Wrocław University of Technology

About: Wrocław University of Technology is a education organization based out in Wrocław, Poland. It is known for research contribution in the topics: Laser & Computer science. The organization has 13115 authors who have published 31279 publications receiving 338694 citations.

Fingerprinting the substrate specificity of M1 and M17 aminopeptidases of human malaria, Plasmodium falciparum.

Abstract: BACKGROUND: Plasmodium falciparum, the causative agent of human malaria, expresses two aminopeptidases, PfM1AAP and PfM17LAP, critical to generating a free amino acid pool used by the intraerythrocytic stage of the parasite for proteins synthesis, growth and development. These exopeptidases are potential targets for the development of a new class of anti-malaria drugs. METHODOLOGY/PRINCIPAL FINDINGS: To define the substrate specificity of recombinant forms of these two malaria aminopeptidases we used a new library consisting of 61 fluorogenic substrates derived both from natural and unnatural amino acids. We obtained a detailed substrate fingerprint for recombinant forms of the enzymes revealing that PfM1AAP exhibits a very broad substrate tolerance, capable of efficiently hydrolyzing neutral and basic amino acids, while PfM17LAP has narrower substrate specificity and preferentially cleaves bulky, hydrophobic amino acids. The substrate library was also exploited to profile the activity of the native aminopeptidases in soluble cell lysates of P. falciparum malaria. CONCLUSIONS/SIGNIFICANCE: This data showed that PfM1AAP and PfM17LAP are responsible for majority of the aminopeptidase activity in these extracts. These studies provide specific substrate and mechanistic information important for understanding the function of these aminopeptidases and could be exploited in the design of new inhibitors to specifically target these for anti-malaria treatment.

Superelement-based modeling of load distribution in large-size slewing bearings

Abstract: The supporting structures in large-size slewing bearings are highly flexible. In order to choose the proper bearing and shape the load-carrying structure one must estimate the distribution of forces among the individual rolling elements. Advanced numerical models are needed for this. An original method of modeling the rolling element-track system is presented and its usefulness for modeling large-size bearings is demonstrated. The results of an exemplary analysis are presented in the form of graphs and figures. The superelement-based discrete bearing models are so far most comprehensive and take into account all the phenomena involved in the bearing-supporting structures system. The application of the finite-element method and the models based on the track-rolling element-track superelement made it possible to determine the effect of the deformability of the supporting structures and the nonuniformity of their flexibility on the loading of the rolling elements in the two-row bearing. The use of formulas which do not take into account the flexibility of the supporting structures to determine the distribution of the load among the rolling elements is unacceptable.

Characteristics of X-H···π Interactions: Ab Initio and QTAIM Studies

Abstract: The MP2/6-311++G(d,p) calculations were performed on several hydrogen-bonded systems. Different complexes were taken into account to analyze various types of hydrogen bonds, possessing different types of proton donors and proton acceptors as well as characterized by the broad range of the interaction energy. The Quantum Theory of Atoms in Molecules is applied. The results of the hybrid variational-perturbational approach are discussed. The unique properties of hydrogen bonds, where π-electrons act as the proton acceptor (X–H···π), are analyzed, and these interactions are compared with the other types of hydrogen bonds, mainly with C–H···Y interactions. It is shown that for X–H···π systems the ellipticity at the bond critical point of the proton···acceptor interaction is much greater than for the other types of hydrogen bonds. However, both X–H···π and C–H···Y interactions are characterized by the dominance of the dispersive energy.

Subordinated α-stable Ornstein–Uhlenbeck process as a tool for financial data description

Abstract: The classical financial models are based on the standard Brownian diffusion-type processes. However, in the exhibition of some real market data (like interest or exchange rates) we observe characteristic periods of constant values. Moreover, in the case of financial data, the assumption of normality is often unsatisfied. In such cases the popular Vasicek model, that is a mathematical system describing the evolution of interest rates based on the Ornstein–Uhlenbeck process, seems not to be applicable. Therefore, we propose an alternative approach based on a combination of the popular Ornstein–Uhlenbeck process with a stable distribution and subdiffusion systems that demonstrate such characteristic behavior. The probability density function of the proposed process can be described by a Fokker–Planck type equation and therefore it can be examined as an extension of the basic Ornstein–Uhlenbeck model. In this paper, we propose the parameters’ estimation method and calibrate the subordinated Vasicek model to the interest rate data.