cohort of patients with COVID-19 who had experienced different symptoms.We found that metabolite and lipid alterations exhibit apparent correlation with the course of disease in these patients,indicating that the development of COVID-19 affected their whole-body metabolism.In particular,malic acid of the TCA cycle and carbamoyl phosphate of the urea cycle result in altered energy metabolism and hepatic dysfunction,respectively.It should be noted that carbamoyl phosphate is profoundly down-regulated in patients who died compared with patients with mild symptoms.And,more importantly,guanosine monophosphate(GMP),which is mediated not only by GMP synthase but also by CD39 and CD73,is significantly changed between healthy subjects and patients with COVID-19,as well as between the mild and fatal cases.In addition,dyslipidemia was observed in patients with COVID-19.Overall,the disturbed metabolic patterns have been found to align with the progress and severity of COVID-19.This work provides valuable knowledge about plasma biomarkers associated with COVID-19 and potential therapeutic targets,as well as an important resource for further studies of the pathogenesis of COVID-19.Di Wu Ting Shu Xiaobo Yang Jian-Xin Song Mingliang Zhang Chengye Yao Wen Liu Muhan Huang Yuan Yu Qingyu Yang Tingju Zhu Jiqian Xu Jingfang Mu Yaxin Wang Hong Wang Tang Tang Yujie Ren Yongran Wu Shu-Hai Lin Yang Qiu Ding-Yu Zhang You Shang Xi Zhou 2020National Science Review2020,7,7:9
6Mobility Analysis of Altmann Overconstrained Linkages by Modified Grübler-Kutzbach Criterion显示文摘Developing a general mobility method/formula is a hot topic lasting for more than 150 years in kinematics. It is necessary to apply any mobility method to puzzling overconstrained mechanisms for verification of its generality. Altmann linkages are such recognized puzzling mechanisms that their mobility analysis is of important significance. A necessary condition for judging a general mobility method is that the method can be fit for Altmann linkages. Firstly, this study classes Altmann linkages into 17 types in terms of the numbers and types of kinematic pairs, and then Altmann overconstrained linkages are further classified into 4 types. Secondly, the mobility of Altmann overconstrained linkages is systematically analyzed by the Modified Grübler-Kutzbach criterion based on screw theory, where passive freedoms are defined as limb passive freedoms and mechanism passive freedoms. In addition, the full-cycle mobility is judged, which overcomes the shortcoming of instantaneous property of screw theory. It is shown that Modified Grübler-Kutzbach criterion not only obtains the correct numerical mobility, but also gives the mobility character by resolving reciprocal screws for the constraint system. This study lays the foundation of verification for the generality of Modified Grübler-Kutzbach criterion. Besides, Altmann overconstrained linkages almost comprise all kinds of modern parallel mechanisms and some classical mechanisms, which provides an important reference for mechanism mobility calculation.LIU Jingfang LI Yanwen HUANG Zhen 2011Chinese Journal of Mechanical Engineering2011,24,4:7
7Applicability and Generality of the Modified Grübler-Kutzbach Criterion显示文摘A generally applicable criterion for all mechanism mobility has been an active domain in mechanism theory lasting more than 150 years. It is stated that the Modified Grübler-Kutzbach criterion for mobility has been successfully used to solve the mobility of many more kinds of mechanisms, but never before has anyone proven the applicability and generality of the Modified Grübler-Kutzbach criterion in theory. In order to fill the gap, the applicability and generality of the Modified Grübler-Kutzbach Criterion of mechanism mobility is systematically demonstrated. Firstly, the mobility research background and the Modified Grübler-Kutzbach criterion are introduced. Secondly, some new definitions, such as half local freedom, non-common constraint space of a mechanism and common motion space of a mechanism, etc, are given to demonstrate the correctness and broad applicability of the Modified Grübler-Kutzbach criterion. Thirdly, the general applicability of the Modified Grübler-Kutzbach criterion is demonstrated based on screw theory. The mobilities of the classical DELASSUS mechanisms and a modern planar parallel mechanism, are determined through the Modified Grübler-Kutzbach criterion, which are as examples to show the practical application of the Modified Grübler-Kutzbach criterion.LI Yanwen WANG Lumin LIU Jingfang HUANG Zhen 2013Chinese Journal of Mechanical Engineering2013,26,2:6
8General Order Principle for Multi-Bennett Linkages显示文摘Order analysis for multi-Bennett linkages is a difficult topic in kinematics. Traditional methods fail to obtain the order of multi-Bennett linkages due to considering the special geometric distributions among joint axes. An order principle for multi-Bennett linkages is presented. For a summated multi-Bennett linkage, three procedures are included in the order principle. Firstly, a homogeneous screw equation is obtained by taking linear superposition operations and then the maximum order is determined according to linear dependency of all screws. Secondly, two theorems are employed to determine the maximum order, where the first is used to judge the linear independency of four-system screws and the second is fit for identifying the linear independency of five-system screws. Lastly, all possible cases in the order range are considered until the valid order is screened out. For a syncopated multi-Bennett linkage, an equivalent summated model is built and then the order analysis is the same as that of summated linkages. In order to verify the effectiveness of the presented order principle, the orders of summated 5R and 6R linkages as well as a syncopated 6R linkage are analyzed. The computed orders of the former two summated linkages are both 4 and the computed order of the last syncopated 6R linkage is 5. The results coincide with the prototype data. The advantage of the proposed principle is that it can get the correct order of a multi-Bennett linkage without solving the geometric conditions of joint axes and has wide application in variety of multi-Bennett linkages.LIU Jingfang YU Yueqing HUANG Zhen HUANG Xiao'ou 2013Chinese Journal of Mechanical Engineering2013,26,2:5
9Phototransformation of nitrobenzene in the Songhua River:Kinetics and photoproduct analysis显示文摘Nitrobenzene (NB) pollution of the Songhua River caused by an explosion at a petrochemical plant in Jilin City,Jilin Province, China,attracted public concern over the fate of NB in the river.As one of the efforts to predict the fate of residual NB in the river,the kinetics and mechanism of phototransformation of NB in natural water from four sections of the Songhua River were investigated.It was found that photodegradation of NB in water proceeded via pseudo-first-order reaction kinetics under simulated ...WANG, Aimin HU, Chun QU, Jiuhui YANG, Min LIU, Huijuan RU, Jia QI, Rong SUN, Jingfang 2008Journal of Environmental Sciences2008,20,7:4
10Two unique C21-diterpenoid alkaloids from Aconitum carmichaelii显示文摘Two sulfonated diterpenoid alkaloids possessing different but related novel carbon skeletons,named aconidenusulfonine A(1)and 12,16-secoaconidenusulfonine A(2),respectively,were isolated as minor components from an aqueous extract of the lateral roots of Aconitum carmichaelii('Fu Zi').The structures of 1 and 2,representing the first two C21-diterpenoid alkaloids from nature,were determined by analysis of various spectroscopic data and chemical transformation,of which 1 was further proved by single-crystal X-ray diffraction.Especially,1 exhibited dose-depended analgesic activity consistent with the clinical function of Fu Zi.Jingfang Zhang Xiaoqiang Lei Yazi Wei Hui Liu Qinglan Guo Tiantai Zhang Jiangong Shi 2022Chinese Chemical Letters2022,33,12:4
11Mobility of the Myard 5R Linkage Involved in “Gogu Problem”显示文摘Since the traditional Grbler-Kutzbach criterion fails in many overconstrained mechanisms, developing a general mobility formula is a hot topic lasting for more than 150 years in mechanisms. GOGU systematically investigated various mobility methods, and pointed that the methods were not fit for two kinds of paradoxical overconstrained mechanisms. The mobility on the two kinds of mechanisms is regarded as 'Gogu problem' . The Modified Grbler-Kutzbach criterion has solved the mobility of the second kind of mechanisms in 'Gogu problem' , and has developed into a systematic mobility methodology. Myard 5R linkage is one of the single-loop mechanisms involved in 'Gogu problem' , its joint axes are distributed in space with special geometric conditions, which increases the difficulty of mobility analysis. The study is to calculate the global mobility of the Myard 5R linkage using the mobility methodology. Firstly, the mobility methodology based on screw theory is briefly introduced. Secondly, some homogeneous transforms are performed according to the D-H parameters and the invariance of the linkage plane symmetry is revealed, which provides an idea to judge a plane-symmetric loop. The special geometric features of the axes distribution are discussed as well. Finally, the global mobility of the Myard 5R linkage is determined by the Modified Grbler-Kutzbach criterion. The results show that the methodology can be applied to more paradoxical mechanisms.LIU Jingfang HUANG Zhen LI Yanwen 2009Chinese Journal of Mechanical Engineering2009,22,3:3
12A four-gene signature-derived risk score for glioblastoma:prospects for prognostic and response predictive analyses显示文摘Objective: Glioblastoma(GBM) is the most common primary malignant brain tumor regulated by numerous genes, with poor survival outcomes and unsatisfactory response to therapy.Therefore, a robust, multi-gene signature-derived model is required to predict the prognosis and treatment response in GBM.Methods: Gene expression data of GBM from TCGA and GEO datasets were used to identify differentially expressed genes(DEGs)through DESeq2 or LIMMA methods.The DEGs were then overlapped and used for survival analysis by univariate and multivariate COX regression.Based on the gene signature of multiple survival-associated DEGs, a risk score model was established,and its prognostic and predictive role was estimated through Kaplan–Meier analysis and log-rank test.Gene set enrichment analysis(GSEA) was conducted to explore high-risk score-associated pathways.Western blot was used for protein detection.Results: Four survival-associated DEGs of GBM were identified: OSMR, HOXC10, SCARA3, and SLC39A10.The four-gene signature-derived risk score was higher in GBM than in normal brain tissues.GBM patients with a high-risk score had poor survival outcomes.The high-risk group treated with temozolomide chemotherapy or radiotherapy survived for a shorter duration than the low-risk group.GSEA showed that the high-risk score was enriched with pathways such as vasculature development and cell adhesion.Western blot confirmed that the proteins of these four genes were differentially expressed in GBM cells.Conclusions: The four-gene signature-derived risk score functions well in predicting the prognosis and treatment response in GBM and will be useful for guiding therapeutic strategies for GBM patients.Mianfu Cao Juan Cai Ye Yuan Yu Shi Hong Wu Qing Liu Yueliang Yao Lu Chen Weiqi Dang XiangZhang Jingfang Xiao Kaidi Yang Zhicheng He Xiaohong Yao Yonghong Cui Xia Zhang Xiuwu Bian 2019Cancer Biology & Medicine2019,16,3:2
13Downregulation of WIF-1 by hypermethylation in astrocytomas显示文摘当一个 Wnt 对手和肿瘤 suppressor,而是 WIF-1 基因倡导者和 WIF-1 的低表示的 hypermethylation 激活异常地发信号的 Wnt 并且导致几个人的肿瘤的开发, Wnt 禁止的 factor-1 (WIF-1 ) 行动。由使用 RT-PCR, immunohistochemistry 和 methylation 特定的 PCR,我们在 4 正常大脑纸巾分析了 WIF-1 的表示和 methylation, 35 刚 resected 星细胞瘤纸巾和 4 根导出 glioblastoma 的房间线。WIF-1 mRNA 和蛋白质表示层次的重要 downregulation 与正常大脑纸巾相比在星细胞瘤纸巾被观察。在 WIF-1 downregulation 和星细胞瘤的病理学的等级之间的重要协会被发现。WIF-1 基因异常 methylation 在 35 中的 19 个被观察(54.29%) 肿瘤样品。倡导者 methylation 肿瘤显示出低 WIF-1 蛋白质和 mRNA 表示,而倡导者 unmethylation 肿瘤显示了高蛋白质和 mRNA 表示层次。而且,, WIF-1 mRNA 表示的完全的缺席在四根房间线被观察有 demethylating 代理人的处理, 5-aza-2-deoxycytidine,恢复 WIF-1 表示。我们的结果建议 WIF-1 基因经常是在由异常倡导者 methylation 的星细胞瘤的 silenced。这可以是在星细胞瘤 carcinogenesis 的重要机制。Zhuanyi Yang Ying Wang Jiasheng Fang Fenghua Chen Jingfang Liu Jun Wu Yanjin Wang Tao Song Feiyue Zeng Yihua Rao 2010Acta Biochimica et Biophysica Sinica2010,42,6:2
14OsbZIP72 Is Involved in Transcriptional Gene-Regulation Pathway of Abscisic Acid Signal Transduction by Activating Rice High-Affinity Potassium Transporter OsHKT1;1显示文摘We created CRISPR-Cas9 knock-out and overexpressing OsbZIP72 transgenic rice plants to gain a better understanding of the role and molecular mechanism of OsbZIP72 gene in stress tolerance,which has remained largely elusive.OsbZIP72 was expressed and integrated into rice transgenic plant genomes,and the OsbZIP72 transcript in overexpression lines was elicited by salinity,abscisic acid(ABA)and drought stresses.OsbZIP72 overexpressing plants showed higher tolerance to drought and salinity stresses,while knock-out transgenic lines showed higher sensitivity to these stresses.The differentially expressed genes(DEGs)from RNA-sequencing data encompassed several abiotic stress genes,and the functional classification of these DEGs demonstrated the robust transcriptome diversity in OsbZIP72.Yeast one-hybrid,along with luciferase assay,indicated that OsbZIP72 acted as a transcriptional initiator.Remarkably,electrophoresis mobility assay revealed that OsbZIP72 bound directly to the ABAresponsive element in the OsHKT1;1 promoter region and activated its transcription.Overall,our findings revealed that OsbZIP72 can act as a transcriptional modulator with the ability to induce the expression of OsHKT1;1 in response to environmental stress through an ABA-dependent regulatory pathway,indicating that OsbZIP72 can play a crucial role in the ABA-mediated salt and drought tolerance pathway in rice.WANG Baoxiang LIU Yan WANG Yifeng LI Jingfang SUN Zhiguang CHI Ming XING Yungao XU Bo YANG Bo LI Jian LIU Jinbo CHEN Tingmu FANG Zhaowei LU Baiguan XU Dayong Babatunde Kazeem BELLO 2021Rice science2021,28,3:2
15A polymorphism site in the pre?miR?34a coding region reduces miR?34aexpression and promotes osteosarcoma cell proliferation and migration显示文摘Honglin Lv Jingfang Pei Hongtao Liu Haiyan Wang Jun Liu 2014Molecular Medicine Reports2014,,6:1
16miR?181b as a key regulator of the oncogenic process and its clinicalimplications in cancer (Review)显示文摘Juan Liu Weifeng Shi Changping Wu Jingfang Ju Jingting Jiang 2014Biomedical Reports2014,,:1
17Down-regulated miR-625 suppresses invasion and metastasis of gastric cancer by targeting ILK显示文摘Ming Wang Chenglong Li Hui Nie Xin Lv Ying Qu Beiqin Yu Liping Su Jianfang Li Xuehua Chen Jingfang Ju Yingyan Yu Min Yan Qinlong Gu Zhenggang Zhu Bingya Liu 2012FEBS Letters2012,,16:1
18, Multiple replication origins with diverse control mechanisms in Haloarcula hispanica 显示文摘Zhenfang Wu Jingfang Liu Haibo Yang 2013Nucleic Acids Research2013,113,:1
19Tetrahedron显示文摘Connecting a triangle base and an apex forms a simplest polyhedron-that is,a tetrahedron.On account of their structural simplicity and stability,two common classes of tetrahedra-namely,M4L4 and M4L6 (M indicates anions or metal cations,L indicates ligands with C3 symmetry for M4L4 and C2 symmetry for M4L6,respectively)-can be readily constructed from (i) six straight edges through an edge-bridged strategy or (ii) four triangle faces through a face-capped strategy,by means of supramolecular or coordination assembly.The intrinsic cavities inside tetrahedra enable them to act as versatile hosts for encapsulating a variety of guests,which leads to a wide range of applications including molecular recognition,catalysis,sensing and so on.In this review,we intend to summarize specifically the work carried out in the realm of porous tetrahedral cages.It includes representative synthetic strategies for the preparation of tetrahedra along with a general summary on their structural features.Thereafter,we will highlight the state-of-the-art progress in various functions of tetrahedra,in addition to presenting a full overview of applications wherein we aim to provide new insights into the design and preparation of new topological geometric structures and functional materials on the basis of the simplest polyhedron-tetrahedron.Lin Wu Yusheng Chen Jingfang Pei Min Tang Shangshang Wang Zhichang Liu 2019Chinese Journal of Chemistry2019,37,8:1
20Down-regulated miR-625 suppresses invasion and metastasis of gastric cancer by targeting ILK显示文摘Ming Wang Chenglong Li Hui Nie Xin Lv Ying Qu Beiqin Yu Liping Su Jianfang Li Xuehua Chen Jingfang Ju Yingyan Yu Min Yan Qinlong Gu Zhenggang Zhu Bingya Liu 2012FEBS Letters2012,,16:1
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