Dynamics of some piecewise smooth Fermi-Ulam Models

We find a normal form which describes the high energy dynamics of a class of piecewise smooth Fermi-Ulam ping pong models; depending on the value of a single real parameter, the dynamics can be either hyperbolic or elliptic. In the first case we prove that the set of orbits undergoing Fermi acceleration has zero measure but full Hausdorff dimension. We also show that for almost every orbit the energy eventually falls below a fixed threshold. In the second case we prove that, generically, we have stable periodic orbits for arbitrarily high energies, and that the set of Fermi accelerating orbits may have infinite measure.Comment: 22 pages, 4 figure

ESTIMATION METHOD FOR MULTIPAHT CHANNELS OF HIGH-SPEED DATA TRANSMISSION SYSTEMS WITH OFDM BASED ON REGRESSION ANALYSIS

This text describes a technique for estimating a multipath radio channel of high-speed data transmission systems with OFDM modulation based on regression analysis. A brief de-scription of the proposed technique and its effectiveness is given

Combination therapy for benign prostate hyperplasia-related urinary symptoms

Introduction. Non-neurogenic lower urinary tract symptoms (LUTS) are a serious polyetiologic problem in the male population. The side effects of the medication agents used to treat LUTS significantly reduce treatment compliance. According to the literature data, the frequency of refusal for the proposed treatment during the year varies from 20 to 80%. Several studies have shown the benefits of herbal medicine for LUTS concerning the fewer side effects and increased adherence to treatment. However, to obtain a high-level recommendation base, clinical trials are required.Purpose of the study. To evaluate the effectiveness of Gardaprost® in LUTS combination therapy.Materials and methods. The study included 57 men aged 60 – 70 years with diagnosed medium- or large-volume benign prostatic hyperplasia (BPH) and moderate-to-severe LUTS according to I-PSS, morphologically excluded prostate cancer, without urinary infection signs. The patients were randomized into two follow-up groups. Tamsulosin 0.4 mg q.d. was prescribed to patients in the control group. Patients of the main group received Gardaprost® 0.4 mg q.d. in addition to Tamsulosin. The follow-up period in both groups was one-year. The statistical analysis includes data from 56 men. To evaluate therapy at the screening visit and on days 180 and 360, I-PSS, urination diary, IIEF-5, urinalysis, prostate-specific antigen, uroflowmetry, ultrasound were analyzed. Paired t-test and one-way ANOVA test were used to determine intergroup differences in normally distributed variables. For variables with a distribution other than normal, Friedman's two-way ANOVA for related samples was used. Events with a probability greater than 95% were considered statistically significant.Results. At the time of inclusion in the study, the groups were comparable concerning the control parameters. In the main group, there was a more pronounced positive dynamics in the I-PSS score, maximum urine flow rate, and post-void residual urine volume, which corresponded to 7.9 ± 2.1 points, 18.0 ± 7.3 ml/sec, 23.6 ± 13.6 ml vs 19.7 ± 7.2 points, 10 ± 3.5 ml/sec, 65.9 ± 33.2 ml in the main and control groups, respectively (p < 0.001). Additionally, in the main observation group, a decrease in prostate volume was recorded by 18.8% (p < 0.001) was recorded.Conclusion. We have obtained encouraging long-term results from the use of Gardaprost® in combination therapy of moderate-to-severe LUTS caused by medium- and large-volume BPH

Treatment of overactive bladder symptoms in women with Diunorm®: preliminary results report

Introduction. Overactive bladder (OAB) with or without urgent incontinence tends to progress with age and occurs in both men and women. However, the frequency of occurrence in the female population averages about 25%.Purpose of the study. To assess the effectiveness and safety of the drug Diunorm® (in caps.) in the prevention and treatment of OAB in women.Materials and methods. The statistical analysis includes the results of a survey of 28 women with symptoms of OAB, whose average age was 35.3 years. The drug Diunorm® was used for treatment in dosage 400 mg QD for 90 days. Patients completed the Overactive Bladder Awareness Tool and a urination diary. Additionally, urinalysis, bacteriological examination of urine, uroflowmetry, bladder ultrasound and cystoscopy were performed.Results. All women throughout the study had negative urine cultures and no pyuria in urinalysis, which excluded an infectious etiology of urinary dysfunction. During therapy, a statistically significant decrease in irritative symptoms was recorded according to the Overactive Bladder Awareness Tool questionnaire. The sum of points after 1 and 3 mo decreased by 3.0 and 4.3 points, respectively (p < 0.05). Positive dynamics in terms of the points' sum was noted in 75%, in relation to nocturia in 82% of patients (p < 0.01). The average urination rate increased from 13.3 ± 0.7 ml/s to 15.1 ± 0.7 ml/s and 15.4 ± 0.5 ml/s after 1.5 and 3 months, respectively (p < 0,0001). A similar trend was observed for maximum urine flow and residual urine volume. The maximum urine flow when taking Diunorm® increased from 15.9 ± 0.6 ml/s to 17.4 ± 0.5 ml/s and 18.1 ± 0.4 ml/s (p < 0.001). Residual urine volume decreased throughout the study. When included in the study, after 1,5 and 3 mo, this indicator was 19.9 ± 1.4; 12.2 ± 1.6 and 6.4 ± 1.1 ml, respectively (p < 0.001).Conclusion. Diunorm® can become a worthy alternative to traditional first-line OAB therapy. Comparative studies are required to obtain a high-level evidence base

Chaos, Fractals and Inflation

In order to draw out the essential behavior of the universe, investigations of early universe cosmology often reduce the complex system to a simple integrable system. Inflationary models are of this kind as they focus on simple scalar field scenarios with correspondingly simple dynamics. However, we can be assured that the universe is crowded with many interacting fields of which the inflaton is but one. As we describe, the nonlinear nature of these interactions can result in a complex, chaotic evolution of the universe. Here we illustrate how chaotic effects can arise even in basic models such as homogeneous, isotropic universes with two scalar fields. We find inflating universes which act as attractors in the space of initial conditions. These universes display chaotic transients in their early evolution. The chaotic character is reflected by the fractal border to the basin of attraction. The broader implications are likely to be felt in the process of reheating as well as in the nature of the cosmic background radiation.Comment: 16 pages, RevTeX. See published version for fig