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Research for the Relationships between Body Acceleration and Energy Expenditure 被引量:1
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作者 ZHUYi RUANXing-yun SHENGYi XUZhi-rong GUOHai 《Chinese Journal of Biomedical Engineering(English Edition)》 2004年第4期145-151,共7页
During our research,It has been found that body acceleration has strong relationships with the human energy expenditure.This paper discusses the methods to assess physical activity and concludes that for accurate asse... During our research,It has been found that body acceleration has strong relationships with the human energy expenditure.This paper discusses the methods to assess physical activity and concludes that for accurate assessment of physical activity under free living conditions the recently introduced accelerometer looks most promising.We developed a new computerized machine to assess the body activity and energy expenditure.Test datas of the treadmill experiment,respiration experiment and 5-kilometer-running experiment have been archieved,we found that body acceration integrals with time has linear relations with body energy expenture. 展开更多
关键词 body acceleration Energy expenditure
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Estimation of speed-related car body acceleration limits with quantile regression
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作者 Jianli Cong Hang Zhang +6 位作者 Zilong Wei Fei Yang Zaitian Ke Tao Lu Rong Chen Ping Wang Zili Li 《Railway Sciences》 2024年第5期575-592,共18页
Purpose–This study aimed to facilitate a rapid evaluation of track service status and vehicle ride comfort based on car body acceleration.Consequently,a low-cost,data-driven approach was proposed for analyzing speed-... Purpose–This study aimed to facilitate a rapid evaluation of track service status and vehicle ride comfort based on car body acceleration.Consequently,a low-cost,data-driven approach was proposed for analyzing speed-related acceleration limits in metro systems.Design/methodology/approach–A portable sensing terminal was developed to realize easy and efficient detection of car body acceleration.Further,field measurements were performed on a 51.95-km metro line.Data from 272 metro sections were tested as a case study,and a quantile regression method was proposed to fit the control limits of the car body acceleration at different speeds using the measured data.Findings–First,the frequency statistics of the measured data in the speed-acceleration dimension indicated that the car body acceleration was primarily concentrated within the constant speed stage,particularly at speeds of 15.4,18.3,and 20.9 m/s.Second,resampling was performed according to the probability density distribution of car body acceleration for different speed domains to achieve data balance.Finally,combined with the traditional linear relationship between speed and acceleration,the statistical relationships between the speed and car body acceleration under different quantiles were determined.We concluded the lateral/vertical quantiles of 0.8989/0.9895,0.9942/0.997,and 0.9998/0.993 as being excellent,good,and qualified control limits,respectively,for the lateral and vertical acceleration of the car body.In addition,regression lines for the speedrelated acceleration limits at other quantiles(0.5,0.75,2s,and 3s)were obtained.Originality/value–The proposed method is expected to serve as a reference for further studies on speedrelated acceleration limits in rail transit systems. 展开更多
关键词 Car body acceleration Track status monitoring Speed-related acceleration limit Quantile regression Vehicle ride quality
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Gravity flow of pulsatile blood through a porous medium under periodic body acceleration and magnetic field in an inclined tube 被引量:1
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作者 Shakera Tanveer V. P. Rathod 《International Journal of Biomathematics》 2016年第2期139-157,共19页
Mathematical model for the pulsatile blood flow through a porous medium under the influence of periodic body acceleration for gravity flow along an inclined tube by considering blood as a couple stress, incompressible... Mathematical model for the pulsatile blood flow through a porous medium under the influence of periodic body acceleration for gravity flow along an inclined tube by considering blood as a couple stress, incompressible and electrically conducting fluid in the presence of magnetic field has been investigated. Analytical expressions for axial velocity, flow rate, fluid acceleration and shear stress are obtained by applying the Laplace and finite Hankel's transforms. The velocity profiles for various values of Hartmann number, couple stress parameters and the angle of inclination are shown graphically. Also the effects of body acceleration, Womerseley parameters and permeability parameters have been discussed. The results obtained in the present mathematical model for different values of the parameters involved in the problem show that the flow of blood is influenced by the effect of magnetic field, the porous medium and the inclination angle. The present model is compared with the other existing models. Through this theoretical investigation, the applications of magnetic field have also been indicated in the field of biological, biomedical and engineering sciences. 展开更多
关键词 Magnetic field body acceleration porous media couple stress fluid inclination angle gravity flow blood-borne diseases.
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CREG accelerates vasculogenesis in mouse embryonic stem sellsderived embryonic bodies
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作者 ZHANG Na,HAN Ya-ling,TIAN Xiao-xiang,ZHANG Xiao-lin, KAN Jian,YAN Cheng-Hui (Department of Cardiology,Cardiovascular Institute of PLA, Shenyang Northern Hospital.Shenyang,China) 《岭南心血管病杂志》 2011年第S1期193-194,共2页
Background Cellular repressor of ElA-stimulated genes(CREG) is homeostatic modulated gene,which regulate a number of cellular processes,including cell differentiation, motility and survival.Previous studies have demon... Background Cellular repressor of ElA-stimulated genes(CREG) is homeostatic modulated gene,which regulate a number of cellular processes,including cell differentiation, motility and survival.Previous studies have demonstrated that CREG was expressed in all three germ layers,suggesting that it might act as a vital regulator during embryonic developing.The aim of the present study was to investigate the role of CREG in an embryonic stem cell(ESC) differentiation model that recapitulates the developmental steps of vasculogenesis.Methods The ES cells were stably transfected either pCXN2-FLAG-CREG-IRES-EGFP plasmid or pDS1- shRNA-CREG plasmid to produce the CREG+/ES cells and CREG-siRNA/ES cells,respectively.Vasculogenesis was detected by whole mount immunostainings for CD31.Dil labeled acLDL staining assay was used to detect branching pseudopods in cultures in Matrigel.Real-time PCR and Western blot analysis were employed to determine expressions of VEGF and Flk-1.Results CREG +/ES-derived embryoid bodies(EBs) were found to form spontaneously a primitive vascular network after 6 days of differentiation.In contrast, wildtype EBs exhibit theirs vasculogenesis until 13 days of differentiation by whole mount immunostainings for CD31. CREG +/EBs developed more rapidly branching pseudopods at 9 days compared with that of wildtype EBs by Dil labeled acLDL staining assay.In contrast,CREG-siRNA/ES exhibits an undifferentiated morphogenesis associated with an increase in apoptotic cells in spite of being derived from LIF and feeder layers.Administration of CREG-siRNA/ES cells with recombinant CREG protein rescued the phenomena that CREG boosted vasculogenesis in a dose-dependent fasion. Mechanically,Real-time PCR and Western blot analysis revealed the expressions both VEGF and Flk-1 significantly in- creased in CREG+/EBs.Moreover,after treatment of CREG+ /EBs with neurtralizing antibody against VEGF,the rapid vasculogenesis was significantly repressed.Conclusions Our data strongely demonstrate that CREG play a pivotal role in accelerating vasculogenesis in development of ES cells. VEGF,as its important downstream effector,mediated this bio-function. 展开更多
关键词 CREG accelerates vasculogenesis in mouse embryonic stem sellsderived embryonic bodies STEM
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