The secondary structure of phospholamban: a two-dimensional NMR study

Phospholamban (PLN) is an intrinsic membrane protein of 52 amino acids which regulates the Ca2+ pump of the sarcoplasmic reticulum of heart, slow-twitch and smooth muscle (SR): it is normally assumed to exist in the membrane as a homopentamer. A monomeric analogue of phospholamban PLN(C41F), in which Cys41 was replaced by a Phe, was synthesized and its conformation studied by 1H NMR spectroscopy in a 1:1 mixture of chloroform/methanol. Most of the resonances in the 1H NMR spectra were assigned. The work has shown that the C-terminal hydrophobic portion forms a very stable alpha-helix. The hydrophilic N-terminal part adopts an alpha-helix configuration which is much less stable except for the stretch containing the phosphorylation sites.     

Prototype of the 1/6 MOL Module of a Superpower Pulse Generator

This paper considers problems related to the creation (as part of the Baikal Program) of a super-power pulse generator intended for inertial confinement fusion applications and having pulse parameters of ～10 MV, ～50 MA, and ～150 ns. A MOL facility (3.7 MA, 5 MV, and 150 ns) with a six-module plasma opening switch (POS), operating as an output pulse compression stage, is being developed to test the circuit solutions of this generator. The design for the prototype of one POS module, referred to as the 1/6 MOL test bench, is presented. The results from experimental tests related to POS performance within the MOL facility are reported.     

Mathematical Model of the Accelerated Cooling of Metal in Thick-Plate Hot Rolling

Metallurgist - The paper describes the issues in predicting the consumer properties of thick-plate pipe products manufactured at the hot rolling mill 5000 of the Magnitogorsk Iron and Steel Works....     

Preparation of an exponentially rising optical pulse for efficient excitation of single atoms in free space

We report on a simple method to prepare optical pulses with exponentially rising envelope on the time scale of a few ns. The scheme is based on the exponential transfer function of a fast transistor, which generates an exponentially rising envelope that is transferred first on a radio frequency carrier, and then on a coherent cw laser beam with an electro-optical phase modulator. The temporally shaped sideband is then extracted with an optical resonator and can be used to efficiently excite a single (87)Rb atom.     

Measuring parameters of volume nanosecond pulsed discharge in air at atmospheric pressure

We report on the basic electrical characteristics of the volume nanosecond pulsed discharges in air at atmospheric pressure. The measurements of temperature were performed using spectral methods, whereas the electron density of plasma was measured using a multibeam Fabry-Perot interferometer. It is shown that, subject to maintaining the form of the volume discharge, the maximum electron density is 1.5 × 10¹³ cm^?3, which is comparable to the critical value in streamer discharges.     

Evaluation of the nitrogen oxide emission level for a steam supply with natural gas into the combustion chamber of a gas turbine unit

Numerical simulation results on the effect of the operation parameters for a combustion chamber of a combined-cycle plant (CCP) with steam injection [1] for the combined production of heat and electric energy upon a reduction in nitrogen oxide emission are represented. Calculations are carried out for lean mixtures with α = 1.2–1.4 and great steam consumptions of 30–42%. The reaction analysis has shown that the main contribution in NO _x formation was given by reactions with the advanced Zel’dovich thermal mechanism, and the reaction contribution with the participation of N₂O into the NO formation was an order of magnitude higher than that by the mechanism of the prompt NO formation. NO₂ does not form at high temperatures and only takes part in the conversion into NO in reactions with the participation of nitric acid. It is shown that the optimum choice of operation conditions for the combustion chamber of the CCP makes it possible to obtain the NO _x content in the combustion products in some mill^?1 (ppm). According to calculations, steam injection does not increase CO emission. A comparison with the experiment is given.     

Current stability of multilayer heterogeneous carbon-containing field-emission cathode–grid devices

Stability of current characteristics of a field-emission cell is analyzed. Experimental and simulated results are presented.