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Glasses of the 6Na2O-(24-х)B2O3-70SiO2-хFe2O3 system with x ranging from 2 to 10 mol % are studied by dilatometry and X-ray powder diffractometry. The density of the glass is measured and the molar volume is calculated. The heat treatment of the glass is carried out at 550 and 700°C for 96 and 2 h, respectively. Magnetite is formed in the heat-treated glasses and its content increases with the growth of the Fe2O3 concentration. In the glasses containing from 4 to 8 mol. % of Fe2O3, cristobalite is formed after treatment at 700°C for 2 h. An increase in the density and the glass transition temperature and a decrease in the molar volume is observed with the growth of the iron oxide content. [ABSTRACT FROM AUTHOR]

Glasses of the 6Na2O · хB2O3 · (86 – x)SiO2 · 8Fe2O3 compositions, where x varies from 16 to 31 mol %, are studied by X-ray powder diffractometry and dilatometry. The glasses were preliminarily held at a temperature of 550°C for 8–144 h. It is determined that there are crystalline phases of magnetite and hematite in the studied glasses in addition to the amorphous component. The hematite content gradually decreases as the amount of SiO2 increases and it completely disappears when the SiO2 concentration is higher than 65 mol %. As the duration of the heat treatment increases, the amount of magnetite does not change. At the maximum duration of the heat treatment (144 h), crystallization of the silica phases—tridymite and cristobalite—is observed for all the studied glasses. The stability of the glass transition temperature of all glasses with an increase of the duration of the heat treatment indicates that the coexisting phases of phase-separated glass reach their equilibrium compositions after 8 hours. The crystallization of silica in the glasses is accompanied by a decrease in the glass transition temperature of the low-viscosity phase. [ABSTRACT FROM AUTHOR]

Abstract—The influence of exposure to mobile phone radiation on in vitro platelet aggregation has been studied. It has been shown that a 30-min exposure of blood samples to mobile phone radio frequency waves increases ADP-induced platelet aggregation in groups of healthy volunteers and patients with stroke, whereas platelet aggregation in JAKV617F-positive patients with polycythemia vera is significantly suppressed and is eventually completely inhibited. The mechanisms that underlie this phenomenon may be associated with cell oxidative stress and anomalies the JAK2 signal transduction pathway in malignized blood cells. The results indicate that it is important to set safety standards for the use of mobile devices by patients with various diseases. [ABSTRACT FROM AUTHOR]

Many-server queuing networks with general service and abandonment times have proven to be a realistic model for scenarios such as call centers and health-care systems. The presence of abandonment makes analytical treatment difficult for general topologies. Hence, such networks are usually studied by means of fluid limits. The current state of the art, however, suffers from two drawbacks. First, convergence to a fluid limit has been established only for the transient, but not for the steady state regime. Second, in the case of general distributed service and abandonment times, convergence to a fluid limit has been either established only for a single queue, or has been given by means of a system of coupled integral equations which does not allow for a numerical solution. By making the mild assumption of Coxian-distributed service and abandonment times, in this paper we address both drawbacks by establishing convergence in probability to a system of coupled ordinary differential equations (ODEs) using the theory of Kurtz. The presence of abandonments leads in many cases to ODE systems with a global attractor, which is known to be a sufficient condition for the fluid and the stochastic steady state to coincide in the limiting regime. The fact that our ODE systems are piecewise affine enables a computational method for establishing the presence of a global attractor, based on a solution of a system of linear matrix inequalities. [ABSTRACT FROM AUTHOR]

Glasses with the (8- x)NaO · xFeO ∙ 22BO ∙ 70SiO compositions, where the FeO content varies from 2 to 6 mol %, which were heat-treated at the temperatures of 550 and 700°С for 144 and 2 h, respectively, have been studied by dilatometry, electron microscopy, and X-ray powder diffractometry. It has been shown that, with an increase in the total concentration of FeO in the glass, there is a trend to the transition from an interconnected to a droplet-matrix phase-separated structure. The crystal line phases of FeO, FeSiO, and β-FeO are formed depending on composition, while the latter is observed only in the glass with the equivalent contents of NaO and FeO. There is a minimum on the glass transition temperature dependence of the composition at equimolar (4 mol %) contents of NaO and FeO. [ABSTRACT FROM AUTHOR]

Over the last 20 years, mass spectrometrybased proteomics has become an indispensable tool in the cellular and molecular life sciences. This has been enabled by the ‘soft ionisation’ techniques of electrospray and matrix-assisted laser desorption-ionisation, which allow the gentle ionisation and vaporisation of large, thermally labile biomolecules. Innovative instrumentation designs and biochemical strategies have brought success in the large-scale identification and quantification of proteins, as well as the characterisation of their complexes and post-translational modifications. This review describes the instrumentation used for proteomics research. It presents an overview of the current applications of mass spectrometry-based proteomics to the cellular and molecular life sciences, and discusses challenges that exist for research in the future. [ABSTRACT FROM AUTHOR]

The electrical properties of glasses of the 8NaO-(22- x)BO-70SiOFeO system, where x varies from 0.3 to 10 mol %, were studied. The glasses were heat treated at temperatures of 550 and 700°C for 144 and 2 h, respectively. When comparing the results of the measurements of the electrical resistance and the calculated values of activation energy of electrical conductivity of the iron-containing glasses and ironfree glass of the 8NaO · 22BO · 70SiO composition, it was concluded that the ionic conductivity is observed in the studied FeO-containing glasses. An increase in conductivity with increasing content of FeO was observed for glasses that was heat treated at 700°C for 2 h. [ABSTRACT FROM AUTHOR]