Motion of grains, droplets, and bubbles in fluid-filled nanopores.

Molecular dynamics studies of nanometer-sized rigid grains, droplets and bubbles in nanometer-sized pores indicate that the drag force may have a hydrodynamic form if the moving object is dense and small compared to the pore diameter. Otherwise, the behavior is nonhydrodynamic. The terminal speed is insensitive to whether the falling droplet is made of liquid or a solid. The velocity profiles within droplets and bubbles that move in the pore are usually nonparabolic and distinct from those corresponding to individual fluids. The density profiles indicate motional shape distortion of the moving objects.

Dynamical chaos and power spectra in toy models of heteropolymers and proteins.

The dynamical chaos in Lennard-Jones toy models of heteropolymers is studied by molecular dynamics simulations. It is shown that two nearby trajectories quickly diverge from each other if the heteropolymer corresponds to a random sequence. For good folders, on the other hand, two nearby trajectories may initially move apart but eventually they come together. Thus good folders are intrinsically nonchaotic. A choice of a distance of the initial conformation from the native state affects the way in which a separation between the twin trajectories behaves in time. This observation allows one to determine the size of a folding funnel in good folders. We study the energy landscapes of the toy models by determining the power spectra and fractal characteristics of the dependence of the potential energy on time. For good folders, folding and unfolding trajectories have distinctly different correlated behaviors at low frequencies.

Investigation of stretching vibrations of glycosidic linkages in disaccharides and polysaccharides with use of IR spectra deconvolution.

The results are presented for the deconvolution of IR spectra of disaccharides and polysaccharides with alpha and beta configurations of the 1 --> 4 glycosidic linkage (maltose, cellobiose, amylose, and cellulose), as well as of their corresponding monosaccharides (alpha- and beta-D-glucose) in the 1200-920 cm(-1) frequency range. It is established that a characteristic of di- and polysaccharides with 1 --> 4 glycosidic linkage is the appearance of new absorption bands in the 1175-1140 cm(-1) spectral range, as opposed to the IR spectra of monosaccharides. This can be a spectroscopic manifestation of the glycosidic linkage formation. In the 1000-970 cm(-1) frequency range, absorption bands, which are not observed in the monomer spectrum, are separated as a result of the deconvolution of the IR spectra of cellobiose and cellulose. The number of bands in this range remains unchanged for maltose and amylose, as compared to the monomer spectra. It is shown that the application of the method of deconvolution leads to a considerable enhancement in the resolution of the absorption bands in the IR spectra of mono-, di-, and polysaccharides.

Abnormal recognition of facial expression of emotions in depressed patients with major depression disorder and schizotypal personality disorder.

The aim of this paper is to study the recognition of facial expression of emotions in depressed patients with major depressive disorder (MD) and schizotypal personality disorder (STP). The pictures of sad, emotionally neutral, and happy faces followed by a masking stimulus were displayed for 80 msec on a computer screen randomly in the left or right hemifield of vision (LHF and RHF). The subjects had to respond by pressing a three position key. Multiple analysis of variance revealed that all depressed patients, relative to control subjects, made more errors in a task of recognition of facial affect. The characteristics of impairment of performance were found to be related to the nosology of depression. MD patients revealed significantly impaired recognition of negative (in LHF and in RHF) and positive (in LHF) facial emotions, as well as poorer recognition in the right hemisphere, and reduced hemispheric asymmetry. In remission, they showed statistically significant recovery of recognition function. STP patients were less impaired and showed slightly poorer recognition of sad (in RHF) and happy (in LHF) expressions. This group demonstrated significantly poor recognition of happy expressions, and more marked dysfunction of the left hemisphere. In remission, STP patients failed to improve in recognition of emotion. This suggests, that the features of emotion recognition in MD and STP groups reflect some differences in the neurophysiological mechanisms underlying the affect-related dysfunction in these groups of depressed patients.

[The recognition of normal emotions and emotions in affective disorders]. / Opoznanie émotsii v norme i pri affektivnykh rasstroistvakh.

Recognition of emotions by face expression was studied in 20 healthy subjects and 20 patients with endogenous depression. Pictures of sad, laughing and neural faces were displayed on computer screen and administered to the center of the visual field and to the right or left visual hemifields during 40-160 ms. Healthy subjects demonstrated more accurate recognition of emotional expression than the neutral expression; the right hemisphere dominated in discrimination of laughing faces. Depressed patients showed the overall impairment of facial expression recognition, which was the most significant for discrimination of sad faces; there were no interhemispheric difference. Discriminant analysis showed that activity of the right hemisphere is crucial for discrimination of healthy subjects and patients with endogenous depression. Possible mechanisms of impairment in recognition of emotional facial expressions in depressed patients are discussed.

[Reproduction of leukovirus RD-114 in diploid and heteroploid human cells]. / Reproduktsiia leikovirusa RD-114 v diploidnykh i geteroploidnykh kletkakh cheloveka

The capacity of leukovirus RD-114 to replicate in human embryo lung diploid cell cultures and continuous human angiosarcoma cell cultures (AS and 709 lines). Differences in the capacity to support the virus reproduction were observed in the two strains of human embryo lung cells (HEL-1 and HEL-3) and the two continuous angiosarcoma cell lines. No virus reporduction was observed in mouse and rat cell cultures. No cytopathic or transformation changes were caused by the virus in any of the systems examined.