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No full textPoznańClinical investigations yield huge amount of experimental data which need appropriate processing. High degree of their variability decreases quality of prognostic and classification results. Frequently problem of strong redundancy of variables incorporated into model occurs, produces computational instabilities and in multifactorial models makes the appropriate interpretation of obtained results hindered. In this paper we present the set of mathematical procedures used in comparative analysis of two treatment methods for patients with advanced cervical cancer: radiotherapy and combined treatment of ionizing irradiation and chemotherapy
No full textPoznańThis paper begins with a discussion of the general form and general CP- and CPT- transformation properties of the Lee-Oehme-Yang (LOY) effective Hamiltonian for the neutral kaon complex. Next, the properties of the exact effective Hamiltonian determined by the properties of the exact transition amplitudes for this complex are discussed. Using the Khalfin Theorem we show that contrary to the standard result of the LOY theory, the diagonal matrix elements of the effective Hamiltonian governing the time evolution in the subspace of states of an unstable particle and its antiparticle need not be equal at for t > t0 (t0 is the instant of creation of the pair) when the total system under consideration is CPT invariant but CP noninvariant. The unusual consequence of this result is that, contrary to the properties of stable particles, the masses of the unstable particle “1” and its antiparticle “2” need not be equal for t o t0 in the case of preserved CPT and violated CP symmetries. We also show that there exists an approximation which is more accurate than the LOY, and which leads to an effective Hamiltonian whose diagonal matrix elements posses properties consistent with the conclusions for the exact effective Hamiltonian described above
No full textPoznańSGI and YottaYotta have developed a new architecture for data grids that leverages globally-shared file systems, automated multi-site data locality management, and multi-site authentication and access control. This document presents results of studies comparing performance for the new architecture to that of conventional data grid architectures
No full textPoznańThe purpose of this article is to present an algorithm based on the simplification of the boundaries and coboundaries of cubes in Rn. We extend the algorithm of W. D Kalies, K. Mischaikow and G. Watson which can be found in the paper Cubical approximation and computation of homology published in Banach Center Publ. 47, 115-131 (1999)
No full textPoznańThe protein sequence is coded with the help of the triplets of nucleotides, each corresponding to one amino acid in a protein sequence. The triplet code of the coding sequences possesses some informative redundancy. Some triplets are more probable than others. The analogous redundancies appear in all natural languages. The non-equal frequency of the characters in plain text makes possible that entire words can be predicted given the context of the plain text. This is typical problem in cryptanalysis that a plain text is compressed before encrypting it in order to reduce the language redundancies. The nucleotides represent the natural units to discuss the redundancies in the coding sequences of natural genomes. The mutation pressure and selection pressure are the main factors responsible for the observed redundancies. Then, the nucleotide frequency in DNA seems to be the natural information weight. We show, that the probability of a nucleotide to stay nonmutated becomes another, the more efficient information weight. It has smaller redundancy although it is correlated with the nucleotide frequency. We have found the values of probability for nucleotide to stay non-mutated in the particular case of the Borrellia burgdorferi genome. In order to examine the usefulness of the new frequencies we used them in a problem of bit-string packing in a channel with a given capacity. We performed a computer experiment, in which we have generated all possible oligomers consisting of k nucleotides and we have shown, that if the number of bits of the information carried out by the oligomers does not exceed a given threshold value, the same as calculated for genes of the Borrelia burgdorferi genome, then the distribution of the generated oligomers resembles the one used by these genes
No full textPoznańThe method of exponentially correlated Gaussian (ECG) wave functions is extended to the case of multicenter molecular systems with nuclei arranged in a 3-dimensional space. A particular case of a four-center two-electron system, H 2+ 4 , is studied by means of the variational approach. The energies reported in this work are the most accurate available to date