The effect of short-term antiorthostatic hypokinesia on central and intracardiac hemodynamics and metabolism of a healthy person

The right parts of the heart and the radial artery were catheterized in healthy male volunteers before and 5 days after strict bedrest in antiorthostatic position of the body (-4.5 deg). After immobilization, most values of central circulation showed no essential changes; the only exceptions were indicates characterizing the inotropic myocardial condition. A shift in the direction of acidosis of a mixed character was noted in mixed venous blood, the beta lipoprotein content increased. A decrease in the arteriovenous difference in oxygen was encountered in blood draining from the heart (from the coronary sinus)

Photon assisted tunneling in pairs of silicon donors

Shallow donors in silicon are favorable candidates for the implementation of solid-state quantum computer architectures because of the promising combination of atomiclike coherence properties and scalability from the semiconductor manufacturing industry. Quantum processing schemes require (among other things) controlled information transfer for readout. Here we demonstrate controlled electron tunneling at 10 K from P to Sb impurities and vice versa with the assistance of resonant terahertz photons

The critical growth velocity for planar-to-faceted interfaces transformation in SiGe crystals

Crystal-melt interfacemorphological transformation of differently oriented SiGe crystals with different Ge concentrations was observed, and the effect of Ge concentration on critical growth velocity (V c) for the interfacemorphological transformation was investigated. A planar-to-faceted morphological transformation for the 〈110〉, 〈112〉, and 〈100〉 interfaces was observed. V c for planar-to-faceted transformation of the 〈110〉, 〈112〉, and 〈100〉 interfaces decreases nonlinearly with increasing Ge concentration. SiGe faceted interfaces can be attributed to the fact that the perturbation induced in a planar interface was amplified when the constitutional undercooled zone was formed at high growth velocities.Xinbo Yang gratefully acknowledges the Japan Society for the Promotion of Science (JSPS) Postdoctoral Fellowship for financial support. This work was partially funded by the Cabinet Office, Government of Japan through its “Funding Program for Next Generation World-Leading Researchers.

Zymography: developing of the enzyme soil activity visualization method

The enzymes produced by the soil biota are a key link in the regulation of biochemical processes. The soil enzyme activity can be visualized with zymography, a method based on using fluorescent substrates and obtaining two-dimensional images (zymograms). A variant of a zymographic measuring system has been proposed. Characteristics of lighting, photographic equipment and shooting modes, reagents preparation and calibration are presented. Preparing and analyzing soil samples of different texture (sand and clay loam) and processing the study results have been described. The ways of introducing the substrate are considered in this study, namely pipetting, short-time dipping, and saturation. An analysis of the kinetics of incubation of samples was carried out. The possibilities and disadvantages of the method were also considered and options for solving possible methodological problems during the analysis were proposed. The zymography is a promising method that allows comparing data with the results of other methods. The use of neural network technologies makes it possible to obtain the volumetric distribution of soil enzymes with high reliability. The soil zymography requires qualitative preparatory work and extreme accuracy during the analysis. It is necessary to ensure maximum contact between the substrate and the soil, as this is one of the key factors determining the quality of the results. The most optimal way to introduce the substrate is to saturate the membranes with substrate solution for 60 minutes. At this stage of the development of the method, it is not possible to establish a universal sample incubation time, since this depends on characteristics of both the studied soils and the experiment conditions. Also, it is necessary to document the conditions in detail for discussion the study results

Phenomenological analysis of K+ meson production in proton-nucleus collisions

Total and differential cross sections from literature, on the production of K+ mesons in pA interactions at projectile energies between T=0.8 and 2.9 GeV, covering the transition across the free nucleon-nucleon threshold at 1.58 GeV, have been investigated. From the target-mass dependence of the production cross sections no evidence for the expected change of the dominant reaction mechanism from two-step to direct kaon production was found. At T=1.0 GeV the A dependences of the total cross sections and of the most recent data from COSY-Juelich, differential cross sections measured under forward angles, are strongly different. The invariant K+ production cross sections show an overall exponential scaling behavior with the squared four-momentum transfer between the beam proton and the produced K+ meson for t< -0.05 GeV^2 independent of the beam energy and emission angle. The data from COSY-Juelich reveal a strongly different t dependence in the region of t>0 GeV^2. Further data at forward angles and different beam energies should be taken in order to explore this region of kinematically extreme conditions.Comment: 9 Pages, 11 Figure