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The effect of the stage of development of a malignant tumor on successful detection in the urine of animals with oncology by dogs was studied. It was demonstrated that the success of dogs in the search for sick organisms among healthy ones is quite consistent with the dynamics of the development of transplanted tumor tissue; that is, dogs are able to perceive both the entire spectrum of volatile metabolites accompanying the disease and changes in this spectrum associated directly with the development of the tumor. The existence of volatile organic compounds associated with the growth of a malignant tumor was established.

Recent studies have revealed how the freshwater biota of Lake Baikal responds to climate change and anthropogenic impacts. We studied phyto- and zooplankton, as well as phyto- and zoobenthos, in the open coastal waters of the southern basin of the lake and of Listvennichny Bay. A total of 180 aquatic organism taxa were recorded. The response of the Baikal ecosystem to climate change can be traced by changes in the species composition of planktonic communities of the lake’s open coasts in summer. The key species were thermophilic the Anabaena lemmermannii P. Richt. (Fij = +0.7) blue-green algae, the Asplanchna priodonta Gosse (Fij = +0.6) rotifers in 2016, the Rhodomonas pusilla (Bachm.) Javorn. (Fij = +0.5) cold-loving algae, and the Cyclops kolensis Lilljeborg (Fij = +0.9) copepods in the past century. The proportion of Chlorophyta decreased from 63% to 17%, the Cyanophyta increased from 3% to 11% in the total biomass of phytoplankton, and the proportion of Cladocera and Rotifera increased to 26% and 11% in the biomass of zooplankton, respectively. Human activity makes an additional contribution to the eutrophication of coastal waters. The Dinobryon species, the cosmopolitan A. formosa and F. radians, dominated phytoplankton, and filamentous algae, Spirogyra, dominated at the bottom in the area with anthropogenic impact. The trophic level was higher than at the unaffected background site: the saprobity index varied from 1.45 to 2.17, the ratio of eutrophic species to oligotrophic species ranged from 1:2 to 3:1, and the ratio of mesosaprobiont biomass to endemics biomass ranged from 2:1 to 7:1. Currently, the boundaries of eutrophication zones of shallow waters in Lake Baikal are expanding, and its coastal zone has acquired features typical of freshwater bodies of the eutrophic type.

Trained detection dogs distinguish between urine samples from healthy organisms and organisms with malignant tumors, suggesting that the volatile urine metabolome contains information about tumor progression. The aim of this study was to determine whether the stage of tumor growth affects the chemical differences in the urine of mice and to what extent the "olfactory image of disease" perceived by dogs coincides with the "image of disease" recorded by the mass spectrometer. We used a novel laser ionization mass spectrometry method and propose a mass spectrometric analysis without detailed interpretation of the spectrum of volatile metabolomes in urine. The mass spectrometer we use works without sample preparation and registers volatile organic compounds in air at room temperature without changing the pH of the sample, i.e. under conditions similar to those in which dogs solve the same problem. The experimental cancer models were male BDF-f1 hybrid mice transplanted with hepatocarcinoma tissue, and similar mice transplanted with healthy liver tissue were used as controls. Our data show that both dogs and our proposed laser mass spectrometry method are able to detect both the entire spectrum of volatile organic compounds associated with the disease and minor changes in this spectrum during its course.

A method of rapid mass spectrometric analysis of volatile organic compounds (VOC) of biological samples at atmospheric pressure has been developed. The method uses laser plasma radiation for ionization of VOC molecules. Multivariate statistics was used for the mass spectra analysis. The possibility of identification of progressing oncological process in mice with analyzing the composition of VOCs of the urine samples was showcased.

The freshwater ultraoligotrophic Lake Labynkyr is located near the Pole of Cold in the northern hemisphere (Yakutia, Russia). The lake is covered by ice during 240 days a year. We undertook several expeditions to the lake during the ice and open water periods for sampling ice fouling, plankton and periphyton that were then analyzed by means of scanning electron microscopy. As a result, we identified a high biodiversity of diatoms—123 species and intraspecific taxa from 53 genera, among them 3 species were new for Russia and 26 taxa were new for the algal flora of Yakutia. The oligo- and xenosaprobionts and their variations dominate—71 taxa. 18 Species were evaluated as tolerant to cold oligotrophic waters, 12 occurred on the ice bottom, and 62 in the water column under ice (0–25 m). 104 taxa were found during the open water period, 70 taxa were identified in the periphyton. We showed the diatom flora of Lake Labynkyr to be unique compared with other lakes of Yakutia and to share taxa with the diatom flora of Lake Baikal. The diatoms being indicators of the global climate changes and ecological status of lakes, our data can be used as an evidence of such changes as well as to be useful studies of biogeography and history of formation of flora in Arctic and Subarctic waters.

We have tested the original version of the University of Pennsylvania Smell Identification Test (UPSIT) on a population of Central Russia including groups of different ages residing in the city area and in the rural part of the country. Our results demonstrate that the UPSIT is applicable for evaluation of olfactory function within the population of Central Russia and allows us to detect age-related differences in olfactory function. However, several odor samples presented within the original UPSIT proved to be unfamiliar to the subjects due to cultural differences. We have identified and tested odor items that may replace poorly recognizable items of the original UPSIT. Thus, we have developed a culturally adapted version of the UPSIT to be used within the population of Central Russia.

We studied the effect of the peppermint ambient odor on the performance of routine Russian school language tests by primary-school students in a standard classroom, where a noiseless source of odor provided scenting the air by means of free evaporation of the essential oil at a constant low concentration. It is shown that in the presence of peppermint odor the marks for a word dictation test that is based on the longterm memory are significantly higher than in the absence of the odor, whereas the performance of text copying test (based mainly on attention) is not influenced by the presence of peppermint odor.

International audience; A scent lineup is generally a procedure whereby a dog's alerting behavior is used to establish that the dog detects two scents, one from a crime scene and one from a suspect, as deriving from the same person. The aim of this article is to compare methodologies of using dogs in scent lineups as a means of identifying perpetrators of crimes. It is hoped that this comparative approach, looking at countries where the method is currently or has in the past been used, will help determine what issues should be addressed in order to assure that the scent lineup will have a future as a forensic technique. Participants from eleven countries-Belgium, The Czech Republic, Finland, France, Germany, Hungary, Lithuania, The Netherlands, Poland, Russia, and the U.S.-completed a survey questionnaire regarding key aspects of the scent lineup procedures used by the police in their countries. Although there was broad overlap on certain matters, such as the use of control and zero trials, collection of decoy scents from individuals of similar gender and race as the suspect, materials for holding scent, frequency of cleaning and changing stations, and use and timing of rewards, there were significant differences in the degree of blindness required, who calls an alert (handler or experimenter), and whether handlers can work with more than one dog. The gap between recommendations and results available from the scientific literature and procedures used in police practice was greater for some countries than others, even taking into account that some scientific methodologies might be expensive or impractical given agency resources. The authors make recommendations about how to go forward if scent lineups are to remain a valid forensic technique.

No standardized test is currently used in research or clinical practice in Russia, a country with a total population of ~150 million people. To close this gap, we have tested the original version of the University of Pennsylvania Smell Identification Test (UPSIT) on the population of central Russia including groups of different ages residing in urban areas and in the rural part of the country. Our results demonstrate that the UPSIT is applicable for the evaluation of olfactory function within the population of Central Russia, and allows the detection of age-related differences in human olfactory function. However, several odor samples present within the original UPSIT proved to be unfamiliar to the subjects due to cultural differences. We have therefore tested and identified odor items that may replace poorly recognizable smells of the original UPSIT. Thus, we have developed a culturally adapted version of the UPSIT to be used within the population of the Central Russia.

Macrosmatic animals (dogs and mice) have been proved to be able to distinguish between the urine or feces of mice with transplanted hepatocellular carcinoma and those of healthy mice by odor. The chemical composition of animal excreta was found to change with tumor growth; however, it is not clear yet if this results from tumor growth itself, inflammation, or immune response. We suggested that the use of the ability of macrosmatic animals to compare odor mixtures combined with mouse cancer models is a promising trend in the search for new tumor markers.

Macrosmatic animals (dogs and mice) have been proved to be able to distinguish between the urine or feces of mice with transplanted hepatocellular carcinoma and those of healthy mice by odor. The chemical composition of animal excreta was found to change with tumor growth; however, it is not clear yet if this results from tumor growth itself, inflammation, or immune response. We suggested that the use of the ability of macrosmatic animals to compare odor mixtures combined with mouse cancer models is a promising trend in the search for new tumor markers.

Neuronal response in the caudate nucleus to presentation of a wide variety of visual and other sensory stimuli was investigated in waking cats. Pronounced discrepancies in background activity of unknown origin as well as differing neuronal activity level were noted in adjacent sections of the nucleus. Of the neurons from which readings of response to sensory stimulation could be made, some reacted to presentation of exclusively visual and others to tactile stimuli; a third group responded to a combination of visual and somatic stimulation only. Response could only be produced in cells of all types by a high level of activity in the animal. Visual stimuli attracting the animal's interest proved to be the most effective form of stimulation. Ipsi- and contralateral sides of the animal's body were both represented in the caudate nucleus of each hemisphere. Neuronal response in the caudate nucleus may be compared with that produced by application of similar stimuli in cells belonging to different cortical areas.

The effects of applying electromicrostimulation to areas of the caudate nucleus with different neuronal activity patterns were investigated during chronic experiments on four cats. Caudate sites containing neurons responding to presentation of various sensory stimuli were selected for the first set of experiments and those where no neuronal activity manifested in the second series. Histological verification of electrolytic marker sites produced by electrical stimulation took place at the end of each experimental sequence and the cell types surrounding these lesions were examined. Microelectrostimulation consistently produced movement in the animal in the first set of experiments; markers were located along the surface of striosomes among large-sized cells, bundles of fibers, and blood vessels. In the second, electrical stimulation produced no alteration in naturally occurring animal behavior; markers were located within striosomes in accumulations of small- and medium-sized cells. A survey of the findings obtained would confirm our hypothesis that the neurons from which activity had been recorded by extracellular techniques in the caudate nucleus are large-sized cells with long axons.

The distribution of neurons responding to presentation of different sensory stimuli was investigated during chronic experiments on cats. These showed that cells responding to somatic and visual stimulation were unevenly distributed and that areas with differing levels of activity within the same nucleus alternated. No single topic projection was identified within the structure reaching the entire nucleus. The findings were compared with those found during morphological research indicating heterogeneity in caudate nucleus structure, implying the existence of neuronal groupings (or striosomes) belonging to a topically organized projection from the animal's body.

Recently, elongated comet-shaped receptive fields were discovered in the fourth extrastriate crescent (area V4A) of cats and monkeys. It was shown that the long axes of these receptive fields were oriented radially toward the centre of the retina. Such unusual "radial" organization of this extrastriate area led to the assumption that these neurons may contribute to the analysis of optic flow. To investigate this assumption we recorded activity of neurons in the V4A of cats during real motion in depth toward or away from a stationary visual scene. Responses of neurons in area V4A were compared with activity of neurons in area V2 under similar conditions of stimulation. Area V2 is known to be sensitive to motion but does not have radial organization. It was found that a substantial number of visual neurons in both areas did not fire at all when cats were exposed to motion in depth. Nevertheless, neurons with selective activation to direction of motion in depth were identified, but comparable numbers were found in both areas studied. We conclude that radial organization of the fourth extrastriate crescent does not provide any special advantage for the analysis of optic flow information.

In our previous study of the cytoarchitectonic field 7 of cat cortex we had described neurons with extremely elongated receptive fields (RFs). The long axes of these RFs were oriented radially, towards the centre of the retina. These neurons represented only the lower contralateral part of visual field. They were surrounded from all sides by neurons with clearly different RF properties. We proposed that neurons with a similar radial organization and with RFs in the upper visual field also exist in the cortex but are localized in the area that was distant from the representation of the corresponding lower visual field. We expected to find these neurons in front of the representation of the upper visual field in areas V1, V2 and V3 (fields 17, 18 and 19), behind the central representation in area 21a. This cortical region was studied in five behaving cats. In all animals, neurons with radial RFs in the upper visual field were found in the expected location. As in the lower visual field, their RFs always spared the central visual field. Other RF properties of these neurons were also very similar to those found previously in the lower visual field. It became obvious that neurons with radial RFs are included into the fourth extrastriate crescent with complete contralateral representation. However, in the fourth crescent, RF properties in the central visual field differed significantly from those on the periphery. As a result, neurons with similar radial RFs in the upper and lower visual fields were located in the distant cortical regions, and were separated by the representation of the central visual field presented by the non-radial neurons of the cytoarchitectonic area 21a.

It has been shown in chronic experiments that cells responding to somatic and visual stimuli are unevenly distributed in the caudate nucleus of a cat and areas of high and low activity alternate. Representational maps of somatic and visual space in the caudate nucleus are not single. These data as well as those on the morphological heterogeneity of the caudate nucleus suggest the presence of multiple somato- and retinotopic maps projecting independently on striosome surfaces.

Effects of electrostimulation of the caudate nucleus in cats were studied in chronic experiments. Position of electrolytic lesions resulting from stimulation was examined histologically with respect to the surrounding cell type. Stimulation of the caudate nucleus zones with cells responding to sensory stimuli induced cat's movement and corresponding lesions were situated around striosomes among large cells with long axons. Stimulation of "silent" zones (where we failed to record any neuronal activity) did not modify cat's behaviour, corresponding lesions were found inside striosomes in clusters of small and medium-size cells. Results obtained from this study confirm the previous conclusion that neurons which activity was recorded extracellularly in the caudate nucleus belong to large long-axon cells.

Responses of caudate neurons to a large variety of visual and other sensory stimuli were studied in alert cats. Sharp drops in the spontaneous activity of the unknown origin and differences in the activity level were revealed in adjacent parts of the caudate nucleus. The following types of neurons were recorded: neurons responding to visual stimulation; neurons responding to somatic stimulation; neurons responding to combined visual-somatic stimulation. The best response was observed to moving visual stimuli that attracted the animal's attention, alimentary objects specifically. The caudate nucleus of each hemisphere contained representation of both contra- and ipsilateral half of the animal body. Cell responses to sensory stimuli from the caudate nucleus have been compared with those from some cortical areas.

It has been shown by a number of investigators that perceived binocular direction (BD) could be changed by varying the contrast ratio between the left and right images of a target. In this and certain other cases, the former simple idea that BD is the average of the two monocular directions (MD) fails to predict BD correctly. As an alternative, Mansfield and Legge (1996 Vision Research36 27 – 41) suggested that a weighted average of modified MD signals be calculated with weights depending on respective image contrasts. However, in experiments including not only ordinary (monocularly recognisable) but also cyclopean (monocularly imperceptible) targets, we have found that there exist (at least) two principally different mechanisms responsible for calculation of BD and that one of these mechanisms is contrast-dependent while the other one is contrast-independent (Rozhkova et al, 1995 Sensory Systems9 46 – 57). The first one probably corresponds to the model of Mansfield and Legge but the second one (which determines perception of cyclopean targets) has other specific properties. In a new series of experiments based on the same paradigm (to align a test target with a control one under conditions of varying interocular contrast ratios for the test stimuli), we have found that perceived direction of a cyclopean target (coded by Julesz's random-dot stereogram) could be manipulated by memory. It appeared that if, in a given series of measurements, the random-dot patterns for the test targets were chosen at random from six samples, the results were independent of the contrast ratio, but if one and the same random-dot pattern was used many times throughout all the series of measurements, and the subject could memorise the texture of the target, perceived direction became dependent on contrast ratio as in the case of monocularly recognisable targets. One of the possible explanations of this effect is the secondary activation of the first BD mechanism, which usually does not process cyclopean targets.

Neurons responding to tactile and visual stimulation have been found in alert behaving cats in the caudal part of the ventral bank of cruciate sulcus. Tactile receptive fields were located on the cat face mainly around the mouth. Visual stimuli (especially alimentary ones) were effective being presented near the tactile receptive field. It was found that these bimodal neurons (visual and somatosensory) are located in layer VI of the cortex and their visual responses demonstrate space constancy. The position of the visual receptive field of these neurons did not change after saccadic eyes displacements, but remained in-register with the tactile receptive field.

Two types of reactions are produced in testing the sensitivity of tuberculous guinea pigs to tuberculin-either erythematous or hemorrhagic.

It was established that dimedrol averted the development of Shwartzman's phenomenon in rabbits when administered intracutaneously as follows: 1) simultaneously with the preparatcry dose of filtrate ofB. coli, 2) simultaneously with the resolving dose of filtrate ofB. coli and 3) one hour after the administration of the resolving dose of filtrate ofB. coli. Dimedrol did not avert the phenomenon in viscera.