Propofol protected the heat stress-injured cells, at least partly, through upregulating MnSOD expression, effectively reducing the direct or indirect cell damage caused by oxidative stress.
A dynamical model based on the two-fluid dynamical equations with energy generation and loss is obtained and used to investigate the self-generated magnetic fields in high-temperature dense plasmas such as the solar core. The self-generation of magnetic fields might be looked at as a selforganization-type behavior of stochastic thermal radiation fields, as expected for an open dissipative system according to Prigogine's theory of dissipative structures.Thermal motion of electrons generates thermal radiation mainly by means of thermal bremsstrahlung emission in high-temperature plasmas. The higher the plasma temperature the more intense thermal radiation of the plasma. Thermal radiation causes substantial energy loss in high-temperature plasmas such as thermal nuclear fusion plasmas; for instance, the well-known Lawson condition is derived from the condition that the fusion energy compemsates the thermal bremsstrahlung emission loss.Here we are about to report some dissipative effect of thermal radiation loss in high-temperature dense plasmas such as thermal nuclear fusion plasmas.Generally, the elastic collision frequency ν ei between electrons and ion is high in high-temperature dense plasmas, for example, in the core of the Sun T e ∼ 10 7 K, n e ∼ 10 32 m −3 , we can eastimate ν ei ∼ 10 16 Hz, the plasma frequency ν pe ∼ 10 17 Hz. Such a frequent collision would destroy any collective plasma motion or coherent structure if the Sun were isolated adiabatically. In other word, the Sun would be in thermodynamic equilibrium if it was an isolated system. However, the Sun is in fact an open system: it not only gains thermal energy from the inelastic collisions between ions such as the proton-proton chain (or pp chain), but also loses energy by means of thermal radiation, for example, the loss rate of thermal radiation or the photon luminosity L ⊙ ∼ 4 · 10 33 erg/s (Bahcall, 1989). Therefore, the Sun may be far from equilibrium. The theory of dissipative structures (Prigogine, 1973; has shown that coherent behaviors may occur in a dissipative system. In fact, we have witnessed and are witnessing the dissipative structures in the convectve zone of the Sun, the convective cells. These are the coherent structures at the outer part of the Sun caused by thermal radiation dissipation which maintains the necessary temperature gradient. What are the dissipative structures in the source region?Roughly, nuclear fusion reactions take place within 0.3R ⊙ (Bahcall, 1989), where nuclear reactions (inelastic collisions between ions) first enhance stochastic motion of ions, the ions then transfer energy and momentum to electrons via elastic collision. The electrons lose energy and momentum through emitting photons via inelastic collision with ions and the thermal radiation escapes from the source region via radiation transfer. On average, the direction of the energy and momentum flux in the nuclear fusion region is therefore:This implies that electrons do not reach thermodynamic equilibrium with ions (T i > T e ), nor do photons with ...
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