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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 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.

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.

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.

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.

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.

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.

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.