卷 474, 编号 1 (2017)

In the psychophysical experiments reported here, cochlear compression function was derived by comparing on-frequency and off-frequency masking. The signal was rippled spectrum noise. The ripple density discrimination threshold was measured in the ripple phase reversion test. An increase in masker intensity led to a decrease in a resolvable ripple density threshold. The on-frequency masker level at threshold increased proportionally to the signal intensity. The off-frequency masker level at threshold also increased proportionally to the signal at signal intensity levels below 50 dB, whereas at signal levels above 60 dB SPL, the ratio of the masker level at threshold gradient to signal level gradient was 1 : 5 dB/dB, revealing cochlear compression.

Genetic diversity of the genus Blarinella was studied using one mitochondrial and four nuclear genes as examples. The first genotyping of shrews from the southeast of Gansu province (China), which is a typical habitat of B. griselda, has been performed. Molecular genetic analysis showed that Blarinella sp. from southern Gansu stand apart among the other representatives of the genus and can be assigned to neither of the known species.

The first description of the quantitative and qualitative compositions of the littoral fauna of Grønfjorden Gulf during the winter and spring period is given. Granulometric analysis of the surface sediments of the littoral has been performed. Thirty invertebrate taxa that did not leave the littoral zone during wintertime and could survive complete freezing during ebb have been identified. Species diversity and population density of the invertebrates were shown to depend on the granulometric size composition of the surface sediments.

The alarm call acoustic structure and nonlinear vocal phenomena of the Indian sambar (Rusa unicolor) and northern Indian muntjac (Muntiacus vaginalis) have been analyzed in detail as well as their vocal behavior in response to mobbing humans under natural conditions of southern Vietnam. The alarm calls of sambars, tonal barks separated by large intervals, were produced by animals standing on the place and gazing at a potentially dangerous object. Muntjacs flee off in danger and produced a series of dull barks interrupted with short intervals from a distance. The alarm call frequencies were characterized for sambars and muntjacs. The results of our study have been compared with the published data on alarm calls of other Cervidae species.

The paper reports spontaneous generation of weak electric discharges with an amplitude of 0.4–1.0 mV and a frequency of 3–9 min^–1 by solitary Synodontis caudovittatus fish. When fish individuals were tested in pairs, their aggressive–defense interactions were associated with an increase in the amplitude of the discharges (up to 30–45 mV) compared to the discharges of individual fish, while the duration of the pulses increased up to 20–25 ms due to the prolongation of the second phase. In S. eupterus, electric activity was recorded only in the course of aggression–defense interactions, while spontaneous generation of discharges was not observed at all. The paper discusses the different aspects of electrocummunication between the catfish including the role of the reversion of polarity of the merged summated discharges with increased duration.

High prevalence of non-AIDS-defining illnesses in treated HIV-infected patients is associated with increased peripheral CD8⁺ T cell counts. Hepatitis C virus (HCV) coinfection is an additional risk factor for the development of non-AIDS events. We found that, in HIV/HCV coinfection, the increased proportion of CD8⁺ T lymphocytes is due to the effector memory and terminal effector T cells gain. Moreover, in these patients, the accumulation of highly differentiated forms of CD8⁺ T lymphocytes was associated with increased concentrations of inflammatory indices.

Changes in sleep characteristics were studied under the non-wake-up stimulation with current pulses of less than 1 μA on average, applied to the palmar surface skin receptors during Δ-sleep. A significant increase in duration of the first and second cycles of deep sleep has been found, as well as a shorter latent period before the Δ-sleep onset and a longer time of the rapid sleep (REM phase). The sleep structure improvement was accompanied by the reduced reactive anxiety and depression and an increase in subjective physical efficiency.

Sings of meromixis are found by means of microbiological and biogeochemical investigations in the southernn part of the Kanda Bay, an artificial water body separated front the White Sea with a railway dam. The concentration of oxygen in the bottom layer attained 1.9 mmol/L, intensity of the process of microbial sulfate reduction, 3.0 μmol of sulfur/(L day). The concentration of dissolved methane, 3.7 μmol/L. Isotopic composition of carbon in methane (δ¹³C (CH₄) =–79.2‰) indicates to its microbial genesis. At present, Kanda Bay is a sole in Russia man-made marine water body for which there are data on the rate of microbial processes responsible for formation of bottom water layer containing hydrogen sulfide and methane.