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Sharma P.S.,Polish Academy of Sciences | D'Souza F.,University of North Texas | Kutner W.,Polish Academy of Sciences | Kutner W.,Cardinal Stefan Wyszynski University in Warsaw
TrAC - Trends in Analytical Chemistry | Year: 2012

Environmental and health safety requires thorough determination of hazardous compounds and drugs of abuse. In determinations of these analytes, traditional instrumental analytical techniques often suffer from tedious assay procedures. Biosensors are simpler to construct and faster in use, so they can better meet the analytical demands in determination of these biohazards. However, their stability and reproducibility when operating under harsh conditions are poor, so artificial recognition units have become attractive as replacements for natural receptors in sensing applications. Molecular imprinting is one of the most powerful tools for preparing materials that can bind analytes reversibly and selectively in the presence of their interferents. This review critically evaluates the development of chemical sensing of biohazards and drugs of abuse using the molecular-imprinting approach to recognition in combination with different ways of analytical signal transduction. We compile analytical parameters of the molecularly-imprinted receptors, identify difficulties in the determinations encountered and highlight proposed solutions to problems. © 2012 Elsevier Ltd.

Uchmanski J.,Cardinal Stefan Wyszynski University in Warsaw
Ecological Modelling | Year: 2016

This paper presents individual-based models describing metapopulation dynamics. The local-population model describes the dynamics of a population without overlapping generations. In each generation, the model follows the individuals' growth. The growth rate of the individuals is affected by the level of resources. The individuals compete for these resources, which are therefore not evenly distributed among them. I compared the persistence of a local population in which the individuals could not disperse with various versions of metapopulation models. Metapopulation models differ in the conditions under which individuals disperse: weaker or stronger competitors, or randomly chosen individuals disperse. Analysis of these models shows that the reasons individuals dispersed affected the persistence of the metapopulation. The influence of the reproduction rate and the individual variability on the persistence of metapopulation is analyzed under the conditions of two types of resource dynamics after the extinction of the local population: with and without regeneration. © 2016 Elsevier B.V..

Opallo M.,Polish Academy of Sciences | Opallo M.,Cardinal Stefan Wyszynski University in Warsaw | Lesniewski A.,Polish Academy of Sciences
Journal of Electroanalytical Chemistry | Year: 2011

Since 2000, ionic liquids are applied for electrode modification. Until the middle of 2010, almost 300 papers about ionic liquid-modified electrodes were published and they are reviewed here. Hydrophobicity, high viscosity, ionic structure, ionic conductivity, very low volatility and biocompatibility are among the properties of ionic liquids making them attractive for electrode modification. From the point of view of their structure, ionic liquid-modified electrodes range from electrode substrates covered by ionic liquid film or droplet(s) to the more complex film consisting of few components including ionic liquid. Bulk-modified electrodes as carbon paste electrodes with ionic liquid as binder and carbon nanotubes - gel electrodes represent another two classes of reviewed electrodes. Electrodes modified with appended ionic liquid form the last group. Initially, research on ionic liquid-modified electrodes was oriented towards fundamental studies of ion transfer across ionic liquid/aqueous solution interface. Now, almost entire research effort in this area is oriented towards their application for electrochemical sensing with multicomponent films and carbon paste electrodes being most popular. © 2011 Elsevier B.V. All rights reserved.

Kieltyk P.,Cardinal Stefan Wyszynski University in Warsaw
Biologia (Poland) | Year: 2014

Bunias orientalis is an alien species that has spread greatly in recent decades in Central Europe. This coloniser is particularly well (pre)adapted to anthropogenic disturbances and human-mediated dispersal, allowing it to spread mainly along roads and railways. Here, its distribution and population structure is investigated for the sub-montane region located in the northern foothills of the Tatra Mts. Based on 70 phytosociological samples of invading vegetation, the relationships between B. orientalis cover and species diversity, together with the composition of vegetation, were analysed using regression analysis. Comparison of the current distribution of B. orientalis within the investigated area with published records indicates that the expansion rate of this alien species is not particularly high, despite its increased frequency in anthropogenic habitats and meadows. Meadows invaded by this species revealed that increased B. orientalis cover was accompanied by a significant reduction in the values of the Inverse Simpson diversity index and Pielou's measure of evenness. Reduced diversity was caused by considerable decrease in cover by species of the Molinio-Arrhenatheretea class. However, for anthropogenic habitats, no statistically significant relationships were found to occur between the abundance of B. orientalis, species diversity and vegetation composition. © 2013 Institute of Botany, Slovak Academy of Sciences.

Radozycki T.,Cardinal Stefan Wyszynski University in Warsaw
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

The Bethe-Salpeter amplitude for the fermion-antifermion bound state in the Schwinger model is investigated. The dependence on the relative time and position in the center-of-mass frame in all contributing instanton sectors is analyzed. The same is accomplished for the relative energy and momentum variables. Several interesting properties of the amplitude are revealed. The explicit threshold structure is demonstrated. © 2013 American Physical Society.

Radozycki T.,Cardinal Stefan Wyszynski University in Warsaw
Acta Physica Polonica B | Year: 2013

Three-dimensional electrodynamics in the spinor (i.e. two-component) version is considered. With the use of the so-called Salam's vertex, the infinite hierarchy of Dyson-Schwinger equations is turned into a set of four self-consistent equations for four parameters describing the infrared behavior of fermion and boson propagators. It is shown numerically, that this set of equations has solutions, at least for certain values of gauge parameter. For weak coupling (i.e. for heavy fermions), the values of all these quantities are found analytically. In the case of massless bare fermion, masses of both particles are generated leading thereby to parity breaking.

Nieznanski M.,Cardinal Stefan Wyszynski University in Warsaw
Quarterly Journal of Experimental Psychology | Year: 2011

The role of the word predictability from sentence context for reality monitoring and external source monitoring was examined in two experiments. In a reality-monitoring task, discrimination of an internal source was better in the hard than in the easy condition. It is probable that extra cognitive operations engaged during word generation in the hard condition were effective cues for reality-monitoring judgements. In contrast, in an external source-monitoring task (recognition memory of item's colour), the hard condition resulted in worse source memory for generated words than did the easy condition. This result is consistent both with an item-context trade-off hypothesis and a processing hypothesis. Greater effort involved at the time of generation might limit resources available for encoding of an external source. It is also possible that for generated words, the hard condition promoted conceptual processing instead of perceptual processing; therefore the item's colour was not effectively encoded. © 2011 The Experimental Psychology Society.

Nieznanski M.,Cardinal Stefan Wyszynski University in Warsaw
Scandinavian Journal of Psychology | Year: 2014

According to many theoretical accounts, reinstating study context at the time of test creates optimal circumstances for item retrieval. The role of context reinstatement was tested in reference to context memory in several experiments. On the encoding phase, participants were presented with words printed in two different font colors (intrinsic context) or two different sides of the computer screen (extrinsic context). At test, the context was reinstated or changed and participants were asked to recognize words and recollect their study context. Moreover, a read-generate manipulation was introduced at encoding and retrieval, which was intended to influence the relative salience of item and context information. The results showed that context reinstatement had no effect on memory for extrinsic context but affected memory for intrinsic context when the item was generated at encoding and read at test. These results supported the hypothesis that context information is reconstructed at retrieval only when context was poorly encoded at study. © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Wolf M.,Cardinal Stefan Wyszynski University in Warsaw
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2014

We give heuristic arguments and computer results to support the hypothesis that, after appropriate rescaling, the statistics of spacings between adjacent prime numbers follows the Poisson distribution. The scaling transformation removes the oscillations in the nearest-neighbor-spacing distribution of primes. These oscillations have the very profound period of length six. We also calculate the spectral rigidity Δ3 for prime numbers by two methods. After suitable averaging one of these methods gives the Poisson dependence Δ3(L)=L/15. © 2014 American Physical Society.

Radozycki T.,Cardinal Stefan Wyszynski University in Warsaw
European Physical Journal C | Year: 2015

The Lorentz transformation properties of the equal-time bound-state Bethe–Salpeter amplitude in the two-dimensional massless quantum electrodynamics (the so-called Schwinger model) are considered. It is shown that while boosting a bound state (a ‘meson’) this amplitude is subject to approximate Lorentz contraction. The effect is exact for large separations of constituent particles (‘quarks’), while for small distances the deviation is more significant. For this phenomenon to appear, the full function, i.e. with the inclusion of all instanton contributions, has to be considered. The amplitude in each separate topological sector does not exhibit such properties. © 2015, The Author(s).

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