Showing papers by "Kazimierz Wielki University in Bydgoszcz published in 2005"

Mechanisms underlying spatial coding in a multiple-item Simon task.

Abstract: Choice responses are faster when target position and response side correspond than when they do not, even if target position is response-irrelevant. This Simon effect has also been observed in case of multi-item arrays. Generally, it is assumed that an automatically generated spatial response code is responsible for the effect. The referential-coding account assumes that this code is directly related to the target, although the moment of production of the code is not fully clear. The attention-shift account assumes that the code is directly related to the direction of the most recent attentional shift. An experiment was performed in which left or right target locations were indicated by arrows occurring before (precue), simultaneous with (simcue), or after (postcue) six-element arrays. Overt responses and EEG potentials were recorded. The Simon effect was present in all conditions, and decreased when responses were slower. No relation was found between amplitude of posterior lateralized components and the magnitude of the Simon effect. A posterior contralateral negativity was also found after presenting the arrays in the precue condition, which might reflect the reorienting of attention toward the target position. The results are more favorable to the referential-coding account although this account becomes very similar to the attention-shift hypothesis as the moment of formation of the spatial response code is related to effective target onset rather than to stimulus onset.

PCR multiplexing of nuclear microsatellite loci inQuercus species

Abstract: Simple sequence repeats have become the tool of choice in a wide range of studies of forest trees. Despite frequent use of multicolor fluorescent labeling DNA fragment analyzers, there are few procedures that reduce time and cost of the analyses by PCR multiplexing. Here we present an example of 2 multiplexes of 7 unlinked nuclear microsatellite loci to increase the efficiency of genotyping of large samples of oaks, which is extremely useful in population genetic studies.

Modeling kinetics of the austenite simultaneous decomposition into two bainitic products in the range of swing back

Abstract: A model of bainite transformation for two simultaneous reactions in the range of swing back is presented. The bainitic microstructure includes two different sheaves. The sheaves of first type had a midrib in the direction of the plates axes and form a butterfly shape. The second type of sheaves were of the grain boundary nucleated bainite. A mathematical model permitted dividing the kinetic curves and establishing separate time–temperature-transformation (TTT) diagrams for the individual structural components. The experimental data were obtained from dilatometric experiments. The assumptions of the model consist of the exponential relationship of the volume of the individual sub-plates and the autocatalytic coefficients related to the changes of nucleation rates. The results of the computation showed that the lengths of the individually formed sub-plates are dependent on the type of the structural component.

On application of neural networks for s-boxes design

Abstract: In the paper a new schedule of S-boxes design is considered We start from motivation from block cipher practice Then, the most popular S-box design criteria are presented, especially a possibility of application of Boolean bent-functions Finally, we propose integrating neural networks (playing a role of Boolean functions with appropriate properties) in the design process

Characterisation of the Rac/PAK pathway in Amoeba proteus.

Abstract: Molecular mechanisms underlying the unique locomotion of the highly motile Amoeba proteus still remain poorly understood. Recently, we have shown that blocking the endogenous amoebal Rac-like protein(s) leads to distinct and irreversible changes in the appearance of these large migrating cells as well as to a significant inhibition of their locomotion. To elucidate the mechanism of the Rac pathway in Amoeba proteus, we tested the effects of blocking the endogenous myosin I heavy chain kinase (MIHCK), one of the Rac effectors in Acanthamoeba castellanii and Dictyostelium discoideum, with anti-MIHCK antibodies in migrating amoebae, as well as the effect of inhibiting Rac and MIHCK on the actin polymerisation process. Antibodies against A. castellanii MIHCK detected an A. proteus protein with a molecular mass (ca. 95 kDa) similar to the A. castellanii kinase. The cellular distribution of MIHCK in A. proteus was very similar to those of Rac-like protein in amoebae and MIHCK in A. castellanii. Amoebae microinjected with anti-MIHCK antibodies moved slower and protruded fewer wide pseudopodia (5–6) than the control cells (9–10), resembling to some extent the phenotype of cells microinjected with anti-Rac antibodies. The in vitro studies indicate that the A. proteus Rac-like protein, but not the MIHCK isoform, is engaged in the regulation of the nucleation step of the actin polymerisation process. These observations suggest that MIHCK may be one of the effectors for Rac in these extremely large cells.

On the convergence of sequences of functions which are discontinuous on countable sets

Abstract: Let (X,TX) be a topological space and let (Y, dY ) be a metric space. For a function f : X → Y denote by C(f) the set of all continuity points of f and by D(f) = X\C(f) the set of all discontinuity points of f . Let C(X,Y ) = {f : X → Y ; f is continuous}, H(X,Y ) = {f : X → Y ; D(f) is countable}, H1(X,Y ) = {f : X → Y ; ∃h∈C(X,Y ) {x; f(x) 6= h(x)} is countable}, andH2(X,Y ) = H(X,Y )∩H1(X,Y ). In this article we investigate some convergences (pointwise, uniform, quasiuniform, discrete and transfinite) of sequences of functions from H(X,Y ), H1(X,Y ) and H2(X,Y ). Let (X,TX) be a topological space and let (Y, dY ) be a metric space. For a function f : X → Y , denote by C(f) the set of all continuity points of f and by D(f) = X \ C(f) the set of all discontinuity points of f . Let 2000 Mathematics Subject Classification. 26A15.