Hippocampal damage induced by carbon monoxide poisoning and spreading depression is alleviated by chronic treatment with brain derived polypeptides

A model of acute carbon monoxide poisoning combined with spreading depression (SD) induced metabolic stress was used to examine the protective effects of cerebrolysin (CL) on the development of electrophysiological, behavioral and morphological signs of hypoxic damage. Capillary electrodes were implanted into the neocortex and hippocampus of anesthetized rats which were then exposed for 90 min to breathing of 0.8% to 0.5% CO, while 3 to 4 waves of cortical and hippocampal SD were elicited by microinjections of 5% KCl. Duration of SD-provoked depolarization of cerebral cortex and hippocampus was noted. Nine and 18 to 19 days later propagation of SD waves was recorded with the same electrodes and decrease of their amplitude was used as an index of brain damage which was significant in the hippocampus but not in the cortex. CL-treatment (2.5 ml/kg per day) started after CO administration and continued for 14 days significantly improved hippocampal recovery manifested by increased amplitude of SD waves. Behavioral tests performed 10 and 20 days after CO poisoning in the Morris water maze revealed better performance (escape latency 7 s) in the CL-treated than in untreated animals (14 s). Morphological analysis showed marked damage in the hippocampus consonant with electrophysiological and behavioral findings in the same animals. No apparent histological damage was found in rats exposed to CO inhalation alone without the additional SD-provoked depolarization. It is concluded that chronic CL-treatment enhances recovery of hippocampal tissue after hypoxic damage of intermediate severity.     

Environmentally safe fluoride cycle in tungsten technology. Substantiation of the production cycle with fluorine and hydrogen recycle

A fluoride cycle in tungsten technology is based on three processes: (i) electrochemical decomposition of HF in the KHF₂ + HF melt at 80–100°C with the separate evolution of gaseous fluorine and hydrogen; (ii) fluorination of the tungsten powder with evoluated fluorine at 300–350°C with the condensation of formed WF₆ in a liquid form at t = 2.5–3.0°C, and (iii) reduction of gaseous WF₆ with evoluated hydrogen at t = 580–600°C with the condensation of formed HF at +1°C and its use for the fluorine and hydrogen production, thereby ensuring their recycling in the cycle. The optimization of mentioned processes resulted in hardware-process implementations providing the formation of a large-scale plane and cylindrical billets in the industrial scale for deformation, as well as pipes, crucibles, and other products of various sizes made of tungsten with productivity of one process line of ~4.3 kg/h (>34 t/yr) with the fulfillment of environmental requirements. In contrast with the methods of powder metallurgy, the described technology ensures the formation of dense half-finished products and products made of pure tungsten with finer grain structures and almost unlimited sizes. Herewith, the specific power consumption for 1 kg of production lowers by a factor of 2.0–2.5. To increase the production efficiency, the simultaneous operation of four process lines in an automated mode is recommended.     

Theranostic Platforms Based on Silica and Magnetic Nanoparticles Containing Quinacrine,Chitosan, Fluorophores,and Quantum Dots

In this paper, we describe the synthesis of multilayer nanoparticles as a platform for the diagnosis and treatment of ischemic injuries. The platform is based on magnetite (MNP) and silica (SNP) nanoparticles, while quinacrine is used as an anti-ischemic agent. The synthesis includes the surface modification of nanoparticles with (3-glycidyloxypropyl)trimethoxysilane (GPMS), the immobilization of quinacrine, and the formation of a chitosan coating, which is used to fix the fluorophore indocyanine green (ICG) and colloidal quantum dots AgInS₂/ZnS (CQDs), which serve as secondary radiation sources. The potential theranostic platform was studied in laboratory animals.     

Influence of Silicon on the Properties of Aluminum Alloy Powders of the Silumin Type and the Mechanical Properties of Products Made from These Powders by Selective Laser Melting

Theoretical Foundations of Chemical Engineering - Technologies for the 3D printing of metallic powders are being increasingly extensively used around the world as alternatives to casting and...     

Phase Equilibria of a Pb–Sb–Ag Alloy during Vacuum Distillation

The saturated vapor pressures of lead, silver, and antimony are calculated for Pb–Ag and Pb–Sb alloys at temperatures of 1073–1773 and 823–1073 K, respectively. High ratios (p_Sb*/p_Pb*) × 10³ = 15.0–1.8 and p_Pb*/p_Ag* = 2.9 × 10³–74.0 create theoretical possibilities for sequential selective separation of these metals by vacuum distillation, during which the vapor is enriched in antimony and then lead and the liquid is enriched in silver. For vapor–liquid equilibrium (VLE) diagram, the lever rule (the rule of line segments) can be used to predict the amounts of substance, residue, and sublimate at a given temperature. Calculations of the ternary-alloy parameters can be performed by the Wilson equation using parameters obtained for the binary systems. The fractional Gibbs free energy (–ΔG_Pb/Sb/Ag = (2.1–22.4)/(1.9–25.5)/(18.1–50.0)), the enthalpy (ΔH_Pb/Sb/Ag = ±(0.2–16.9)/–(0.2–1.8)/(105–140) J/(K mol)), and the entropy (ΔS_Pb/Sb/Ag = (2.4–13.4)/(2.2–15.2)/(20.8–30.0) J/(K mol)) of the components of the Pb–Sb–Ag melts are calculated. As the fractions of metals in a starting alloy increase, the thermodynamic parameters decrease. The negative and positive values of the enthalpy indicate exothermic and endothermic processes in the melt during distillation of components, respectively. The calculated and experimental thermodynamic parameters are shown to agree satisfactorily: the standard relative deviation is 1.9% and the root-mean square deviation is 0.1 kJ/mol.     

Hemolytic Activity,Cytotoxicity, and Antimicrobial Effects of Silver Nanoparticles Conjugated with Lincomycin or Cefazolin

The overuse of antibiotics has led to the emergence of resistant bacteria. A good alternative is silver nanoparticles, which have antibacterial activity against Gram-negative and Gram-positive bacteria, including multidrug-resistant strains. Their combination with already known antibiotics has a synergistic effect. In this work, we studied the synthesis of conjugates of silver nanoparticles with two antibiotics, lincomycin and cefazolin. Albumin and glutathione were used as spacer shells with functional groups. The physicochemical properties of the obtained conjugates, their cytotoxicity and synergism of antimicrobial activity were studied. The 50% antimicrobial activity of the obtained samples was shown, which allows them to be recommended for use as topical drug preparations.     

Thermal Properties of Biological Tissue Gel-Phantoms in a Wide Low-Temperature Range

Journal of Engineering Physics and Thermophysics - It is often impossible or impractical to conduct experiments on cooling, freezing, and thawing during medical cryoexposures with using biological...     

Transition Dynamics in a Network Game with Heterogeneous Agents: the Stochastic Case

Automation and Remote Control - Stochastic parameters are introduced into a model of network games with production and knowledge externalities. The model was formulated by V. Matveenko and A....     

Magnetic Properties and Phase Composition of Metamaterials Based on an Opal Matrix with 3<Emphasis Type="Italic">d</Emphasis>-Transition Metal Particles

The magnetic properties of metamaterials based on an opal matrix with transition-metal (iron, nickel, cobalt) particles have been studied. Magnetization curves and magnetic hysteresis loops have been measured and the dependences of real and imaginary parts of magnetization have been determined using the dynamic ac susceptibility measuring procedure. Structural studies of metamaterials have been performed. The saturation magnetization and coercive force of the studied metamaterials have been found to depend weakly on the temperature. The temperature dependence of magnetic susceptibility at a temperature above 30 K can be described adequately by Curie–Weiss law and, at lower temperature, deviates from the law.     

Performance Evaluation of a Hybrid Computer Cluster Built on IBM POWER8 Microprocessors

Programming and Computer Software - This paper is devoted to the performance evaluation of a hybrid computer cluster built on IBM POWER8 CPUs and NVIDIA Tesla P100 GPUs. The architecture of the...