Tomsk State University, TSU is a public research university located in Siberia, Russia. It was founded in 1880 in Tomsk, Russia, and is the oldest university in Russian Asia. TSU opened in 1888 with only one department, the medical faculty, which separated in 1930, now forms the Siberian State Medical University. At present, there are 23 departments with 23,000 students. TSU is one of the Russian-39, which marks it as an official National Research University and a top-15 Russian Leading universities . Wikipedia.
News Article | May 17, 2017
During an expedition to the Krasnoyarsk Territory, scientists from Tomsk State University and St. Petersburg State University (TSU and SPBU), discovered the remains of a previously unknown mammal - the baidabatyr. The animal belonged to multituberculates, one of the ancient taxa of mammals known from the Middle Jurassic. Their name derives from the structure of their teeth. These animals appeared in the Jurassic period and survived the mass extinction of species at the end of the Cretaceous. Some species of multituberculates became extinct only in the Paleogene. Thus, this clade/group has existed for about 150 million years. - Baidabatyr is a multituberculate mammal. We found only one tooth and immediately realized that the characteristic features of the structure - the number and location of the tubercles - indicate that this is a species previously unknown to science. This is an important find for Western Siberia. - said Stepan Ivantsov, a TSU paleontologist. He clarified that there are no present representatives of this order - they died out about 20 million years ago. - Judging by the structure of the tooth, it was a herbivorous animal, probably it ate seeds. The size of the tooth is a couple of millimeters, which means that the animal was the size of a hamster or slightly larger. The name was composed of the words "bidarka" (kayak) because the type locality can be reached only by kayak and "batyr" as "hero" from the Turkish language. First representatives of this taxon were found in Mongolia, and the name of most species traditionally includes Mongolian word "baatar". We decided to name it in Turkish, because it is one of the local languages - added Stepan Ivantsov. According to the scientist, the find was made on the Bolshoy Kemchug River in the remote taiga. The southeast of Western Siberia in the Early Cretaceous was a refugium: an area where some species of the Jurassic period (about 145 million years ago) were preserved in the Cretaceous - where, they existed for several million years longer than on the rest of the planet. The remains of the animal were discovered in the summer of 2015. However, before the scientists officially announced their discovery, they had to describe the find and publish an article in a leading international journal.
News Article | April 20, 2017
Humans and mammoths have a lot in common, including diseases. Scientists have found evidence woolly mammoths suffered from bone problems similar to what humans experience today, a study in Quaternary International found. And the bone diseases, such as osteoporosis and osteofibrosis, were common among the extinct mammals — appearing in almost half of the samples from the enormous species. Read: How Evolution Killed Woolly Mammoths (It Was Devastating) One of the bone conditions, referred to as “rice grain,” is “a fragment of bone or cartilaginous tissue that is located freely in the joint cavity,” Tomsk State University said in a statement about the research. Like it does in people, that would cause severe pain and restrict the animal’s movement, making it “an easy target for predators.” The bone destruction, and thus the species’ extinction, is probably related to “mineral starvation” — a deficiency that would lead to a metabolic disorder. Author Sergey Leshchinskiy, a paleontologist at TSU, analyzed the remains of more than 1,500 mammoths 12,000 to 13,000 years old, the study said. They came from the Berelyokh site in Russia’s Siberia, and the researcher wrote that the site “reflects the terminal stage of the last mass extinction of large mammals.” Bone diseases were probably not the only issue these late mammoths would have had — evolution was not kind to this famously tragic species. Recent research has shown that the last woolly mammoths on Earth had probably lost their sense of smell, had an irritated stomach and had translucent hair. The information came from comparing the genes of mammoths that lived during the species’ peak to genes of mammoths during their final years. There were so few mammoths toward the end that they would have become inbred, helplessly passing on bad genes. The hair would have been the most visible change, as woolly mammoths were known for stiff coats that protected them from the elements. But toward the end, they would have had fur like satin. Two Extinct Reptiles Are Actually the Same Thing Scientists Use Skull and Bones to Recreate Ancient Woman’s Face
Agency: European Commission | Branch: FP7 | Program: CP-IP | Phase: NMP.2011.4.0-1 | Award Amount: 17.87M | Year: 2012
The ExoMet proposal revolves around innovative liquid metal engineering and the application of external physical fields, in order to significantly influence the microstructures and properties of light alloys, such as aluminium and magnesium. Three types of external fields will be explored, namely: electromagnetic, ultrasonic and intensive mechanical shearing. To meet the future EU challenges of lightweighting and pollution reduction, especially relevant in transportation, it is necessary to improve the castability of light alloys, to enhance grain and eutectic refinement in monolithic alloys, and to develop new high-strength nanocomposites using nano-reinforcers which have only recently become available. Significant mechanical property improvements are foreseen in ExoMet - including 50% increases in tensile strength and ductility, as well as creep resistance up to 300-350 degC (currently limited to about 200 degC in Al and Mg alloys). This applies to both shape castings and wrought products like extruded profiles, bar, cable, sheet and plate. Manufacturing scale-up will be tackled in ExoMet, using a variety of techniques such as low and high-pressure die casting, sand casting, investment casting, differential-presssure casting, twin-roll casting, ultrasound-assisted casting and twin-shear casting. The application of external fields to these industrial techniques is novel and would bring about major savings in energy, scrap and processing cost. Having developed the field-enabled processes and produced high-quality light alloys and nanocomposites, the next stage of ExoMet will be prototypying and the assessment of industrial applications in four selected commercial sectors: (i) automotive powertrain and chassis, (ii) aircraft and aero-engine structures, (iii) space satellite and rockets, and (iv) high-strength high-conductivity Al electrical cabling. Computer modelling, rig-testing, standardisation, life-cycle analysis and patenting will also be undertaken.
Sharapov A.A.,Tomsk State University
International Journal of Modern Physics A | Year: 2014
The concept of Lagrange structure allows one to systematically quantize the Lagrangian and non-Lagrangian dynamics within the path-integral approach. In this paper, I show that any Lagrange structure gives rise to a covariant Poisson bracket on the space of solutions to the classical equations of motion, be they Lagrangian or not. The bracket generalize the well-known Peierls' bracket construction and make a bridge between the path-integral and the deformation quantization of non-Lagrangian dynamics. © World Scientific Publishing Company.
Moshin P.Y.,Tomsk State University |
Reshetnyak A.A.,Tomsk State Pedagogical University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2014
We continue the study of finite BRST-antiBRST transformations for general gauge theories in Lagrangian formalism initiated in , with a doublet λa, a=1, 2, of anticommuting Grassmann parameters, and find an explicit Jacobian corresponding to this change of variables for constant λa. This makes it possible to derive the Ward identities and their consequences for the generating functional of Green's functions. We announce the form of the Jacobian (proved to be correct in ) for finite field-dependent BRST-antiBRST transformations with functionally-dependent parameters, λa=saΛ, induced by a finite even-valued functional Λ(ϕ, π, λ) and by the generators sa of BRST-antiBRST transformations, acting in the space of fields ϕ, antifields ϕa *ϕ and auxiliary variables πa, λ. On the basis of this Jacobian, we present and solve a compensation equation for Λ, which is used to achieve a precise change of the gauge-fixing functional for an arbitrary gauge theory. We derive a new form of the Ward identities, containing the parameters λa, and study the problem of gauge-dependence. The general approach is exemplified by the Freedman-Townsend model of a non-Abelian antisymmetric tensor field. © 2014 The Authors.
Samsonov B.F.,Tomsk State University
Journal of Physics A: Mathematical and Theoretical | Year: 2011
Using techniques of supersymmetric quantum mechanics, scattering properties of Hermitian Hamiltonians, which are related to non-Hermitian ones by similarity transformations, are studied. We have found that the scattering matrix of the Hermitian Hamiltonian coincides with the phase factor of the non-unitary scattering matrix of the non-Hermitian Hamiltonian. The possible presence of a spectral singularity in a non-Hermitian Hamiltonian translates into a pronounced resonance in the scattering cross section of its Hermitian counterpart. This opens a way for detecting spectral singularities in scattering experiments; although a singular point is inaccessible for the Hermitian Hamiltonian, the Hamiltonian feels the presence of the singularity if it is close enough. We also show that cross sections of the non-Hermitian Hamiltonian do not exhibit any resonance behavior and explain the resonance behavior of the Hermitian Hamiltonian cross section by the fact that the corresponding scattering matrix, up to a background scattering matrix, is a square root of the BreitWigner scattering matrix. © 2011 IOP Publishing Ltd.
Samsonov B.F.,Tomsk State University
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2013
One of the simplest non-Hermitian Hamiltonians, first proposed by Schwartz in 1960, that may possess a spectral singularity is analysed from the point of view of the non-Hermitian generalization of quantum mechanics. It is shown that the η operator, being a second-order differential operator, has supersymmetric structure. Asymptotic behaviour of the eigenfunctions of a Hermitian Hamiltonian equivalent to the given non-Hermitian one is found. As a result, the corresponding scattering matrix and cross section are given explicitly. It is demonstrated that the possible presence of a spectral singularity in the spectrum of the non-Hermitian Hamiltonian may be detected as a resonance in the scattering cross section of its Hermitian counterpart. Nevertheless, just at the singular point, the equivalent Hermitian Hamiltonian becomes undetermined. © 2013 The Author(s) Published by the Royal Society. All rights reserved.
Sharapov A.A.,Tomsk State University
International Journal of Modern Physics A | Year: 2015
We introduce the concept of a variational tricomplex, which is applicable both to variational and nonvariational gauge systems. Assigning this tricomplex with an appropriate symplectic structure and a Cauchy foliation, we establish a general correspondence between the Lagrangian and Hamiltonian pictures of one and the same (not necessarily variational) dynamics. In practical terms, this correspondence allows one to construct the generating functional of a weak Poisson structure starting from that of a Lagrange structure. As a byproduct, a covariant procedure is proposed for deriving the classical BRST charge of the BFV formalism by a given BV master action. The general approach is illustrated by the examples of Maxwell's electrodynamics and chiral bosons in two dimensions. © 2015 World Scientific Publishing Company.
Arkatova L.A.,Tomsk State University
Catalysis Today | Year: 2010
Dry reforming of methane was studied over the systems on the base of Ni3Al and Ni3Al + 5%Mo in the temperature range 600-900 °C. The materials have been prepared by self-propagating high temperature synthesis and characterized by XRD (in situ and ex situ), DTA-TG, SEM + EDX, HRTEM + EDS and XPS. The formation of Mo2C phase was observed at moderate Mo content (5-10 wt.%), which corresponds to a much improved catalytic activity and stability under the severe carbon dioxide reforming conditions. The structure and morphology of different types of carbon deposits obtained on Ni3Al and Ni3Al + 5%Mo catalysts were investigated. The results indicated that the addition a low amount of Mo to Ni3Al led to a decrease in carbon deposition. It is shown that Ni3Al + 5%Mo is promising catalyst for dry reforming of methane with carbon dioxide. © 2010 Elsevier B.V. All rights reserved.
Ryabova G.O.,Tomsk State University
Monthly Notices of the Royal Astronomical Society | Year: 2012
Asteroid (3200) Phaethon is the supposed parent body for the Geminid meteoroid stream and previously it has never shown any trace of activity. However, it doubled its brightness unexpectedly and sharply in 2009 June. This short outburst could imply that an ejection of dust particles had taken place. We have modelled this dust ejection and the subsequent evolution of the meteoroid swarm, with the aim of determining whether the dust could be observed as meteors on Earth in the near future. We also wish to determine whether the outburst activity can be distinguished from the activity of the main shower. We have found that the model dust swarm is slowly approaching Earth and that it will enter the Earth's influence sphere (<0.03au) in 2014. The minimum distance between particles and the Earth will be at least 0.015au until 2050. Therefore, it will be possible to observe the resulting meteors, but the probability of the event is small. The outburst in the Geminid's activity as a result of this swarm might take place at λ ⊙= 262°.5 (i.e. after the main Geminid's maximum). To exceed the usual level of activity, the mass of the 2009 swarm should exceed ~10 8kg. The radiation area of the model outburst meteors is a small spot: α≈ 114°.65 ± 2°5, δ≈ 32°.7 ± 0°.1. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.