Publications by authors named "R V Kozakov"

Objective: At the beginning of this century, a novel photopigment, melanopsin, was discovered in a sub-class of retinal ganglion cells and its action spectrum was described. Shortly after, it became evident that melanopsin is a major contributor to non-visual eye-mediated effects of light on e.g.

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An effect of a nonlocal plasma response caused by local laser radiation exciting atoms in resonant and metastable states is observed in a dc neon glow discharge. Starting at the perturbed position, spatially damped oscillations in the direction of the anode effecting all plasma quantities are created. Depending on the excitation of resonant or metastable atoms, the oscillations are phase-shifted by π.

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Life in 24-h society relies on the use of artificial light at night that might disrupt synchronization of the endogenous circadian timing system to the solar day. This could have a negative impact on sleep-wake patterns and psychiatric symptoms. The aim of the study was to investigate the influence of evening light emitted by domestic and work place lamps in a naturalistic setting on melatonin levels and alertness in humans.

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The spatiotemporal synchronization between two plasma instabilities of autonomous glow discharge tubes is observed experimentally. For this purpose, two tubes are placed separately and two chaotic waves interact with each other through a coupler. When the coupling strength is changed, the coupled oscillators exhibit synchronization in time and space.

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Resonance formation of the electron velocity distribution function (EDF) in an inert gas dc discharge at low pressures and small currents is analyzed on the basis of an accurate numerical solution of the Boltzmann kinetic equation in spatially periodic sinusoidally modulated striation-like fields. Calculations are performed for neon at pressures around 1 Torr . The dependences of the EDF, electron density and mean energy, and excitation rate on the electric field spatial period length are investigated.

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