The role of nitric oxide in the regulation of neurotransmitter release and processes of exo- and endocytosis of synaptic vesicles in mouse motor nerve endings

In experiments with mouse diaphragm muscle, the effects of a nitric oxide (NO) donor, S-nitroso- N-acetyl-DL-penicillamine (SNAP), and an NO-synthase blocker, NG-nitro-L-arginine methyl ester (LNAME), on transmitter release and processes of exo- and endocytosis of synaptic vesicles in the motornerve ending were studied using electrophysiological and fluorescence techniques. During single stimulation of the motor nerve, SNAP reduced and LNAME did not change the amplitude of the endplate currents and both of the drugs did not affect spontaneous transmitter release. During high-frequency stimulation (20 Hz, 3 min) SNAP increased and LNAME slowed the depression of the amplitudes of endplate potentials (EPPs) compared to the dynamics of EPPs in the control. In experiments using the fluorescent dye FM 1-43, it was shown that the NO donor induced a decrease and LNAME induced an increase in the fluorescence intensity of motor-nerve endings loaded with dye during stimulation at a frequency of 20 Hz for 30 s compared to the control. At the same time, the rate of dye unloading from the terminals that were preloaded with FM 1-43 was higher after preliminary application of SNAP and lower after preliminary application of LNAME. It was suggested that exogenous and endogenous NO in the mouse neuromuscular synapse caused the depression of neurotransmitter release as a result of the suppression of synaptic-vesicle recycling due to a decrease in endocytosis or/and mobilization of synaptic vesicles from a recycling pool to the exocytosis sites. © 2013 Pleiades Publishing, Ltd

X-ray film chamber with carbon target of Tien-Shan complex array

X-ray films were exposed inside the ionization calorimeter under 74g/sq cm of carbon and 5 cm of lead. The X-ray film chamber area is 35 sq. m. Moving X-ray films were used, 50% of the events, which succeeded to determine incidence time, were identified with corresponding extensive air showers (EAS). For such events the size spectrum of associated EAS was derived. Two methods of energy measurement using X-ray films and ionization calorimeter were compared. The energy transfer from selected hadron to electromagnetic component is illustrated. It is found that in cascades with high energy release into electromagnetic components the hadron component is practically absent

Scanning probe microscopy in the study of morphometric changes and physical parameters of Escherichia coli bacteria under the action of 2,4,6 - Trinitrotoluene

Using scanning probe microscopy (SPM) were registered charcteristic structural changes in Escherichia coli K12 cells under the influence of 2,4,6-trinitrotoluene (200 micrograms / ml). According to SPM data, changes were detected not only in the size of cells, but also in the structure of the cell wall. In the presence of TNT, the cell wall becomes less rough, flagellas and pils tend to be absent. However, the height of bacteria does not change. The data of force spectroscopy also showed differences in adhesion forces between the probe and the surface of the bacterial cell wall. In Escherichia coli K12 incubated with TNT there was a tendency to decrease an adhesive force compared with the control. © IDOSI Publications, 2013

Formation of competence of it specialists in the field of evaluating the effectiveness of it projects with the use of electronic educational resources

This article discusses techniques for monitoring the learning process by using the ESM, questionnaires, interviews with teachers and students, pedagogical experiment. The article states the expert role is a list of characteristics of electronic educational resources, subject evaluation. The paper concludes that using the methods of pedagogical research may determine the effectiveness of the used type of electron educational resourceВ статье рассматриваются методы наблюдения за процессом обучения при использовании ЭОР, анкетирования, собеседования с преподавателями и студентами, педагогический эксперимент. В статье указывается роль экспертов, приведен список характеристик электронного образовательного ресурса, подлежащего оцениванию. В статье делается вывод, что используя методы педагогического исследования возможно определение эффективности использованного вида электронно-образовательного ресурс

The Stellar Content of the Polar Rings in the Galaxies NGC 2685 and NGC 4650A

We present the results of stellar photometry of polar-ring galaxies NGC 2685 and NGC 4650A, using the archival data obtained with the Hubble Space Telescope's Wide Field Planetary Camera 2. Polar rings of these galaxies were resolved into ~800 and ~430 stellar objects in the B, V and Ic bands, considerable part of which are blue supergiants located in the young stellar complexes. The stellar features in the CM-diagrams are best represented by isochrones with metallicity Z = 0.008. The process of star formation in the polar rings of both galaxies was continuous and the age of the youngest detected stars is about 9 Myr for NGC 2685 and 6.5 Myr for NGC 4650A.Comment: 21 pages, 9 figures, AJ 2004 February, accepte

Cryptic Diversity in Paramecium multimicronucleatum Revealed with a Polyphasic Approach

Paramecium (Ciliophora) systematics is well studied, and about twenty morphological species have been described. The morphological species may include several genetic species. How-ever, molecular phylogenetic analyses revealed that the species diversity within Paramecium could be even higher and has raised a problem of cryptic species whose statuses remain uncertain. In the present study, we provide the morphological and molecular characterization of two novel Paramecium species. While Paramecium lynni n. sp., although morphologically similar to P. multimicronucleatum, is phylogenetically well separated from all other Paramecium species, Paramecium fokini n. sp. appears to be a cryptic sister species to P. multimicronucleatum. The latter two species can be distinguished only by molecular methods. The number and structure of micronuclei, traditionally utilized to discriminate species in Paramecium, vary not only between but also within each of the three studied species and, thus, cannot be considered a reliable feature for species identification. The geographic distribution of the P. multimicronucleatum and P. fokini n. sp. strains do not show defined patterns, still leaving space for a role of the geographic factor in initial speciation in Paramecium. Future findings of new Paramecium species can be predicted from the molecular data, while morphological characteristics appear to be unstable and overlapping at least in some species