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Optical methods are widely used to perform fundamental studies of living systems and solve problems of biomedical diagnostics. Along with the classical spectroscopy, methods of nonlinear optics (e.g., multiphoton microscopy) are also applied in biophotonics. The potential of nonlinear optical methods for visualisation and analysis of the properties of endogenous chromophore molecules are considered in this minireview. Melanin – a pigment with specific spectral features of photophysical properties in the visible and near-IR ranges – is taken as an example. It is discussed what information about its localisation in tissues and structural organisation can be obtained by nonlinear optical methods: multiphoton fluorescence microscopy (including fluorescence lifetime imaging), third harmonic generation, pump – probe spectroscopy, and coherent anti-Stokes Raman spectroscopy.

The issues of developing a methodology for calculating the specific rates of electrical energy consumption during frequency regulation of electric drives of pumping stations are considered. When calculating specific consumption rates, experimental studies were carried out at the Chirchik pumping station. When developing the methodology, technological, design parameters, water consumption, as well as the total capacity of pumping units based on frequency-controlled electric drives are taken into account. At the same time, the characteristics of the main parameters that must be taken into account when choosing variable frequency drives for pumping units are determined.

The work focuses on the study of the charge relaxation kinetics in composite materials based on polyethylene. Time dependences of the electretic potential differences for samples with different mass values of the filler, as well as dependences of conductivity from the mass percentage of the filler, were achieved. The conductivity curves were analyzed according to the modern theory of intrinsic conductivity.

In this work, the surface of polyimide films of PMDA-ODA was modified using a barrier discharge in order to optimize their biological properties when interacting with a culture of human dermal fibroblasts. The optimal modes of processing films in a gas discharge, which allows to increase the proliferative activity of cells, are found.

The semiclassical approximation of quantum computing and quasi-qubits (s-bits) have been obtained by us as a result of our work over the past few years. This work can be conventionally divided into two parts. The first part, let’s call it the programming model, contains a computer model of quasi-qubits and quantum computing. The second part, let’s call it the microelectronic model, describes the microelectronic realization of qubits in the semiclassical approximation (quasi-qubits) and exists in the form of block diagrams, which are supposed to be easy to manufacture. How did we get the semiclassical approximation? The difficulty in solving such a problem was that microparticles in quantum mechanics are described in an infinite-dimensional Hilbert space. Classical models are much poorer in the number of variables; therefore, it is impossible to describe quantum mechanical objects by classical methods due to the small number of available parameters.

A new eavesdropping strategy is proposed for the Quantum Key Distribution (QKD) protocol. This scheme represents a new kind of intercept/resend strategy based on Bell’s theorem. Quantum key distribution (QKD) provides the foremost reliable form of secure key exchange, using only the input-output statistics of the devices to realize information-theoretic security. In this paper, we present an improved QKD protocol that can simultaneously distribute the quantum secret key. We are already using the QKD protocol with simulated results matched completely with the theoretical concepts.

In cases where physical processes cannot be described by linear equations, and nonlinear equations are difficult to solve mathematically, we have to use approximate solutions to such problems. One such example is the description of the Kapitsa pendulum, which is a pendulum with a vibrating suspension point. In contrast to the previously known methods of describing such a problem, in this paper we propose to use additional variables in the form of higher derivatives, which allows us to obtain corrections that give a more detailed contribution to the description of this problem.

The process of near-electrode polarization in a polyvinylidene fluoride (PVDF) film was studied using reverse currents Irev(t). It was proven that the maxima on the Irev(t) curves are characteristic of near-electrode polarization. The dependences of the reversal currents on time were analyzed based on various representations. The mobilities of the intrinsic charge carriers in the film and the magnitude of the charge transferred through the dielectric layer from electrode to electrode were calculated. The conductivity of PVDF was studied and analyzed in the temperature range 90°C-130°C.

Quantum key distribution protocols and problems of their protection were studied with the soliton model of entangled photons. There were estimated mutual influences between legitimate users and for any types of cracker attack. For example, BB84 protocol is shown to be unconditional security protocols using photon polarization between outlying channels. Secret keys share quantum state between spatially separated (removed or remote) legitimate users. A simple method of generating a dichotomy signal has also been accomplished. In fact, this method can open the way of probabilistic quantum states. We argue that quantum cryptographic systems can be partially simulated on a classical computer with entangled soliton model. The quantum entanglement is a basic tool of communication and processing of the information.

The calculation of a turbo-expander impeller of a thermoelectric plant operating according to organic Rankine cycle (ORC) is given. The calculation was carried out for real gas using the Peng-Robinson model. Freon R245fa was chosen as the working fluid of the plant. The approximation values of the coefficients of polynomial describing the temperature dependence of isobaric heat capacity on Freon R245fa were used in the calculation.

The main idea of I. Newton in Principia is a description of the laws of motion in Inertial Reference Frames by a second-order differential equation. The variation of the action functional S of stability trajectories equals to zero. The observational error is including the influence of the random fields’ background to the particle. Are we must to use a high-order differential equation for the description in the random fields background? The highorder derivatives can be used as additional variables accounting for the influence of random field background. Trajectories due the influence of the random fields’ background can be called instability random trajectories. They can be described by high order derivatives. Then the stability classical trajectories must be complemented by additional instability random trajectories. Quantum objects are described by the trajectory with neighborhoods. Quantum Probability can describe quantum objects in random fields’. The variation of the action functional S is defined by the Planck constant. For the common description of quantum theory and high-order theory, let us compare r-neighborhoods of quantum action functional with r-neighborhoods of the action functional of a high-order theory.

The experimental results of kinetics of biogas formation for the organic waste utilization are presented for the case where combinations of technological and microbiological methods are used to enhance the process (ultrasonic pre-treatment and coenzyme with a new plant supplement). The plants from Amaranthaceae family are used as plant supplements. The influence of Amaranthus hypochondriacus and Amaranthus retroflexus L. on the process of methanogenesis for poultry wastes is analyzed. Based on the experimental results it is obtained that the maximum daily yield of biogas from substrate including the Amaranthus retroflexus L. and Amaranthus hypochondriacus are 310 ml and 252 ml respectively. For example the maximum daily yield of biogas from substrate without any plant supplements was 211 ml (“pure substrate”). Thus the biogas output rate from poultry waste using the biomass of plants from Amaranthaceae family is 47% higher than standard case. The total biogas yield using the plants supplement from Amaranthaceae family is higher than standard case.

The paper presents the mathematical model and the numerical studies results of heat transfer and hydrodynamics at circulatory heating of the M100 fuel oil in the RVS-3000 tank. Calculations for various inclination angles of the nozzle in the range of 40° to -40° in increments of 10° were made. The winter storage period of fuel oil in the fuel tank is considered. Comparison of the tank heating time up to the hot storage temperature (60°C) and up to the fuel temperature before feeding to the nozzles for combustion (90°C) is performed.

The main idea of I. Newton in Principia is a description of the laws of motion by a second-order differential equation. Classical Newtonian physics can describe stability trajectories in Inertial Reference Frames and some Non-Inertial ones. The variation of the action functional S of stability trajectories equals to zero. The observational error is including the influence of the random fields’ background to the particle. Can we use another description in the form of a high-order differential equation? The high-order derivatives can be used as additional variables accounting for the influence of random fields background. Trajectories due the influence of the random fields’ background can be called instability random trajectories. They can be described by high order derivatives. Then the stability classical trajectories to be complemented by additional instability random trajectories. Quantum objects are described by the trajectory with neighborhoods. Quantum Probability can describe quantum objects in random fields. The variation of the action functional S is defined by the Planck constant. For the common description of quantum theory and high-order theory, let us compare r-neighborhoods of quantum action functional with r-neighborhoods of the action functional of a high-order theory.

Nanotubular and nanoporous structures of ZrO 2 were synthesized by potentiostatic anodization with varying the temperatures of anode in the range of T A = 0 - 90 °C and electrolyte in the range of T El = 20 - 50 °C. It was shown that difference between T A and T El had significant influence on growth rate and morphology type of zirconia nanostructures. Optimal parameters of thermal modes for nanotubular ZrO 2 synthesis were discussed. © 2018 Institute of Physics Publishing. All rights reserved. Act 211 Government of the Russian Federation, contract № 02.A03.21.0006, supported the study. R.V.K. thanks RFBR research project № 18-33-01072 for support. A.S.V. and I.A.W. thank Minobrnauki initiative research project № 16.5186.2017/8.9 for support.

The ejection of ultradispersed diamond from a metallised target surface irradiated by nano- and subnanosecond laser pulses is experimentally investigated. Several targets with different transparent bases (quartz, polymethylmethacrylate) and absorbing metal coatings (titanium, aluminium) are investigated. The effect of the metal layer thickness and pulse width on the range of energy densities in which the ejection of diamond nanopowder is due to the transverse strain of metal layer is analysed. The heating of the target rear surface from which transfer occurs, in dependence of the target and laser pulse parameters, is estimated.

The unitary isobar model MAID2007 has been used to analyze the recent data of pion electroproduction. The model contains all four-star resonances in the region below W=2 GeV and both single-Q^2 and Q^2 dependent transition form factors could be obtained for the Delta, Roper, D13(1520), S11(1535), S31(1620), S11(1650), D15(1675), F15(1680) and P13(1720). From the complete world data base, including also pi- data on the neutron, also Q^2 dependent neutron form factors are obtained. For all transition form factors we also give convenient numerical parameterizations that can be used in other reactions. Furthermore, we show how the transition form factors can be used to obtain empirical transverse charge densities and our first results are given for the Roper, the S11 and D13 resonances., Comment: 8 pages, 11 figures, 4 tables, Proc. of NSTAR2009, Beijing

The paper is devoted to detailed investigation of users' behavior and level of expertise on online medical forums. Two popular forums were analyzed in terms of presence of experts who answer health related questions and participate in discussions. This study provides insight into the quality of medical information that one can get from the web resources, and also illustrates relationship between approved medical experts and popular authors of the considered forums. During experiments several machine learning and natural language processing methods were evaluated against to available web content to get further understanding of structure and distribution of information about medicine available online nowadays. As a result of this study the hypothesis of existing correlation between approved medical experts and popular authors has been rejected.

The investigations of the nonlinear optical parameters of Au, Ag, Pt and Cu colloidal solutions using the Z-scan method and third-harmonic generation (THG) are presented. The nonlinear refractive indices, nonlinear absorption coefficients and Kerr-induced nonlinear susceptibilities (χ(3)(-ω;ω,-ω,ω)) of these solutions on the wavelengths of picosecond and nanosecond Nd:YAG laser radiation (λ = 1064 nm) and its second harmonic (λ = 532 nm) have been measured. A tenfold increase of nonlinear susceptibilities on the wavelength of 532 nm in comparison with λ = 1064 nm is shown for these colloidal metals. The application of colloidal metals as optical limiters of picosecond and nanosecond radiation (λ = 1064 nm and 532 nm) was studied. The influence of aggregation of colloidal clusters on optical limiting in these media was considered. It was shown that the appearance of the long-wave wing of absorption at the final stages of aggregation led to the nonlinear absorption of picosecond pulses. The investigations of the THG of picosecond Nd:YAG laser radiation in colloidal metals (Pt and Cu) are presented. THG efficiency was found to be 7×10-7 for colloidal platinum. Nonlinear susceptibilities χ(3)(-3ω;ω,ω,ω) of colloidal platinum and copper were measured to be (1.5±0.75)×10-14 esu and (1±0.5)×10-14 esu, respectively.

A femtosecond laser (pulse duration 30 fs, centre of the emission spectrum at λ = 1260 nm) with a chromium-doped forsterite crystal was developed. This laser operated on the basis of Kerr-lens mode locking. Synchronous pumping with an Nd3+:YAG picosecond laser resulted in forced generation of femtosecond pulses characterised by an enhanced stability of the output power, which was 5–7 times better than the stability of the pump laser. The output radiation of the forsterite laser was converted efficiently to the second harmonic (central wavelength 630 nm) in a thin nonlinear BBO crystal. The average power of the second-harmonic radiation was 15 mW.

An investigation was made of superluminescent optical parametric oscillators generating visible light when ADP and KDP crystals were pumped with the third and fourth harmonics of a neodymium laser. The conversion efficiency was 70% and the output energy in the form of parametric waves was 0.35 J. The advantages of the third harmonic of a neodymium laser as the pump radiation, over the fourth harmonic, were demonstrated.

It is shown that complete conversion of the pump wave energy into amplified waves may be achieved for a specific relationship between the profile of the spatial–temporal modulation of a seed signal and the pump. Numerical calculations are used to find the maximum conversion efficiencies for waves with different spatial–temporal modulations.