EJPAU, 2016, Volume 19, Issue 2

The bacterium Bacillus licheniformis M3, which is antagonistic towards pathogenic fungi and oomycetes, synthesizes at least two different isoforms of chitinases. The use of a three-stage purification procedure enabled the isolation of two of these isoforms: Chi1 and Chi2. Both of these enzymes have been classified as chitobiosidases of the exochitinase group. Chi1 exhibits a temperature optimum of 60°C and pH 6.0, and has the higher thermal stability. Chi2 exhibits its highest activity at 55°C and pH 7.0. Both of the studied chitinases exhibited highest activity towards colloidal chitin as substrate. Calcium and sodium ions caused a slight stimulation of the activity of both of these enzymes, whereas they were markedly inhibited by Hg²⁺ and Cd²⁺. Chi1 and Chi2 exhibited fungistatic activity towards Fusarium solani.

To summarize, B. licheformis M3 produces chitinases with fungistatic activity which could potentially find use as components of biopreparations for plant protection.

This article presents a new approach to monitor structural behavior of large historical timber structures. During the assessment of the method, data was collected at the research station located in the attic of the historical roof structure of a medieval church. The collected data was analyzed in terms of the influence of environmental actions (such as temperate change and wind load) and the results are presented in this article. This project is significant because the measurements of deflections of a very large structure are taken in situ. The article explains the complexity of such measurements as well as provides an overview of selected methods of measurement of structure deformations. A new application of draw-wire sensors as measurement instrument is presented with the results confirming the applicability of such sensors for deflection measurements

Using the monthly data from 26 equity investment funds operating continuously in Poland in 2005–2014, it was found that the financial crisis contributed to a significant reduction in the efficiency of the funds from 2008 onwards. Rates of return which funds achieved in the following years were many times lower than during the pre-crisis period. Risk mitigation strategy could cause that in times of the economic growth the performance of funds were weaker than the market, but oppositely better than the market in periods of crisis and economic slowdown. The negative impact of the crisis on funds’ performance is also confirmed by the declining values of the Sharpe index. The level of risk indicates that an additional risk taken by funds increased their rates of return in good times, but even more weakened them in the periods of economic downturn. The level of this correlation depends on the dynamics of changes in the stock market.