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No full textPoznańThe prevalence of clusters with the increased morbidity rate is the area of interest among epidemiologists. Not only does the identification of clusters require collecting precise epidemiological data but it also requires the application of reliable spatial statistics techniques. The identification of atypical clusters in this article is performed using data from the Polish Registry of Congenital Malformations (PRWWR) on children with isolated cleft lip with or without cleft palate; the study was carried out in the Wielkopolska Region (Greater Poland). For this purpose, Kulldorff Scan Statistics and the LISA method were used. Since each technique used in the study focuses on a slightly different aspect of spatial structure, the obtained clusters do not always completely overlap. This study presents and compares the efficiency and accuracy of these two non-standard methods of geo-static analysis in children living in the Greater Poland counties. The study has identified 5 agglomerations with an increased prevalence rate of the examined malformation, no statistically significant cluster has been detected. On the basis of the agglomerations, it was possible to compare the applicability of two statistical methods used in the study. Despite the fact that the located clusters do not always completely overlap, the study has proved similarity in qualifying particular counties for given clusters and areas outside the clusters. Taking into account its applicability and monitoring the process of spatial scanning, the Kulldorff method has occurred more universal and accurate in examining the children with congenital malformations
No full textPoznańA batch biotransformation process running in the presence of microorganisms cells revealing a specified enzyme activity has been considered. A non-linear deactivation model suggested by Do and Weiland has been taken into account for modeling of the process. Based on variational calculus computations aimed at finding an optimal selection of temperature conditions that ensure obtaining maximum conversion or minimum duration time necessary for its attaining have been carried out. The solutions were given and discussed for the stationary process, and for the active upper and lower temperature limitations. It has been proved that an application of microorganisms cells results in slowing down the reaction rate and shifting the initial temperature of the stationary profile to higher values. They are more pronounced the lower the permeability of the cell membrane is. In consequence, an extension of the process duration time is observed along the sections of the optimal profile while the lower temperature constraint usually becomes inactive
No full textPoznańUsing the self-consistent field theory (SCFT) in spherical unit cells of various dimensionalities, D, a phase diagram of a diblock, A-b-B, is calculated in 5 dimensional space, d = 5. This is an extension of a previuos work for d = 4. The phase diagram is parameterized by the chain composition, f, and incompatibility between A and B, quantified by the product χN. We predict 5 stable nanophases: layers, cylinders, 3D spherical cells, 4D spherical cells, and 5D spherical cells. In the strong segregation limit, that is for large χN, the order-order transition compositions are determined by the strong segregation theory (SST) in its simplest form. While the predictions of the SST theory are close to the corresponding SCFT extrapolations for d = 4, the extrapolations for d = 5 significantly differ from them. We find that the S5 nanophase is stable in a narrow strip between the ordered S4 nanophase and the disordered phase. The calculated order-disorder transition lines depend weakly on d, as expecte
No full textPoznańThe basis of a new method of automatic particle identification for CsI(Tl) scintillators is described and discussed. A useful tool for this purpose is PAW (Physics Analysis Workstation). PAW is an interactive and object-oriented utility for visualizing data, statistical analysis and some other tasks, which combines different CERN packages. A special procedure for CsI(Tl) data analysis, running under PAW in a batch mode, has been written and tested. The recent paper presents the main idea of the method and results obtained for simulated data. As the first step of the test, a relatively simple case of data has been examined. Obtained results indicate that for more complicated cases the procedure should work effectively as well
