The paper continues the cycle of studies on the evolutionary link between the mechanisms of stress response formation and cognitive functions started in 1959 by M.E. Lobashev and V.B. Savvateev. We ...explore the role of a key neuroplasticity factor LIM kinase 1 (LIMK1) expressed in dopaminergic and serotonergic neurons in Drosophila genome stability, as well as learning and memory, both in standard conditions and when an organism exhibits a stress response to Earth’s weakened static magnetic field (WSMF). We demonstrate that a low LIMK1 level promotes learning acquisition, but not the formation of intermediate-term memory; at the same time, stress exposure restores the learning ability and memory formation in the Drosophila strain with an increased LIMK1 content. We identify inter-strain differences in the frequency of DNA double-strand breaks (DSBs) and show an increase in DSBs after the exposure to WSMF. The data obtained reveal the role of dopaminergic and serotonergic neurons not only in cognitive functions, but also as WSMF targets in the development of a stress response.
Cell suspension of a medicinal plant
Polyscias filicifolia
recovered after 5 years of cryopreservation in liquid nitrogen (− 196 °C) was cultured in 250 ml flasks and laboratory (20-l), pilot (75-l) ...and industrial (630-l) bioreactors operated under batch and semi-continuous regimes. Growth parameters of the recovered cell culture were compared to those recorded before cryopreservation and after 5 years of culture maintenance in the active collection with 2 weeks subculture intervals. The results revealed that cell viability, maximum accumulation of fresh and dry weights, specific growth rate and productivity on dry biomass in flasks and bioreactors of different types and volumes were not affected by cryopreservation. In 20-l bioreactors, longer lag phase was observed for cell culture maintained for 5 years by periodic subcultures compared to the initial and cryopreserved cell cultures, however, all differences in growth dynamics were mitigated during cultivation in 630-l bioreactors. This study demonstrates that cryopreservation is a reliable and effective method for conservation of
P. filicifolia
cell culture for biotechnological applications.
Key message
Cell suspension of a medicinal plant
Polyscias filicifolia
recovered after 5 years of cryopreservation fully retained its original growth and productivity when cultured in bioreactors from 20 to 630 l.
The effect of carbon nanofibers introduced into the polyimide matrix on the mechanical properties of initial nanocomposite films and nanocomposite films oriented by uniaxial drawing at various stages ...of polyimide synthesis is studied. It is demonstrated that the storage moduli of nanocomposite films are higher compared to initial polyimide films at equal draw ratios. The self-orientation ability of the studied samples drawn at the stage of a prepolymer (poly(amic acid)) during thermal imidization is revealed, and it is shown that this ability increases upon the introduction of carbon nanofibers into the polyimide matrix. It is found that the polyimide films with the highest rigidity of macromolecules among the studied structures exhibit the highest storage moduli owing to their high self-orientation ability. Using X-ray diffraction and electron microscopy, a change in the supramolecular structure of rigid-chain polyimide films upon their orientational drawing at various stages of synthesis is investigated.
The activity of a 5
wt% Cu/CeO
2−
x
catalyst during preferential CO oxidation in hydrogen-rich gas mixtures was studied in a microchannel reactor. An increase of the O
2 concentration from a 1.2 to 3 ...fold excess reduced the CO concentration to 10
ppm in a broad temperature interval of 50
°C at weight hour space velocity (WHSV) up to 275,000
cm
3
g
−1
h
−1. The preferential CO oxidation could be carried out at higher flow rates and at higher selectivities in the microchannel reactor compared to a fixed-bed flow reactor.
▪
The activity of a 5-wt% Cu/CeO
2−
x
catalyst during preferential CO oxidation in hydrogen-rich gas mixtures was studied in a microchannel reactor. The CO concentration dropped from 1
vol.% to 10
ppm at a selectivity of 60%, at a temperature of 190
°C, and a weight hour space velocity (WHSV) of 55,000
cm
3
g
−1
h
−1. Both the CO concentration and the temperature increased when the WHSV was increased from 50,000 to 500,000
cm
3
g
−1
h
−1. An increase of the O
2 concentration from a 1.2 to 3 fold excess reduced the CO concentration to 10
ppm in a broad temperature interval of 50
°C at WHSVs up to 275,000
cm
3
g
−1
h
−1. The preferential CO oxidation could be carried out at higher flow rates and at higher selectivities in the microchannel reactor compared to a fixed-bed flow reactor.
The review examines the principles in formation of cell culture and tissue collections of higher plants in vitro as a variant of genetic collections, the modern state and perspective of using ...collections in studies of the peculiarities and patterns of synthesis of biologically active substances of higher plants, the important role of collections in biotechnological production of substances for medicinal preparations, and methods for maintaining the stability of cell cultures during long-term cultivation. Particular attention is paid to the retrospective and current state of the All-Russia Collection of Cell Cultures of Higher Plants, the founder of which was Russian Academy of Sciences Corresponding Member R.G. Butenko.
The Stratigraphic Drilling Project of the Russian Arctic Shelf, conducted by the Rosneft Oil Company, focuses their attention on the stratigraphic age and composition of rock complexes of the ...sedimentary basins. In 2021, six shallow boreholes for the first time were drilled with core sampling in the eastern part of the Laptev Sea. Drilling recovered sedimentary rocks of the folded basement that have been dated to the Late Barremian–Early Aptian. The synrift complex lying with angular unconformity has been dated to the Paleocene. The section of the overlying Eocene–Pleistocene sediments contains significant hiatuses. The data obtained by drilling together with the results of seismic interpretation allowed us to clarify the regional geological model and to date the stages of its tectonic evolution.
Justification of impregnation modes for wood Gazizov, A M; Samosenko, E G; Popova, E V
Journal of physics. Conference series,
07/2021, Letnik:
1967, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Abstract
One of the most significant disadvantages of wood materials is increased combustibility. Therefore, the problem of reducing the combustibility of wood materials is relevant. The article ...describes an experimental study of impregnation of wood using biopiren MIG-09, which is a hybrid composition on a salt basis with the addition of functional substances of non-salt nature, at different temperature regimes. Two stages of the study were chosen for the experiment. The optimum temperature regimes for different methods of applying the composition to increase the fire resistance of wood were established experimentally. Also fire tests were carried out to analyze the degree of penetration of the solution.
The effectiveness of drug penetration into the inner tissues of the eye under local application is significantly limited by the barrier effect of the cornea and by the washout of the drug with the ...lacrimal fluid. To increase the bioavailability of a drug, it is proposed to include the drug in the chitosan particles formed by two types of chitosan: 5 kDa chitosan and 72 kDa glycol-chitosan. Chitosan particles with the loaded angiotensin-converting enzyme inhibitor enalaprilat, capable to reduce intraocular pressure, are characterized by dynamic light scattering and scanning electron microscopy. Particles formed by 5 kDa chitosan have an average hydrodynamic diameter from 85 to 125 nm and a positive ζ potential of +21 ± 3 mV, while particles formed by 72 kDa glycol-chitosan have a size from 440 to 480 nm and are characterized by a ζ potential of +10 ± 2 mV. The percentage of enalaprilat inclusion in the chitosan particles is 25% and 40%, respectively. In vivo experiments showed that the inclusion of the drug int the chitosan particles can increase the retention time of enalaprilat in the lacrimal film of rabbits.
Organic-inorganic composites filled with nanoscale graphene and tungsten disulfide particles using thermoelastoplastic multiblock co-poly(urethane-imide)s as polymer matrices were obtained. The ...matrix polymers were the products of the polycondensation of 1,3-bis-(3′,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(aminophenoxy)diphenyl sulfone, and two aliphatic polyesters terminated by 2,4-toluene diisocyanate, namely, polypropylene glycol (M
n
= 2300) and poly(ethylene adipate) (M
n
= 2700). The weight fraction of aromatic segments in samples of co-poly(urethane-imide)s differed by a factor of two. Obtained composites were investigated by TGA, DSC, and DMA methods.
Nanomodified polyetherimide samples obtained by fused deposition modeling using an experimental setup for three-dimensional printing of highly heat-resistant plastics are studied. Their structure and ...thermal properties are investigated by pycnometry, scanning electron microscopy, differential scanning calorimetry, thermogravimetry, and dilatometry. It is found that the modification of polyetherimide with carbon nanofibers considerably reduces the porosity of printed samples. An analysis of cytotoxicity shows that the tested materials are bioinert.
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