Melting of high- and low-density polyethylene in mixtures with aluminum after plastic deformation under high pressure

Mixtures of low- and high-density polyethylene with aluminum were subjected to plastic deformation at a pressure of 0.5–4.0 GPa. DSC analysis showed that heating of samples at 110 and 140°C results in addition to the melting of polymers in the melting of ultrafine polymer crystallites at 40°C and also in chemical interaction at 80°C at the polymer–metal phase interface; crystallization of the polymer phase in deformed mixtures occurs at 14–18° higher than that of the initial polymers. Enthalpies of thermal processes in baric dependences reached extremum values at the pressures at which restructuring of the electron subsystem occurs in the deformed mixtures.     

From miRNA Target Gene Network to miRNA Function: miR-375 Might Regulate Apoptosis and Actin Dynamics in the Heart Muscle via Rho-GTPases-Dependent Pathways

MicroRNAs (miRNAs) are short, single-stranded, non-coding ribonucleic acid (RNA) molecules, which are involved in the regulation of main biological processes, such as apoptosis or cell proliferation and differentiation, through sequence-specific interaction with target mRNAs. In this study, we propose a workflow for predicting miRNAs function by analyzing the structure of the network of their target genes. This workflow was applied to study the functional role of miR-375 in the heart muscle (myocardium), since this miRNA was previously shown to be associated with heart diseases, and data on its function in the myocardium are mostly unclear. We identified PIK3CA, RHOA, MAPK3, PAFAH1B1, CTNNB1, MYC, PRKCA, ERBB2, and CDC42 as key genes in the miR-375 regulated network and predicted the possible function of miR-375 in the heart muscle, consisting mainly in the regulation of the Rho-GTPases-dependent signaling pathways. We implemented our algorithm for miRNA function prediction into a Python module, which is available at GitHub.     

Manufacture and measurement of combinatorial libraries of dielectric ceramics: Part II. Dielectric measurements of Ba1−xSrxTiO3 libraries

Applying combinatorial methods to materials science offers the opportunity to accelerate the discovery of more efficient dielectric ceramics. High-throughput methods have the potential to investigate the effects of a wide range of dopants on the dielectric properties, and to optimise existing systems, encouraging the short innovation cycles that the communications technology industry requires. The London University Search Instrument (LUSI) is a fully automated, high-throughput combinatorial robot that has the potential capability to produce large numbers of sintered bulk ceramic samples with varying composition in 1 day, as combinatorial libraries on alumina substrates. Ba_1−xSr_xTiO₃ (BST) libraries were produced by LUSI as a proof-of-principle, with x = 0–1 in steps of 0.1, and fired to 1350 and 1400 °C for 1 h. Part I of this paper described the manufacture and physical characterisation of BST libraries, showing a regular change in composition with x across the libraries. In this second part, the dielectric properties of BST libraries produced by LUSI are assessed at frequencies between 100 Hz and 1 MHz, and at temperatures between 150 and 500 K. Local piezoelectric properties were also characterised by scanning probe microscope (SPM). All measurements showed evidence of a clear functional gradient varying with x across the library, with measured _r corresponding to expected values for BST.     

Surface Properties of Films Composed of Aluminum and Its Alloy with Lanthanum

Protection of Metals and Physical Chemistry of Surfaces - Optical constants n and k of polycrystalline films of aluminum and Al–4.45 at % La alloy have been measured at room temperature. The...     

On electrocontact oxidation of iron nanocondensates

The transformation (under the effect of current passed) of a nanostructured metal-oxide coating produced by vacuum deposition of iron in an oxygen atmosphere at a pressure of 10⁻⁴ mm Hg on an amorphous glass substrate is studied by measuring voltammetric characteristics. In the freshly deposited film, a linear characteristic is observed that may correspond to direct quantum mechanical tunneling in thin oxide interlayers between metal nanograins. With an increase in the applied current density, when a certain threshold is reached, the conductivity of the conductor rapidly drops because of the thermo- and electrooxidation. In a degraded conductor at a prethreshold current density, a nonlinear voltammetric characteristic is observed, which may be related to the change in the mechanism of current flow restricted by the volume charge, as well as to the negative temperature resistance coefficient typical of fine-crystalline granular nanocomposites.     

Typical features of measurement of the flow rate of biological fluid in hemodialysis machines

We consider the typical features of application of the laser Doppler method for determination of blood flow rate in hemodialysis machines. We have analyzed the scattering characteristics of blood and blood flow in the blood tubing. We have obtained estimates of the basic parameters of the Doppler signal and we present the optical layout of the flowmeter.     

Examination of thermal processes and structure formation in twin‐arc servicing of wagon wheels using computer modelling

Research results of the diffusion welding of alloy VK20M and steel 5XHM in manufacturing bimetallic punching tools are given. Those stamps have higher reliability and durability, which were made using perforated pads.     

Isochoric Heat Capacity of Heavy Water at Subcritical and Supercritical Conditions

The heat capacity of heavy water was measured in the temperature range from 294 to 746 K and at densities between 52 and 1105 kg·m^–3 using a high-temperature, high-pressure adiabatic calorimeter. The measurements were performed at 14 liquid and 9 vapor densities between 52 and 1105 kg·m^–3. Uncertainties of the measurements are estimated to be within 3% for vapor isochores and 1.5% for the liquid isochores. In the region of the immediate vicinity of the critical point (0.97T/T _c1.03 and 0.75/_c1.25), the uncertainty is 4.5%. The original C _V data were corrected and converted to the new ITS-90 temperature scale. A parametric crossover equation of state was used to represent the isochoric heat capacity measurements of heavy water in the extended critical region, 0.8T/T _c1.5 and 0.35/_c1.65. The liquid and vapor one- and two-phase isochoric heat capacities, temperatures, and saturation densities were extracted from experimental data for each measured isochore. Most of the experimental data are compared with the Hill equation of state, and the overall statistics of deviations between experimental data and the equation of state are given.