Особенности рекреационного потенциала лесных биогеоценозов Клинско-Дмитровской гряды

The article is devoted to recreational opportunities of forest ecosystems of Clinsko-Dmytrovskaja Grjada. Recreational potential in connection of forest types was given as result of male study. As a result of studies is assessed the recreational potential in relation to forest types. The impact of various forms of rechation on the state of the main elements of the forest has been given. The description of flora and fauna have been given.Статья посвящена выявлению рекреационных возможностей лесных биогеоценозов Клинско-Дмитровской гряды. В результате проведенных исследований была дана оценка рекреационного потенциала в связи с типами леса. Выявлено воздействие различных форм рекреации на состояние основных элементов леса. Приведено описание флоры и фауны объекта исследования

Благоустройство и озеленение объектов ландшафтной архитектуры с учетом экотуризма

The presented paper is devoted to problem of recreation. Ecotourism is typical for many countries. The paper selects the latest projects of ecoparks around the world, and very interesting it is proposed and described at the Yaroslavl region. (Also the paper selects the latest projects of ecoparks around the world) Provides information of the functional zoning of the territory. Proposed landscape, recreation and hydro activities will improve the attractiveness of the area and at the same time improve its stability. The paper would be a valuable resource and reference for landscape designers, architects, students.Представленная статья посвящена проблеме организации отдыха. Экотуризм характерен для многих стран. В данной статье он рассмотрен на интересном примере Ярославской области. Представлена информация по функциональному зонированию территории. Предложенные мероприятия - ландшафтные, рекреационные, гидротехнические - позволят улучшить привлекательность участка и в то же время повысить его устойчивость

On a possibility of the blocking of DNA specific recognition sites by hydrogen peroxide molecules during ion beam therapy

Ion beam therapy is one of the most effective methods in treatment of cancer diseases. But up to nowadays, the mechanism of action of heavy ions on cancer cells has not been determined yet. Study of water fragmentation processes during ion beam therapy shows that, among different oxygen species, the significant amount of hydrogen peroxide molecules (H₂O₂) occurs in the сell medium. In the present work, the competitive interaction of H₂O₂ and H₂O molecules with specific DNA recognition sites is studied. Interaction energies of complexes consisting of nucleic bases (adenine, thymine, guanine, and cytosine) together with hydrogen peroxide and water molecules are calculated, using the method of atom-atom potential functions and density functional theory. The atomic groups of nuc leic bases that are more energetically favorable to be bound by hydrogen peroxide rather than by water molecule are found. Formation of such complexes can block the process of DNA replication on different stages and can be one of the mechanisms of ion beam action on cancer cells.Іонна терапія є одним з найефективніших методів лікування ракових захворювань. Але до цього часу механізм дії важких іонів на ракові клітини не визначений. Вивчення процесів фрагментації води під час іонної терапії показує, що серед великої кількості різних фрагментів у середовищі клітини утворюється значна концентрація молекул пероксиду водню (H₂O₂). У роботі наведено результати дослідження конкурентної взаємодії молекул H₂O₂ та H₂O із центрами специфічного розпізнавання ДНК. Енергії взаємодії комплексів, що складаються з нуклеїнових основ (аденін, тимін, гуанін і цитозин) разом з молекулами пероксиду водню і води, обчислені із застосуванням методу атом-атомних потенціальних функцій і теорії функціонала густини. Знайдено атомні групи нуклеїнових основ, які є більш енергетично вигідними для зв’язування з молекулами пероксиду водню, ніж з молекулами води. Утворення таких комплексів може блокувати процес реплікації ДНК на різних етапах і може бути одним з механізмів дії високоенергетичних іонів на ракові клітини.Ионная терапия является одним из наиболее эффективных методов лечения раковых заболеваний. Но до настоящего времени механизм действия тяжелых ионов на раковые клетки не установлен. Изучение процессов фрагментации воды при ионной терапии показывает, что среди большого количества различных фрагментов в клеточной среде образуется значительная концентрация молекул пероксида водорода (H₂O₂). В работе приведены результаты изучения конкурентного взаимодействия молекул H₂O₂ и H₂O с центрами специфического узнавания ДНК. Энергии взаимодействия комплексов, состоящих из нуклеиновых оснований (аденин, тимин, гуанин и цитозин) вместе с молекулами пероксида водорода и воды, рассчитаны с использованием метода атом-атомных потенциальных функций и теории функционала плотности. Найдены атомные группы нуклеиновых оснований, с которыми молекула пероксида водорода связывается значительно энергетически выгоднее, чем молекула воды. Образование таких комплексов может блокировать процесс репликации ДНК на разных стадиях и может быть одним из механизмов воздействия высокоэнергетических ионов на раковые клетки

Stability of Driven Josephson Vortex Lattice in Layered Superconductors Revisited

We analytically study stability of sliding lattice of Josephson vortices driven by a transport current in the stack direction in strong in-plane magnetic field. In contrast to recent findings we obtain that there are no diverse configurations of stable vortex lattices, and, hence, the stable sliding vortex lattice can not be selected by boundary conditions. We find that only the triangular (rhombic) lattice can be stable, its stability being limited by a critical velocity value. At higher velocities there are no simple stable lattices with single flux line per unit cell. Oblique sliding lattices are found to be never stable. Instability of such lattices is revealed beyond the linear approximation in perturbations of the lattice.Comment: 11 pages, 2 figures, RevTeX 4, Submitted to Phys. Rev.

Nonequilibrium Josephson effect in short-arm diffusive SNS interferometers

We study non-equilibrium Josephson effect and phase-dependent conductance in three-terminal diffusive interferometers with short arms. We consider strong proximity effect and investigate an interplay of dissipative and Josephson currents co-existing within the same proximity region. In junctions with transparent interfaces, the suppression of the Josephson current appears at rather large voltage, $eV\sim \Delta$, and the current vanishes at $eV\geq\Delta$. Josephson current inversion becomes possible in junctions with resistive interfaces, where the inversion occurs within a finite interval of the applied voltage. Due to the presence of considerably large and phase-dependent injection current, the critical current measured in a current biased junction does not coincide with the maximum Josephson current, and remains finite when the true Josephson current is suppressed. The voltage dependence of the conductance shows two pronounced peaks, at the bulk gap energy, and at the proximity gap energy; the phase oscillation of the conductance exhibits qualitatively different form at small voltage $eV<\Delta$, and at large voltage $eV>\Delta$.Comment: 11 pages, 9 figures, revised version, to be published in Phys. Rev.

Coherent Charge Transport in Metallic Proximity Structures

We develop a detailed microscopic analysis of electron transport in normal diffusive conductors in the presence of proximity induced superconducting correlation. We calculated the linear conductance of the system, the profile of the electric field and the densities of states. In the case of transparent metallic boundaries the temperature dependent conductance has a non-monotoneous ``reentrant'' structure. We argue that this behavior is due to nonequilibrium effects occuring in the normal metal in the presence of both superconducting correlations and the electric field there. Low transparent tunnel barriers suppress the nonequilibrium effects and destroy the reentrant behavior of the conductance. If the wire contains a loop, the conductance shows Aharonov-Bohm oscillations with the period $\Phi_0=h/2e$ as a function of the magnetic flux $\Phi$ inside the loop. The amplitude of these oscillations also demonstrates the reentrant behavior vanishing at $T=0$ and decaying as $1/T$ at relatively large temperatures. The latter behavior is due to low energy correlated electrons which penetrate deep into the normal metal and ``feel'' the effect of the magnetic flux $\Phi$. We point out that the density of states and thus the ``strengh'' of the proximity effect can be tuned by the value of the flux inside the loop. Our results are fully consistent with recent experimental findings.Comment: 16 pages RevTeX, 23 Postscript figures, submitted to Phys. Rev.

Quantum Inequalities for the Electromagnetic Field

A quantum inequality for the quantized electromagnetic field is developed for observers in static curved spacetimes. The quantum inequality derived is a generalized expression given by a mode function expansion of the four-vector potential, and the sampling function used to weight the energy integrals is left arbitrary up to the constraints that it be a positive, continuous function of unit area and that it decays at infinity. Examples of the quantum inequality are developed for Minkowski spacetime, Rindler spacetime and the Einstein closed universe.Comment: 19 pages, 1 table and 1 figure. RevTex styl

Superconductive proximity effect in interacting disordered conductors

We present a general theory of the superconductive proximity effect in disordered normal--superconducting (N-S) structures, based on the recently developed Keldysh action approach. In the case of the absence of interaction in the normal conductor we reproduce known results for the Andreev conductance G_A at arbitrary relation between the interface resistance R_T and the diffusive resistance R_D. In two-dimensional N-S systems, electron-electron interaction in the Cooper channel of normal conductor is shown to strongly affect the value of G_A as well as its dependence on temperature, voltage and magnetic field. In particular, an unusual maximum of G_A as a function of temperature and/or magnetic field is predicted for some range of parameters R_D and R_T. The Keldysh action approach makes it possible to calculate the full statistics of charge transfer in such structures. As an application of this method, we calculate the noise power of an N-S contact as a function of voltage, temperature, magnetic field and frequency for arbitrary Cooper repulsion in the normal metal and arbitrary values of the ratio R_D/R_T.Comment: RevTeX, 28 pages, 18 PostScript figures; added and updated reference

On the nonlinear dynamics of topological solitons in DNA

Dynamics of topological solitons describing open states in the DNA double helix are studied in the frameworks of the model which takes into account asymmetry of the helix. It is shown that three types of topological solitons can occur in the DNA double chain. Interaction between the solitons, their interactions with the chain inhomogeneities and stability of the solitons with respect to thermal oscillations are investigated.Comment: 16 pages, 16 figure