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The phase-space approach based on the Wigner distribution function is used to study the quantum dynamics of the three families of the Schrödinger cat states identified as the even, odd, and Yurke-Stoler states. The considered states are formed by the superposition of two Gaussian wave packets localized on opposite sides of a smooth barrier in a dispersive medium and moving towards each other. The process generated by this dynamics is analyzed regarding the influence of the barrier parameters on the nonclassical properties of these states in the phase space below and above the barrier regime. The performed analysis employs entropic measure resulting from the Wigner-Rényi entropy for the fixed Rényi index. The universal relation of this entropy for the Rényi index equal one half with the nonclassicality parameter understood as a measure of the negative part of the Wigner distribution function is proved. This relation is confirmed in the series of numerical simulations for the considered states. Furthermore, the obtained results allowed the determination of the lower bound of the Wigner-Rényi entropy for the Rényi index greater than or equal to one half.

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Magnetotransport properties of a semiconductor nanowire with a constriction have been studied within the Landauer-Büttiker formalism in the presence of the axially oriented magnetic field at low temperatures. The one-electron quantum states in the nanowire have been calculated within the adiabatic approximation which takes into account the three-dimensional structure of the nanowire and allows us to study the effect of the transverse quantum states on the electronic current. The calculated current-voltage characteristics exhibit well pronounced peaks that result from the enhancement of the electron transmission by the Stark resonant states formed in the triangular quantum well near the constriction. The effect of the Stark resonances is clearly manifested in the magnetoresistance as a function of the drain-source voltage. The calculated magnetoresistance exhibits two interesting features: (i) rapid jumps at certain voltages, caused by the enhancement of the electron transmission by the Stark resonances, (ii) changes of sign that stem from the magnetic-field induced changes of the current-voltage characteristics slope. The influence of the constriction parameters (radius, length, smoothness of the potential barrier, position of the constriction in the nanowire) on the electronic current has also been analyzed. Since the effective potential barrier created by the constriction in the nanowire is similar to that generated by the negatively charged gate surrounding the nanowire, the presented results can also be applied to the description of the magnetoresistance in the gated nanowires.

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OBJECTIVE: Chronic pain is an important part of the clinical picture in patients with RA and therefore the authors attempted to assess the relationship of pain of patients with RA to the inflammatory process, articular damage and to predict the variance of pain in relation to psychosocial, demographic factors and functional disability. METHOD: Pain was examined using the Nottingham Health Profile (NHP), psychological health by means of the General Health Questionnaire (GHQ) and disability was assessed by the Health Assessment Questionnaire (HAQ). RESULTS: The authors examined 160 patients with RA with a mean age of 48.34 +/- 12.13 years and persistence of the disease for 21.32 +/- 15.61 months. Pain was significantly related to clinical manifestations of inflammation and articular damage. The relationship between pain and laboratory manifestations of inflammation (CRP, FW) was not very close. The relationship between age and pain and between persistence of the disease and pain was not statistically significant. Pain correlated significantly with functional disability (HAQ) (r = -0.54) and the articular index (RAI) (r = 0.58). Pain did not correlate with manifestations of depression (r = -0.15), but correlated significantly with anxiety (r = -0.35) and social dysfunction (r = -0.36). Among the investigated parameters (demographic factors, GHQ and HAQ) the most marked variation of pain was caused by HAQ (32%), GHQ (8%). Almost unrelated were demographic parameters (0.6%) (age, persistence of disease, education lifestyle, and gender).

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The authors discuss intermittent transcutaneous monitoring of the acid base balance in blood where the feedback model: lungs-milieou intérieur is used as part of a new theory, i.e. the concept of "electronic blood" (Kovác A.) which implies simulation of the internal environment by a computer. Part of the model, evidence of the existing relationship of the external and internal environment are the following parameters: a shift in the Haldane effect and the constant in Haldane's effect. The authors compare the values of the acid-base balance obtained by surgical means and by means of a computer.

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The authors examined anamnestically, by interdermal tests with tobacco extract, by assessment of serum IgE and thiocyanates in saliva (according to David and Densen) 234 children with allergic diseases (rhinitis pollinosa, asthma bronchiale, dermorespiratory syndrome). They revealed a high ratio of positive tests in passive smokers (71.8% of the tested children), as compared with children not exposed to smoking (16.1% of the tested children). With advancing age of the probands the ratio of positive tests increased. The authors observed a significant difference in IgE concentrations in passive smokers of all age groups of children with the exception of those aged 1 to 3 years as compared with those not exposed to tobacco smoke. They found also significant differences in the thiocyanates concentrations in saliva between exposed and non-exposed children (223 and 126.4 mumol/l resp.). With regard to the above facts it is important to prevent exposure of predisposed as well as healthy children to cigarette smoke.

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