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The study aimed to evaluate the hypoglycemic activity of lactic acid bacteria isolated from the medicinal plants possessing antioxidant and hypoglycemic properties growing in Uzbekistan and analyze their prоbiotic properties. Four plant isolates of lactic acid bacteria (LAB) and three commercial strains were used in the study. Alimentary hyperglycemia was induced in white outbred rats, and glucose level was measured before and after treatment with lactic acid bacteria according to the experiment scheme using an intraperitoneal glucose tolerance test. The investigation was shown that strains of Lactobacillus kunkeei 1, L. рlantarum TK1, L. рlantarum KA3, Enterococcus faecium effectively reduce postprandial hyperglycemia in rats. Moreover, evaluation of their probiotic properties: sensitivity to antibiotics, simulated gastric juice, simulated juice of small intestine, bile, and elevated concentration of sodium chloride, demonstrated that the strains Enterococcus faecium 1, Lactobacillus kunkeei 1, L. рlantarum TK1, L. рlantarum KA3 meet the criteria for probiotics. These strains could be considered promising candidates for the preparation of probiotic preparations intended not only to correct gut microbiota but also to maintain normal blood glucose levels.

School leadership has become a priority in education policy agendas internationally. It plays a key role in improving school outcomes by influencing the motivations and capacities of teachers, as well as the school climate and environment. Effective school leadership is essential to improve the efficiency and equity of schooling. The following article emphasizes the importance of school leadership and managing staff and makes suggestions to strengthen school management.

A hydrodynamic model of motion of compressible liquid in a complex profile pipeline has been built and the resulting coupled equations have been solved. The dynamics of the liquid flow rate was determined in dependence on parameters of the system and inlet and outlet pressure variation.

This article analyzes the relationship and influence of factors such as the population, the level of motorization, economic development, and the state of the state road network on the state of the risk of road accidents, including the level of mortality and road injuries, as well as the relevance of improving methods for assessing, managing and predicting the risk of accidents in road traffic. National indicators of the level of road deaths and injuries in different countries were studied. The relationship between road accidents and the level of motorization, income of the population, the state of the road network, and other indicators were revealed. The urgency of the problem of road accidents and the organization of measures to reduce the level of road accidents is emphasized. It also takes into account the special importance of forming conceptually new approaches to the task of improving the efficiency of public administration in the field of organization and maintenance of road traffic through the implementation of the Concept of Road Safety in the Republic of Uzbekistan for the period 2018-2022, which includes the following main directions: further improvement of the regulatory framework in the field of road safety, including significant strengthening of responsibility for gross violations of traffic rules; comprehensive improvement of road infrastructure, improving the quality of roads, creating reliable conditions for the safe movement of vehicles; improving the legal culture, the necessary knowledge, and skills of road users, strengthening their discipline.

Ushbu maqolada O'zbekiston Respublikasi sharoitida yo'llar va ko'chalardan foydalanishda xavflardan yuzaga kelishi muammosiga bag'ishlangan.

Based on theoretical investigations, the influence of various forms of pressure variation at the wellhead with a nonstationary flow of a two-phase fluid in a bed–well system on the character of change in the bottom-hole pressure has been investigated, which makes it possible to determine this pressure from the wellhead operation parameters. The trapezoidal form of the change in pressure is considered as an example. The coupled equations of filtration and the equations describing nonstationary motion of a gas–liquid mixture in a pipeline have been solved jointly. Analytical formulas have been obtained allowing one to determine the bottom-hole pressure from the technological parameters at the wellhead with account for the dynamic connection of the bed–well system at different forms of change in the wellhead pressure. The influence of the wellhead pressure pulsation frequencies on the bottom-hole pressure dynamics has been established.

We have undertaken a theoretical study of the hydrodynamics of fluid motion in communicating vertical pipes with different forms of vibrowave effect in the wellhead. The dynamics of the propagation of elastic waves and pressure in the zone of fluid crossflow from one pipe into the other has been examined. The character of change in the bottom-hole pressure has been determined. It is shown that in the case of a sawtoothedchange in the pressure of the fluid pumped into the wellhead, the variation in pressure in the zone of fluid crossflow from one pipe into the other occurs in the form of beats.

The smectic C* based on a three-component mixture of liquid crystals (LC) with not mesogene chiral additive and showing ferroelectric properties has been developed. The physical parameters which are responsible for electrooptical effects are defined. The Clark–Lagerwall effect both in the pure smectic C* and with the additive of small particles of the centrosymmetric substance Al2O3 and the ferroelectric SrTiO3 is investigated. It has been shown that time characteristics of a cell with LC-Al2O3 are a little bit worsened in comparison with a cell with pure LC. It is caused by increase of the rotational viscosity of the ferroelectric liquid crystal with addition of small particles Al2O3. Time characteristics of the Clark–Lagerwall effect in the LC-SrTiO3 cell essentially surpass time characteristics of the cell with pure LC because the transition from the deformed UP-state to the DOWN-state demands overcoming much lower energy than the transition from the pure UP-condition to the DOWN-state.

Introduction. Liquid crystals (LC) are anisotropic optical media which have found broad application, in particular in LC displays and other photonic devices in the visible range. Little attention has been focused on studying LCs for conversion of radiation in the IR region of the spectrum, even though CO2 and other IR lasers are used in industry and medicine. Well-oriented nematic LC samples are strongly birefringent media, and are characterized by ordinary and extraordinary refractive indices no and ne. An electric field can change the orientation of LC molecules (the Frederiks effect), leading to a change in the effective refractive index along the direction of propagation of the light. In this case, the long axes of molecules of an LC with positive dielectric anisotropy are aligned parallel to the field direction, while in an LC with negative dielectric anisotropy they are aligned perpendicular to the field. This is a fundamental property of liquid crystals, and the basis for the operating principle of most photonic devices. Earlier in [1] a method was proposed for controllable filtration of IR radiation, based on a combination of the Frederiks effect and the Christiansen effect. The latter effect arises if particles are dispersed in a sufficiently transparent medium and the particle sizes are comparable with the wavelength of the incident light. In this case, the system transmits light in a narrow range of wavelengths, where the refractive indices are close for the particle material and the medium in which the particles are dispersed. Using LCs made it possible to control the position of the transmission maximum of the system when an electric field is applied. Application of this effect is also possible for a fixed value of the applied voltage (by varying its frequency). In this case, we propose using a dual-frequency LC as the medium in which the particles are dispersed, where the LC has positive anisotropy of the dielectric constant at low frequencies of the applied electric field and negative dielectric anisotropy at high frequencies. Aluminum oxide is used as the particle material; the refractive index of aluminum oxide varies considerably in the IR region of the spectrum [2]. In this paper, we present the results of a study of the Christiansen effect in an aluminum oxide particles — dual-frequency LC system.

Optical absorption of the nematic liquid crystal 4-methoxybenzilidene-4′-butylaniline (MBBA) was examined to study a possibility of homogenous orientation of liquid crystalline (LC) molecules on the silicon and germanium substrates subjected to argon ion bombardment. The integral absorption near the 1630 cm−1 absorption band maximum, commonly assigned to the group -CH˭N- vibrating along the MBBA long axis was analyzed before and after the application of the electric field above the threshold voltage of the Fredericksz effect. It was shown that upon increasing ion fluences, the preliminary bombardment of the substrates by argon ions with energies of 250 eV lead to the planar molecule orientation. Argon ions of 1.25 keV, however, promote planar orientation only until fluences of the order of 1 · 1018 ion · cm−2 and change the orientation for homeotropic at higher fluences.

A new method for closed lavsanoplasty of the knee ligaments and an instrument suggested for its performance are described. The method is applied successfully in the clinic for the treatment of patients with neglected ruptures of the knee ligaments. The article shows the advantages of the method over those previously existing, which is evidence that its wide use in Soviet medical practice is promising. The work also deals with the force parameters of stretching of the implanted ligament, which were determined for the first time, in experiments and in the clinic, owing to the created measuring device Surgical apparatus for lavsanodesis.

The work is based on the analysis of examination and treatment (external +transosseous osteosynthesis) of 172 patients with ununited fractures and false joints of the long tubular bones complicated by purulent infection and posttraumatic osteomyelitis. All patients were divided into 4 clinical groups according to the activity of the purulent wound infection and choice of the surgical tactics. Some risk factors were taken into consideration in choosing the tactics of treatment and predicting the outcomes. The clinical course of the wound process in the groups of the patients studied and the errors and complications of operative treatment are analysed. The necessity for active postoperative management of patients and endolymphatic and +intra-arterial administration of antibiotics is substantiated. Good and satisfactory results of treatment were produced in 85.6% of patients.

The authors have proposed a method of surgical treatment of posttraumatic coxa vara. The treatment was given to 19 patients aged 16 to 43 years. The essence of the operation consists in oblique intertrochanteric osteotomy of the femur, osteotomy of the lesser trochanter and a muscular pedicle graft formation from the lesser trochanter which is used in grafting the defect observed after the correction of the spatial position of the proximal end of the femur.

In this paper we consider the influence of solid boundaries on the transition temperatures of a chiral smectic C liquid crystal. Particular attention has been paid to the S*C–SA transition. A simple model to explain the thickness dependence of the S*C–SA transition is proposed. An experimental method to determine some elastic constants and the anchoring energy of ferroelectric liquid crystal molecules is demonstrated.