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Poznań, Poland

Bacteriocins are antimicrobial proteins or peptides produced by both Gram-positive and Gram-negative bacteria. Many of these metabolites are active towards closely related species, but some of them are able to inhibit bacteria not related with bacteriocin producer, including food pathogens such as Listeria monocytogenes or Clostridium botulinum. The most studied bacteriocins are those produced by lactic acid bacteria, but an increased interest in bacteriocins synthesized by propionibacteria has been observed in the last years. In this paper, the data on molecular characteristics and biochemical properties of actually known bacteriocins produced by this group of bacteria are presented. Source

Cieszynska A.,University Ekonomiczny | Regel-Rosocka M.,Poiitechnika Poznahska | Wisniewski M.,Poznan University of Technology
Przemysl Chemiczny | Year: 2011

A review, with 79 refs., of methods for solvent extraction of Ft group metals, esp. Pd(ll) ions present in trace amts., from spent solns., wastewater, anode slimes, as well as spent vehicle or industrial catalysts. Source

Krolikowska E.,Jastrzebska Spolka Weglowa | Sierpinska-Sawicz A.,University Ekonomiczny
Gospodarka Surowcami Mineralnymi / Mineral Resources Management | Year: 2016

In the article, the authors attempt to quantify the covenants, which are the special terms of the bond issuance programs, reducing a risk of the bondholders. The type and the character of the covenants depend on several circumstances like: financial situation of a bond issuer, industry risk, country risk or economic situation. The most common used covenants refer to several limitations like payments, taking out the loans, issuance of the next series of bonds, credit events, dividend payouts. The separate group of covenants are those which constitute a limitation of an assets disposal, a range of the investments, the mergers and acquisitions or those that refer to maintaining the rating. The belief that the bond issuance is the easiest way of rising the funds in comparison to a bank loan is not fully supported. The covenants have significant influence on a performance of a bond issuer. Some of the covenants cause losing a flexibility of a company and restrict a possibility of making the effective decisions which can lead to rising the risk of a bankruptcy. The limitations included in a bond issuance program could be particularly inconvenient for a company’s development and may demand the assets restructuring which range is hard to predict while a bond agreement is being signed. In terms of using the funds gained from bond issuance for an operating performance, the ability to go in a line with the covenants is less likely while the same funds will be spent on the investments which will generate the profits and amortisation in the future. It allows to gain the appropriate level of EBITDA as well as makes a bond repurchase possible. It is worth to add that the investors and the stock brokers who are responsible for a bond issuance program preparation have an influence on the quantity and quality of the covenants. They define the standard used covenants in the bond agreements. The knowledge and the negotiation skills of the managers have significant influence on the adjusting the bond contracts to the company and branch risk. © 2016 Gospodarka Surowcami Mineralnymi Mineral Resources Management. All rights reserved. Source

Suchy P.,Uzdrowisko Goczalkowice Zdroj Spolka Z O.o. | Dabrowska D.,University laski | Kucharski R.,University Ekonomiczny
Przeglad Geologiczny | Year: 2015

The article presents the assessment of the groundwater quality trend on the example of chlorides in the region of Goczałkowice Zdrój health resort. The data from the years 1977-2014 from two boreholes: GN-1, GN-2 were analysed. The trend assessment was made using the linear model, the fixed effect model and the robust statistic. The residts of these methods indicate a downward trend of chlorides concentration. Source

Using symmetrical or hybrid transformation Kedem-Katchalsky membrane transport equations (K-K) for ternary solutions can be transformed to symmetrical (Rij lub Lij) or hybrid (contain coefficients Hij, Wij, Sij, Nij, Kij or Pij) network form. Derivation of network form of K-K equations for homogeneous ternary non-electrolyte solutions containing Peusner's coefficients Hij (i, j element of {1, 2, 3}) and calculation of these coefficients for solutions consisting of solvent and two dissolved substances. Moreover comparison of these coefficients with coefficients Rij and Lij presented in the first and second part of the paper (Polim. Med.) was shown. Coefficients Hij (i, j element of {1, 2, 3}) can be calculated on the basis of experimentally determined transport parameters i.e. the hydraulic permeability coefficients (Lp), solute permeability (omega) and reflection (sigma). The research material was the membrane (Nephrophan) with known parameters for the transport of aqueous solutions of glucose and ethanol and the research tool was the formalism of Peusner's network thermodynamics (PNT) and K-K equation for ternary non-electrolyte solutions. Using the hybrid transformation of the Peusner's thermodynamic networks, the network form of K-K equations for ternary solution consisting of solvent and two dissolved substances was presented. Dependences of Peusner's coefficients Hij (i, j element of {1, 2, 3}) in the conditions of solutions homogeneity from the average concentration of one component of solution in the membrane (C1) with a constant value of second component (C2). Analysis of Peusner's coefficients Hij (i, j element of {1, 2, 3}) is a new tool, which can be used for examination of the membrane transport. The calculations proved, that the values of coefficients H12, H21, H22 and H32 are sensitive to the concentration and composition of the non-electrolyte solutions separated by the polymer membrane. Source

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