166 results match your criteria: "Peter the Great Saint Petersburg Polytechnic University[Affiliation]"

The review considers various aspects of myocardium aging in normal and dilated cardiomyopathy (DC). There is a partial fibrosis of the heart tissue due to accumulation of collagen type 1, and accumulation of amyloid during normal aging. Men myocardial aging is accompanied by loss of cardiomyocytes and increased volume of the remaining cells, whereas in women this effect is absent.

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The review has described melatonin as a prognostic marker of invasive and non-invasive diagnostic of organism aging time and age-related pathology. Decreasing of melatonin level in buccal cells has correlated with patient age. Melatonin level in patients with Alzheimer disease has decreased.

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The review is devoted to an actual problem of cosmetics in gerontology, one of molecular aspects of skin aging. Cell renewal processes slow down with aging, and the proliferation apoptosis ratio shifts towards cell death. One of the most pivotal apoptotic markers is the transcription factor p53.

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Fluorescence of thioflavin T (ThT) is a proven tool for amyloid fibrils study. The correct model of ThT binding to fibrils is crucial to clarify amyloid fibrils structure and mechanism of their formation. Although there are convincing evidences that ThT has molecular rotor nature, implying it's binding to fibrils in monomer form, speculations concerning ThT binding to fibrils in aggregated forms appear in literature so far.

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Casimir free energy of dielectric films: classical limit, low-temperature behavior and control.

J Phys Condens Matter

July 2017

Central Astronomical Observatory at Pulkovo of the Russian Academy of Sciences, Saint Petersburg, 196140, Russia. Institute of Physics, Nanotechnology and Telecommunications, Peter the Great Saint Petersburg Polytechnic University, Saint Petersburg, 195251, Russia.

The Casimir free energy of dielectric films, both free-standing in vacuum and deposited on metallic or dielectric plates, is investigated. It is shown that the values of the free energy depend considerably on whether the calculation approach used neglects or takes into account the dc conductivity of film material. We demonstrate that there are material-dependent and universal classical limits in the former and latter cases, respectively.

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SEM and AFM Studies of Two-Phase Magnetic Alkali Borosilicate Glasses.

ScientificWorldJournal

August 2017

International Laboratory of High Magnetic Fields and Low Temperatures, Gajowicka 95, 53-421 Wroclaw, Poland.

The morphology and composition of four types of two-phase alkali borosilicate glasses with magnetic atoms prepared by inductive melting have been studied. The results of scanning electron microscopy point to uniform distribution of Na, Si, and O atoms in these samples while magnetic iron atoms form ball-shaped agglomerates. The magnetic properties of these agglomerates have been confirmed by magnetic force microscopy.

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Antiferroelectric lead zirconate is the key ingredient in modern ferroelectric and piezoelectric functional solid solutions. By itself it offers opportunities in new-type non-volatile memory and energy storage applications. A highly useful and scientifically puzzling feature of this material is the competition between the ferro- and antiferroelectric phases due to their energetic proximity, which leads to a challenge in understanding of the critical phenomena driving the formation of the antiferroelectric structure.

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Alzheimer's disease (AD) is a progressive neurodegenerative disorder of elderly and old age people. For intravital diagnosis of the expression of signaling molecules - AD markers, cerebrospinal fluid (CSF) and peripheral tissues are used: lymphocytes and blood platelets, buccal and olfactory epithelium, skin fibroblasts. There are several changes in the production of hyper phosphorylated form of τ-protein, BACE1 and peptide Аβ42 in CSF in case of AD, but CSF taking may have a number of side effects.

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In this study, we have shown that substitution of chloride ligand for imidazole (Im) ring in the cyclometalated platinum complex Pt(phpy)(PPh)Cl (1; phpy, 2-phenylpyridine; PPh, triphenylphosphine), which is nonemissive in solution, switches on phosphorescence of the resulting compound. Crystallographic and nuclear magnetic resonance (NMR) spectroscopic studies of the substitution product showed that the luminescence ignition is a result of Im coordination to give the [Pt(phpy)(Im)(PPh)]Cl complex. The other imidazole-containing biomolecules, such as histidine and histidine-containing peptides and proteins, also trigger luminescence of the substitution products.

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Understanding software engineers' behaviour plays a vital role in the software development industry. It also provides helpful guidelines for teaching and learning. In this article, we conduct a study of the extrafoveal vision and its role in information processing.

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Comment on "Lifshitz-Matsubara sum formula for the Casimir pressure between magnetic metallic mirrors".

Phys Rev E

August 2016

Central Astronomical Observatory at Pulkovo of the Russian Academy of Sciences, Saint Petersburg 196140, Russia and Institute of Physics, Nanotechnology and Telecommunications, Peter the Great Saint Petersburg Polytechnic University, St. Petersburg 195251, Russia.

Recently Guérout et al. [Phys. Rev.

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We present a theory of electron scattering on a magnetic Skyrmion for the case when the exchange interaction is moderate so that the adiabatic approximation and the Berry phase approach are not applicable. The theory explains the appearance of a topological Hall current in the systems with magnetic Skyrmions, the special importance of which is its applicability to dilute magnetic semiconductors with a weak exchange interaction.

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Classification algorithms based on different forms of support vector machines (SVMs) for dealing with interval-valued training data are proposed in the paper. L2-norm and L∞-norm SVMs are used for constructing the algorithms. The main idea allowing us to represent the complex optimization problems as a set of simple linear or quadratic programming problems is to approximate the Gaussian kernel by the well-known triangular and Epanechnikov kernels.

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The paper presents the latest literature data on the structure and functions of «protein of juvenility» - CCL11 and «protein of senility» - GDF11. Chemokine CCL11 injected to young animals has been shown to lead to degenerative changes in the central nervous system (CNS), disturb cognitive functions and impede tissue regeneration. CCL11 concentration increases dramatically in schizophrenia, Alzheimer's disease, neuro-inflammatory disorders, cerebral malaria, drug addiction, as well as in atherosclerosis, periodontal disease, macular degeneration, cancer and other pathologies.

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Peptide KED (Lys-Glu-Asp) has vasoprotective effects and is effective substance in treatment of of atherosclerosis and other cardio-vascular disorders in elderly people. One of the probable mechanisms of biological activity of this peptide is epigenetic genes regulation. These genes can coding proteins, which are markers of endothelium functional activity.

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Native globular actin has a thermodynamically unstable quasi-stationary structure with elements of intrinsic disorder.

FEBS J

February 2016

Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, St Petersburg, Russia.

The native form of globular actin, G-actin, is formed in vivo as a result of complex post-translational folding processes that require ATP energy expenditure and are assisted by the 70 kDa heat shock protein, prefoldin and chaperonin containing TCP-1. G-actin is stabilized by the binding of one ATP molecule and one Ca(2+) ion (or Mg(2+) in vivo). Chemical denaturants, heating or Ca(2+) removal transform native actin (N) into 'inactivated actin' (I), a compact oligomer comprising 14-16 subunits.

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