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1.
Nature ; 627(8005): 805-810, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38448591

ABSTRACT

Stone tools stratified in alluvium and loess at Korolevo, western Ukraine, have been studied by several research groups1-3 since the discovery of the site in the 1970s. Although Korolevo's importance to the European Palaeolithic is widely acknowledged, age constraints on the lowermost lithic artefacts have yet to be determined conclusively. Here, using two methods of burial dating with cosmogenic nuclides4,5, we report ages of 1.42 ± 0.10 million years and 1.42 ± 0.28 million years for the sedimentary unit that contains Mode-1-type lithic artefacts. Korolevo represents, to our knowledge, the earliest securely dated hominin presence in Europe, and bridges the spatial and temporal gap between the Caucasus (around 1.85-1.78 million years ago)6 and southwestern Europe (around 1.2-1.1 million years ago)7,8. Our findings advance the hypothesis that Europe was colonized from the east, and our analysis of habitat suitability9 suggests that early hominins exploited warm interglacial periods to disperse into higher latitudes and relatively continental sites-such as Korolevo-well before the Middle Pleistocene Transition.


Subject(s)
Burial , Human Migration , Radiometric Dating , Humans , Archaeology , Burial/history , Europe , Fossils , History, Ancient , Human Migration/history , Reproducibility of Results , Ukraine , Time Factors
2.
Dokl Biol Sci ; 500(1): 133-137, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34731377

ABSTRACT

A group of 27 healthy young adults solved a task involving the working memory (WM) activation, consisting of the comparison between the spatial orientations of two sequentially presented square-wave luminance gratings. We investigated the effective (directed) connectivity patterns between the frontal and postcentral cortical regions related to the visual system. The connectivity was assessed using vector autoregression modeling of EEG. It was shown that the strength of the top-down right-hemispheric connectivity patterns directed from the frontal cortex to the visual areas in θ frequency was significantly lower at the stage of stimulus retention in the WM than at the stage of stimulus anticipation. On the contrary, in the α band the descending influences were slightly more intense. The results of the study showed the frequency-dependent dynamics of the descending influences of the frontal cortex on visual areas and confirm that the frontal cortex plays the role of a controlling and modulating center in the brain system underlying WM.


Subject(s)
Frontal Lobe , Memory, Short-Term , Brain , Electroencephalography , Spatial Memory
3.
Urologiia ; (3): 121-127, 2020 Jun.
Article in Russian | MEDLINE | ID: mdl-32597598

ABSTRACT

The topic of renal cystic lesions is described in the article. The localization and structure of solitary, parapelvic and multiple sinus cysts are discussed. The Bosniak classification (1986) is presented, as well as the updated Bosniak classification, in which a number of modifications in 2019 were made. The contemporary diagnostic methods are mentioned, as well as factors that allow to select patient for active surveillance. Current surgical procedures are presented.


Subject(s)
Cysts , Kidney Diseases, Cystic , Kidney Neoplasms , Humans , Retrospective Studies , Tomography, X-Ray Computed
4.
Vestn Otorinolaringol ; 83(5): 71-73, 2018.
Article in Russian | MEDLINE | ID: mdl-30412181

ABSTRACT

The objective of the present work was to describe the successful surgical treatment of the peri-lymphatic round window fistula of the labyrinth in the 9 year old child. The authors briefly mention the difficulties of diagnostics of the peri-lymphatic labyrinthine fistulas in the children and the signs suggesting their presence with special reference to the optimal strategies for their treatment.


Subject(s)
Ear, Inner , Fistula , Labyrinth Diseases , Child , Fistula/diagnosis , Humans , Labyrinth Diseases/diagnosis , Retrospective Studies
5.
Dokl Biol Sci ; 482(1): 166-169, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30402750

ABSTRACT

The amplitudes of the P100 and N150 early components of evoked potentials in the visual cortex have been analyzed on 33 volunteers with normal vision during matching between the current orientation and that stored in memory. An increase in the P100 response in the occipital and parietal cortical areas was identified as an informative indicator of mismatch between the current and stored-in-memory orientations. This effect was not found for more complex stimuli, namely, spatial patterns. The N150 component demonstrated a similar effect, but in contrast to P100 it was not stimulus specific. Thus, in the first 100 ms, a signal of mismatch between the current and stored-in-memory orientations arises in the early visual areas that represents a mechanism for early implicit response to changes in the basic characteristics of the visual space.


Subject(s)
Memory, Short-Term , Spatial Memory , Visual Cortex/physiology , Evoked Potentials, Visual , Female , Humans , Male , Young Adult
6.
Fiziol Cheloveka ; 41(3): 5-18, 2015.
Article in Russian | MEDLINE | ID: mdl-26237944

ABSTRACT

The high density EEG was registered in 41 healthy subjects (20 males, 21 females) in the cardinal (horizontal and vertical) and oblique (45 and 135 deg) line orientation identification task. The analysis of the adaptive amplitude maximum (4 ms averaging) of P1 and N1 evoked potentials in the symmetrical occipital, parietal and inferior temporal areas and dipole source modelling showed the anisotropy of cortical responses in the 80-150 ms interval. The amplitude is higher on the oblique orientations as comparison with cardinal ones. The temporal and regional features of cortical answers were discovered. The earlier selective response (~90 ms latency) is registered.in the parietal areas, while the later (~145 ms latency) is found in the occipital ones. We discovered a number of sex-related differences in the early stages of line orientation detection. In males, the amplitude of components is higher; they have broader area of localisation of their dipole sources: in addition to the occipital and parietal regions, cortex of the temporal regions is involved. Theobtained data are discussed in the context of the idea of effective neural coding (Barlow, 1959) and the features of spatial information processing in the visual system of males and females.


Subject(s)
Discrimination, Psychological/physiology , Orientation/physiology , Pattern Recognition, Visual/physiology , Reaction Time/physiology , Visual Cortex/physiology , Adult , Electroencephalography , Evoked Potentials, Visual/physiology , Female , Humans , Male , Neuropsychological Tests , Photic Stimulation , Sex Characteristics , Signal Processing, Computer-Assisted , Young Adult
7.
Article in Russian | MEDLINE | ID: mdl-26841656

ABSTRACT

The high-resolution EEG was taken from 35 healthy subjects (16 males, 19 females) in the task of identification of cardinal (horizontal, vertical) and oblique (45°, 135°) orientations. The integrated approach was developed and used for the ERPs analysis. It includes the modeling of the distributed intracranial dipole sources of the ERPs' components by the weighted Minimum Norm Estimates (wMNE) method, the combination of distributed intracranial dipole sources with the M RI data and the statistical analysis of the current density. It was shown that a multiple network of brain structures was active during the early stage of analysis of line orientation. It includes not only primary striate visual area, but also the parietal, temporal and prefrontal corticies. The new data was obtained about the participation of structures, responsible for navigation (parahippocampal gyrus and entorhinal area) in the line orientation detection. For the first time the gender-related differences in the organization ofthe line detection network were described. The obtained data provides a significant supplement to the knowledge of the mechanisms of the orientation sensitivity and assumes that orientation sensitivity plays an important role in the navigation.


Subject(s)
Brain Mapping , Evoked Potentials/physiology , Orientation/physiology , Visual Cortex/physiology , Adult , Electroencephalography , Female , Humans , Male , Visual Perception/physiology
8.
Prikl Biokhim Mikrobiol ; 50(1): 85-94, 2014.
Article in Russian | MEDLINE | ID: mdl-25272757

ABSTRACT

The biological activity of lipids and photosynthetic pigments of the kelp Sargassum pallidum (Turner) C. Agardh has been studied. Free fatty acids and their esters demonstrated considerable antimicrobial activity against bacteria (Staphylococcus aureus[ital] and Escherichia coli), yeast-like fungi (Candida albicans), and opportunistic pathogenic (Aspergilius niger) and phytopathogenic (Fusarium oxysporum, and Septoria glycines) fungi. Glyceroglycolipids and neutral lipids demonstrated moderate activity. Fucoxanthin and chlorophylls weakly suppressed the growth of microorganisms. None of the studied substances demonstrated activity against Ehrlich's carcinoma. It was shown that the season of weed harvesting affected both antimicrobial and hemolytic activities of different lipids due to changes in their fatty acid composition.


Subject(s)
Anti-Infective Agents/pharmacology , Fatty Acids, Nonesterified/pharmacology , Fatty Acids/pharmacology , Pigments, Biological/pharmacology , Sargassum/chemistry , Animals , Anti-Infective Agents/isolation & purification , Candida albicans/drug effects , Candida albicans/growth & development , Carcinoma, Ehrlich Tumor/pathology , Cell Survival/drug effects , Chlorophyll/isolation & purification , Chlorophyll/pharmacology , Erythrocytes/drug effects , Escherichia coli/drug effects , Escherichia coli/growth & development , Fatty Acids/isolation & purification , Fatty Acids, Nonesterified/isolation & purification , Fusarium/drug effects , Fusarium/growth & development , Glycolipids/isolation & purification , Glycolipids/pharmacology , Mice , Photosynthesis/physiology , Pigments, Biological/isolation & purification , Seasons , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Tumor Cells, Cultured , Xanthophylls/isolation & purification , Xanthophylls/pharmacology
9.
Fiziol Cheloveka ; 40(6): 88-97, 2014.
Article in Russian | MEDLINE | ID: mdl-25711112

ABSTRACT

Orientation sensitivity in human visual system was investigated in three experiments. In the first experiment 134 subjects were to determine the orientation of the segments of short lines, by "selecting" it from a set of reference orientations (Benton's test). In the second experiment 41 subject, which was chosen from participants of the first experiment, were to estimate the proximity of oblique lines to the vertical, horizontal, and 45° axis. In the third experiment participants were to identify the orientation of cardinal (0° and 90°) and oblique (45° and 135°) lines. It was shown that the cardinal orientations were defined more accurately and faster than the oblique ones. Error type depended on experimental conditions: participant answers tilted to horizontal under normal illumination in the presence of peripheral visual information, but they tilted to vertical under low illumination (3 lux.). Women performed worse only those tasks which require precise determination of the line orientation. It was assumed that the metric spatial characteristics determined better by males then females. The oblique effect was more pronounced in females, presumably due to gender differences in brain organization of the multimodal reference frame.


Subject(s)
Orientation/physiology , Sex Characteristics , Space Perception/physiology , Task Performance and Analysis , Visual Perception/physiology , Adult , Female , Humans , Male , Photic Stimulation , Young Adult
10.
Fiziol Cheloveka ; 40(4): 5-17, 2014.
Article in Russian | MEDLINE | ID: mdl-25707214

ABSTRACT

In psychophysical (n = 55) and neurophysiological (n = 25) experiments subjects recognized the images from two categories--"animals" and "non-living objects" under forward masking. Subjects recognized images in two experimental conditions: the target and masking stimuli (SOA = 50 ms) belonged to same category and the stimuli belonged to different categories ("compatible" or "incompatible" pairs). It was found that an efficiency of forward masking depends on the categorical proximity the mask and the target stimuli. The probability of correct answers was lower, and reaction time and it's dispersion were higher in "compatible" situation as compared with the "incompatible" one. The worsening of behavioral response in "compatible" condition was associated with decreased amplitude of N2 and P3 components of ERPs. The observed effects appeared to be more marked in animal recognition in comparison with object recognition. The results are discussed in the context of negative priming and an influence of distractor.


Subject(s)
Cognition/physiology , Electroencephalography , Visual Perception/physiology , Adult , Evoked Potentials , Female , Humans , Male , Photic Stimulation , Reaction Time
11.
Fiziol Cheloveka ; 39(3): 26-34, 2013.
Article in Russian | MEDLINE | ID: mdl-23885550

ABSTRACT

In 34 healthy subjects we have analyzed accuracy and reaction time (RT) during the recognition of complex visual images: pictures of animals and non-living objects. The target stimuli were preceded by brief presentation of masking non-target ones, which represented drawings of emotional (angry, fearful, happy) or neutral faces. We have revealed that in contrast to accuracy the RT depended on the emotional expression of the preceding faces. RT was significantly shorter if the target objects were paired with the angry and fearful faces as compared with the happy and neutral ones. These effects depended on the category of the target stimulus and were more prominent for objects than for animals. Further, the emotional faces' effects were determined by emotional and communication personality traits (defined by Cattell's Questionnaire) and were clearer defined in more sensitive, anxious and pessimistic introverts. The data are important for understanding the mechanisms of human visual behavior determination by non-consciously processing of emotional information.


Subject(s)
Emotions/physiology , Face , Visual Perception/physiology , Adult , Female , Humans , Male
12.
Article in Russian | MEDLINE | ID: mdl-25464744

ABSTRACT

In 38 healthy subjects accuracy and response time were examined during recognition of two categories of images--animals andnonliving objects--under forward masking. We revealed new data that masking effects depended of categorical similarity of target and masking stimuli. The recognition accuracy was the lowest and the response time was the most slow, when the target and masking stimuli belongs to the same category, that was combined with high dispersion of response times. The revealed effects were more clear in the task of animal recognition in comparison with the recognition of nonliving objects. We supposed that the revealed effects connected with interference between cortical representations of the target and masking stimuli and discussed our results in context of cortical interference and negative priming.


Subject(s)
Pattern Recognition, Visual/physiology , Perceptual Masking/physiology , Reaction Time/physiology , Adult , Female , Humans , Male , Photic Stimulation , Recognition, Psychology
13.
Fiziol Cheloveka ; 38(3): 18-29, 2012.
Article in Russian | MEDLINE | ID: mdl-22830240

ABSTRACT

In 16 men and 15 women analyzed the accuracy, reaction time and visual evoked potentials during the recognition of familiar objects at different levels of spatial transformation. We used the three levels of transformation: in a fixed position relative to each other details were carried out (1) the displacement of all the details in the radial direction and (2 and 3) a similar shift in conjunction with the rotation of all the details of the figure by +/- 0-45 and +/- 45-90 degrees. The task performance was not dependent on gender: the transformation of the image led to a deterioration of identification with the most identification impairment in the case of maximal details' rotation. Changes in evoked potentials (ERP) are different for men and women. Only in men early (100 ms after stimulus) response of the parietal cortex associated with the level of figure transformation: the more rotation evoked the higher the response. In women figure transformation evoked the ERP changes in the time window of negativity N170, they are associated with figure ungrouping but not with details rotation, and are localized in other visual areas--occipital and temporal. The data obtained are discussed in light of theory of gender specificity of the visual representations of space.


Subject(s)
Evoked Potentials, Visual/physiology , Parietal Lobe/physiology , Pattern Recognition, Visual , Sex Factors , Adult , Brain Mapping , Electroencephalography , Female , Humans , Male , Pattern Recognition, Visual/physiology , Reaction Time/physiology
14.
Neurosci Lett ; 524(2): 74-8, 2012 Aug 30.
Article in English | MEDLINE | ID: mdl-22801251

ABSTRACT

The gender differences in accuracy, reaction time (RT) and amplitude of the early P1 and N1 components of ERPs during recognition of previously memorized objects after their spatial transformation were examined. We used three levels of the spatial transformation: a displacement of object details in radial direction, and a displacement in combination with rotation of the details by ±0° to 45° and ±45° to 90°. The accuracy and the RT data showed a similarity of task performance in males and females. The effect of rotation was significantly greater than the effect of simple displacement, and the accuracy decreased, and the RT increased with the rotation angle in both genders. At the same time we found significant sex differences in the early stage of visual processing. In males the P1 peak amplitude at the P3/P4 sites increased significantly during the recognition of spatially transformed objects, and the wider the angle of rotation the greater the P1 peak amplitude. In contrast, in females the P1 peak amplitude did not depend on the rotation of figure details. The N1 amplitude revealed no gender differences, although the object transformation evoked somewhat greater changes in the N1 at the O1/O2 sites in females compared to males. This new fact that only males demonstrated the sensitivity of early perceptual stage to the transformation of objects adds information about the neurobiological basis of different strategies in the visual processing used by each gender.


Subject(s)
Evoked Potentials, Visual , Form Perception , Psychomotor Performance , Recognition, Psychology , Adult , Electroencephalography , Female , Humans , Male , Photic Stimulation , Rotation , Sex Factors , Young Adult
15.
Rev Sci Instrum ; 83(2): 02B913, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22380345

ABSTRACT

At the ion source test bench in Institute for Theoretical and Experimental Physics the program of ion source development for semiconductor industry is in progress. In framework of the program the Metal Vapor Vacuum Arc ion source for germanium and rhenium ion beam generation was developed and investigated. It was shown that at special conditions of ion beam implantation it is possible to fabricate not only homogenous layers of rhenium silicides solid solutions but also clusters of this compound with properties of quantum dots. At the present moment the compound is very interesting for semiconductor industry, especially for nanoelectronics and nanophotonics, but there is no very developed technology for production of nanostructures (for example quantum sized structures) with required parameters. The results of materials synthesis and exploration are presented.

16.
Ross Fiziol Zh Im I M Sechenova ; 98(11): 1339-49, 2012 Nov.
Article in Russian | MEDLINE | ID: mdl-23431764

ABSTRACT

In 31 subjects (16 men and 15 women) in model of the gender differences the brain mechanisms of two different strategies of visual-spatial tasks performance were studied. Although we did not find gender differences in the performing of visual-construction task the pattern of evoked activity was unequal in men and women. In men the early answer of the parietal cortex was related with spatial transformation of figure: the more was rotation of figures details, the more was amplitude of P1 wave. Moreover the amplitude of P1 wave in parietal area decreased with incorrect answers. In opposite, in women we did not find any ERP changes reflecting the details rotation. At the same time, in women we observed the increase of N150 negativity in occipital and infero-temporal cortex area when figure ungrouped into separate details. Our results shed light on some additional information concerning the basis of gender differences in performing of visuo-spatial tasks. Our data show that different strategies are not only defined by the later, but also the early stages of visual processing.


Subject(s)
Decision Making/physiology , Parietal Lobe/physiology , Sex Characteristics , Task Performance and Analysis , Visual Perception/physiology , Evoked Potentials/physiology , Female , Humans , Male
18.
Prikl Biokhim Mikrobiol ; 46(4): 467-71, 2010.
Article in Russian | MEDLINE | ID: mdl-20873173

ABSTRACT

Antimicrobial and hemolytic activity of ethanol extract of brown seaweed Laminaria cichorioides Miyabe, its lipophilic fractions, various classes of substances of lipophilic fraction, such as chlorophylls, fucoxanthin, monogalactosyldiacylglycerols, digalactosyldiacylglycerols, sulfoquinovosyldiacylglycerols, and fatty acids were investigated. The antimicrobial activity was studied by means of yeast cells Safale S-04 and Candida albicans CMM 455, fungi Aspergillus niger CMM 4634 and Fusarium oxysporum CMM 4639, bacteria Staphylococcus aureus ATCC 21027 (gram-positive) and Escherichia coli ATCC 15034 (gram-negative) which demonstrated selective sensitivity to the studied substances. Hemolytic activity was investigated at concentrations of substances in the range of 0.2-2000 microg/ml at different pH of erythrocyte suspension. All investigated substances caused hemolysis. The dependence of hemolytic activity of substances on pH of media was determined.


Subject(s)
Anti-Infective Agents/pharmacology , Hemolytic Agents/pharmacology , Laminaria/chemistry , Animals , Anti-Infective Agents/isolation & purification , Aspergillus niger/drug effects , Candida albicans/drug effects , Erythrocytes/drug effects , Escherichia coli/drug effects , Fusarium/drug effects , Hemolysis , Hemolytic Agents/isolation & purification , Mice , Staphylococcus aureus/drug effects
19.
Rev Sci Instrum ; 81(2): 02B905, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20192471

ABSTRACT

The rhenium silicides are very attractive materials for semiconductor industry. In the Institute for Theoretical and Experimental Physics (ITEP) at the ion source test bench the research program of rhenium silicide production by ion beam implantation are going on. The investigation of silicon wafer after implantation of rhenium ion beam with different energy and with different total dose were carried out by secondary ions mass spectrometry, energy-dispersive x-ray microanalysis, and x-ray diffraction analysis. The first promising results of rhenium silicide film production by high intensity ion beam implantation are presented.

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