122 research outputs found
Development of practice oriented education structures improving professional education
This paper is about the modern aspects of the development of professional education taking into account the implementation of the Universities of applied programs of a bachelor degree. Main directions of improving the professional training, retraining and raising qualification of specialists in the framework of practice oriented education structures.В статье рассматриваются современные аспекты развития профессионального образования с учетом реализации вузами программ прикладного бакалавриата. Предложены направления совершенствования профессиональной подготовки, переподготовки и повышения квалификации специалистов в рамках практико-ориентированных образовательных структур
Asymmetric Electrostatic Dodecapole: Compact Bandpass Filter with Low Aberrations for Momentum Microscopy
Imaging energy filters in photoelectron microscopes and momentum microscopes
employ spherical fields with deflection angles of 90{\deg}, 180{\deg} and even
2 x 180{\deg}. These instruments are optimized for high energy resolution, yet
they come along with image aberrations when they are operated in high
transmission mode with medium energy resolution. Here we present a new approach
for bandpass-filtered imaging in real or reciprocal space, using an asymmetric
electrostatic dodecapole. This multipole enables energy-dispersive beam
deflection and correction of image aberrations up to the 3rd order. Owing to a
deflection angle of only 4{\deg}, the total beam displacement in the filter is
just ~10 mm. Hence, the entire instrument is compact and just requires a
straight vacuum tube. The multipole is framed by transfer lenses in the
entrance and exit branch. Two sets of 16 entrance and exit apertures with
different sizes on piezomotor-driven holders allow selecting the desired
resolution. The combination of apertures and dodecapole acts as a bandpass
pre-selector in a high-energy time-of-flight momentum microscope at the hard
X-ray beamline P22 at PETRA-III (DESY, Hamburg). At pass energies between 400
and 600 eV it transmits electrons with kinetic energies in the range of 20-40
eV and thus effectively eliminates unwanted intensity from higher-energy
electrons in the ToF analyzer. At low pass energies, the instrument allows
energy-filtered imaging without subsequent ToF analysis. In a laboratory
experiment the 4{\deg} prototype reached < 500 meV resolution, which is
sufficient for fast survey studies in the X-ray range.Comment: 16 pages, 6 figures, 26 reference
Microsurgical dissection methods for embryonic cloning of monozygotic twins
To date, biotechnological methods for producing double grains play an important role in increasing the production of milk and meat. At the same time, monozygotic twins are of particular interest for assessing the heritability of quantitative traits, breeding value when studying the influence of the maternal effect on offspring and creating reserve genes with known properties. However, in cattle, the frequency of birth of twins is only 0.025%, and the appearance of identical twins is only 0.01%. The reasons for the separation of embryos in the process of ontogenesis are unknown, but their production became possible with the development of genetic engineering methods, which include embryonic cloning by microsurgery of early embryos (dissection). The results of research in this area are mostly not applied, which is due to the high cost of micromanipulation equipment and the complexity of the procedure due to the large number of micro-tools. Today, the development of simplified methods of microsurgical manipulations on embryos remains an urgent task. In this regard, the aim of the research was to study the possibility of simplifying the existing technology of microsurgical dissection of preimplantation embryos by developing appropriate tools. In connection with this goal, the tasks of developing a device for simplifying the dissection procedure and determining its effectiveness in comparison with the use of a micromanipulator with one tool were determined. The development of the device and its practical application were carried out in 2021-2023 at the Regional Research and Production Center for the Reproduction of Farm Animals of the Kalmyk State University named after B.B. Gorodovikov. The conducted studies showed the following results: the efficiency of using a micromanipulator with one microscalpel was 86.1%: as a result of dissection of 61 embryos, 105 full-fledged demiembryons out of 122 possible ones were obtained. The efficiency of the developed device was 10.2% higher – after separation, 27 embryos received 52 compacted demiembryons out of 54 possible (96.3%)
Случай оперативного лечения язвенной болезни двенадцатипёрстной кишки с перфорацией в брюшной отдел аорты
Случай оперативного лечения язвенной болезнидвенадцатипёрстной кишки с перфорацией в брюшной отдел аорт
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2D/3D Metallic Nano-objects Self-Organized in an Organic Molecular Thin Film
We present the fabrication and investigation of the properties of nanocomposite structures consisting of two-dimensional (2D) and three-dimensional (3D) metallic nano-objects self-organized on the surface and inside of organic molecular thin-film copper tetrafluorophthalocyanine (CuPcF4). Metallic atoms, deposited under ultrahigh vacuum (UHV) conditions onto the organic ultrathin film, diffuse along the surface and self-assemble into a system of 2D metallic overlayers. At the same time, the majority of the metal atoms diffuse into the organic matrix and self-organize into 3D nanoparticles (NPs) in a well-defined manner. The evolution of the morphology and electronic properties of such structures as a function of nominal metal content is studied under UHV conditions using transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), and photoelectron spectroscopy (PES) techniques. Using HR-TEM, we have observed the periodicity of atomic planes of individual silver NPs. The steady formation of agglomerates from individual single nanocrystallites with intercrystallite boundaries is observed as well. PES reveals generally weak chemical interactions between silver and the organic matrix and n-doping of CuPcF4 at the initial stages of silver deposition, which is associated with charge transfer from the 2D wetting layer on the basis of core-level spectra shift analysis. Copyright © 2020 American Chemical Society
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