[1] To characterize lightning processes that produce terrestrial gamma ray flashes (TGFs), we have analyzed broadband (<1 Hz to 30 kHz) lightning magnetic fields for TGFs detected by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) satellite in 2004–2009. The majority (96%) of 56 TGF‐associated lightning signals contain single or multiple VLF impulses superposed on a slow pulse...

[1] The magnitudes of scattered fields produced during early/fast very low frequency (VLF) events observed at 13 closely spaced ( 65 km) sites are compared with those expected for sprite halo disturbances using a numerical model of wave propagation within the Earth-ionosphere waveguide. Three different early/fast events of varying magnitudes are analyzed using three different nighttime ambient ...

A chorus generation mechanism is discussed, which is based on interrelation of ELF/VLF noise-like and discrete emissions under the cyclotron wave-particle interactions. A natural ELF/VLF noise radiation is excited by the cyclotron instability mechanism in ducts with enhanced cold plasma density or at the plasmapause. This process is accompanied by a step-like deformation of the energetic electr...

Two mathematical methods, the Fourier and wavelet transforms, were used to study the short term cardiovascular control system. Time series, picked from electrocardiogram and arterial blood pressure lasting 6 minutes, were analyzed in supine position (SUP), during the first (HD1), and the second half (HD2) of 90◦ head down tilt and during recovery (REC). The wavelet transform was performed using...

"Cardiac and respiratory oscillations have been shown to interact with each other. This interaction could reflect autonomic nervous system functionality. Propofol-induced yawning during anesthesia induction seems to be associated with sympathetic activation. Presumptively, there is high linearity among interaction of different physiologic system behaviors. Recently, investigators used coher...

Viruses are usually thought to form parasitic associations with hosts, but all members of the family Polydnaviridae are obligate mutualists of insects called parasitoid wasps. Phylogenetic data founded on sequence comparisons of viral genes indicate that polydnaviruses in the genus Bracovirus (BV) are closely related to pathogenic nudiviruses and baculoviruses. However, pronounced differences i...

Several studies found that breathing abnormalities like OSA or Cheyne-Stokes ventilation are related to periodic changes in heart rate [1,2]. The influences of OSA on HRV analyzed by power spectral analysis have not been investigated until now. The purpose of this study was, therefore, to assess changes in the power spectrum of HRV during episodes of OSA as compared to a normal breathing patter...

The ionosphere plays a role in radio propagation that varies strongly with frequency. At extremely low frequency (ELF: 3–3000 Hz) and very low frequency (VLF: 3–30 kHz), the ground and the ionosphere are good electrical conductors and form a spherical Earth-ionosphere waveguide. Many giants of the electromagnetics community studied ELF-VLF propagation in the Earth-ionosphere waveguide, a topic ...

We sought to determine the influence of sympathoexcitation on dynamic cerebral autoregulation (CA), cerebrovascular reactivity, and ventilatory control in humans at high altitude (HA). At sea level (SL) and following 3-10 days at HA (5,050 m), we measured arterial blood gases, ventilation, arterial pressure, and middle cerebral blood velocity (MCAv) before and after combined α- and β-adrenergic...

introduction: spinal cord injuries are accompanied with significant demyelination of axons and subsequent locomotor dysfunction. to identify the extent of damage following electrolytic lesion of ventrolateral white matter, essential area for initiation of locomotor activity, we assessed demyelination as well as alteration in motor performance. moreover, the protective effect of estradiol as a c...