Based on the periastron precession model to account for kHz QPO of the binary X-ray neutron star, proposed by Stella and Vietri, we ascribe the 15-60 Hz Quasi Periodic Oscillation (QPO) to the periastron precession frequency of the orbiting accreted matter at the boundary of magnetosphere-disk of X-ray neutron star (NS). The obtained conclusions include: all QPO frequencies increase with increa...

Physical exertions are related to sudden cardiac death following acute myocardial infarction (AMI). Abnormalities in the autonomic modulation during exercise were noted in animals with AMI that were susceptible to potentially lethal arrhythmias. This study was done to evaluate the changes in the autonomic activity during exercise and recovery in AMI patients with good exercise capacity, using s...

UNLABELLED Deep and slow breathing (DSB) is a central part of behavioral exercises used for acute and chronic pain management. Its mechanisms of action are incompletely understood. OBJECTIVES 1) To test the effects of breathing frequency on experimental pain perception in a dose dependent fashion. 2) To test the effects of breathing frequency on cardiorespiratory variables hypothesized to med...

It is generally recommended that an esophageal balloon-catheter possess an adequate frequency response up to 15 Hz, such that parameters of respiratory mechanics may be quantified with precision. In our experience, however, we have observed that some commercially available systems do not display an ideal frequency response (<8-10 Hz). We therefore investigated whether the poor frequency respons...

The protocol used for intermittent photic stimulation (IPS) may determine the likelihood of evoking a photoparoxysmal response (PPR). One-hundred and thirty-five electroencephalograms (EEGs) presenting PPRs, from 125 patients were studied in order to identify the most effective stimulation frequency to evoke a PPR and the effects of repetition of IPS on the occurrence of a PPR. Two stimulation ...

Autonomic cardiovascular control was characterized in conscious, chronically catheterized mice by spectral analysis of arterial pressure (AP) and heart rate (HR) during autonomic blockade or baroreflex modulation of autonomic tone. Both spectra were similar to those obtained in humans, but at approximately 10x higher frequencies. The 1/f relation of the AP spectrum changed to a more shallow slo...

This study provides evidence that activity-dependent synaptic enhancement at a neuromuscular junction modifies the characteristics of force production of the receiving muscle during rhythmic motor neuron discharge patterns. Long-lasting augmentation of the excitatory junction potentials (EJPs) quickens and strengthens the muscle response to a given motor pattern. We used the muscle gm6 of the c...

As a result of the complex blood flow patterns that occur in the arterial tree, certain regions of the vessel wall experience fluctuations in shear stress that are dominated by harmonic frequencies higher than the heart rate (11). To assess whether variations in frequency affect endothelial gene expression, the gene expression patterns of cultured porcine aortic endothelium exposed to three sin...

The reproducibility of baroreflex sensitivity (BRS in ms/mmHg; BRSf in mHz/mmHg) determined with respect to the coherence between the variability in systolic blood pressure (SBP) and inter-beat intervals (IBI) or heart rate (HR) was tested. SBP and IBI were recorded beat-to-beat for 5 min (Finapres, breathing at 0.33 Hz) in 116 subjects (aged 19-24 years) sitting at rest three times in periods ...

for many years it was believed that extremely lowfrequency electromagnetic field (elf-emf) do not have any significant biological effects. in this study, the influence of extremely low-frequency electromagnetic fields on the growth performance, serum antioxidant power and gastrointestinal structure of rainbow trout were evaluated. rainbow trout (17-18 g) were exposed to electromagnetic fields (...