ONTOLOGICAL MODEL OF A DATABASE OF INFORMATION-EDUCATIONAL PORTAL OF THE UNIVERSITY

According to the state program “Informational Society 2030”, it is planned to develop education on the basis of new progressive concepts of introducing the latest information technologies and scientific and methodological achievements into the educational process. In order to achieve goals, it is necessary to implement mobilization and effective use of staff and property and technical resources of the university. It is possible if there is purposeful modeling of the information and educational portal of the university. The choice and design of teaching technology are primarily determined by the type of students’ competencies and the characteristics of the planned learning outcomes for each level of competence (knowledge, skills, and experience). Constant improvement of EP content and educational technologies as a key factor of education services quality is a vital demand. The article considers the issues of the concept of ontology, IDEF-technologies and, based on the ontological model proposed in the article, the architecture of the database of the information and educational portal of the university is developed and classes and properties for the implementation of this model are defined, and a functional model of the university in IDEF0 is developed, which covers all types of university activities, integrates all information flows and forms a single information space

Interaction enthalpies of solid human serum albumin with water-dioxane mixtures: Comparison with water and organic solvent vapor sorption

Enthalpy changes (ΔHtot) on the immersion of dehydrated human serum albumin (HSA) into water-dioxane mixtures have been measured using a Setaram BT-2.15 calorimeter at 298 K. Thermodynamic activity of water was varied from 0 to 1. Calorimetric results are discussed together with the FTIR-spectroscopic data on water and organic solvent vapor adsorption/desorption isotherms on solid HSA. Dioxane sorption exhibits a pronounced hysteresis. Calorimetric and dioxane desorption dependencies consist of two parts. No dioxane sorption was observed in low water activity region (a w<0.5). At low water activities, the ΔHtot values are close to zero. At water activity about 0.5 the sharp exothermic drop of the interaction enthalpy values was observed. This exothermic drop is accompanied by the sharp increase in the amount of sorbed dioxane and additional water sorption (compared with that for pure water). Dioxane adsorption branch resembles a smooth curve. In this case, solid HSA binds more than 300 mol dioxane/mol HSA at low water activities. By using a water activity-based comparison we distinguished between dioxane-assisted and dioxane-competitive effect on water sorption. The obtained results demonstrate that the hydration "history" of solid protein is an important factor that controls as the state of protein macromolecule as well as the sorption of low-molecular organic molecules. © 2003 Elsevier B.V. All rights reserved

The native monomer of bacillus pumilus ribonuclease does not exist extracellularly

Copyright © 2018 Olga Ilinskaya et al. Supported by crystallography studies, secreted ribonuclease of Bacillus pumilus (binase) has long been considered to be monomeric in form. Recent evidence obtained using native polyacrylamide gel electrophoresis and size-exclusion chromatography suggests that binase is in fact dimeric. To eliminate ambiguity and contradictions in the data we have measured conformational changes, hypochromic effect, and hydrodynamic radius of binase. The immutability of binase secondary structure upon transition from low to high protein concentration was registered, suggesting the binase dimerization immediately after translocation through the cell membrane and leading to detection of binase dimers only in the culture fluid regardless of ribonuclease concentration. Our results made it necessary to take a fresh look at the binase stability and cytotoxicity towards virus-infected or tumor cells

Structure of complexes of poly-γ-benzyl-L-glutamate with water and dioxane molecules studied by IR spectroscopy and quantum chemical calculations

© 2014 Pleiades Publishing, Ltd. The structure of supramolecular complexes of poly-γ-benzyl-L-glutamate (PBG) with water and dioxane molecules during sorption from pure liquids and their binary mixtures is studied by IR spectroscopy and quantum chemical calculations. It is shown that the sorption sites of water and dioxane in PBG are different in nature. Water molecules are bound in the monomeric form to the carbonyl groups of the ester moieties of the side chains and the helical backbone of the peptide to form complexes with two hydrogen bonds. Dioxane molecules are sorbed in a large amount in the region of the side chains of PBG, causing their repacking with preservation of the helicity of the polypeptide backbone. Under simultaneous sorption of water and dioxane vapors, the binding of the latter increases the number of water molecules bound to the carbonyl groups of PBG. In this case, there is also an additional absorption of water molecules on the oxygen atoms of dioxane molecules. Calculations have shown that in the most probable configuration of the complexes, the water molecule simultaneously forms hydrogen bonds with the carbonyl groups of the side chain and the peptide backbone. Dioxane molecules do not penetrate to the peptide groups of helical backbone of PBG due to steric hindrance and are localized in the region of the benzyl moieties of the side chains; such complexes are stabilized by weak CH...O interactions

Creating carbon nanotubes microenvironment in surfactant water solutions

© 2017 Trans Tech Publications, Switzerland. The infrared absorption spectra of aqueous dispersions of carbon nanotubes in the presence of surfactants and alkali metal salts in the frequency range from 1000 cm-1 to 3000 cm-1 have been studied. The possibility of controlling the characteristics of local environment of carbon nanotubes by varying external electrolyte and modulation the surfactant micelle structure has been shown

On-Orbit Results of Photoelectron Current Measurement System in Low Earth Orbit on HORYU-IV Satellite

On-orbit photoelectron current experiment is one of the missions carried out with the less resource available from a HORYU-IV satellite, for measuring the current from metallic and insulator surfaces from air mass zero (AMO) spectrum. This is with the view to determined photoelectron potential of materials widely used in spacecraft in space. HORYU-IV also known as Arc Event Generator and Investigator satellite (AEGIS) is among HORYU satellite series of Kyushu Institute of Technology, which was launched on February 17, 2016 as a piggy-back on-board H-IIA rocket. The measurement system consists of current-voltage amplifier circuits for Au, Kapton and Black Kapton samples with varying gains and other discrete components. We present the analysis of the telemetry data obtained after the launch; validate the effectiveness of the design and verification processes. The results show that the current measured from Black kapton sample surface had 1.80 nA and 2.70 nA, corresponds to 69.1ᵒ and 75.1ᵒ minimum and maximum elevation angles respectively. This paper described the on-orbit result of PEC and its verification through ground tests

Secondary structure and colloidal stability of beta-casein in microheterogeneous water-ethanol solutions

© 2016 Elsevier LtdDynamic light-scattering (DLS), fluorescence spectroscopy (FS) and circular dichroism (CD) techniques were applied to study the influence of alcohol on beta-casein (b-CN) self-association and the secondary structure in a wide range of temperatures and ethanol concentrations. Temperature induced micellization and demicellization transitions of b-CN in water-ethanol solutions are revealed on the basis of the DLS data. The obtained results indicate that the association of b-CN at low and high alcohol concentrations proceeds through different mechanisms. It is suggested that the solvent microheterogeneity independently modulates both the secondary structure and the colloid properties of b-CN

Sorption of water vapor and acetonitrile by human serum albumin

The adsorption of water and acetonitrile (AN) vapor on a human serum albumin (HSA) from water-acetonitrile mixtures was measured by IR spectroscopy at 298 K in the water activity range from 0 to 0.98. It was established that the ability of the protein to bind water markedly decreases in the presence of acetonitrile. The dry protein sorbs ∼180 mol AN/mol HSA. The amount of AN sorbed linearly decreases with increasing humidity of the protein. An analysis of the absorption band belonging to the stretching vibration of the nitrile group of AN suggests that the environment of sorbed AN molecules changes from predominantly peptide to predominantly aqueous. The degree of helicity of proteins significantly increases in the presence of vapors of organic compounds. For the desorption branch, the difference in the degrees of helicity of a protein that sorbed pure water and a water-acetonitrile (AN) mixture (excess helicity) depends on the humidity, linearly increasing in passing from pure water to pure acetonitrile. During subsequent sorption-desorption cycles when the water is completely removed without removing AN, the excess helicity is independent of what branch is used, being determined only by the amount of AN in the protein sample

The influence of H-bonding on the enthalpies of solvation of proton acceptors in methanol

The influence of cooperative phenomena on the solvation of proton acceptors in methanol was studied. It was shown that solvation processes should be considered taking into account the dependence of the cooperative effect on the ability of the proton acceptor to form H-bonds with the solvent. A scheme for calculating the enthalpies of H-bond formation between proton acceptors and methanol associates is suggested. Copyright © 2005 by Pleiades Publishing, Inc