Automatic checkout systems to monitor driver's vigilance.

A concept for designing automatic checkout systems to prevent drivers from falling asleep is presented. It is shown that such systems should use the frequency of electrodermal reactions (EDR), which is governed by changes in skin resistance. Such changes have a time constant of several seconds. To detect these reactions, a special technique was developed. Experimental investigations yielded the quantitative characteristics of EDR changes associated with decreased vigilance. It was found that, when a person started to fall asleep, the EDR frequency diminished. An EDR-based system was developed to assess the alertness level. Such a system may be employed to prevent drivers from falling asleep.

[Use of rare earth elements as markers for the study of biologically active compounds. V. Luminescence spectra and binding centers of europium in proteins]. / Primenenie redkozemel'nykh élementov v kachestve metki dlia issledovaniia biologicheskie aktivnykh soedinenii. V. Spektry liuminestsentsii i tsentry sviazyvaniia evropiia v nekotorhykh belkakh

Luminescence spectra of europium ions bound to some proteins are investigated. Europium is shown to coordinate no more than two charged groups, first of all carboxyles. The possibility of more specific coordination of rare earths in proteins is discussed.

[Application of rare-earth elements as labels in studying bilogically active compounds. II. Luminescence spectra and structure of europium complexes for use as shift reagents in NMR studies]. / Primenenie redkozemel'nykh élementov v kachestve metki dlia issledovaniia biologich'ski aktivnykh soedinenií. II. Spektry liuminestsentsii i stroenie kompleksov evropiia primenimykh v kachestve shift-reagentov pri issledovaniiakh metodom IaMR

The luminescence spectra and solubility of several europium complexes are investigated. The conditions put upon the complex structure for its successful use as a shift reagent are discussed. Some water-soluble europium complexes with pyridoxaliden amino acids are shown to be fit as possible shift reagents.

[Use of rare-earth elements as labels for studying biologically active compounds. IV. Luminescence spectra and structure of compounds of europium with nucleotides]. / Primenenie redkozemel'nykh élementov kak metki dlia issledovaniia biologicheski aktivnykh soedinenii. IV. Spektry liuminestsentsii i stroenie soedinenii evropiia s nukleotidami

Spectra of europium coordinating nucleotides are investigated. Europium is shown to coordinate phosphate, but the way of coordination may change. Conditions of nitrogen bases coordination are determined. The evidence or the existence of coordinated immobilized water is found.

[Conformation of lanthanide complexes with Schiff bases of pyridoxal and dipeptides]. / Konformatsiia kompleksov lantanidov s shiffovymi osnovaniiami piridoksalia i dipeptidov.

In order to simulate the active centres of pyridoxal enzymes, lanthanide complexes of pyridoxal-dipeptide (gly-asn) azomethines were investigated by means of NMR 1H and optical spectroscopy. NMR spectra were shown to correspond to conformation averaged over two positions of the ion. The ion was bound to the oxygen atom of PL and nitrogen atom of azomethine. In addition, it coordinates the oxygen atom of the peptide bond or the asparagine carboxyl.

[Application of rare-earth elements as labels in studying biologically active compounds. I. Luminescence spectra of solutions of complexes of pyridoxaldiene amino acids with europium]. / Primenenie redkozemel'nykh elementov v kachestve metki dlia issledovaniia biologicheski aktivnykh soedinenii. I. Spektry liuminestsentsii rastvorov kompleskov piridoksalidenaminokislot s evropiem

The luminescence spectra of qater solutions of europium complexes with azometines formed by condensation of amino acids with pyrydoxal are investigated. The differences in luminescence spectra connected with the variations in the complexes structures are found. The possibilities of application of the europium ions luminescence for biochemical reactions investigation and for structure studies and identification of biologicaly active compounds are discussed.

[Application of rare-earth elements as labels in studying biologically active compounds. III. Natural and magnetic circular dichroism of complexes of rare-earth elements with pyridoxalidene amino acid complexes]. / Primenenie redkozemel'nykh élementov v kachestve metok dlia issledovaniia biologicheski aktivnykh soedinenii. III. Estestvennyi i magnitnyi krugovoi dikhroizm kompleksov RZE s piridoksalidenaminokislotami

Circular dichroism of pyrodoxalidenaminoacid complexes with rare earths and other metals and magnetic circular dichroism of several neodimium complexes are investigated. CD spectra of the complexes of the rare earths with azometines made of different amino acids could be classified into four groups. Some of the CD spectra are shown to be individual. The dependence of the CD spectra on the rare earch ion dimension is considered. Coordination of the rare earth ions is shown to be the same as in the case of zinc, cobalt, iron or copper.

[Nucleotide conformation in aqueous solutions by the NMR spectrum lanthanide shift method]. / Issledovanie konformatsii nukleotidov v vodnykh rastvorakh metodom lantanidnogo smeshcheniia spektrov IaMR.

Nucleoside triphosphates, ATP in particular, are investigated by 1H and 31P NMR with lanthanide perchlorate as LSR. The nucleotide base is shown to be near the phosphate groups. Dinucleotides and nucleoside monophosphates are investigated by means of a new LSR--lanthanide complex of pirydoxalidenaspartic acid. NAD+ and its derivatives are shown to exist in folded conformation at high pH values. AMP is shown to undergo conformational change in the pH range between 7 and 8.5. The structure of adduct of new LSR with amino acid is calculated in assumption of unaxial symmetry of the magnetic dipolar interaction. Parameters of the interaction were determined from optical spectra.

[Luminescence, induced by UV-irradiation, of intact human skin]. / Indutsirovannaia UF-oblucheniem liuminestsentsiia intaktnoi kozhi cheloveka.

UV-C induced chemiluminescence of human skin was investigated in vivo by means of an image-producing system using photon-counting camera and computer PERICOLOR-1000. Luminescence after UV-C application is shown to decline nonexponentially, the parameters of the decline depending on irradiation dose, skin specimen and previous irradiations. If the same skin specimen is irradiated second time 3-36 hours after the first irradiation, the luminescence decline time increases from one-two minutes to more than half an hour. During the time when the decline is slow the images produced by irradiation through the diaphragm do not sustain distinct contours due to the luminescence of nonirradiated skin. The luminescence is shown to be under the organisms' control and to diminish significantly after the application of acetylsalicylic acid.

[The electrodermal indices of the subjective perception of performance errors during drowsy changes in consciousness]. / Elektrodermal'nye pokazateli sub''ektivnogo vospriiatiia oshibok v deiatel'nosti pri dremotnykh izmeneniiakh soznaniia.

The study was aimed at searching for objective criteria of subject's perception of errors in performance due to drowsiness and estimating the time between the onset of errors and the moment of their awareness. Healthy subjects (n = 64) with the pronounced EEG alpha were examined under conditions without sleep deprivation. Experiments (n = 280) lasted for 40 min. During the experiments, the EEG, EOG, EDR, EKG, and button pressings were recorded and subject's reports were registered. The subjects were waken up after the onset of errors or 20 min after the beginning of the performance independently of errors. The error onset was shown to be preceded by the EEG "drowsy pattern" and decrease in the rate of spontaneous EDR. The performance reappearance after the error was accomplished by alpha-rhythm independently from error awareness. The interrogation of subjects after the error and activity revival demonstrated a correlation between the error subjective perception and appearance of the EDR. The interval between the error and the first following EDR (mean 10.1 s) was significantly (p < 0.001, t-test for dependent samples) shorter than the interval between the error and the last preceding EDR (mean 69.8 s). It is suggested that the subjective perception of an error is a significant endogenous stimulus, which evokes the orienting response and accompanying sympathetic activation.

[The characteristics of the electrodermal activity during changes in the level of human wakefulness]. / Osobennosti élektrodermal'noi aktivnosti pri izmeneniiakh urovnia bodrstvovaniia cheloveka.

The wake-drowsiness transition during the performance of a monotonous psychomotor test was studied using polygraphic recording, with particular emphasis on changes in the electrodermal activity (EDA) and occurrence of electrodermal reactions (EDR). It was found that decrease in wakefulness was accompanied by a drop of the EDA. The EDR gradually disappeared for several minutes and did not reappear without activation; their dependence on sex and individual features of a subject significantly increased. It is suggested that discrepancies in the experimental results of psychophysiological studies with EDA may be explained by an insufficient control of the subject's alertness throughout the experiment. Examples of such discrepancies are given: disagreement of sex differences in the EDA, differentiation between EDA-labile and EDA-stable persons, on a possibility of recording the "emotional" EDA from different parts of human body etc. The ways of reproducibility of the results are discussed including the recording of several wake-drowsiness transitions and better recognition of the EDR.