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Introduction. Dynamic monitoring and evaluation of the results of therapy of patients with malignant brain diseases is a complex and urgent problem in modern medicine. The aim of the study was to assess the reliability of the transcranial magnetic stimulation technique as a tool for neurophysiological monitoring in patients with malignant brain tumors. Material and methods. Two groups of patients were formed: adults with large focal solitary lesions of the central nervous system (glioma) (n=20), who underwent radiotherapy, and a control comparison group (n=16). All patients underwent diagnostic transcranial magnetic stimulation before and after treatment. Results. In the main group the application of transcranial magnetic stimulation in dynamics allowed to reveal reliable improvement of conduction along the central motor pathways (increase in amplitude of the evoked motor response). The obtained data of neurophysiological examination correlated with clinical improvement in the patient group. Discussion. Some parameters of the motor evoked response (MEP) changed reliably, as after the radiation treatment performed. Obtained changes (amplitude of MEP and, especially, its threshold) to the greatest extent reflect functional state of cortical motoneurons, as well as their anatomical preservation in case of organic changes. Before therapy in all cases there was a reliable tendency to a smaller amplitude and a higher threshold of cortical MEPs, which reflects a decrease in the functional activity of motor cortex neurons; a slower central motor conduction time also draws attention. These changes had a universal character and were registered in all patients. Conclusion. Diagnostic transcranial magnetic stimulation, taking into account age limitations inherent to it as a technique, is a valuable additional neurophysiological technique. It is safe, inexpensive and does not require expensive consumables, and is applicable to a wide range of diseases.

This article contains the results of research on the topical problem of highly sensitive express registration of biological objects using field-effect transistors with the surface open for analyte access, which are made based on silicon-on-insulator (SOI) films. The possibilities of dielectrophoretic effects for controlling the concentration of the analyte in the area of sensory elements are considered on the example of the indication of viruses of nuclear polyhedrosis and vaccinia. It is shown that the use of the dielectrophoresis (DEPh) effect makes it possible to solve (1) the key tasks for creating sensor systems: increasing the detecting ability, as well as exrtacting and verifying the signal from the target particles; and (2) the fundamental task: determining the charge state of the analyte in solutions without modifying the sensors’ surface. The problems and prospects of the mass application of nanowire (NW) biosensors, including those with the dielectrophoretic effect, in biotechnology, virology, etc., are discussed.

The results of identifying the vaccinia virus with the use of nanowire biosensors manufactured on the basis of silicon-on-insulator (SOI) films were presented. In our experiments, the vaccinia virus, the LIVP strain from the collection of the State Research Center of Virology and Biotechnology VECTOR of the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, and the rabbit blood serum containing specific polyclonal antibodies to the vaccinia virus were used. As shown by our studies, the polyvalent blood serum was electrically neutral at the sensor surface–viral suspension phase interface, the vaccinia virus was positively charged, and polyvalent blood serum–vaccinia virus vaccine complexes had a negative effective charge.

A method for profiling the components of effective carrier mobility μeff determined by scattering at surface phonons and the roughness of thin film/dielectric interfaces is proposed. The method is based on controlled carrier localization relative to the tested heterointerface due to the interrelation of potentials on opposite film sides (the coupling effect). The method makes it possible to independently separate mobility components near different film heterointerfaces. Its use when studying the electron mobility in silicon-on-insulator films makes it possible to acquire information on the interface roughness and structural perfection of an ultrathin (1–3 nm) silicon layer near the buried film/dielectric interface.

Nanowire SOI biosensors are used to detect the Ebola virus VP40 protein by identifying its immune complexes with specific monoclonal antibodies (MCAs). It is shown that the reaction of specific interaction between VP40 and MCAs causes a more pronounced biosensor response than direct adsorption of VP40 or antibodies to their surface. The formation of antigen — antibody complexes leads to the accumulation of a negative charge on the biosensor surface. The protein and protein — antibody complexes are detected in real time (∼200–300 s per test sample).

A method for forming p-n-diode based silicon electro-optic modulators using local oxidation is tested. It is shown that the local oxidation of silicon allows forming a rib waveguide as a smoothed trapezoid, in contrast to the classical technique of creating a rib waveguide by plasma-chemical etching. The main advantages of the approach used are described: controllability and reproducibility of critical design parameters of the modulators (width and height of the waveguide rib), low surface roughness, and the possibility of using approaches to forming a modulating p-n-diode of combined type in a rib waveguide, which are standard for planar technologies.

The dependences of the electron mobility μeff in the inversion layers of fully depleted double–gate silicon-on-insulator (SOI) metal–oxide–semiconductor (MOS) transistors on the density N e of induced charge carriers and temperature T are investigated at different states of the SOI film (inversion–accumulation) from the side of one of the gates. It is shown that at a high density of induced charge carriers of N e > 6 × 1012 cm–2 the μeff(T) dependences allow the components of mobility μeff that are related to scattering at surface phonons and from the film/insulator surface roughness to be distinguished. The μeff(N e ) dependences can be approximated by the power functions μeff(N e) ∝ N − . The exponents n in the dependences and the dominant mechanisms of scattering of electrons induced near the interface between the SOI film and buried oxide are determined for different N e ranges and film states from the surface side.

The electron mobility µeff in the accumulation mode is investigated for undepleted and fully depleted double-gate n+–n–n+ silicon-on-insulator (SOI) metal–oxide–semiconductor field-effect transistors (MOSFET). To determine the range of possible values of the mobility and the dominant scattering mechanisms in thin-film structures, it is proposed that the field dependence of the mobility µeff be replaced with the dependence on the density Ne of induced charge carriers. It is shown that the dependences µeff(Ne) can be approximated by the power functions µeff(Ne) ∝ Ne-n, where the exponent n is determined by the chargecarrier scattering mechanism as in the mobility field dependence. The values of the exponent n in the dependences µeff(Ne) are determined when the SOI-film mode near one of its surfaces varies from inversion to accumulation. The obtained results are explained from the viewpoint of the electron-density redistribution over the SOI-film thickness and changes in the scattering mechanisms.

Introductions. There has been huge progress in diagnosis and treatment of female sterility recently. Assisted reproductive technologies have become more available for couples who have no children. In Kirov region with population of about 1,5 mln people statistically 47,000 families suffer from sterility.