Effect of sinusoidal modulated currents and acute hypoxia on corticosterone content and activity of certain dehydrogenases in tissues of different rat organs during hypokinesia

The state of hypokinesia in rats was reproduced by keeping them for 30 days in special box cages that restricted their mobility in all directions. Results show the resistance to acute hypoxic hypoxia is increased. This is linked to the considerable rise in the reduced level of corticosterone in different organs and the succinate dehydrogenase activity in the liver and brain. The letter indicated the primary oxidation of succinate, which has great importance in the adaptation of the oxidative metabolism to acute oxygen insufficiency. The use of sinusoidal modulated currents in the period of hypokinesia promotes normalization of the indices for resistance of the rats to acute hypoxia

Monetary and Fiscal Policies in an Open Economy

The central theme of this paper is that international linkages between national economies influence, in fundamentally important ways, the effectiveness and proper conduct of national macroeconomic policies. Specifically, our purpose is to summarize the implications for the conduct of macroeconomic policies in open economies of both the traditional approach to open economy macroeconomics (as developed largely by James Meade, Robert Mundell, and J. Marcus Fleming) and of more recent developments. Our discussion is organized around three key linkages between national economies: through commodity trade; through capital mobility; and through exchange of national monies. These linkages have important implications concerning the effects of macroeconomic policies in open economies that differ from the effects of such policies in closed economies. Recent developments in the theory of macroeconomic policy have established conditions for the effectiveness of policies in influencing output and employment which emphasize the distinction between anticipated and unanticipated policy actions, the importance of incomplete information, and the consequences of contracts that fix nominal wages and prices over finite intervals. In this paper, we shall not analyze how these conditions are modified in an open economy. However, since our concern is with macro-economic policy, a principal objective of which is to influence output and employment, we shall assume that requisite conditions for such influence are satisfied.

Devil's staircase of incompressible electron states in a nanotube

It is shown that a periodic potential applied to a nanotube can lock electrons into incompressible states. Depending on whether electrons are weakly or tightly bound to the potential, excitation gaps open up either due to the Bragg diffraction enhanced by the Tomonaga - Luttinger correlations, or via pinning of the Wigner crystal. Incompressible states can be detected in a Thouless pump setup, in which a slowly moving periodic potential induces quantized current, with a possibility to pump on average a fraction of an electron per cycle as a result of interactions.Comment: 4 pages, 1 figure, published versio

Free-energy barrier to melting of single-chain polymer crystallite

We report Monte Carlo simulations of the melting of a single-polymer crystallite. We find that, unlike most atomic and molecular crystals, such crystallites can be heated appreciably above their melting temperature before they transform to the disordered "coil" state. The surface of the superheated crystallite is found to be disordered. The thickness of the disordered layer increases with superheating. However, the order-disorder transition is not gradual but sudden. Free-energy calculations reveal the presence of a large free-energy barrier to melting.Comment: AMS-Latex, 4 pages with 5 figures, submitted to Phys. Rev. Let