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The mechanism of Ukhtomskiĭ's dominant was used to improve operator's performance activity. Recognition of visual images--obscured Arabic numerals--in a sensorially rich environment (classic or rock music records) turned to be more successful: time of the task was reduced and the probability of correct identification increased. A reverse U-shaped dependence between the intensity of music and identification was stated. Repetition of music fragments at a constant value marred the positive effect.

In a search for modifiers of gene expression with the white eye color gene as a target, a third chromosomal P-element insertion mutant l(3)01544 has been identified that exhibits a strong pigment increase in a white-apricot background. Molecular analysis shows that the P-element insertion is found in the first intron of the gene surrounding the insertion site. Sequencing both the cDNA and genomic fragments revealed that the identified gene is identical to one encoding ribosomal protein P0/apurinic/apyrimidinic endonuclease. The P-element-induced mutation, l(3)01544, affects the steady-state level of white transcripts and transcripts of some other genes. In addition, l(3)01544 suppresses the variegated phenotypes of In(1)wm4h and In(1)y3P, suggesting a potential involvement of the P0 protein in modifying position effect variegation. The revertant generated by the precise excision of the P element has lost all mutant phenotypes. Recent work revealed that Drosophila ribosomal protein P0 contains an apurinic/apyrimidinic endonuclease activity. Our results suggest that this multifunctional protein is also involved in regulation of gene expression in Drosophila.

Time of recognition by human subjects of masked Arabic numerals decreased and the probability of correct responses increased under conditions of listening of tape-recordings of classic or rock music. Changes in recognition were most pronounced under the definite music power. The efficiency of recognition decreased during repeated listening of the same music fragments with unchanged power. The obtained data are considered as a manifestation of the dominant regularities.

A mutation in Regena (Rga) was isolated in screens for modifiers of white eye color gene expression. The reduction in the level of the Rga product results in a complex modulation of white mRNA both positively and negatively, depending on the developmental stage. In addition to white, Rga also affects the expression of several other tested genes, with one of them, Vinculin, being regulated in a strong sex-specific manner. Rga was cloned by transposon tagging. Its predicted product lacks any recognized nucleic acid-binding motif but is homologous to a global negative transcriptional regulator, CDC36 (NOT2), from yeast. Rga also acts as a suppressor of position effect variegation, suggesting that a possible function of Rga could be mediation of an interaction between chromatin proteins and the transcriptional complex.

An African student developed bilateral relapsing iridocyclitis with increased intraocular pressure. General examinations and parasitological studies revealed tropical malaria. Etiotropic and local therapy normalized intraocular pressure and improved vision acuity of both eyes. This case should be borne in mind by general practitioners as a possibility of transportation of various tropical diseases.

Problems in complex surgical treatment of myopia are discussed. Extensive clinical data and long follow-up of the patients permitted the authors to develop a well-based system of care which helps not only arrest the progress of myopia, but correct it within a rather wide range. The pathogenesis of tissue process in progressive myopia is discussed basing on the regularities revealed experimentally. The main modern operations on the cornea and sclera are described. Data on the inter-layer transplantation of the cornea, developed at the Chair of Ophthalmic Diseases of the Russian University of Peoples' Friendship are presented.

A new original method of interlamellar sectorial keratoplasty is proposed for surgical correction of astigmatism. Eleven operations were carried out in 8 patients (11 eyes) with astigmatism of 4 to 7.0 diopters. Vision acuity without correction was 0.6 to 1.0 in 5 patients (7 eyes, 63.6%). In 2 patients (2 eyes, 18.2%) vision acuity without correction was 0.3 to 0.5 diopters, and in 2 more patients (2 eyes, 18.2%) it was from 0.1 to 0.3 diopters, that is, equal to the maximal vision acuity with the optimal correction. The refraction effect stabilized in 3-4 months. The highest refraction effect attained was 7.0 diopters. The patients were followed up for 3 months to 4 years. Clinical analysis of the operations confirmed the efficacy and reliability of the method and stability of refraction. Interlamellar sectorial keratoplasty is recommended for surgical correction of astigmatism.

A case with toxocariasis of the eye is described. The diagnosis was confirmed serologically. Vision acuity improved to 100% as a result of treatment. The authors emphasize that toxocariasis should ruled out in all ocular involvements of obscure etiology.

A new method is proposed for the correction of high myopia: Interlamellar circular keratoplasty. This method has been used in 15 patients (17 eyes) aged 18 to 54 with 9 to 17 diopters myopia. Vision acuity attained was at least 0.5 in 10 (60.3%) patients; in 7 (35.2%) patients vision acuity was 0.3 without correction, that is, was equal to the maximal vision acuity with the optimal correction. The highest refraction effect was 15.0 diopters. The patients were followed up for 3 months to 16 years. The proposed method for the correction of high myopia is highly effective, simple, and is recommended for clinical practice.

A new cytochrome P450 gene was found within the wap1-prune genetic region of the Drosophila melanogaster X chromosome. It encodes a putative cytochrome P450 of subfamily 4D and has been designated CYP4D2. CYP4D2 has a complex exon-intron structure. Both the heme-binding motif and a region diagnostic for family 4 are not interrupted by introns. CYP4D2 lies 20 kb proximal to the previously described CYP4D1 gene (Gandhi et al., 1992). In addition to CYP4D1 and CYP4D2, two other DNA fragments homologous to P450 genes are detected within the wap1-prune region.

A full-length 1.8 kb cDNA of the Drosophila melanogaster gene prune together with the corresponding genomic sequence was cloned and sequenced. Comparison of the two sequences revealed the existence of the intron in the prune primary transcript. The putative prune protein is likely to have a single transmembrane domain. The nature of several prune mutant alleles was analysed: the size and quantity of prune mRNA were found to be decreased in pn1 and pn3 mutations. Mutations pn1 and pn54c were shown to be accompanied by insertions of the same novel mobile repeated element.

Using Northern analysis three transcription areas are detected in the gene prune region from which three different mRNAs 1.8, 1.75 and 1.0 kb in length transcribe. Corresponded cDNAs are cloned. Only 1.8 kb mRNA is shown to be changed in size and quantity in the case of the pn1 and pn3 mutations. This mRNA seems to be a gene prune transcript. From the analysis of the portion of cDNA c1.1 nucleotide sequence corresponded 1.75 kb mRNA follows that its putative amino acid product contains a heme-binding site which is characterized for P450 cytochrome superfamily. On the basis of presented results and published data by Teng et al [1] it may be concluded that at least five different mRNAs transcribe in the gene prune region in area spanning about 10 kb.

Analysis of transcription of the gene prune being undergone position effect variegation in the inversion In(1LR)pn2a is presented. Using Northern hydridization with following densitometric analysis of blots it was shown that the quantity of the prune mRNA is decreased 1.8 +/- 0.4 times in comparison with normal. Transcripts differing from wild type sizes are not detected. On the basis of the results obtained of inactivation propagation in the case of the position effect.

Modified states of consciousness are created under the conditions of monotony with modulating influences in minute wave length diapason. These data point to an important role of the modulating system of the cerebral brain in consciousness the content of which is determined by informational processes.

Application of contactless control method does not create any psychological or physical discomfort for a man and allows to realize diagnostics continuously for a long time, evidently or secretly. These properties of the control determine its effective application in practice. In the paper the data are given of the studies of the functional state of a man-operator using the parameters of the eyelids movements contactlessly recorded in infra-red rays, and the results of diagnostics of patients with depression by the characteristics of their speech, recorded from the microphone. The above data are obtained in practice.

This article examines the development of the visual-motor skill of pursuit tracking. Parameters studied include tracking error and emotional tension, as manifested in heart rate and strength of grip exerted on the control handle used in the task. A specially developed device converted grip strength into an electrical signal suitable for analysis. Grip strength proved to be a more sensitive indicator of development and level of skill than traditionally used parameters of tracking error stabilization and minimization of emotional-autonomic shifts. Computation of the ratio of grip strength to tracking error makes it possible to estimate the "physiological cost" and, thus, reliability of operator performance. The device for registering grip strength is incorporated into the control system and may be used in systems providing continuous diagnostic information without interfering with operator performance.

At comparison of the formation of neurosis in dogs with different typological characteristics in conditions with alimentary and pain reinforcement, a resemblance was revealed of transition from norm to the initial stage of pathology. In strong animals a development was seen of compensatory tachycardia at circular changes of conditioned activity. Weak type dogs are characterized by a lowering or full disappearance of reflexes in combination with bradycardia. The method of differentiation, allowing in situations with alimentary reinforcement to classify the tested animals according to the type of higher nervous activity and differentiate the states of "norm" and "initial stage of neurosis", proved to be effective for the analogous aims also in studies with defensive reinforcement.

The level of emotional stress depending on the power of motivation and the estimation by the subject of the probability (possibility) of goal achievement, largely influences the operator's skill performance (that of a pilot, controller, astronaut). A decrease in the emotional tonus leads to drowsiness, lack of vigilance, missing of significant signals, and to slower reactions. The extremely high stress level disorganizes the activity, complicates it with a trend toward untimely acts and reactions to the insignificant signals (false alarms). The best methods to monitor the degree of the operator's emotional state during his skill performance are the integral estimation of the changes in heart-rate and T-peak amplitude, as well as the analysis of spectral and intonational characteristics of the human voice during radio conversation. These methods were tested on paratroopers, pilots in civil aviation, and airport controllers.

An improved method of discerning emotional colouring of speech on the frequency of main tone and average number of intersections at zero level within the range of first formant frequencies is described. Vowels from words pronounced by announcers in different emotional states served as material for experiments. The method elaborated in the experiments with actors and drama school undergraduates was then tested in natural conditions on amateur parachute jumpers.

The method of mathematical forecasting of the changes in efficiency throughout an increase in emotional stress is suggested on the basis of experimental data from experiments in which paratroopers discerned visual patterns. The comparison of human errors with the experimental results obtained in animals permitted formulation of several suppositions on the role of different cerebral structures in the genesis of emotional stress and the mechanisms of its effect on perceptive activity.

The object of the study was to observe the changes in efficiency of perceptive activity of man (recognition of visual patterns against a background of noises) throughout an increase in emotional stress caused by a forthcoming parachuete jump. A moderate degree of emotional stress can improve performance efficiency and decrease the number of the subject's errors. Later an impairment of differentation of similar signals was seen and an increase in the number of "false alarm" errors along with a decrease in the number of omissions to reactions signals. The neurophysiological basis of such changes in perceptive activity consists in a transition from conditional behaviour to reaction through mechanisms of Ukhtomsky's dominant focus.

In the initial period of neurosis, significant differences were found in changes of motor and vegetative reactions in dogs of dissimilar typology. Animals with strong type of the nervous system displayed cyclic transitions from the normal state to the initial stage of pathology and vice versa. Such transitions were practically absent in dogs of the weak type. A method is proposed providing efficient classification of experimental dogs according to their types of higher nervous activity and differentiation of the normal state and the initial stage of neurosis.

Infralow oscillations were studied of psychophysiological parameters appearing at one-minute wave range at different levels of human operator's nervous system in conditions of monotony. In experiments on recognition of noisy visual images presented with the frequency of 6-9 signals per hour, 22 subjects took part. The following was found: a) correlation between superslow components of pulse rate and the coefficient of brain potentials synchronization, established in 20-30 min after the beginning of the experiment; b) a tendency to deterioration of the quality of recognition at the stages of slowing down of infralow waves of the pulse rate and to its improvement at the phases of the increase of their frequency. Main results were obtained by the method which needs neither unartifact electrodes nor DC amplifiers. Possible mechanisms of stated dependences are discussed.

Background factors and those of formant structure, spectral and spectro-temporal characteristics of rapid and slow speech components, temporal peculiarities, and intensity of speech turned out to be informative indices of the human emotional state. Application of mathematical methods, in particular methods of recognition theory, to these factors helped to assess the degree and the psychological sign of emotion, to diagnose the status of attention and fatigue, and to differentiate emotional and physical stress. The paper outlines the results obtained in model experiments on cosmonaut A. Leonov at different flight stages, including EVA, on Voskhod-2.

Objective estimation of the human operator's functional state is an urgent problem in applied psychophysiology. It helps to forecast the reliability and efficiency of the operator's activity. Slow (minute) changes in the functional state of 22 subjects were recorded and analysed in experiments simulating the long-term operator's activity. Spatial synchronization of the electroencephalogram (EEG) and the heart-rate (HR) served as parameters. It was shown that the time of detection and identification of visual signals (geometrical figures) amid visual "noise" in a long-term observation naturally depends on the changes in a subject's state. These changes were estimated by slow (2-3 min) components of the changes in spatial synchronization of EEG and HR throughout 3 h of the experiment. These objective parameters of the human operator's state may be used to predict efficiency. The connection between minute oscillations of electrophysiological parameters and time of reaction is absent during the first 30 min of the experiment, then appears and increases throughout further stages, becoming clearly marked in its second half.

The changes in the length of interval R-R and in heart rate are widely used for estimation of man's physical state. How-ever, this ECG index has several drawbacks including a relatively low sensitivity and non-specificity, unindirection of changes under different states: attention and fatigue, physical and emotional stress, etc. Moreover, one and the same factor, e.g. emotional stress, can lead both to a decrease and an increase in the heart rate. Hence, it is necessary to find other more adquate ECG parameters, which would enhance the reliability and accuracy of assessment of man's state. The analysis of data found in literature and the results of our preliminary experiments have shown that the amplitude of the t-peak and duration of the R-T interval of ECG can be used as such parameters.

Eyelid movements (EM)--blinking frequency and duration of closed eyes--may serve as a parameter of fatigue in humans performing as operators. Twenty subjects were told to locate and follow visual signals appearing on a screen at the frequency of 4-5 X h-1 and moving in a background of bright noises. EM was recorded in infra-red rays with tiny sensors attached to glasses' rim. EEG and ECG were recorded simultaneously. It was found that a change in EM is a sensitive parameter of fatigue and better corresponds to decreased quality of performance (time of locating signal and error in following), than changes in R-R interval. In the second experimental series, symptoms of fatigue discovered by EM were accompanied by sound signals, which improved operator's performance by 15-20%. Recording of EM may be used to monitor operator's state in humans and to forecast reliability of performance.

According to the informational theory of emotions, emotions in humans depend on the power of some need (motivation) and the estimation by the subject of the probability (possibility) of the need satisfaction (the goal achievement). Low probability of need satisfaction leads to negative emotions, actively minimized by the subject. Increased probability of satisfaction, as compared to earlier forecast, generates positive emotions, which the subject tries to maximize, i.e. to enhance, to prolong, to repeat. The informational theory of emotions encompasses their reflective function, the laws of their appearance, the regulatory significance of emotions, and their role in organization of behavior. The level of emotional stress influences the operator's performance. A decrease in the emotional tonus leads to drowsiness, lack of vigilance, missing of significant signals and to slower reactions. An extremely high stress level disorganizes the activity, complicates it with a trend toward incorrect actions and reactions to insignificant signals (false alarms). The neurophysiological mechanisms of the influence of emotions on perceptual activity and operator performance as well as the significance of individuality are discussed.