Abstract
Modeling helps to investigate and analyze the interrelationships of grinding parameters as a single system. The article describes a computer model of the surface layer of a grinding wheel, ...taking into account the cutting modes and characteristics of the circle. The subsystem of the surface layer of the grinding wheel is the most important subsystem of grinding, since it connects the main characteristics of the circle with the cutting modes and with the parameters of the workpiece. The output characteristics of the model are the parameters of the working layer with a height of several micrometers, in which micro-cutting occurs. It is impossible (or very difficult) to obtain them by conducting full-scale experiments, since the processes are instantaneous, and the cutting elements have micro-dimensions. This problem was solved by creating a simulation stochastic model based on the geometric representation of the surface layer, which clearly displays the result. The analysis of the image of this model allowed us to numerically describe the output parameters of cutting.
The article offers a faster algorithm for analyzing the image of the simulation model of the surface layer. It is carried out over a matrix containing numerical information about the projection of the surface layer, the main parameters of each single slice are calculated, and only after that the result is displayed on the graphic screen. To simulate a single grinding mode, it is necessary to repeat the process of "image creation - image analysis– output of results" hundreds of times until a stable state is reached.
The use of the algorithm in an automated system will allow you to create a system for automatically searching for optimal grinding modes, as well as to derive analytical dependencies of cutting modes on input parameters, for example, on the parameters of the circle and the workpiece.
Calcium aluminosilicates synthesized by chemical modification of nanostructured synthetic Na zeolites were characterized. The sorption properties were studied for calcium aluminosilicates with SiO
2
...: Al
2
O
3
ratios of 2 : 1, 4 : 1, 6 : 1, 8 : 1, and 10 : 1. The maximum capacity of these compounds to sorb Cs
+
ions under static conditions from solutions without salt background was shown to reach 1.45 mmol/g (192.7 mg/g). The results of this work allow one to consider these compounds as promising materials for the sorption and immobilization of long-lived radionuclides.
The sources of supply and transformation of organic matter (OM) as it transitions from dissolved form to particulate matter, fluffy layer, and bottom sediments were investigated along a meridional ...transect from the Lena River delta to the continental slope (in the depth range of 10 to 2390 meters, cruise 63 of the R/V
Akademik Mstislav Keldysh
, September 2015). The study of OM molecular markers showed that dissolved and particulate organic matter of marine and terrigenous origin biodegrades in the water column and accumulates insignificantly in bottom sediments. Thus, OM from Lena River runoff does not contribute to the formation of OM in bottom sediments in summer. An area of influence of under-ice blooms on the sedimentation process was identified on the outer shelf.
A refined mathematical model is proposed that describes the process of nonlinear deformation of semi-infinite plates made of fiber reinforced plastics. It belongs to Reddy–Nemirovsky class of models ...and uses a linear approximation for deflection and a cubic approximation for tangential displacements over the plate thickness. The constructed approximations satisfy the boundary conditions for tangential forces at the points of the boundary (facing) planes. Kinematic relations for determining the components of deformations are constructed on the basis of consistent geometrically nonlinear relations of the theory of elasticity, taking into account the terms that allow to identify classical and non-classical (in particular, transverse shear under transverse bending conditions) buckling modes of the plate. The physically nonlinear material behavior is accounted in the relations for transverse shear stresses. The issues of the correctness of the constructed equations for different conditions of fixing and loading of end sections of the plate are considered. It is obtained that in solutions determined on the basis of the constructed equations and satisfying the boundary conditions of the clamped cross section, the transition to the solution according to the classical Kirchhoff–Love model in the clamped area is carried out.
Previous studies have shown that in the blood of healthy donors (1) there are no natural antibodies against sialylated glycoproteins, which contain Neu5Ac (N-acetylneuraminic acid) as the most ...widespread form of human sialic acid, and (2) there is a moderate level of antibodies capable of binding unnatural oligosaccharides, where Neu5Ac is beta-linked to a typical mammalian glycan core. In the present study, we investigated antibodies against Neu5Ac in more detail and verified the presence of Kdn (2-keto-3-deoxy-D-glycero-D-galacto-nonulosonic acid) as a possible cause behind their appearance in humans, taking into account the expected cross-reactivity to Kdn glycans, which are found in bacterial glycoconjugates in both the - and -forms. We observed the binding of peripheral blood immunoglobulins to sialyllactosamines (where sialyl is Kdn or neuraminic acid) in only a very limited number of donors, while the binding to monosaccharide Kdn occurred in all samples, regardless of the configuration of the glycosidic bond of the Kdn moiety. In some individuals, the binding level of some of the immunoglobulins was high. This means that bacterial Kdn glycoconjugates are very unlikely to induce antibodies to Neu5Ac glycans in humans. To determine the reason for the presence of these antibodies, we focused on noninfectious pathologies, as well as on a normal state in which a significant change in the immune system occurs: namely, pregnancy. As a result, we found that 2/3 of pregnant women have IgM in the blood against Neu5Ac2-3Gal1-4GlcNAc. Moreover, IgG class antibodies against Neu5Ac2-3Gal1-4GlcNAc and Neu5Ac2-6Gal1-4GlcNAc were also detected in eluates from the placenta. Presumably, these antibodies block fetal antigens.
Hypothesis: Marine threespine stickleback manifest homing ability and site fidelity during their spawning period. Organism: The threespine stickleback, Gasterosteus aculeatus. Time and places: June ...2015 and June 2016 (during the stickleback spawning period), Koliushkovaya Lagoon, Kandalaksha Bay, the White Sea. Methods: Stickleback were tagged on their inshore spawning grounds about 2 weeks after their inshore migration. We attached plastic tags to their dorsal spines, displaced them 100–300 m away from shore, and recaptured them inshore after periods of one hour to four days. Results: Stickleback caught on their spawning grounds in the lagoon, tagged and displaced a few hundred metres, were able to return to their home site within a day. Males and females exhibited no differences in homing ability. Most fish left their home site within four days of returning, however, indicating that site fidelity is weak. Stickleback caught outside the lagoon in the sea, and tagged and released in the lagoon, spread along the shore in accordance with the density of local fish.
The phenological development of 13 taxa of North American maples for 2013–2020 has been analyzed on the basis of the collection of the South Ural Botanical Garden-Institute, Ufa Federal Research ...Center, Russian Academy of Sciences. The sum of positive, effective, and active temperatures and the sum of precipitation required for the onset of the main phenophases have been calculated. Most phenophases depend on weather conditions, except for the phases of the beginning and end of flowering and fruit ripening: they are genetically determined. This fact explains the large difference in the sum of temperatures and precipitation at the beginning of these phases in different species. The sum of positive temperatures at the beginning of flowering is 11–497°C; the amount of precipitation is 33–80 mm. At the end of flowering, the sum of positive temperatures at the beginning of flowering is 149–722°C; the amount of precipitation is 43–112 mm. The number of positive temperatures attributable to the phenophase of fruit ripening varies from 693 to 2662°C, and the amount of precipitation by this time varies from 47.5 to 315 mm. The duration of vegetation of North American maples in Ufa, depending on the species, ranges from 140 (
A. tschonoskii
) to 172 days (
A. rubrum
Summer Red).
The article describes the relevance of the study of public spaces as an important element of the quality of the urban environment. Successfully functioning public spaces are called upon to solve a ...number of urban problems, including the social isolation of citizens caused by urbanization processes. The characteristic of public spaces of a particular city is based on an assessment of a set of attributes and related criteria developed by placemaking specialists. It is proved that this complex should reflect not only the general requirements for public spaces, but also the features of the city: the diversity of the socio-ethnic structure of the population, cultural and historical heritage, and the specificity of the existing urban environment. The characteristics of the four most visited public spaces of the provincial Siberian city of Irkutsk are fulfilled: the Kirov square; historical and memorial complex "Jerusalem Mountain "; Municipal Park "Yunost Island"; shopping and entertainment complex "130th quarter". The results showed that the public spaces of the city perform a number of functions with varying degrees of success: best recreational and entertaining, partially creative and the function of storing the "collective memory" of the city. At the same time, the city does not have public spaces that fully meet the objectives of the development of urban society; this applies to both historical and newly created. Their main drawback is the inconsistency with the modern challenge for Irkutsk, namely, the solution to the problem of social inclusion of new citizens. Some measures have been proposed for City management to purposefully strengthen the elements of public spaces that implement the function of involving residents, especially migrants, in the public life of the city.
For the first time data on parasite diversity of Syngnathidae fishes inhabiting the Black and the Sea of Azov, the rivers flowing into these seas and their estuaries accumulated in more than 30 ...articles and books during almost one century of investigations were summarized. A high level of parasitic organisms’ richness is registered to date: 64 species from 45 genera, 35 families, 14 classes, 10 phyla have been recorded here from eighth species of Syngnathidae fish hosts:
Syngnathus abaster
Risso, 1827;
S. acus
L., 1758;
S. schmidti
Popov, 1927;
S. tenuirostis
Rathke, 1837;
S. typhle
L., 1758;
S. variegatus
Pallas, 1814;
Nerophis ophidion
(L., 1758);
Hippocampus hippocampus
(L., 1758). Host-parasite and parasite-host lists are provided, the results for Kinetoplastida, Sporozoa, Microsporidia, Myxozoa, Ciliophora, Platyhelminthes (Monogenea, Trematoda, Cestoda), Nematoda, Acanthocephala, Annelida, and parasitic Arthropoda are presented. Platyhelminthes and Ciliophora (19 and 18 species, respectively) turned out to be the most species-rich taxa of Syngnathidae parasites, while Trematoda was the richest (15 species) class among flatworms. The largest number of parasite species is known from three fish hosts:
S. abaster
parasite fauna comprises 54 species of 10 phyla (84% of total parasite fauna of this fish family in the region),
S. typhle
—27 parasite species belonging to six phyla (38%, respectively) and relatively pure parasites fauna in
H. guttulatus,
14 species of six phyla (22%).
Sensory Gating in TAAR1 Knockout Mice Aleksandrov, A. A.; Dmitrieva, E. S.; Knyazeva, V. M. ...
Journal of evolutionary biochemistry and physiology,
07/2022, Letnik:
58, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Trace amines (TA) are a family of endogenous compounds structurally similar to classical biogenic amines that may be involved in the pathogenesis of a number of neuropsychiatric disorders. One of the ...most studied and perspective member of the TA associated receptors (TAARs) family is the TAAR1. The aim of the present study was to investigate the sensory gating (SG) in freely moving TAAR1 knockout mice in a chronic experiment. The study of SG was conducted in the paired-click paradigm. The SG indices were calculated as an absolute value by subtracting the second stimulus response amplitude from the first stimulus response amplitude (S1–S2) and as a relative value calculated by dividing the S2 amplitude by the response amplitude on S1 (S2/S1). As a result, a significant decrease in the amplitude of the N40 component was found in TAAR1 knockout mice compared to wild-type mice. In addition, the absolute value of sensory gating calculated by the S1–S2 method was also reduced, but the relative value of sensory gating denoted as S1/S2 ratio remained unchanged. Thus, the data obtained indicate the involvement of TAAR1 in the generation of auditory evoked potentials and the potential involvement of the trace amine system in the dosing and filtering of sensory information.
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