Spinal cords from 2- to 8-day-old rats, maintained in vitro, were used to investigate the effects of discrete electrical stimuli applied to the ventrolateral funiculus (VLF) on motor neuron activity recorded from the lumbar ventral roots. Short trains of stimuli (1-3 s) delivered to one VLF in the low cervical region elicited rhythmic activity that persisted for up to 30 s. Responses consisted ...

Lightning discharges radiate the bulk of their electromagnetic energy in the very low frequency (VLF, 3–30 kHz) and extremely low frequency (ELF, 3–3000 Hz) bands. This energy, contained in impulse-like signals called radio atmospherics or sferics, is guided for long distances by multiple reflections from the ground and lower ionosphere. This suggests that observed sferic waveforms radiated fro...

The product of the vlf-1 (very late factor 1) gene is required for expression of very late genes during the final phase of infection. To determine whether VLF-1 functions as a transcriptional activator, VLF-1 was overexpressed and purified by affinity and cation exchange chromatography. The addition of purified protein to transcription assays containing baculovirus RNA polymerase stimulated tra...

[1] Modulated high frequency (HF, 3–10 MHz) heating of the ionosphere in the presence of the auroral electrojet currents is an effective method for generating extremely low frequency (ELF, 3–3000 Hz) and very low frequency (VLF, 3–30 kHz) radio waves. The amplitudes of ELF/VLF waves generated in this manner depend sensitively on the auroral electrojet current strength, which varies with time. I...

Functional magnetic resonance imaging (fMRI) has become a leading tool in the evaluation of the human brain function. In fMRI the activation induced blood oxygenation changes in the brain can be detected with an inherent blood oxygen level dependent (BOLD) contrast. Even small blood oxygen fluctuations in a resting brain can be depicted with the BOLD contrast. This thesis focuses on characteriz...

BACKGROUND It is speculated that high saturated fat very low carbohydrate diets (VLCARB) have adverse effects on cardiovascular risk but evidence for this in controlled studies is lacking. The objective of this study was to compare, under isocaloric conditions, the effects of a VLCARB to 2 low saturated fat high carbohydrate diets on body composition and cardiovascular risk. METHODS Eighty th...

Spontaneous oscillations in cerebral haemodynamics studied with near-infrared spectroscopy (NIRS), become impaired in several pathological conditions. We assessed the spectral characteristics of these oscillations in 20 patients with falciparum malaria admitted to Ispat General Hospital, Rourkela, India. Monitoring included continuous frontal lobe NIRS recordings within 24 h of admission (Day 0...

The very low frequency electromagnetic (VLFEM) technique is well established for rapid geological mapping and detection of buried conductive targets. The technique makes use of signal radiation from military navigation radio transmitters. There are about 42 global ground military communication transmitters operating in VLF frequency in the range of 15–30 kHz. These stations, located around the ...

[1] Measurements of the input impedance of two very low frequency (VLF) transmitters in Antarctica are used to validate existing dielectric models for the ice substrate at these frequencies. Using a finite difference time domain approach, Maxwell’s equations are solved in the presence of dispersive media, representing the layers of ice which form the Antarctic ice sheet as a single-pole Debye m...

Very low frequency (VLF) remote sensing observations of multifaceted local and conjugate ionospheric perturbations from geographically identified and well-characterized oceanic lightning discharges are presented for the first time. Lightning-induced electron precipitation (LEP) events are shown to produce disturbances first in the conjugate hemisphere and subsequently in the hemisphere of the c...