Petrozavodsk, Russia

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Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: HEALTH-2007-2.4.3-1 | Award Amount: 7.70M | Year: 2008

Preliminary data indicate that there is a strong association between the incidence of immune-mediated diseases and improving standard of living and hygiene. One of the steepest gradient in standard of living worldwide is present at the border between Russian Karelia and Finland with a sevenfold difference in the gross national product, while Estonia represents a country in rapid transition. These three populations comprise a living laboratory providing a unique possibility to test the hygiene hypothesis in the development of immune-mediated diseases. The incidence of type 1 diabetes (T1D) is six times lower in Russian Karelia than in Finland, whereas there are very limited differences in the frequency of risk HLA genotypes in the background population. This proposal aims at comparing (i) the frequency of beta-cell autoimmunity and other organ-specific autoantibodies; (ii) the frequency of IgE-specific sensitisation and signs of allergy; (iii) the frequency of various infections; (iv) the gut microbial flora; and (v) dietary intake in young children between the three populations. The birth cohort arm of the study aims at (i) delineating the ontogeny of the immune system by using modern tools of functional genomics; (ii) comparing the functional characteristics of regulatory T cells; (iii) characterising the gut microbial colonisation in infants; (iv) assessing the timing of exposure to foreign proteins in infancy (v) defining the interrelations between dietary factors, gut microbial flora and acute microbial infections. The objectives will be approached by studying 1600 children at the age of 3 and 5 years and by observing a birth cohort comprising about 320 subjects with HLA-conferred susceptibility to autoimmunity from birth up to the age of 3 years in each country. This proposal is expected to provide new data on the reasons and mechanisms behind the increasing rates of T1D and other immune-mediated diseases seen in most developed countries after World War II.


Singh V.K.,Bundelkhand University | Slabunov A.,Petrozavodsk State University
International Geology Review | Year: 2015

Analysis of 3.3 Ga tonalite-trondhjemite-granodiorite (TTG) series granitoids and greenstone belt assemblages from the Bundelkhand craton in central India reveal that it is a typical Archaean craton. At least two greenstone complexes can be recognized in the Bundelkhand craton, namely the (i) Central Bundelkhand (Babina, Mauranipur belts) and (ii) Southern Bundelkhand (Girar, Madaura belts). The Central Bundelkhand greenstone complex contains three tectonostratigraphic assemblages: (1) metamorphosed basic or metabasic, high-Mg rocks; (2) banded iron formations (BIFs); and (3) felsic volcanics. The first two assemblages are regarded as representing an earlier sequence, which is in tectonic contact with the felsic volcanics. However, the contact between the BIFs and mafic volcanics is also evidently tectonic. Metabasic high-Mg rocks are represented by amphibolites and tremolite-actinolite schists in the Babina greenstone belt and are comparable in composition to tholeiitic basalts-basaltic andesites and komatiites. They are very similar to the metabasic high-Mg rocks of the Mauranipur greenstone belt. Felsic volcanics occur as fine-grained schists with phenocrysts of quartz, albite, and microcline. Felsic volcanics are classified as calc-alkaline dacites, less commonly rhyolites. The chondrite-normalized rare earth element distribution pattern is poorly fractionated (LaN/LuN = 11-16) with a small negative Eu anomaly (Eu/Eu∗ = 0.68-0.85), being characteristic of volcanics formed in a subduction setting. On Rb - Y + Nb, Nb - Y, Rb - Ta + Yb and Ta - Yb discrimination diagrams, the compositions of the volcanics are also consistent with those of felsic rocks formed in subduction settings. SHRIMP-dating of zircon from the felsic volcanics of the Babina belt of the Central Bundelkhand greenstone complex, performed for the first time, has shown that they were erupted in Neoarchaean time (2542 ± 17 Ma). The early sequence of the Babina belt is correlatable with the rocks of the Mauranipur belt, whose age is tentatively estimated as Mesoarchaean. The Central Bundelkhand greenstone complex consists of two (Meso- and Neoarchaean) sequences, which were formed in subduction settings. © 2014 © 2014 Taylor & Francis.


Pergament A.,Petrozavodsk State University | Velichko A.,Petrozavodsk State University
Thin Solid Films | Year: 2010

Vanadium dioxide has various potential applications in electronics due to the metal-insulator transition (MIT). It is known that oxide structures with nanometric dimensions exhibit properties different from bulk oxide materials because of the spatial confinement and the proximity of the substrate. However, in order to integrate VO 2 into the thriving nano-scale electronics, it is necessary to explore the MIT in this material in thin film nano-structures. In this work, it is shown that there is a fundamental dimensional restriction for the transition to occur even for pure epitaxial VO 2 nano-films and nano-wires. This is associated with the fact that any phase transition turns out to be impossible when the system size is decreased below a certain characteristic length d c. This dimension is estimated to be d c ∼ ξ (where ξ is the correlation length, ∼ 2 nm for VO 2), and, on the basis of the available experimental data, it is shown that the transition temperature falls as the characteristic size (film thickness or nano-wire radius) diminishes, though the predicted theoretical limit of 2 nm is not still experimentally achieved by now. Experimental results concerning the dependence of the threshold voltage on the film thickness at MIT-induced switching in VO 2 based sandwich structures are presented. Finally, the comparison of the authors' experimental data with the literature data, as well as with the analogous features of superconducting phase transitions, is carried out. © 2009 Elsevier B.V. All rights reserved.


Pergament A.,Petrozavodsk State University
Phase Transitions | Year: 2010

On the basis of the Ashcroft empty core model potential, the equation for the constant of Coulomb interaction in the theory of excitonic insulator is modified. It is shown that in this case the dependence of the energy gap width on the charge carrier density obeys the Mott criterion in the limit of low densities. The conformity of the theory with some experimental data concerning metal-insulator phase transitions in doped semiconductors and transition metal compounds is discussed. © 2010 Taylor & Francis.


Here we describe GATO (gravity, age, thermoregulation, and oxygenation) hypothesis (or a "Baby Astronaut" hypothesis) which we suggest to explain synergistic effect of these factors on the motor system. Taken separately, microgravity (in spaceflight, G ∼ 0), the early age, heat and hypoxia exert identical effect on the motor system. We posit that synergy of these factors originate from their synchronicity during intrauterine immersion (analog microgravity) of the fetus in warm hypoxic condition. We further postulate three successive motor adaptive strategies, driven lifelong by gravity as the key factor. The first by age, fetal/microgravity (FM)-strategy, induced by the intrauterine immersion of the fetus, is based on domination of fast type muscle fibers. After birth, thought to be analog for landing from orbit, newborn is subjected to combined influence of cooler ambient temperature, normoxia, and 1G Earth gravity, which cooperatively form a slower GE-strategy. Eventually, healthy ageing results in further domination of slow type muscle fibers that forms the slowest (SL)-strategy. Our hypothesis implies that specific sensory conditions may substitute for each other owing to their synergistic action on the motor system. According to GATO hypothesis heating and hypoxia may be considered as "pro-microgravity" factors, while cold and hyperoxia - as "pro-gravity" ones. As such, cold may act as a partial "surrogate" for gravity, estimated as ∼0.2. G. That may have potential to elaborate countermeasures for muscle atrophy in astronauts either on-board in long-term spaceflight or for post-flight rehabilitation. Based on GATO hypothesis, predictions on muscle remodeling caused by illumination, sound/noise, and gravidity are discussed. © 2012 Elsevier Ltd.


Korzun D.,Petrozavodsk State University
Communications in Computer and Information Science | Year: 2016

Smart spaces define a development approach to creation of service-oriented information systems for computing environments of the Internet of Things (IoT). Semantic-driven resource sharing is applied to make fusion of the physical and information worlds. Knowledge from both worlds is selectively encompassed in the smart space to serve for users’ needs. In this paper, we consider several principles of the smart spaces approach to semantic-driven design of service-oriented information systems. The developers can apply these principles to achieve such properties as (a) involvement for service construction many surrounding devices and personal mobile devices of the user, (b) use of external Internet services and data sources for enhancing the constructed services, (c) information-driven programming of service construction based on resource sharing. The principles are derived from our experience on the software development for such application domains as collaborative work, e-tourism, and mobile health. © Springer International Publishing Switzerland 2016.


Volkov A.S.,Petrozavodsk State University
Signal Processing | Year: 2015

With a growth of the popularity of wireless sensor networks it has became obvious that Bayesian filter is most commonly used method for the sensor localization. The multiple sensors in one device allow to build different variations of the filter through the definition of the components of Bayesian rule. This paper presents a localization algorithm that is based on Bayesian filter and an attempt to evaluate the accuracy of the algorithm for nanoLOC technology. Empirical probability density functions for two Non-Line of Sight (NLOS) cases and different mobile object movement models have been used in the algorithm. The usage of extreme variants of the movement model allows to estimate the lower and upper bounds of the localization algorithm accuracy. Any movement sensor data incorporated into the algorithm produces the algorithm variant where accuracy is within the bounds. Also, the paper presents a technique for recovering the probability density function of distance overestimates from biased measurements and proposes relative accuracy estimate based on the least squares method. The estimate can be used instead of Cramer-Rao lower bound when there is no analytical probability density function. © 2014 Elsevier B.V. All rights reserved.


Bogoiavlenskaia O.,Petrozavodsk State University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015

This paper investigates discrete random process describing behavior of the Additive Increase Multiplicative Decrease algorithm of networking Transmission Control Protocol (TCP). We use the sequence of TCP rounds with no data loss events to define the end-to-end path data loss behavior. The Markov chain embedded in the random process is described and the theorem on its ergodic property is proved. Further analysis yields the estimates of stationary first and second moments of the congestion window size which are key performance metrics of TCP protocol. © Springer International Publishing Switzerland 2015.


The condition of simulated or real manned spaceflight, i.e. thermally comfortable microgravitation (G∼ 0), is very similar to the intrauterine immersion to the amniotic fluid. Domination of fast muscle fibers and phasic movements forms the fetal strategy to survive in heating, strongly hypoxic, albeit normal for fetus, immersion. In adults, the adaptive response separately to microgravitation, heat stress and hypoxia also shifts muscle fiber properties to faster values. That allows to speculate about specific motor strategy induced by micro-or hypogravitation (fetal/. microgravitation, or FM-strategy).After birth the newborn is subjected to a combined 'sensory attack' of Earth gravitation, cooler ambient temperature and normoxia which is actually hyperoxic for fetus. The process of parturition can be considered as equivalent to cosmonaut's/astronaut's transition from microgravitation back to Earth gravitation (G= 1) during landing. These factors also act simultaneously and constitute another set of sensory inputs with the effect that is opposite to the intrauterine condition. In normal gravitation, comfortable temperature and normoxia decreases the motor unit activity (MU) firing rate to a level, characteristic for the regular Earth condition. In contrast to 'faster' fetal adaptive motor response (microgravitation, heat, hypoxia), the post-natal adult set of conditions (lower, but still normal temperature, normoxia, 1. G gravitation, healthy maturation) may represent the 'Earth' adaptive motor response, or the (gravitation/. Earth, or GE-strategy). The motor system undergoes a second profound remodeling in older people during healthy ageing that results in further domination of slow muscle fibers and slowing down motor unit activity, simulating the condition of hypergravitation (G> 1). Similar slowing adaptive responses are represented by cold and hyperoxia thus forming further motor strategy that could be named as SJ-strategy (after 'slow' and Jupiter - the most massive planet and the only planet with G> 1 in the solar system).These strategies suppose that definite sensory inputs and conditions may substitute each other due to its equivalent action on the motor system. Thus, cold 'sensory attack' may serve as a 'surrogate' for gravitation because these two conditions exert equivalent stimulating action on muscle tone. In that respect long-term mild cooling exposures or shorter severe cold exposures may be considered as a prophylactic countermeasure against hazardous action of weightlessness. Also, combination of cooling sensory intervention with traditional and well- documented interventions (whole body vibration and stimulation of 'support zone' afferents) may elevate their anti-microgravitation efficiency. © 2012 Elsevier Ireland Ltd.


Vinogradova I.,Petrozavodsk State University | Anisimov V.,Nn Petrov Research Institute Of Oncology
Biogerontology | Year: 2013

Effect of light regimens (standard 12:12 light/dark, constant light, natural lightning of the north-west of Russia) and that of melatonin on the development of metabolic syndrome during aging of rats was studied. It was found out that during the process of aging of rats kept in the conditions of the broken rhythm of day and night, different disturbances of metabolism in the form of abdominal obesity, hyperinsulinemia, hypercholesterolemia, hyperglycemia, hyperbetalipoproteinemia and glycosuria occurred. These disturbances can be considered to be metabolic syndrome or the syndrome of insulin resistance. The use of melatonin at night time starting in the rats of 4 month old allowed to decrease the age metabolism disorders in the rats. This fact indirectly proves the insufficiency of this hormone in human in the conditions of natural lighting of the north-west of Russia. © 2013 Springer Science+Business Media Dordrecht.

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