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Opole, Poland

Opole University is a public university in the city of Opole. It was founded in 1994 from a merger of two parallel educational institutions. The university has 17,500 students completing 32 academic majors and 53 specializations. The staff numbers 1,380 - among them are 203 professors and habilitated doctors and 327 doctors.The university confers licentiate, master and doctoral degrees. Wikipedia.

Kubaczka A.,University of Opole
Journal of Membrane Science

Calculations of mass fluxes in multicomponent fluids based on the system of generalized Maxwell-Stefan equations (GMSE) is preferably used because Maxwell-Stefan (M-S) diffusion coefficients are symmetrical and have a clear physical meaning, as they reflect the binary friction forces between compounds in the system. For the calculation of the mass transport of a multicomponent fluid in the polymer basing on GMSE, it is necessary to have M-S diffusion coefficients. This paper proposes a method that allows their calculation using widely available self-diffusion coefficients and binary diffusion coefficients for infinitely diluted mixtures. The proposed method was compared with the method of J.S. Vrentas and Ch.M. Vrentas [Restrictions on friction coefficients for binary and ternary diffusion, Ind. Eng. Chem. Res. 46 (2007) 3422-3428] that allows to predict diffusion coefficients of the generalized Fick's equation (GFE) for ternary systems based on self-diffusion coefficients. In the computational experiment, values of molar fluxes of methanol and toluene in poly(vinyl acetate) calculated in a wide range of concentrations using both methods were compared. Because the proposed method calculates molar fluxes relative to the average molar velocity and the method cited above - mass fluxes relative to the average mass velocity, for the sake of clarity of the comparison, the derivation of J.S. Vrentas and Ch.M. Vrentas was repeated using molar concentrations and mole fractions instead of mass density and mass fractions and molar fluxes were obtained as in the proposed method. In both methods, derivatives of chemical potentials were calculated in the same way, using the UNIFAC-FV method for which equations on derivatives of activity coefficients were derived. The computational experiment showed that the values of fluxes calculated in ternary methanol-toluene-poly(vinyl acetate) system using both significantly different methods are very close. © 2014 Elsevier B.V. Source

Psychoactive drugs of fungal origin, psilocin, ibotenic acid, and muscimol among them have been proposed for recreational use and popularized since the 1960s, XX century. Despite their well-documented neurotoxicity, they reached reputation of being safe and nonaddictive. Scientific efforts to find any medical application for these hallucinogens in psychiatry, psychotherapy, and even for religious rituals support are highly controversial. Even if they show any healing potential, their usage in psychotherapy is in some cases inadequate and may additionally harm seriously suffering patients. Hallucinogens are thought to reduce cognitive functions. However, in case of indolealkylamines, such as psilocin, some recent findings suggest their ability to improve perception and mental skills, what would motivate the consumption of "magic mushrooms." The present article offers an opportunity to find out what are the main symptoms of intoxication with mushrooms containing psilocybin/psilocin, muscimol, and ibotenic acid. The progress in analytical methods for detection of them in fungal material, food, and body fluids is reviewed. Findings on the mechanisms of their biologic activity are summarized. Additionally, therapeutic potential of these fungal psychoactive compounds and health risk associated with their abuse are discussed. Copyright © 2013 by Lippincott Williams & Wilkins. Source

Piasecki R.,University of Opole
Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences

A multi-scale approach to the inverse reconstruction of a pattern's microstructure is reported. Instead of a correlation function, a pair of entropic descriptors (EDs) is proposed for a stochastic optimization method. The first of them measures a spatial inhomogeneity, for a binary pattern, or compositional one, for a greyscale image. The second one quantifies a spatial or compositional statistical complexity. The EDs reveal structural information that is dissimilar, at least in part, to that given by correlation functions at almost all discrete length scales. The method is tested on a few digitized binary and greyscale images. In each of the cases, the persuasive reconstruction of the microstructure is found. This journal is © 2011 The Royal Society. Source

Siodlak D.,University of Opole
Amino Acids

α,β-Dehydroamino acids are naturally occurring non-coded amino acids, found primarily in peptides. The review focuses on the type of α,β-dehydroamino acids, the structure of dehydropeptides, the source of their origin and bioactivity. Dehydropeptides are isolated primarily from bacteria and less often from fungi, marine invertebrates or even higher plants. They reveal mainly antibiotic, antifungal, antitumour, and phytotoxic activity. More than 60 different structures were classified, which often cover broad families of peptides. 37 different structural units containing the α,β-dehydroamino acid residues were shown including various side chains, Z and E isomers, and main modifications: methylation of peptide bond as well as the introduction of ester group and heterocycle ring. The collected data show the relation between the structure and bioactivity. This allows the activity of compounds, which were not studied in this field, but which belong to a larger peptide family to be predicted. A few examples show that the type of the geometrical isomer of the α,β-dehydroamino acid residue can be important or even crucial for biological activity. © 2014 The Author(s). Source

Godlowski W.,University of Opole
Astrophysical Journal

In the 1975 Hawley and Peebles proposed the use of three statistical tests for investigations of galaxy orientations in the large structures. Nowadays, it is considered as the standard method of searching for galactic alignments. In the present paper we analyzed the tests in detail and proposed a few improvements. Based on the improvements, a new method of analysis of the alignment of galaxies in clusters is proposed. The power of this method is demonstrated on the sample of 247 Abell clusters with at least 100objects in each. The distributions of the position angles for galaxies in each cluster are analyzed using statistical tests: χ2, Fourier, autocorrelation, and Kolmogorov test. The mean value of analyzed statistics is compared with theoretical predictions as well as with results obtained from numerical simulations. We performed 1000simulations of 247fictitious clusters, each with the numbers of galaxies the same as in the real clusters. We found that orientations of galaxies in analyzed clusters are not random, i.e., that there exists an alignment of galaxies in rich Abell galaxy clusters. © 2012. The American Astronomical Society. All rights reserved.. Source

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