Effect of ramp bicycle exercise on exhaled carbon monoxide in humans.

The effect of exercise on the increase of exhaled CO in smokers compared to non-smokers has not been clarified yet. In this study we compared the dynamics of exhaled CO before, during and after exercise between smokers and non-smokers. A group of 8 smokers and a group of 8 non-smokers underwent a bicycle exercise in a ramp fashion to near maximum intensity.

Automated characterization of bending and expansion of a lattice of a Si substrate near a SiGe/Si interface by using split HOLZ line patterns.

A method to determine lattice parameters and parameters characterizing the bending strain of the lattice, the direction and magnitude of the displacement field of the bending strain, by using higher-order Laue zone (HOLZ) reflection lines observed in convergent-beam electron diffraction patterns is proposed. In this method, all of the parameters are simultaneously determined by a fit of two Hough transforms of experimental and kinematically simulated HOLZ line patterns. This method has been used to obtain two-dimensional maps of lattice parameter a, the direction and relative magnitude of the displacement field in a Si substrate near a SiGe/Si interface.

Modified scaled Fourier linear combiner in thoracic impedance cardiography.

New filtering algorithms; a modified scaled Fourier linear combiner (mSFLC) and a modified ensemble averaging (mEA) are proposed to remove the phase distortion of the impedance waveform caused by SFLC. Performance of the filters is assessed from the shape of the filtered waveform and the estimation of systolic time intervals. It was found that the mSFLC and mEA could compensate for drawbacks of the SFLC and precisely reproduce the impedance waveforms; however, misinterpretation and attenuation in the cardiac variables may be caused when abrupt changes or irregularities occur in the source waveform.

Modified thoracic impedance plethysmography to monitor sleep apnea syndromes.

Background And Purpose: In order to identify sleep disorders by thoracic impedance plethysmography (TIP), we propose several new techniques: the application of an adaptive filter, a scaled Fourier linear combiner (SFLC) to eliminate cardiac-derived fluctuation in the impedance waveform, and the use of heart rate variability (HRV) to ascertain whether the airflow is obstructed.

Patients And Methods: Laboratory simulation experiments on four healthy individuals and actual overnight measurements on five patients with sleep disorders were carried out. Amplified thoracic impedance change (DeltaZ), ECG, a phonocardiograph, a pneumotachograph and a standard polysomnograph were recorded.

Beat-to-beat evaluation of systolic time intervals during bicycle exercise using impedance cardiography.

In order to elucidate the beat-to-beat changes of the systolic time intervals (STI) during exercise, we proposed new techniques relating to an adaptive filter and detection algorithms for B- and X-points in the impedance cardiograph (ICG). Six male subjects underwent a ramp bicycle exercise up to maximum intensity during which an ECG, ICG and phonocardiogram (PCG) were continuously measured. Following the application of an adaptive filter, the scaled Fourier linear combiner (SFLC), to the first derivative (dZ/dt) of the base impedance (deltaZ) and PCG waveforms, the B- and X-points were automatically determined.

Validity of the adaptive filter for accurate measurement of cardiac output in impedance cardiography.

The purpose of this study was to assess the validity of an adaptive filter, the scaled Fourier linear combiner (SFLC), in the impedance cardiography (ICG). Eight healthy males underwent constant-load bicycle exercise at different intensities from unloaded to near maximal intensity. The stroke volume (SV) and cardiac output (Q) measured by ICG at each condition were compared with those by the CO2 rebreathing method.