Young's modulus of polyelectrolyte multilayers from microcapsule swelling

We measure Young's modulus of a free polyelectrolyte multilayer film by studying osmotically induced swelling of polyelectrolyte multilayer microcapsules filled with the polyelectrolyte solution. Different filling techniques and core templates were used for the capsule preparation. Varying the concentration of the polyelectrolyte inside the capsule, its radius and the shell thickness yielded an estimate of an upper limit for Young's modulus of the order of 100 MPa. This corresponds to an elastomer and reflects strong interactions between polyanions and polycations in the multilayer

Role of Russia in peaceful settlement of the conflict of North and South Korea: event analysis

This study analyzes the conflict between North Korea and South Korea. The Russian Federation has played an important role in the peaceful settlement of this conflict, which has an impact on the formation of the appearance of Russia in the international arena. The theoretical basis of the study was the theory of images, communication and international conflicts. Using the eventanalysis method, an event-based picture of the conflict was built, comparative assessments were made, conflicting parties, indirect participants and intermediaries were identified. An analysis of the current situation is given, groups of interests and the role of Russia in the peaceful settlement of this conflict are identified.Este estudio analiza el conflicto entre Corea del Norte y Corea del Sur. La Federación de Rusia ha desempeñado un papel importante en la solución pacífica de este conflicto, que tiene un impacto en la formación de la aparición de Rusia en la arena internacional. La base teórica del estudio fue la teoría de las imágenes, la comunicación y los conflictos internacionales. Utilizando el método de análisis de eventos, se construyó una imagen del conflicto basada en eventos, se realizaron evaluaciones comparativas, se identificaron las partes en conflicto, los participantes indirectos y los intermediarios. Se presenta un análisis de la situación actual, se identifican los grupos de intereses y el papel de Rusia en la solución pacífica de este conflicto.Este estudo analisa o conflito entre a Coréia do Norte e a Coréia do Sul. A Federação Russa tem desempenhado um papel importante na solução pacífica deste conflito, que tem um impacto sobre a formação da aparição da Rússia na arena internacional. A base teórica do estudo foi a teoria das imagens, comunicação e conflitos internacionais. Usando o método de análise de eventos, uma imagem baseada em eventos do conflito foi construída, avaliações comparativas foram feitas, partes conflitantes, participantes indiretos e intermediários foram identificados. Uma análise da situação atual é dada, grupos de interesses e o papel da Rússia na solução pacífica deste conflito são identificados

Dynamics of Switching Waves in a Nanofluid in a Light Field

The dynamics of the concentration of nanofluids placed in a light field with a Gaussian intensity profile is studied theoretically. The investigation is based on the analytical and numerical solutions of the system of linearized heat conduction and convectiondiffusion equations. The convection-diffusion equation contains terms that correspond both to the Soret effect and to the transfer of nanoparticles, caused by the action of a light field on them (electrostriction). The dependence of the coefficient of thermal conductivity of the medium on the concentration is taken into account. It is shown that under these conditions single travelling waves appear in the medium, the velocity of which depends not only on the thermal physical parameters of the medium, but also on the polarization of the particles. Conditions under which the stratification of the medium is possible are found

Nonlinear acoustic waves in channels with variable cross sections

The point symmetry group is studied for the generalized Webster-type equation describing non-linear acoustic waves in lossy channels with variable cross sections. It is shown that, for certain types of cross section profiles, the admitted symmetry group is extended and the invariant solutions corresponding to these profiles are obtained. Approximate analytic solutions to the generalized Webster equation are derived for channels with smoothly varying cross sections and arbitrary initial conditions.Comment: Revtex4, 10 pages, 2 figure. This is an enlarged contribution to Acoustical Physics, 2012, v.58, No.3, p.269-276 with modest stylistic corrections introduced mainly in the Introduction and References. Several typos were also correcte

Optical echo in photonic crystals

The dynamics of photonic wavepacket in the effective oscillator potential is studied. The oscillator potential is constructed on a base of one dimensional photonic crystal with a period of unit cell adiabatically varied in space. The structure has a locally equidistant discrete spectrum. This leads to an echo effect, i.e. the periodical reconstruction of the packet shape. The effect can be observed in a nonlinear response of the system. Numerical estimations for porous-silicon based structures are presented for femtosecond Ti:Sapphire laser pump.Comment: 4 page

Quaternionic factorization of the Schroedinger operator and its applications to some first order systems of mathematical physics

We consider the following first order systems of mathematical physics. 1.The Dirac equation with scalar potential. 2.The Dirac equation with electric potential. 3.The Dirac equation with pseudoscalar potential. 4.The system describing non-linear force free magnetic fields or Beltrami fields with nonconstant proportionality factor. 5.The Maxwell equations for slowly changing media. 6.The static Maxwell system. We show that all this variety of first order systems reduces to a single quaternionic equation the analysis of which in its turn reduces to the solution of a Schroedinger equation with biquaternionic potential. In some important situations the biquaternionic potential can be diagonalized and converted into scalar potentials

Interannual variability of the Black Sea Proper oxygen and nutrients regime: The role of climatic and anthropogenic forcing

The Black Sea is a unique, stratified, enclosed ocean basin of great importance. The water column provides a wealth of information concerning aerobic-anaerobic biogeochemistry, the responses of which can have links to anthropogenic and climatic forcing. Herein, we synthesize dissolved oxygen (DO) and nutrient data (phosphate, dissolved inorganic nitrogen (DIN), and silicate) for the period 1984-2010 received in the northeastern and western areas of the Sea. In the subsequent analysis we discuss the role of anthropogenic and climatic forcing in the context of the Black Sea oxic layer and oxic/anoxic interface characteristics.The DO concentration in the surface layer and in the Cold Intermediate Layer (CIL) decreased in warm periods and increased in cold periods, correlating to North Atlantic Oscillation (NAO) index variation. The biogeochemical regime of the Black Sea oxygenated upper layer has notably changed since 1999. After 1999 DO concentration in the CIL decreased by 20% while the concentrations in the surface layer changed very little. This provides evidence that the CIL waters were not fully replenished during the winters of the last decade.The nutrient concentrations (DIN and phosphate) in the surface layer decreased significantly in the 2000s compared with the 1980s-1990s. This decrease is regarded as improvement of the Black Sea ecosystem state. Oxygen and nutrient dynamics in the middle pycnocline have been decoupled since 1999. Presently physical (climatic) forcing is the dominant affecting factor controlling the Sea oxygen and nitrogen regime. © 2013 Elsevier Ltd

The problem of quality assessing for the methods of coherence maps calculation in InSAR remote sensing of the Earth data processing

Interferometric coherence is an important indicator of the quality of interferograms obtained by synthetic aperture interferometric radars (InSAR), because the areas with low coherence are not suitable for interferometric data processing. The coherence value is used as a parameter for adaptive phase noise suppression algorithms. It can also be used for surface classification tasks. The paper investigates the problem of the coherence estimate reducing under the influence of the topographic phase slope and considers ways to reduce the impact of the slope on the estimate value. The paper presents a comparative efficiency analysis of four methods for coherence maps calculation used for the phase noise suppression on the interferograms by a spectral adaptive filter in interferometric data processing for the Earth's remote sensing space radar ALOS PALSAR. © Published under licence by IOP Publishing Ltd

Effect of Drying Mode of Bacterial Biomass on the Effectiveness of Extraction and Physicochemical Properties of the Product (Polymer)

Проведено сравнительное исследование различных режимов высушивания биомассы бактерий Cupriavidus eutrophus В10646. Показано, что различные режимы оказывают влияние на выход конечного продукта (полимера) и его физико-химические свойства (молекулярно-массовые и температурные характеристики). Использование высоких температур приводит к деградации полимера и снижению его молекулярной массы. Применение сублимационной сушки позволяет получить рыхлую биомассу с довольно развитой поверхностью, что благоприятно сказывается на процессе экстракции и не приводит к изменению молекулярно-массовых характеристик полимераComparative study of different drying modes of bacterial biomass of Cupriavidus eutrophus В10646 was conducted. Different modes differently affect the yield of the product (polymer) and its physicochemical properties (molecular weight distribution and temperature characteristics). High temperatures caused the polymer degradation and decrease of its molecular weight. Using freeze drying allows to obtain friable biomass with an extended surface which is favorable for extraction process and to preserve the molecular weight characteristics of the polyme

The haunted delimitation of subjectivity in the Work of Nicolas Abraham

Kinesin-like calmodulin binding protein (KCBP), a Kinesin-14 family motor protein, is involved in the structural organization of microtubules during mitosis and trichome morphogenesis in plants. The molecular mechanism of microtubule bundling by KCBP remains unknown. KCBP binding to microtubules is regulated by Ca(2+)-binding proteins that recognize its C-terminal regulatory domain. In this work, we have discovered a new function of the regulatory domain. We present a crystal structure of an Arabidopsis KCBP fragment showing that the C-terminal regulatory domain forms a dimerization interface for KCBP. This dimerization site is distinct from the dimerization interface within the N-terminal domain. Side chains of hydrophobic residues of the calmodulin binding helix of the regulatory domain form the C-terminal dimerization interface. Biochemical experiments show that another segment of the regulatory domain located beyond the dimerization interface, its negatively charged coil, is unexpectedly and absolutely required to stabilize the dimers. The strong microtubule bundling properties of KCBP are unaffected by deletion of the C-terminal regulatory domain. The slow minus-end directed motility of KCBP is also unchanged in vitro. Although the C-terminal domain is not essential for microtubule bundling, we suggest that KCBP may use its two independent dimerization interfaces to support different types of bundled microtubule structures in cells. Two distinct dimerization sites may provide a mechanism for microtubule rearrangement in response to Ca(2+) signaling since Ca(2+)- binding proteins can disengage KCBP dimers dependent on its C-terminal dimerization interface