Intermolecular interactions of decamethoxinum and acetylsalicylic acid in systems of various complexity levels

Intermolecular interactions between decamethoxinum (DEC) and acetylsalicylic acid (ASА) have been studied in the phospholipid-containing systems of escalating complexity levels. The host media for these substances were solvents, L-α-dipalmitoylphosphatidylcholine (DPPC) membranes, and samples of human erythrocytes. Peculiar effects caused by DEC-ASА interaction have been observed in each system using appropriate techniques: (a) DEC-ASА non-covalent complexes formation in DPPC-containing systems were revealed by mass spectrometry with electrospray ionization; (b) joint DEC-ASА action on DPPC model membranes led to increasing of membrane melting temperature Tm, whereas individual drugs caused pronounced Tm decreasing, which was demonstrated by differential scanning calorimetry; (c) deceleration of DEC-induced haemolysis of erythrocytes under joint DEC-ASА application was observed by optical microscopy

САТУРАЦИОННАЯ БИОПСИЯ ПРЕДСТАТЕЛЬНОЙ ЖЕЛЕЗЫ (ОБЗОР ЛИТЕРАТУРЫ)

Prostate biopsy is the principal method of diagnois of prostate cancer, allowing to start the adequate treatment. The tactics of the patients, which have negative initial biopsy, is a subject of discussion. Saturation biopsy is a “gold standard„ of diagnostics of PCA with repeat biopsy. Saturation biopsy of the prostate is not a primary procedure, usually apply in patients with negative biopsies in anamnesis, patients with multifocal PIN and ASAP. Saturation biopsy allows to more precisely predict the volume and degree of malignancy of PCA, that can be used for planning tactics of active surveillance and focal therapy.Биопсия предстательной железы является основным методом диагностики рака предстательной железы (РПЖ), позволяющим начать своевременное адекватное лечение. Тактика ведения больных, у которых первичная биопсия была отрицательной, остается предметом дискуссии. «Золотым стандартом» диагностики РПЖ при повторной биопсии является сатурационная биопсия. Сатурационная биопсия предстательной железы не показана как первичная процедура, обычно она используется у мужчин с отрицательными биопсиями в анамнезе, но с сохраняющимся подозрением на РПЖ, у пациентов с мультифокальной простатической интраэпителиальной неоплазией и наличием атипичной мелкоацинарной пролиферации. Сатурационная биопсия позволяет более точно прогнозировать объем и степень злокачественности опухоли, что может быть использовано для планирования тактики лечения

Algorithm for the synthesis of linear antenna arrays with desired radiation pattern and integral amplitude coefficients

Ahe problem of technical implementation of phased array antennas (PAR) with the required radiation pattern (RP) is the complexity of the construction of the beamforming device that consists of a set of controlled attenuators and phase shifters. It is possible to simplify the technical implementation of PAR, if complex representation of coefficients of amplitude-phase distribution of the field along the lattice is approximated by real values in the synthesis stage. It is known that the amplitude distribution of the field in the aperture of the antenna array and the radiation pattern are associated with Fourier transform. Thus, the amplitude and phase coefficients are first calculated using the Fourier transform, and then processed according to the selected type of circuit realization of attenuators and phase shifters. The calculation of the inverse Fourier transform of the modified coefficients allows calculating the synthesized orientation function. This study aims to develop a search algorithm for amplitude and phase coefficients, taking into account the fact that integer-valued amplitudes and phases are technically easier to implement than real ones. Synthesis algorithm for equidistant linear array with a half-wavelength irradiators pitch (&l;/2) is as follows. From a given directivity function the discrete Fourier transform (DFT) in the form of an array of complex numbers is found, the resulting array is then transformed into a set of attenuations for attenuators and phase shifts for phase shifters, while the amplitude coefficients are rounded off to integers, and phases are binarizated (0, ?). The practical value of this algorithm is particularly high when using controlled phase shifters and attenuators integrally. The work confirms the possibility of a thermoelectric converter of human body application for an electronic medical thermometer power supply

Method of measuring the amplitude directivity pattern of parabolic mirrored antennas in the audio frequency range

Directivity pattern (DP) or graphical representation of the dependence of gain factor (directivity gain) of antennas on the direction of the antenna in the target plane is the main characteristic that describes its directional properties. Running DP measurements directly in the microwave range is very expensive. While generating and receiving devices for the acoustic frequency range are reasonably priced. In this paper, we propose a method for measuring the amplitude directivity pattern of parabolic mirrored antennas on the basis of sound equivalent, which is based on the identity of the numerical values of the directivity gain of microwave range, and at audio frequencies. The paper presents analytical expressions for the calculation of equivalent frequency and defines the requirements for the minimum size of the antenna. The paper contains a modified block diagram for an amplitude directivity pattern meter for parabolic mirrored antennas in the audio frequency range

SATURATION BIOPSY OF THE PROSTATE (REVIEW)

Prostate biopsy is the principal method of diagnois of prostate cancer, allowing to start the adequate treatment. The tactics of the patients, which have negative initial biopsy, is a subject of discussion. Saturation biopsy is a “gold standard„ of diagnostics of PCA with repeat biopsy. Saturation biopsy of the prostate is not a primary procedure, usually apply in patients with negative biopsies in anamnesis, patients with multifocal PIN and ASAP. Saturation biopsy allows to more precisely predict the volume and degree of malignancy of PCA, that can be used for planning tactics of active surveillance and focal therapy

High-speed algorithm for carrier frequency recovery and frame synchronization in QPSK-modulated modems

When demodulating signals in communication systems with QPSK modulation operating in the pulsed mode, the following problems arise: rapid elimination of the reference oscillator phase ambiguity and ensuring reliable frame synchronization for a given noise immunity. In most QPSK modems, the carrier frequency recovery and synchronization recovery tasks are separated and solved with the help of different functional modules, which is not the optimal solution from the point of view of increasing the energy efficiency. In this paper, we propose a fast algorithm for frame synchronization and recovery of the carrier frequency of a QPSK modem using Barker sequences as synchronization signals in conjunction with the coordinated processing. The simulation of the combined circuit is performed, which allows to eliminate the phase ambiguity of the reference oscillation with the simultaneous formation of the frame synchronization signal for various combinations of binary sync codes of the length N = 7. To obtain a reference oscillation, a stable quartz oscillator is used. An external adjustable phase shifter block abruptly changes the phase of the oscillator, and the phase ambiguity, which is multiple of 90°, is eliminated by parallel analysis of all possible rotations of the signal constellation plane in the units, each of which contains a pair of filters matched to the signal distributed over in two quadratures. The timing for the proposed scheme does not depend on the initial phase difference between the received and the initial signal constellations, while the circuit realization of a non-tunable oscillator is much simpler than that for a voltage controlled oscillator

Correlation scheme of frame synchronization in communication systems with QPSK-modulation

The information efficiency of communication systems using quadrature amplitude modulation is reduced because of the costs for data transmission necessary to provide frame synchronization and the required time to search for the sync signal and to go into the tracking mode of the synchronization system. One of the most effective schemes of constructing a frame synchronization system is the correlation diagram. In order for this diagram to operate, signal-code constructions with good aperiodic autocorrelation properties are required. The aim of this study is to develop an effective frame synchronization system for quadrature modulation communication systems based on binary signal-code sequences with an ideal sectioned non-periodic autocorrelation function. In this paper, we propose a frame synchronization scheme for QPSK modulation based on binary sequences of even length with an ideal autocorrelation function. All binary synchronous sequences of length N = 8 with the idealness of the autocorrelation function are analytically found in the study. On the basis of the chart of the code distance spectrum in the Hamming metric for binary sequences of N = 8 length, it was established that such sequences have a correcting ability that allows correcting single errors. Based on the structural properties of binary sequences of N = 8 length, sequences of a larger multiple length (N = 16, N = 32, etc.) can be synthesized. The practical value of the proposed scheme of frame synchronization is to reduce the complexity of technical implementation and increase the overall noise immunity of the communication system. The proposed approach can be successfully used to synchronize communication systems with QAM modulation with a large number of signal positions such as QAM 16, QAM 64, etc

Measurement of the amplitude pattern and the frequency characteristic of ISM-band antennas using WiFi routers

The quality of wireless network depends essentially on the directional characteristics of the antennas, the most important of which are the amplitude radiation pattern (RP) and the frequency response (FR), which is understood as a change of the gain coefficient in the working frequency band. At the same time, equipment for measuring the characteristics of the antennas in real conditions is very expensive, difficult to deploy, configure and maintain. In most cases, the measurement accuracy requirements are significantly lower than in laboratory measurements. This fact allows using the equipment which is part of the wireless network itself. The aim of this work is to develop a simplified procedure for measuring the amplitude RP and frequency characteristics of antennas for the rapid assessment of electromagnetic environment during deployment of wireless networks, when the requirements for measurement accuracy are not critical. In this article we propose to use as a UHF calibrated power generator a standard Wi-Fi router with a coaxial output, i.e. with the possibility to connect an external antenna. Certified routers 802.11n standard of 2.4 GHz band, regardless of the manufacturer, provide the following parameters: output power range of 20-100 mW, receiver sensitivity of 80-85 dBm, dynamic range of the receiver - 90 dBm. Using system settings of the router allows one to rapidly change the frequency in the range of 2400-2483.5 MHz with a step of 5-20 MHz. The practical value of the proposed methodology for measuring Wi-Fi antennas characteristics consists in substantial saving of time and costs during deployment and adjusting of wireless networks. This method can be successfully used for testing city wireless video surveillance systems and public access points to the local and global resources of city network

Imitator of signals for plan-position indicator «Picket»

The authors have developed a device for imitation of the signal-interference environment for radars, equipped with the plan-position indicator (PPI) «Picket», which does not require a PC for operation. Thanks to the use of the original method of forming marks from targets, it was possible to significantly reduce the amount of memory, required to store information about the scenario that reliably imitates the operation of the radar in real conditions. The device provides simultaneous operation of twelve indicators of a circular survey and is intended for equipping training centers for the training of air control operators