Translocation of bacteria from animal excrements to soil and associated habitats

The population dynamics of Salmonella enterica var. Typhimurium MAE 110 gfp, Escherichia coli O157:H7 gfp, and Pseudomonas fluorescens 32 gfp were investigated in their introduction to cattle excrements and subsequent entering the soil, plants of cress (Lepidium sativum L.), and migration through the gastroenteric tract of French snails (Helix pomatia L.). The survival of these bacteria in the excrements and soil was investigated at cyclically changing (day-night, 25–15 °C) and constant (18 °C) temperatures. The cyclically changing temperature adversely affected the survival of E. coli O157:H7 gfp, and P. fluorescens but did not influence S. enterica var. Typhimurium. All the bacteria and, especially, the analogues of enteropathogens showed high survival in the cattle and snail excrements, soil, and on the plants under the gradual decrease in their population. On the cress plants grown in a mixture of cattle excrements and soil, an increase in the number of the introduced bacteria was observe

Daily dynamics of cellulase activity in arable soils depending on management practices

The daily dynamics of cellulase activity was studied during 27 days by the cellophane membrane method on soils managed using the conventional high-input farming system (application of mineral fertilizers and pesticides) and the biological conservation farming system (application of organic fertilizers alone) in a microfield experiment. The regular oscillatory dynamics of the cellulase activity were revealed and confirmed by the harmonic (Fourier) analysis. The oscillatory dynamics of the cellulase activity had a self-oscillatory nature and was not directly caused by the disturbing impacts of both the uncontrolled (natural) changes in the temperature and moisture (rainfall) and the controlled ones (the application of different fertilizers). The disturbing impacts affected the oscillation amplitude of the cellulase activity but not the frequency (periods) of the oscillations. The periodic oscillations of the cellulase activity were more significant in the soil under the high-input management compared to the soil under the biological farming syste

Multistep introduction of bacteria to natural substrates at different initial inoculation doses

The population dynamics of the saprotrophic Pseudomonas fluorescens 32 gfp bacteria and two conventionally pathogenic enterobacteria (Escherichia coli 0157:H7 and Salmonella enterica var. Typhimurium) were investigated in their inoculation at different doses into cattle excreta and their subsequent entering soil and plants and migration through the gastroenteric tract of invertebrates. All the introduced bacteria investigated are shown to be able to overcome ecological barriers as they migrate through the natural substrates and habitats. The introduce microorganisms maintain their high population density even at the lowest initial inoculation dose-10(5) CFU/g of dry matter. Plants were found to be a favorable substrate for the survival of the bacteria investigated (for enteropathogens, in particular). Enteropathogens are able to pass through the gastroenteric tract of invertebrates. Therefore, these organisms can function as incubators and carriers of enteroinfections in natur

The enhancement of ferromagnetism in uniaxially stressed diluted magnetic semiconductors

We predict a new mechanism of enhancement of ferromagnetic phase transition temperature $T_c$ in uniaxially stressed diluted magnetic semiconductors (DMS) of p-type. Our prediction is based on comparative studies of both Heisenberg (inherent to undistorted DMS with cubic lattice) and Ising (which can be applied to strongly enough stressed DMS) models in a random field approximation permitting to take into account the spatial inhomogeneity of spin-spin interaction. Our calculations of phase diagrams show that area of parameters for existence of DMS-ferromagnetism in Ising model is much larger than that in Heisenberg model.Comment: Accepted for publication in Phys. Rev.

Stabilization of elastic inverted pendulum with hysteresis

In this paper, we investigate the elastic inverted pendulum with hysteretic nonlinearity (a back-lash) in the suspension point. Namely, the problems of stabilization and optimization of such a system are considered. The algorithm (based on the bionic model) which provides the effective procedure for finding of optimal parameters is presented and applied to considered system. The results of numerical simulations, namely the phase portraits and the dynamics of Lyapunov function, are also presented and discussed

Шляхи лікарської профілактики та лікування доксорубіцин-індукованої кардіоміопатії в онкологічних хворих

The high incidence of malignant tumors is currently supported by the general ageing of the world population and unfavorable environmental factors. In 2018, 18.1 million new cases of cancer and 9.6 million deaths from them were registered in the world. At the same time, a significant increase in the life expectancy of these patients after the treatment noted over the past 20 years highlights the problem of side effects of the anticancer therapy. One of the most serious side effects is the development of doxorubicin-induced cardiomyopathy (DRIC). In all three distinct clinical forms (acute, early and late) DRIC can develop in 58 % of patients after using anticancer treatment regimens with the inclusion of doxorubicin. The review provides a detailed analysis of medicinal treatment regimens and preparations (ACE inhibitors, beta-blockers, statins, etc.) currently used, and evaluates their effectiveness and expected results. Currently, several therapeutic strategies have been proposed for the prevention and treatment of DRIC, each of them has certain positive results. At the same time, some therapeutic methods used in the clinic have some disadvantages. Conclusions. The limitations of the results of DRIC prevention achieved by the existing therapeutic regimens, as well as the possibilities for their prediction, have been stated. The need for further research to improve the effectiveness of medicinal prevention and treatment of DRIC is emphasized.Высокая заболеваемость злокачественными опухолями в настоящее время объясняется общим старением мирового населения и неблагоприятными факторами экологии. В 2018 году в мире было зарегистрировано 18,1 млн новых случаев онкологических заболеваний и 9,6 млн смертей от них. В то же время отмечаемое за последние 20 лет существенное увеличение продолжительности жизни таких пациентов после лечения выдвигает на первый план проблему побочных эффектов противоопухолевой терапии. Одним из наиболее серьезных является развитие доксорубицин-индуцированной кардиомиопатии (ДРИК). Во всех трех различаемых клинических формах (острой, ранней и поздней) ДРИК может развиться у 58 % пациентов после использования схем противоопухолевого лечения с включением доксорубицина. В обзоре детально проанализированы используемые в настоящее время схемы лекарственного лечения и препараты (ингибиторы АПФ, бета-адреноблокаторы, статины и др.), оценена их эффективность и ожидаемый результат. В настоящее время предложено несколько терапевтических стратегий по профилактике и лечению ДРИК, каждая из которых дает определенные положительные результаты. В то же время некоторые используемые в клинике терапевтические методы обладают и целым рядом недостатков. Выводы. Констатирована ограниченность достигаемых результатов профилактики ДРИК существующими терапевтическими схемами, а также возможностей для их индивидуального прогнозирования. Подчеркивается необходимость дальнейших исследований с целью повышения эффективности лекарственной профилактики и лечения ДРИК.Висока захворюваність на злоякісні пухлини на теперішній час підтримується загальним старінням населення світу і несприятливими факторами екології. У 2018 році в світі було зареєстровано 18,1 млн нових випадків онкологічних захворювань і 9,6 млн смертей від них. У той же час за останні 20 років відзначається істотне збільшення тривалості життя таких пацієнтів після лікування, що висуває на перший план проблему побічних ефектів протипухлинної терапії. Одним з найбільш серйозних з них є розвиток доксорубіцин-індукованої кардіоміопатії (ДРІК). У всіх трьох клінічних формах (гострій, ранній та пізній) ДРІК спроможна розвинутися у 58 % пацієнтів після використання схем протипухлинного лікування з включенням доксорубіцину. В огляді детально проаналізовані схеми лікарського лікування і препарати (інгібітори АПФ, бета-адреноблокатори, статини та ін.), що використовуються в теперішній час, оцінена їх ефективність і очікуваний результат. Натепер запропоновано декілька терапевтичних стратегій з профілактики та лікування ДРІК, кожна з яких має визначені позитивні результати. У той же час деякі використовувані в клініці терапевтичні методи мають і цілий ряд недоліків. Висновки. Констатовано обмеженість досяжних результатів профілактики ДРІК існуючими терапевтичними схемами, а також можливостей для їх індивідуального прогнозування. Підкреслюється необхідність подальших досліджень з метою підвищення ефективності лікарської профілактики і лікування ДРІК

Suppression of carrier induced ferromagnetism by composition and spin fluctuations in diluted magnetic semiconductors

We suggest an approach to account for spatial (composition) and thermal fluctuations in "disordered" magnetic models (e.g. Heisenberg, Ising) with given spatial dependence of magnetic spin-spin interaction. Our approach is based on introduction of fluctuating molecular field (rather than mean field) acting between the spins. The distribution function of the above field is derived self-consistently. In general case this function is not Gaussian, latter asymptotics occurs only at sufficiently large spins (magnetic ions) concentrations $n_i$. Our approach permits to derive the equation for a critical temperature $T_c$ of ferromagnetic phase transition with respect to the above fluctuations. We apply our theory to the analysis of influence of composition fluctuations on $T_c$ in diluted magnetic semiconductors (DMS) with RKKY indirect spin-spin interaction.Comment: 6 pages, 2 figure

Validity of the scaling functional approach for polymer interfaces as a variational theory

We discuss the soundness of the scaling functional (SF) approach proposed by Aubouy Guiselin and Raphael (Macromolecules 29, 7261 (1996)) to describe polymeric interfaces. In particular, we demonstrate that this approach is a variational theory. We emphasis the role of SF theory as an important link between ground-state theories suitable to describe adsorbed layers, and "classical" theories for polymer brushes.Comment: 8 pages, 1 figure, to be published in Phys. Rev.

Unbounded solutions for systems with hysteretic nonlinearity

The work is dedicated to study of the dynamics of model systems that are described by differential equations with additive hysteretic nonlinearities in the case when a hysteretic loop bypass clockwise. In particular, for the model of the harmonic oscillator with hysteretic external force the conditions for existence of unbounded solutions are obtained. For the model of harmonic oscillator with a dry (Coulomb) and viscous friction under external hysteretic affection we obtained a set of conditions that ensure the self-oscillation mode. The numerical examples that illustrate the results of this work are also presented.This work is supported by the RFBR grant No 16-08-00312, 17-01-00251

Hysteretic damper based on Bouc-Wen model

In the presented work we consider the dynamics of the mechanical system under internal force with a damper taking into account the hysteretic nature of the damper. As a mathematical model of this hysteretic damper we consider the Bouc-Wen model. The obtained numerical results in the form of the force transfer function demonstrates the efficiency of the hysteretic damper in comparison with the nonlinear viscous damper.This work is supported by the RFBR grant No 16-08-00312, 17-01-00251