The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform
Silvio Pflugi - One of the best experts on this subject based on the ideXlab platform.
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accelerated cardiac mr stress perfusion with radial sampling after physical exercise with an mr compatible supine Bicycle Ergometer
Magnetic Resonance in Medicine, 2015Co-Authors: Silvio Pflugi, Sebastie Roujol, Mehme Akcakaya, Keigo Kawaji, Murilo Foppa, Obby Heydari, Eth Goddu, Kraig V Kissinge, Sophie ErgAbstract:Purpose To evaluate the feasibility of accelerated cardiac MR (CMR) perfusion with radial sampling using nonlinear image reconstruction after exercise on an MR-compatible supine bike Ergometer. Methods Eight healthy subjects were scanned on two separate days using radial and Cartesian CMR perfusion sequences in rest and exercise stress perfusion. Four different methods (standard gridding, conjugate gradient SENSE [CG-SENSE], nonlinear inversion with joint estimation of coil-sensitivity profiles [NLINV] and compressed sensing with a total variation constraint [TV]) were compared for the reconstruction of radial data. Cartesian data were reconstructed using SENSE. All images were assessed by two blinded readers in terms of image quality and diagnostic value. Results CG-SENSE and NLINV were scored more favorably than TV (in both rest and stress perfusion cases, P 0.05). Conclusion We have demonstrated the feasibility of accelerated CMR perfusion using radial sampling after physical exercise using a supine Bicycle Ergometer in healthy subjects. For reconstruction of undersampled radial perfusion, CG-SENSE and NLINV resulted in better image quality than standard gridding or TV reconstruction. Further technical improvements and clinical assessment are needed before using this approach in patients with suspected coronary artery disease. Magn Reson Med 74:384–395, 2015. © 2014 Wiley Periodicals, Inc.
Sophie Erg - One of the best experts on this subject based on the ideXlab platform.
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accelerated cardiac mr stress perfusion with radial sampling after physical exercise with an mr compatible supine Bicycle Ergometer
Magnetic Resonance in Medicine, 2015Co-Authors: Silvio Pflugi, Sebastie Roujol, Mehme Akcakaya, Keigo Kawaji, Murilo Foppa, Obby Heydari, Eth Goddu, Kraig V Kissinge, Sophie ErgAbstract:Purpose To evaluate the feasibility of accelerated cardiac MR (CMR) perfusion with radial sampling using nonlinear image reconstruction after exercise on an MR-compatible supine bike Ergometer. Methods Eight healthy subjects were scanned on two separate days using radial and Cartesian CMR perfusion sequences in rest and exercise stress perfusion. Four different methods (standard gridding, conjugate gradient SENSE [CG-SENSE], nonlinear inversion with joint estimation of coil-sensitivity profiles [NLINV] and compressed sensing with a total variation constraint [TV]) were compared for the reconstruction of radial data. Cartesian data were reconstructed using SENSE. All images were assessed by two blinded readers in terms of image quality and diagnostic value. Results CG-SENSE and NLINV were scored more favorably than TV (in both rest and stress perfusion cases, P 0.05). Conclusion We have demonstrated the feasibility of accelerated CMR perfusion using radial sampling after physical exercise using a supine Bicycle Ergometer in healthy subjects. For reconstruction of undersampled radial perfusion, CG-SENSE and NLINV resulted in better image quality than standard gridding or TV reconstruction. Further technical improvements and clinical assessment are needed before using this approach in patients with suspected coronary artery disease. Magn Reson Med 74:384–395, 2015. © 2014 Wiley Periodicals, Inc.
Izumi Tabata - One of the best experts on this subject based on the ideXlab platform.
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prediction of vo2max with daily step counts for japanese adult women
European Journal of Applied Physiology, 2009Co-Authors: Nobuyuki Miyatake, Mitsuru Higuchi, Kazuko Ishikawatakata, Motohiko Miyachi, Izumi TabataAbstract:The purpose of the study was to develop a new non-exercise VO2max prediction model using a physical activity (PA) variable determined by pedometer-determined step counts (SC, steps day−1) in Japanese women aged 20–69 years old. Eighty-seven and 102 subjects were used to develop the prediction model, and to validate the new model, respectively. VO2max was measured using a maximal incremental test on a Bicycle Ergometer. SC was significantly related to VO2max (partial correlation coefficient r = 0.40, P < 0.001) after adjusting for BMI (kg m−2) and age (years). When the new prediction equation developed by multiple regression to estimate VO2max from age, BMI, and SC (R = 0.71, SEE = 5.3 ml kg−1 min−1, P < 0.001) was applied to the Validation group, predicted VO2max correlated well with measured VO2max (r = 0.81, P < 0.001), suggesting that SC is a useful PA variable for non-exercise prediction of VO2max in Japanese women.
Steve A Kautz - One of the best experts on this subject based on the ideXlab platform.
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A Split-Crank Bicycle Ergometer Uses Servomotors to Provide Programmable Pedal Forces for Studies in Human Biomechanics
IEEE Transactions on Neural Systems and Rehabilitation Engineering, 2010Co-Authors: H. Machiel F. Van Der Loos, Lise Worthen-chaudhari, Douglas Schwandt, David M. Bevly, Steve A KautzAbstract:This paper presents a novel computer-controlled Bicycle Ergometer, the TiltCycle, for use in human biomechanics studies of locomotion. The TiltCycle has a tilting (reclining) seat and backboard, a split pedal crankshaft to isolate the left and right loads to the feet of the pedaler, and two belt-driven, computer-controlled motors to provide assistance or resistance loads independently to each crank. Sensors measure the kinematics and force production of the legs to calculate work performed, and the system allows for goniometric and electromyography signals to be recorded. The technical description presented includes the mechanical design, low-level software and control algorithms, system identification and validation test results.
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a split crank servomotor controlled Bicycle Ergometer design for studies in human biomechanics
Intelligent Robots and Systems, 2002Co-Authors: H Machiel F Van Der Loos, Steve A Kautz, D Schwand, J Anderso, G Che, David M EvlyAbstract:This paper presents a novel computer-controlled Bicycle Ergometer, the TiltCycle, for use in human biomechanics studies of pedaling. The TiltCycle has a tilting (reclining) seat and backboard, a split crank to isolate the left and right loads to the feet of the cyclist, and two belt-driven, computer-controller motors to provide both assistance and resistance loads. Sensors measure the kinematics and force production of the pedaling work performed, as well as goniometer and electromyography signals from the lower limbs. The technical description includes the mechanical design, low-level software and control algorithms designed for studies in human lower-limb biomechanics and bilateral coordination, and concludes with validation testing and system identification results.
H J Dargie - One of the best experts on this subject based on the ideXlab platform.
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novel exercise protocol suitable for use on a treadmill or a Bicycle Ergometer
Heart, 1990Co-Authors: D Northridge, Strua F A Gra, Ia Ford, J Christie, James M Mclenacha, Derek T Connelly, J J V Mcmurray, S G Ray, E Henderso, H J DargieAbstract:Many exercise protocols are in use in clinical cardiology, but no single test is applicable to the wide range of patients' exercise capacity. A new protocol was devised that starts at a low workload and increases by 15% of the previous workload every minute. This is the first protocol to be based on exponential rather than linear increments in workload. The new protocol (standardised exponential exercise protocol, STEEP) is suitable for use on either a treadmill or a Bicycle Ergometer. This protocol was compared with standard protocols in 30 healthy male volunteers, each of whom performed four exercise tests: the STEEP treadmill and Bicycle protocols, a modified Bruce treadmill protocol, and a 20 W/min Bicycle protocol. During the two STEEP tests the subjects' oxygen consumption rose gradually and exponentially and there was close agreement between the Bicycle and the treadmill protocols. A higher proportion of subjects completed the treadmill than the Bicycle protocol. Submaximal heart rates were slightly higher during the Bicycle test. The STEEP protocol took less time than the modified Bruce treadmill protocol, which tended to produce plateaux in oxygen consumption during the early stages. The 20 W/min Bicycle protocol does not take account of subjects' body weight and consequently produced large intersubject variability in oxygen consumption. The STEEP protocol can be used on either a treadmill or a Bicycle Ergometer and it should be suitable for a wide range of patients.
