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Lice (Anoplura) were studied in 2015–2018 in the middle taiga of West Siberia in the territory of the Middle Ob region (Khanty-Mansi Autonomous Okrug–Yugra). Lice were found on 15 species of small mammals, of which the most significant hosts were Alexandromys oeconomus, Microtus rossiaemeridionalis, M. agrestis, Myodes glareolus, and M. rutilus. The louse Hoplopleura acanthopus had the widest host range and was also dominant among all the louse species found on small mammals. The peaks of louse abundance coincided with those of host reproductive activity in late spring and early autumn. In the most common host A. oeconomus, the highest degree of infestation (mainly with H. acanthopus) was recorded in adult males; the corresponding indices were significantly lower in adult females and especially low in young mammals. The population structure of H. acanthopus showed prevalence of females (about 50%) in comparison with males and larvae. Co-parasitism of lice was especially pronounced on adult host specimens. The lice Hoplopleura edentula, Hoplopleura longula, and Polyplax hannswrangeli were recorded for the first time from the studied territory.

The purpose of the researchis establishing the composition, infection rates, species and group ratio of ectoparasites of the East European vole on the northern border of the range in Western Siberia (Middle Ob Region).Materials and methods.In 2015–2018, in order to capture the provider of ectoparasites, the East European vole, we used methods of trap lines, trap trenches, and fence-traps; we recorded 173 animals from which we collected 881 specimens of gamasid mites, ixodic ticks, lice and fleas. To assess the quantitative indicators of ectoparasites, the indices generally accepted in parasitology were used.Results and discussion.In 2014, it was established for the first time that there is a sibling species of the common vole, the East European vole in the Middle Ob Region (middle taiga of the forest zone of Western Siberia). In the city of Surgut and its neighborhood, this animal is confined to the most transformed biotopes. The ectoparasite complex of the East European vole includes 26 species of parasitic arthropods. By the number of species (13) and individuals, gamasid mites predominate, and the proportion of ixodic ticks, lice and fleas put together is almost 3 times lower. In a climate of the Middle Ob Region, the list of ectoparasites will no doubt grow as the range of habitats expands and the contacts of the East European vole with other small mammals increase, and its role in maintaining pathogen circulation of natural focal infectious diseases will increase.

The present work studied the effect of aqueous extract from Feijoa leaves on thyroid function of rats with experimental hypothyroidism. Healthy albino rats weighing between 120 gand 150 gwere used. The animals were randomly allotted into four groups, each containing eight rats respectively. Three of the groups (II, III and IV), induced with hypothyroidism, were treated by 0.05 % solution of thiamazole with drinking water for 30 days. Control (vehicle) rats were given normal saline. After 13 days hypothyroid groups (III and IV) of rats were treated with aqueous extract from Feijoa leaves at a dose 1.0 ml/100 g of body weight and with Iodomarin 200 (reference drug) at a dose 12 µg/kg daily orally for 21 days. Results obtained from the study showed that the introduction of thiamazole leads to functional changes in the thyroid gland in rats, accompanied by decreasing sings of rectal temperature and level of thyroid hormones. It was found, that treatment with AEFL normalizes serum thyroid hormone levels, increases rectal temperature and reduces the thyroid mass. The investigated extract can be attributed to the regulators of the thyroid hypofunction and is promising for further study of its effectiveness as a thyroid-stimulating agent.

The herb wood mouse is parasitized by Hoplopleura affinis Burmeister, 1839. For this research, the authors examined a total number of 408 herb wood mice for the presence of permanent ectoparasites (lice). The authors considered changes in the infestation rate in connection with the periods of the rodent’s life, the age and gender composition of the lice, the biotopic confinement peculiarities of the parasite in the conditions of the Trans-Urals forest steppe (Kurgan region). H. affinis is noted to be found on mammals in contact with the herb wood mouse.

For this the research, 2035 individuals of small mammals of 18 species were examined in order to find out the presence of obligate hematophages (Anoplura); from those 984 lice of 5 species were collected. The species composition of Anoplura, the indices of occurrence, infestation and the abundance of Anoplura on the Insectivora and Rodentia were analyzed. There have been noted repeated cases of Anoplura parasitizing the mammals unusual for them, which reflects interspecific contacts of small mammals. The features of the biotopic confinement of the parasite were considered.

A concept for designing network systems for underwater observations based on the joint development of hydroacoustic radiating and receiving elements integrated with different channels of communication is discussed. The main requirements for such systems, principles, and algorithms of their operation under nonstationary conditions of actual marine waters are formulated. The results from several numerical and field experiments demonstrating the performance of certain elements of such systems in typical shallow water basins are presented.

The present work studied the effect of aqueous extract from duckweed Lemna minor frond on morphological state of the thyroid gland in the experimental hypothyroidism. Healthy albino rats weighing between 120 g and 150 g were used. The animalswere randomly allotted into four groups, each containing ten rats respectively. Three of the groups (II, III and IV) induced with hypothyroidism by 1 % solution of sodium perchlorate with drinking water for 20 days. Control (vehicle) rats were given normal saline. After 20 days hypothyroid groups (III and IV) of rats treated with aqueous extract from duckweed Lemna minor frond at a dose 0.5 ml/100 g of body weight and with Iodomarin 200 (reference drug) at a dose 12 µg/kg daily orally for 21 days. Results obtained from the study showed that the introduction of sodium perchlorate leads to morphological and functional changes in the structure of the thyroid gland in rats, accompanied by sings of hyperplastic tissue proliferation and corresponds with hypofunctional state. It was established that introduction of aqueous extract from duckweed Lemna minor frond has a positive effect on the restructuring of the thyroid gland in rats with hypothyroidism, increasing its functional activity. There is a decrease of proliferative processes by extrafolliсular epithelium and thyrocytes in the follicles. The outer diameter of follicles decreased by 7.65 % (P>0.05), the height and size of thyrocytes in the wall of the follicle were significantly decreased by 58.16 % and 18 41 %, respectively, compared to untreated hypothyroid group. The obtained results have practical significance for the development of drugs with thyroid-stimulating action for preventing or delaying the development of hypothyroidism and its complications.

The herbal tea of previously patented composition for the treatment of urinary diseases containing twelve plants (St. John's wort, Wild pansy, Horsetail field, Common heather, Elecampane i.a.) was analyzed for the qualitative composition and quantitative content of phenolic compounds. The diuretic and anti-inflammatory activity of herbal tea thick extract was assessed. The determination of phenolic compounds was carried out by high performance liquid chromatography using standards of phenolic acids and flavonoids. Diuretic activity was checked by the method of Berkhin for the dosage in the range from 100 to 700mg/kg. Level of urination was assessed during 1, 2, and 3 hours of experiment. Edema was induced with 1% carrageenan. The dosage of oral treatment was from 100 to 250mg/kg. Paw volume was checked at time equal to 1, 2, 3, 4, and 5 hours. Several groups of phenolic compounds were detected, and six substances were identified individually. The total content of phenolic compounds was 23.8mg/g, with the content of flavonoids 10.4mg/g and chlorogenic acid 2.7mg/g. The herbal tea showed diuretic activity of 100% growth at the dosage of 200mg/kg. Further increase of dosage led to antidiuretic activity. From the dosage of 500mg/kg we observed the diuretic activity again, which was the highest for the dosage of 700mg/kg showing 271% growth in relation to the control group. The antiinflammatory activity was the highest at the dosage of 200 and 250mg/kg and was equal to 25% in relation to the control group.

A model of fatigue failure in terms of physical processes in the surface layers of materials is outlined, and its parameters are determined. The model may be used to predict the strength and life of auto parts.

The effect of soft X-rays with photon energy W = 8 keV on the kinetics of decay photovoltage in solar silicon crystals is studied. The correlation between the radiation-stimulated change in the electrical characteristics of the investigated crystals and the evolution of their charge, structural state, and surface morphology is established. Also studied are the changes in the photovoltage decay kinetics caused by the action of X-rays on the solar Si – nanofilled polymer coating structures. It is shown that X-ray irradiation leads to quite big recombination losses in the case that the epoxy-urethane matrix contains a filler (polysiloxane particles (PSPs)) in the amount of 0.001 and 1.0 wt. %. At the same time, at PSP filler content of 0.5 wt. %, the passivation epoxy-urethane coatings exhibit an increased radiation resistance.

The possibility of selecting modes that propagate between two spaced observation points without the use of vertical arrays and low-frequency emitters is considered. Modes are selected from the cross-correlation function of noise received by single hydrophones. It is shown that modes at frequencies near the minima of the dispersion dependences of their group velocities, where stationary phase regions are observed, make the main contribution to the noise cross-correlation function. This makes it possible to identify modes of different numbers and estimate their propagation times between hydrophones, which can be the basis for shallow-water passive mode tomography using data from single bottom hydrophones. The modes were selected based on data from a experiment carried out in the Barents Sea.

The paper lays bare the constructive scheme of technological effects of gas and metal plasma flows while exploiting VIP treating to process structural materials and structural changes the surface layer undergo at the technological stages of VIP treating. Moreover, it considers the complex system to ensure the operational properties of structural materials during VIP treating. The application of VIP treating turns out to be exceptionally efficient to reduce damages of the friction unit surfaces under fretting conditions.

We study the possibilities of reconstructings the parameters of the sediment layers of a shallow sea bottom from interference patterns appearing during sounding of the bottom by broadband seismoacoustic sources with a bistatic sea-bottom sounding scheme, adaptive signal reception with a horizontal array, and matched filtration of low-frequency seismoacoustic pulses excited with an air gun and interacting with the sea bottom, as well as seismoacoustic noise from a vessel in a shallow sea. The parameters of sediment layers of the sea bottom are reconstructed by statistical checking of hypotheses on the parameters of dynamic spectra obtained by parametric models. Comparative possibilities of reconstructing sea bottom parameters with bistatic and monostatic observation schemes are discussed.

A simple method is proposed and used for preparing a series of 3-(3-alkylcarbamoyl-4-hydroxy-2-oxo-1,2-dihydroquinolin-1-yl)propanoic acids. A comparative analysis was carried out on the analgesic and diuretic properties of these compounds and their synthetic precursors, namely, the corresponding 1-(2-cyanoethyl)-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxamides.

The possibilities of matching low-frequency underwater sound pulses to the parameters of an oceanic waveguide are considered. The objective is to optimize the system of few-mode tomographic observation in a shallow-water sea. Experimental data are analyzed for two methods of selecting the low-frequency fewmode pulses propagating in a shallow-water sea. The first method excites probe pulses by vertically elongated arrays, with spatial filtering after vertical or horizontal arrays receive the pulses. The second method is based on exciting broadband signals with linear frequency modulation by a single transmitter. The selection of the few-mode signal is performed by time strobing the signals at the output of the matched filter after a horizontal array receives the pulses. The distance between the sound sources and receiving systems varied from 10 to 300 km.

Hydroxy- and alkoxyanilides of 6-hydroxy-2-methyl-4-oxo-2,4-dihydro-1H-pyrrolo[3,2,1-ij]quinoline-5-carboxylic acids have been synthesized as potential diuretic agents. Features of their purification, their steric structure, and biological activity are discussed.

Possibilities of high-frequency acoustical underwater observations of small-size objects in marine shelf zones are experimentally investigated using vertical and horizontal arrays radiating and receiving complex structure pulses in the presence of strong reverberation. Reconstruction of parameters of the observed objects yielded 35- to 40-dB weakening of the reverberation interferences due to medium-matched spatial, temporal, and Doppler filtering.

Possibilities of formation of coherent high-frequency signals for underwater acoustic observations in shallow-water shelf zones of the ocean with an irregular bottom are experimentally investigated. The methods of medium-conjugate excitation and receiving of complex modulated pulses with the help of vertical and horizontal arrays are probated. It is shown that medium-conjugate spatial, frequency, and time filtering makes it possible to decrease reverberation interferences by more than 40 dB.

A series of benzimidazol-2-ylamides of 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acids was prepared in a search for biologically active compounds. These compounds exist in the crystal exclusively in the amide form, while in solution amide↔imide tautomerism is observed. The results of a study of the antithyroid and antituberculosis activities of these compounds are given.

It has been pointed out that the main criterion for attaining minimum coefficients of friction and high resistance to wear for polymer-based antifriction composites should be their ability to spontaneous formation of a two-layer film on the friction surface, which combines the lubricating ability and high adhesion.

The problem of phasing linear hydrophone arrays lying on the bottom of the Barents Sea is discussed by using the results of a full-scale experiment. In the experiment, a pulsed pressure source was used as a source of sound and three linear hydrophone arrays positioned at different sites served as receivers. For signals at the array’s apertures, the spatial correlation interval is estimated. Output responses of the arrays are compared with and without allowance for the spatial correlation interval of the sound field.

Anisotropy of the piezoresistance relaxations has been observed in p -(0 0 1)GaAs/Al 0.5 Ga 0.5 As heterostructures. The character of relaxation process depends on the direction of the applied uniaxial compression: after loading along [1 m 1 0] direction the specimen resistance relaxes down to the lower magnitude while after loading along [1 1 0] direction it relaxes up to the higher magnitude. Shubnikov-de Haas oscillations and Hall effect measurements indicate that variation of the carrier concentration j N in the quantum well during relaxation processes has different signs for uniaxial compression along [1 m 1 0] and [1 1 0] directions and correlates with the corresponding change of the resistance. The piezoelectric field that in GaAs can reach the magnitude E =1.152 2 10 6 V/m at uniaxial stress P =1 kbar along d 1 1 0 ¢ directions is supposed to be responsible for the metastable state after loading (unloading) and redistribution of carriers during the relaxation process.

Long-term resistance relaxations induced by uniaxial compression in (001)p-GaAs/Al0.5Ga0.5 As heterostructures are observed, and the main properties of these relaxations are investigated: the dependence of their character on the direction of the uniaxial compression, the change in concentration of current carriers during the relaxation processes, and the quenching of the relaxations by temperature, illumination, and high electric fields. It is found that the character of the relaxation process is different for compression directions [110] and \([1\bar 10]\): in the first case the concentration of two-dimensional holes in the quantum well decreases in the course of the relaxation, while in the second case it increases. A model is proposed in which the cause of the relaxations of the piezoresistance and the anisotropic character of these relaxations is assumed to be the piezoelectric field, the value of which, according to estimates, is |Ez| = 1.152 × 104 V/cm per kbar.

Resistance, magnetoresistance, and their temperature dependencies have been investigated in the two-dimensional hole gas at a [001] $p$-type ${\mathrm{G}\mathrm{a}\mathrm{A}\mathrm{s}/\mathrm{A}\mathrm{l}}_{0.5}{\mathrm{Ga}}_{0.5}\mathrm{As}$ heterointerface under [110] uniaxial compression in the range of low and intermediate magnetic fields. Analysis performed in the frame of hole-hole scattering between carriers in the two subbands of the spin split ground heavy hole state indicates that hole-hole scattering is strongly suppressed by uniaxial compression. The value of the parameter \ensuremath{\alpha}, which determines the mutual hole-hole friction coefficient $\ensuremath{\eta}=\ensuremath{\alpha}{T}^{2}$ reveals three times decrease under uniaxial compression 1.3 kbar.

The spectral and kinetic parameters of the X-ray luminescence of ZnSe crystals doped with Zn, Se, and Te were investigated during the growth process at temperatures in the range 80–500 K, and also after annealing in Zn vapor. ZnSe crystals grown from a stoichiometric mixture, or mixture containing chalcogenide impurities, typically produce the minimum level of afterglow and a rapid rise of X-ray luminescence, as well as a shift of its peak from the infrared region toward shorter wavelengths after annealing in zinc. ZnSe crystals grown from material with excess of Zn have a relatively low X-ray luminescence yield and a substantial level of afterglow. It is assumed that the growth of Te-activated crystals is accompanied by the development of thermally stable complexes of the form VZnTeSe that act as radiative recombination centers. The introduction of excess Zn into the initial mixture produces a reduction in the concentration of VZn and, hence, in the concentration of radiative recombination centers. It is shown that, for free-electron concentrations n 1018 cm−3, the time constant decreases with increasing n, which cannot be explained in terms of the simple model. It is suggested that radiative recombination centers of a new type are produced as a result of prolonged annealing in Zn vapor.

A high-power laser system using a neodymium phosphate glass is described. It has an energy ~400 J, a pulse length of 15 ns, and an output aperture of 100 mm. A computer control system allows total remote control. This system makes it possible to monitor the parameters of the laser system, to synchronize its operation with external devices, and to measure and process data from several sensors of various types.

The influence of light illumination and high electric field pulses on the long-term relaxation effect in piezoresistivity which has been discovered recently in p- GaAs/Al0.5Ga0.5As heterostructures has ben investigated. Significant acceleration of relaxation processes has been observed under the carriers heating by different external sources. This means that these phenomena are mostly determined by nonequilibrium processes in electron system. At 4.2 K under high electric fields switching of the samples to long-term high-resistance state has ben also found.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

1. The use of ESR for beryllium bronze eliminates resegregation, reduces the oxygen content, refines inclusions, and improves the ductility. This makes it possible to increase the annual output and to use greater reductions (∼90%). 2. After quenching and aging or MTT of beryllium bronze BNT1.9Mg melted by ESR the bronze has a higher elastic limit and relaxation resistance under conditions of cyclic and static loading, high resistance to creep, high fatigue strength, high electrical conductivity, and higher fracture toughness as compared with standard VI bronze.

One of the basic factors hindering the creation of closed asbestos-cement production is the accumulation in the return water of chromium compounds. The question of removal of chromium from the waste and return waters of asbestos-cement production has still not been solved. The proposed methods of purification are economically unacceptable and are relatively ineffective for the highly alkaline asbestos--cement production waters, which is the basic reason for delay in the introduction of these methods into production.

Alkyl-, arylalkyl-, and arylamides of 2-hydroxy-4-oxo-4H-pyrido[1,2-a]pyrimidine-3-carboxylic acid were prepared with a view to establishing a structure-biological activity relationship. A comparative analysis has been made of their diuretic properties and those of the structurally similar 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxamides.