288 research outputs found
On the Influence of Corpuscular Fluxes and of Electron Photoloosening Reaction on the Formation of the D-Layer of the Ionosphere
Effect of corpuscular fluxes and electron photoloosening reaction on formation of ionospheric D laye
Quantitative Estimation of the Ratio of GABA-Immunoreactive Cells in Neocortical Grafts
Somatosensory anlage from 17-18 day old rat
embryos were transplanted in place of the
removed barrel cortex in adult rats. Six to eight
months after transplantation, the grafts were
either completely separated by glial scar or
partly separated and partly confluent with the
host neocortex. Each was studied histologically
and immunostained for GABA. It was found that
in partly confluent grafts the neuronal density
was similar or even higher than in the host
cortex, while the cell number in the separate
grafts was much lower than in the nearby host
cortex. The number of GABA-positive cells,
however, was in all grafts significantly lower
(2.9% on average) than in the normal cortex
(11.8% on average).The decline in GABA-stained
nerve cells was highest in separated
grafts, but was somewhat less marked in
transplants partly confluent with the host tissue.
The possible role of partial or total
deafferentation as well as the relative
vulnerability of the transplanted tissue by
temporary hypoxia and other metabolic
disturbances are discussed as the probable
factors in selective decline of GABA-ergic cells in
the transplanted somatosensory cortex
Age-Related Loss of GABA-Positive and GABA-Negative Neurons in Neocortical Transplants
The numerical density of GABA
immunopositive and GABA immunonegative
neurons was quantitatively determined in 0, 12,
30 and 90 day-old neocortical transplants,
derived from E17 rat embryos and transplanted
into adult hosts. It was found that the original,
very high neuronal density in the fetal
transplant declined steadily after
transplantation to the somatosensory cortex of
adult rat. The decline in numerical density of
GABA-positive neurons, however, was
disproportionately larger than that of GABA-negative
nerve cells: At 90 days the proportion
of GABA-positive cells was 2.3% (in contrast to
the 11.8% in the adult host cortex). The density
of GABA-negative neurons, on the other hand,
remained slightly higher than comparable
values in the control cortex. The decline in
density Of GABA-positive neurons was
continuous until the 90th post-transplantation
day, while final, close to normal density values
of GABA-negative nerve cells were already
reached in 30 day-old grafts, with no significant
change afterwards
Collective Modes of Tri-Nuclear Molecules
A geometrical model for tri-nuclear molecules is presented. An analytical
solution is obtained provided the nuclei, which are taken to be prolately
deformed, are connected in line to each other. Furthermore, the tri-nuclear
molecule is composed of two heavy and one light cluster, the later sandwiched
between the two heavy clusters. A basis is constructed in which Hamiltonians of
more general configurations can be diagonalized. In the calculation of the
interaction between the clusters higher multipole deformations are taken into
account, including the hexadecupole one. A repulsive nuclear core is introduced
in the potential in order to insure a quasi-stable configuration of the system.
The model is applied to three nuclear molecules, namely Sr + Be +
Ba, Mo + Be + Te and Ru + Be +
Sn.Comment: 24 pages, 9 figure
‘Tobolyak’: an oat cultivar for universal use
Background. An urgent problem is the development and introduction of cultivars for universal use that can meet the demand of animal husbandry for various types of feed and that of food industry for raw materials. Of great interest in this regard is ‘Tobolyak’, a new spring oat cultivar characterized by a high yield of grain and green biomass.Materials and methods. The cultivar was developed at the Research Institute of Agriculture for the Northern TransUrals, a branch of the Tyumen Scientific Centre, Siberian Branch of the RAS, using hybridization techniques with subsequent selection. The cultivars used as source material for hybridization were ‘Tayoznik’ (Narym Agricultural Station, Tomsk Province) and ‘Orion’ (Siberian Research Institute of Agriculture, Omsk Province).Results. It is a mid-ripening cultivar, with the growing season of 71 to 83 days from sprouting to wax ripeness; its plants are medium-tall (89.6 to 120.2 cm), and resistant to lodging. The average grain yield for the years of study (2014–2019) under the environmental conditions of the northern forest-steppe (Tyumen Province) was 5.88 t/ha (+0.41 t/ha to the reference). The maximum grain yield (7.97 t/ha) was obtained in 2019 at the Lower Tavda Variety Testing Plot, Tyumen Province. The cultivar formed a grain with the test weight of 459.5–527.0 g/l and a low hull content of 22.1–25.1%. The yield of green biomass varied from 31.4 to 47.3 t/ha, depending on the growing conditions, and averaged 37.7 t/ha in 2014–2019 (+7.3 t/ha to the reference). Dry matter harvest averaged 11.76 t/ha (+1.54 t/ha to the reference), ranging from 8.62 to 14.56 t/ha.Conclusion. The new spring oat cultivar ‘Tobolyak’ for universal use has been listed the State Register for Selection Achievements since 2020 and recommended for cultivation in regions 10, 11 and 12 of the Russian Federation
Elements of mathematics in problems. Through olympiads and circles to profession
This is a collection of teaching materials used in several Russian
universities, schools, and mathematical circles. Most problems are chosen in
such a way that in the course of the solution and discussion a reader learns
important mathematical ideas and theories. The materials can be used by pupils
and students for self-study, and by teachers.
This is an abridged pre-copyedit version of the published book submitted with
the permission of the publisher. Each included individual material is
self-contained and ready-for-use. Solutions to problems are not included
intentionally. This collection consolidates updates of several arXiv
submissions, e.g., arXiv:1305.2598.Comment: Edited by A. Skopenkov, M. Skopenkov, A. Zaslavsky. In Russian.
Optimized for printing on A5 paper. Moscow Center for Continuous Mathematical
Education, 2018, 592pp (in Russian
Polymorphism of lipid exchange genes in some populations of South and East Siberia
Lipid metabolism disorders underlie the pathogenesis of a number of diseases. Indigenous peoples of Siberia have a specific genetically determined type of metabolism supporting such lipid blood parameters that favor increased consumption (in comparison with Caucasians) of animal products. At the same time, indigenous Siberian ethnic groups are less susceptible to metabolic diseases. The objective of the presented study was to investigate the allele frequencies of lipid metabolism genes in indigenous populations of Siberia to identify the ethnic features of allele frequency distribution for polymorphic variants in genes CETP (G1264A, rs5882), LPL (C1791G, rs328) and FTO (C83401A, rs8050136) in the samples taken from Buryats, Teleuts and Russians of Eastern Siberia, and to compare them with data on world populations. Samples of the Eastern (N = 132) and Western (N = 278) Buryats, Teleuts (N = 120), Russians (N = 122) and persons of mixed Buryat-Russian origin (N = 56) were genotyped by real-time PCR using competitive TaqMan-probes. The obtained results have for the first time demonstrated that the CETP and FTO allele frequencies in the Buryat samples are intermediate between European and East Asian populations. Significantly lower incidence of the obesity-assossiated 83401A allele of the FTO gene has been shown in Buryats, compared with Russians, which is consistent with lower susceptibility of the indigenous ethnic groups to metabolic disorders. There have been no population differences in the distribution of LPL gene polymorphic variants associated with dyslipidemia, which means they probably do not contribute to the ethnic characteristics of the lipid profile. The intermediate frequencies of the CETP 1264G and FTO 83401A alleles found in the metis group demonstrate that the metabolic disorders associated with these variants can be rather expected in the descendants of mixed marriages than among Buryats. It has also been demonstrated that Teleuts differ by FTO 83401A allele frequency from some of the European groups and have the lowest detected frequency of the allele CETP 1264G associated with the favorable lipid blood parameters
Dysfunction in Ribosomal Gene Expression in the Hypothalamus and Hippocampus following Chronic Social Defeat Stress in Male Mice as Revealed by RNA-Seq
Chronic social defeat stress leads to the development of anxiety-and depression-like states in male mice and is accompanied by numerous molecular changes in brain. The influence of 21-day period of social stress on ribosomal gene expression in five brain regions was studied using the RNA-Seq database. Most Rps, Rpl, Mprs, and Mprl genes were upregulated in the hypothalamus and downregulated in the hippocampus, which may indicate ribosomal dysfunction following chronic social defeat stress. There were no differentially expressed ribosomal genes in the ventral tegmental area, midbrain raphe nuclei, or striatum. This approach may be used to identify a pharmacological treatment of ribosome biogenesis abnormalities in the brain of patients with "ribosomopathies."
Role of apoptosis genes in aggression revealed using combined analysis of ANDSystem gene networks, expression and genomic data in grey rats with aggressive behavior
Aggressive behavior in animals plays an important role in protecting the territory, offspring, establishing social hierarchical relations, etc. Increased aggression is observed in a number of diseases ( schizophrenia, bipolar disorder, brain degenerative disorders). Neuronal apoptosis is crucial in the maintenance of developmental processes during neurogenesis. Alterations in neuronal apoptosis are observed in aging and neuropathologies accompanied by changes in psychoemo tional state (epilepsy, Alzheimer’s disease, neurotrauma). The expression of key neuronal apoptosis genes (Casp3, Bax and Bcl-xl) in the brain of highly aggressive rats is significantly altered. The aim of this work was to analyze associative networks that describe genetic interactions between genes/proteins involved in neuronal apoptosis, differentially expressed genes and genes with polymorphisms in grey rats with aggressive behavior. Analysis revealed 819 differentially expressed genes in the hypothalamus, ventral tegmental region and periaqueductus Sylvii grey matter in grey rats with aggressive and tame behavior. The Stx1a, Mbp and Th genes have the highest index of betweenness centrality in the associative network of differentially expressed genes. Genome analysis revealed 137 polymorphic genes. Three of them (Lig4, Parp1 and Pigt) were involved in neuronal apoptosis. It was shown that polymorphic and differentially expressed genes were statistically significantly overrepresented among ge nes interacting with neuronal apoptosis genes (p value < 0.01). Three moleculargenetic chains describing connections between polymorphic and neuronal apoptosis genes mediated by differentially expressed genes were reconstructed. Chains included the polymorphic genes Tsc1, Adamts4 and Lgals3, differentially expressed genes Ezr, Acan, Th and 19 neuronal apoptosis genes. It was shown that neuronal apoptosis is closely related to aggressive behavior in animals
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