[Electrical activity and circulatory effects of nitrite in the rat cerebrum].

An association between the cerebrum electrical activity (CEA) in rats, blood supply of its cortex microregions (linear blood flow), and general cerebrum blood flow under acute nitrite hypoxia was studied. The phase character of the change in hemodynamic indices and the total capacity of electroencephalography (EEG) spectrum for 75 min after sodium nitrite introduction (30 mg/kg of body weight) was detected. The first phase (30 min) was associated with cerebrum adaptation to hypotension caused by nitrite and was completed by EEG normalization. The second phase was characterized by pathological EEG changes (in spite of restoration of hemodynamics in the cerebrum) caused by the growth of oxygen debt in the nervous tissue as a result of a decrease in the blood oxygen capacity by 60-75 min of the effect of nitrite.

[Social and psychological motives of frequency of calls for emergency care in advanced age].

The purpose of this investigation relates to the problem encountered by the elderly population. There is a current increase of the number of elderly people and the share of the elderly population in many countries of the world. Living on their own, people of advanced age create specific problems, both medically and socially. The current investigation presents the data showing their high and "ultrahigh" appliance for the emergency, which not always is a reflection of the level of a disease. Request for the emergency of this social category of the population is ten times higher than in other age groups. As a result, it causes unnecessary economical expenses and requires a correction of social programs.

[The encephalogram in women during pregnancy and in the postpartum period].

The EEG registration during gestation and after delivery in fifteen women was done. The EEG analysis has shown the alpha-rhythm amplitude and frequency fluctuation during pregnancy and maximum of power spectra in third trimester. After delivery, a general decrease in alpha rhythm was observed. In addition, general decay of the brain functional state occurred which was manifested by paroxysmal activity in hyperventilation in some women. The results are discussed from the point of view of the central regulation of hormonal state in women during pregnancy and after deliver.

Fibonacci-like photonic structure for femtosecond pulse compression.

The compression of femtosecond laser pulses by linear quasiperiodic and periodic photonic multilayer structures is studied both experimentally and theoretically. We compare the compression performance of a Fibonacci and a periodic structure with similar total thickness and the same number of layers, and find the performance to be higher in the Fibonacci case, as predicted by numerical simulation. This compression enhancement takes place due to the larger group velocity dispersion at a defect resonance of the transmission spectrum of the Fibonacci structure. We demonstrate that the Fibonacci structure with the thickness of only 2.8 microm can compress a phase-modulated laser pulse by up to 30%. The possibility for compression of laser pulses with different characteristics in a single multilayer is explored. The operation of the compressor in the reflection regime has been modeled, and we show numerically that the reflected laser pulse is subjected to real compression: not only does its duration decrease but also its amplitude rises.

[A correlation of EEG characteristics of pregnant women with the level of their anxiety].

It has been shown that the EEG of pregnant women with high anxiety level is characterized by a lower occipital alpha and theta rhythm spectral power if compared to the EEG of women with low anxiety level. The frequency of the alpha rhythm of their EEG was reliably higher. Pregnant women with high anxiety level with a pregnancy interruption threat diagnosis have an essentially lower occipital alpha rhythm spectral power than women of this group without such a diagnosis. And vice versa, the occipital alpha rhythm spectral power in the EEG of pregnant women with low anxiety level with a pregnancy interruption threat diagnosis is essentially higher and its frequency essentially lower than the EEG of women without that diagnosis. The data received are interpreted as a change in hormone regulation during the pregnancy period, as well as psychogenic influence on the pregnancy.

[Changes in EEG induced by prolonged hyperventilation in humans]. / Kharakter izmenenii EEG cheloveka pri dlitel'noi giperventiliatsii.

The data obtained revealed a significant augmentation of the EEG slow-wave activity following a 32-minute hyperventilation in neurologically healthy subjects. In 43% of the subjects, on the 8th minute of the hyperventilation a generalised paroxysm of the delta-activity occurred.

[The significance of cytochemical studies of the metals in blood neutrophilic granulocytes in the diagnosis of lung diseases]. / Znachenie tsitokhimicheskikh issledovanii metallov v neitrofil'nykh granulotsitakh krovi pri diagnostike zabolevanii legkikh.

Peripheral blood smears from healthy persons and patients with pneumonia and pulmonary tuberculosis were used for a cytochemical study of metals in neutrophils with the help of dithisone and chlortetracycline. The content of metals in these cells was increased in pneumonia and active tuberculosis, but was normal or decreased in non-active pulmonary tuberculosis. It is concluded that cytochemical reactions for metals may be used in the diagnosis of pulmonary diseases.

[The assessment of the subjective second by using the "individual minute" test]. / Otsenka sub''ektivnoi sekundy pri pomoshchi testa "individual'naia minuta".

Correlation of the two characteristics of the "individual minute" test with age and sex of the subjects was examined in 151 persons. Close correlation was observed between the first (counting in the course of 60 s) and the second (counting time up to 60 s) modes of testing, but not between the two modes of testing and age and sex. Results are discussed from the viewpoint of the existence of the common system of time interval estimation the method of their quantum organization being used in different investigation modes.

Dynamics of the temporal parameters of sensorimotor reactions as a function of movement type in man.

An investigation consisting of two series was carried out on nine healthy male subjects, age 20-24 years. In the first series, a warning signal and then four symbols which required a simple or a complex reaction were presented sequentially on a display screen. In the second series, asterisks were presented instead of the symbols. The sequence of reactions was performed from memory. The results of the investigations made possible the identification of two specific features: a significant decrease in RT in the series of reaction from memory, and a successive decrease in RT with a decrease in the number of the remaining signals in the block of signals. In the first series, the RT decreased successively by 35-40 msec, and in the second, by 16-20 msec. It is hypothesized that the difference in RT between the series characterizes the time of analysis of one signal, and the difference, on the other hand, in the RT within the limits of a single block in the second series characterizes the time for the retrieval from memory of the motor program.

[Dynamics of temporal parameters of sensorimotor reactions in relation to the type of human movement]. / Dinamika vremennýkh parametrov parametrov sensomotornykh reaktsii v zavisimosti ot tipa dvizheniia u cheloveka.

The study was conducted on nine right-handed male subjects 20-24 year old and consisted of two series. In the first series one warning signal in the form of one of the digits (from 1 to 8) was successively presented to the subjects on the display and then four trigger signals which required either simple pressing of the push button (an arrow with a dot) or its holding during 0.5 s (two arrows) by the right or left hand depending on the arrow direction. The digit corresponded to one variant of signals succession. Each variant was repeated randomly among other variants 15 times. In the second series instead of arrows asterisks were presented. Reaction time and duration of push button holding were recorded. Two regularities were observed: significant decrease of RT in the series of reacting by memory and successive decrease of RT in accordance with the decrease of the number of the remaining signals observed in both series. In the first series RT successively decreased by 35-40 ms, in the second one-by 16-20 ms. It is supposed that the difference in RTs between series characterizes the time of signal structure analysis, while the difference in RTs within one block of signals in the second series-the time of extraction of selected motor program from memory.

[Reproduction of time intervals by humans predicting signals]. / Vosproizvedenie intervalov vremeni chelovekom v usloviiakh proizvedeniia signalov.

Three series of experiments were carried out on 21 subjects. In the first series the subjects were presented with two temporal intervals--500 and 800 ms, limited by electrocutaneous stimuli of 1 ms duration. According to the instruction, the subjects reproduced them, pressing the left or right button, correspondingly. In the other two series, the subjects made the prognosis of presentation of the one or the other interval by corresponding reaction, after which they were presented with the real interval (at P = 0.5/05 in the 2nd series and P = 0.2/08 in the 3d series), which also had to be reproduced. In reproduction of temporal intervals without preliminarily prognosis, the number of wrong reactions reached 12%. In conditions of preliminary prognosis at equally probable signals distribution, the number of wrong reactions was equal to the number of correct ones, and at different probabilities, for rather improbable signals it exceeded twice,--and for more probable--it was twice less than the number of correct responses. Besides, the accuracy of interval reproduction depended on the prognosis of signals distribution but it could correspond to the really perceived interval and not to the interval chosen at prognosis. The reaction time, as the experiments showed, at prognosis was significantly greater than the reaction time of interval reproduction.

[Effect of the duration of a reproducible interval on reaction time in man]. / Vliianie dlitel'nosti vosproizvodimogo intervala na vremia reaktsii u cheloveka.

The dependence of reaction time (RT) of reproduction of presented standard intervals on their duration (100-5000 ms) was studied on 30 subjects. The intervals were limited by two electrocutaneous stimuli or two clicks and were presented both at random and at a gradual increase or decrease, with a step of 100 ms. They were reproduced by pressing a button. The RTs duration depended on the presented interval within the range from 100 to 2000 ms. Such scatter of the upper limit is due to differences in the methods of presentation of the material and to individual features of the subjects. A presence of two mechanisms of time intervals reproduction is suggested for such experimental conditions: the image of the standard interval might be created either after its presentation or in the process of its presentation. Correspondingly, the RT dependence on the interval duration is manifest in the first case and is absent in the second.