42 results match your criteria: "Tomsk State Pedagogical University[Affiliation]"

The purpose of this study was to investigate the sleep characteristics, circadian rhythms, behavior, and postnatal development of children with and without language difficulties (LDs) and the association of these variables with melatonin-containing food (FMT) consumption. The study involved parents who anonymously and voluntarily provided their children's personal data and assessed LDs, bedtime, meal timing, behavioral problems, gross motor skill development, and FMT consumption. Multiple regression analysis was used to analyze the associations between study variables.

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For the first time, the two factors (the number of sites in the transition state and the nature of the catalytically active species) that affect the energy barriers ( and Δ) in atmospheric aldehyde reactions are proposed. The contribution of each factor to the energy barriers of the ammonization and amination stages, dehydration, and intramolecular hydrogen transfer is studied using the example of the acetaldehyde and glyoxal interactions with ammonia in aqueous solution. A regular decrease in energy barriers is observed in a series of 4-, 6-, and 8-membered transition states (TSs) regardless of the nature of the catalytically active species and their numbers.

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Polydentate ligands are used for thermodynamic stabilization of tetrylenes-low-valent derivatives of Group 14 elements (E = Si, Ge, Sn, Pb). This work shows by DFT calculations how the structure (the presence or absence of substituents) and type (alcoholic, Alk, or phenolic, Ar) of tridentate ligands 2,6-pyridinobis(1,2-ethanols) []H and 2,6-pyridinobis(1,2-phenols) []H (R = H, Me) may affect the reactivity or stabilization of tetrylene, indicating the unprecedented behavior of Main Group elements. This enables the unique control of the type of the occurring reaction.

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The article considered the solution of the inverse problem of chemical kinetics of the analysis of experimental data of a thermogravimetric experiment at a constant sample heating rate. The fitting method for identifying the parameters of a kinetic triplet using the integral method for a model of a solid-state reaction based on the modified Arrhenius equation is described. The effectiveness of the proposed approach was confirmed by solving test cases for low, medium, and high rates of material conversion.

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Derivatives of main group elements containing element-element bonds are characterized by unique properties due to σ-conjugation, which is an attractive subject for investigation. A novel series of digermanes, ArGe-Ge(SiMe), containing aryl (Ar = -CHMe (), -CHF (), CF ()) and trimethylsilyl substituents, was synthesized by the reaction of germyl potassium salt, [(MeSi)GeK*THF], with triarylchlorogermanes, ArGeCl. The optical and electronic properties of such substituted oligoorganogermanes were investigated spectroscopically by UV/vis absorption spectroscopy and theoretically by DFT calculations.

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The most thermodynamically and kinetically favorable pathways for the formation of 2-methylimidazole (2MI) in the reaction of glyoxal and acetaldehyde with ammonia in aqueous solution have been determined. The formation of 2MI proceeds through a number of successive intermediates of acyclic and cyclic structures, and the most favorable route (thermodynamically and kinetically) for the formation of the imidazole ring is the condensation of amine intermediates, in contrast to the existing concepts of imine structures. The limiting stage is the stage of cyclization involving the intramolecular attack by the amino group of the precyclic intermediate on the carbon atom bound to the hydroxyl group with the simultaneous release of a water molecule according to the S2 mechanism.

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Probing the explanation of the muon (g-2) anomaly and thermal light dark matter with the semi-visible dark photon channel.

Eur Phys J C Part Fields

October 2021

Departamento de Ciencias Físicas, Universidad Andres Bello, Sazié 2212, Piso 7, Santiago, Chile.

We report the results of a search for a new vector boson ( ) decaying into two dark matter particles of different mass. The heavier particle subsequently decays to and an off-shell Dark Photon . For a sufficiently large mass splitting, this model can explain in terms of new physics the recently confirmed discrepancy observed in the muon anomalous magnetic moment at Fermilab.

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We present climate-dependent changes in the high-mountain forest ecotone, old-growth forests, alpine phytocenoses, and deglaciated forelands in the Aktru glacial basin (Altai Republic, Russia). A number of independent sources (variations in upper treeline altitude, dendrochronological data, analysis of lacustrine sediments and botanical and geographical studies linked with the dynamics of glacial-dammed lakes in the Chuya and Kurai intermountain depressions) suggest Holocene temperatures reached about 4 °C higher than today. Unlike the European Alps, glaciers in the continental Altai Mountains disappeared before forming again.

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Changes in climate, land-use and pollution are having disproportionate impacts on ecosystems and biodiversity of arctic and mountain ecosystems. While these impacts are well-documented for many areas of the Arctic and alpine regions, some isolated and inaccessible mountain areas are poorly studied. Furthermore, even in well-studied regions, assessments of biodiversity and species responses to environmental change are biased towards vascular plants and cryptogams, particularly bryophytes are far less represented.

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Biological diversity is the basis for, and an indicator of biosphere integrity. Together with climate change, its loss is one of the two most important planetary boundaries. A halt in biodiversity loss is one of the UN Sustainable Development Goals.

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We performed a search for a new generic X boson, which could be a scalar (S), pseudoscalar (P), vector (V), or an axial vector (A) particle produced in the 100 GeV electron scattering off nuclei, e^{-}Z→e^{-}ZX, followed by its invisible decay in the NA64 experiment at CERN. No evidence for such a process was found in the full NA64 dataset of 2.84×10^{11} electrons on target.

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Peatlands cover 3% of the land, occur in 169 countries, and have-by sequestering 600 Gt of carbon-cooled the global climate by 0.6 °C. After a general review about peatlands worldwide, this paper describes the importance of the Great Vasyugan Mire and presents suggestions about its protection and future research.

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Hunting down the X17 boson at the CERN SPS.

Eur Phys J C Part Fields

December 2020

Departamento de Ciencias Físicas, Universidad Andres Bello, Sazié 2212, Piso 7, Santiago, Chile.

Recently, the ATOMKI experiment has reported new evidence for the excess of events with a mass 17 MeV in the nuclear transitions of He, that they previously observed in measurements with Be. These observations could be explained by the existence of a new vector boson. So far, the search for the decay with the NA64 experiment at the CERN SPS gave negative results.

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Effect of Humic Acids from Lowland Peat on Endurance of Rats in Forced Swim Test in Relation to Serum Lactate and Corticosterone.

Bull Exp Biol Med

October 2020

E. D. Goldberg Research Institute of Pharmacology and Regenerative Medicine, Tomsk National Research Medical Center, Russian Academy of Sciences, Tomsk, Russia.

The study substantiated the possibility of using peat humic acids for improving endurance during extreme physical exertion. The mature outbred Wistar rats weighing 200-250 g (n=40) were subjected to forced swim test until complete exhaustion. The humic acids (1%) were administered intragastrically (0.

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Search for Axionlike and Scalar Particles with the NA64 Experiment.

Phys Rev Lett

August 2020

Departamento de Ciencias Físicas, Universidad Andres Bello, Sazié 2212, Piso 7, Santiago, Chile.

We carried out a model-independent search for light scalar (s) and pseudoscalar axionlike (a) particles that couple to two photons by using the high-energy CERN SPS H4 electron beam. The new particles, if they exist, could be produced through the Primakoff effect in interactions of hard bremsstrahlung photons generated by 100 GeV electrons in the NA64 active dump with virtual photons provided by the nuclei of the dump. The a(s) would penetrate the downstream HCAL module, serving as a shield, and would be observed either through their a(s)→γγ decay in the rest of the HCAL detector, or as events with a large missing energy if the a(s) decays downstream of the HCAL.

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Hydroxyapatites modified with metal ions are the main inorganic components of bone tissue and are approved for use as components for biocomposites and coatings for surgical implants. This study examined prototypes of functional materials for bone implants based on hydroxyapatite modified with zinc ions. Zinc-modified hydroxyapatite was composed and synthesized.

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Dark Matter Search in Missing Energy Events with NA64.

Phys Rev Lett

September 2019

Universidad Técnica Federico Santa María, 2390123 Valparaíso, Chile.

A search for sub-GeV dark matter production mediated by a new vector boson A^{'}, called a dark photon, is performed by the NA64 experiment in missing energy events from 100 GeV electron interactions in an active beam dump at the CERN SPS. From the analysis of the data collected in the years 2016, 2017, and 2018 with 2.84×10^{11} electrons on target no evidence of such a process has been found.

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Aim: to assess the role of human granulocytic anaplasmosis (HGA) caused by Anaplasma phagocytophilum in the induction of cytogenetic damage of spermatozoa and karyopathological abnormalities of urothelial cells depending on the polymorphism of the gene of enzyme, DNA ligase IV.

Material And Methods: A total of 129 male patients with HGA and 84 otherwise healthy donors were examined. The samples of both semen and urothelial cells were obtained from each individuals for microscopic analysis.

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The cardioprotective and inotropic effects of standardized active natural substance based on high-molecular-weight compounds of humic origin were studied on the model of global ischemia (40 min) and reperfusion of isolated perfused rat heart. Preventive administration of the test substance (0.1 mg/ml) before ischemia/reperfusion modeling reduced reperfusion contracture and necrotic death of cardiomyocytes and promoted recovery of myocardial contractility.

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Scientific Ethos and Foundations of Conscious Activity.

Integr Psychol Behav Sci

March 2020

Tomsk State Pedagogical University, 634061, Tomsk, Kievskaya St. 60, Russia.

Clarification of the scientific ethos provides the opportunity to reconstruct the foundations on which the conscious activity in science is based. Contemporary scientific society does not fully recognize this metaphysical issue because of the domination of the power of naturalistic argument. The ethos of science does not show its natural embodiment; it is the complex of social and psychological norms, which rules each scientist unconsciously.

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In this article, we report and discuss the results obtained from a survey of plants, microorganisms (bacteria and fungi), and soil elements along a chronosequence in the first 600 m of the Maliy Aktru glacier's forefront (Altai Mountains, Russia). Many glaciers of the world show effects of climate change. Nonetheless, except for some local reports, the ecological effects of deglaciation have been poorly studied and have not been quantitatively assessed in the Altai Mountains.

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Background: Borrelia infection is known to develop as a result of the bites of the ixodid ticks while the extremely difficult working conditions and low temperatures contribute to the development of chronic gonosteoarthritis (CGA) associated with ixodid tick-borne borreliosis (ITB) in the residents of the northern part of Siberia.

Aim: The objective of the present study was to elucidate the frequency of occurrence of the synovial cells in the knee joints exhibiting the cytogenetic abnormalities with special reference to trisomy of chromosome 7 and the glutathione-S-transferase (GSTM1) gene polymorphism in the residents of the northern part of Siberia presenting with Lyme borreliosis (LB) whose genotype contains some alleles of the GSTM1 gene before and after the treatment of LB-associated CGA with the use of the radon bath therapy. The secondary objective was to compare the respective characteristics and the results of the treatment with those in the patients with post-traumatic gonosteoarthritis (PTGA) and to evaluate the influence of the above abnormalities on the severity of CGA.

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Search for a Hypothetical 16.7 MeV Gauge Boson and Dark Photons in the NA64 Experiment at CERN.

Phys Rev Lett

June 2018

Universidad Técnica Federico Santa María, 2390123 Valparaíso, Chile.

We report the first results on a direct search for a new 16.7 MeV boson (X) which could explain the anomalous excess of e^{+}e^{-} pairs observed in the excited ^{8}Be^{*} nucleus decays. Because of its coupling to electrons, the X could be produced in the bremsstrahlung reaction e^{-}Z→e^{-}ZX by a 100 GeV e^{-} beam incident on an active target in the NA64 experiment at the CERN Super Proton Synchrotron and observed through the subsequent decay into a e^{+}e^{-} pair.

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Here we analyse a particular type of () gravity, the so-called exponential gravity which includes an exponential function of the Ricci scalar in the action. Such a term represents a correction to the usual Hilbert-Einstein action. By using Supernovae Ia, Barionic Acoustic Oscillations, Cosmic Microwave Background and () data, the free parameters of the model are well constrained.

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We studied the involvement of the autonomic nervous system in the antiarrhythmic effect of intermittent hypobaric hypoxia modeled by daily placing the rats into an altitude chamber at 405 mm Hg (5000 m above sea level). The antiarrhythmic effect of hypoxia was observed on the model of acute coronary occlusion/reperfusion in vivo, but not during simulation of total ischemia/reperfusion of the isolated myocardium. Intravenous injection of ganglionic blocker hexamethonium (30 mg/kg) 15 min prior to in vivo coronary occlusion modeling abolished the antiarrhythmic effect of intermittent hypobaric hypoxia, which suggests that this effect is mediated via activation of the autonomic nervous system.

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