34 results match your criteria: "Saint-Petersburg State Polytechnical University[Affiliation]"
Int J Biomater
November 2017
Institute of Macromolecular Compounds, Russian Academy of Sciences, Bolshoy Pr. 31, Saint-Petersburg 199004, Russia.
Tubular vascular grafts 1.1 mm in diameter based on poly(L-lactide) microfibers were obtained by electrospinning. X-ray diffraction and scanning electron microscopy data demonstrated that the samples treated at = 70°C for 1 h in the fixed state on a cylindrical mandrel possessed dense fibrous structure; their degree of crystallinity was approximately 44%.
View Article and Find Full Text PDFStructure
October 2017
Centre for Data-Intensive Biomedicine and Biotechnology, Skolkovo Institute of Science and Technology, 143026 Moscow, Russia; Bionano Institute, Peter the Great Saint Petersburg State Polytechnical University, Saint Petersburg 195251, Russia; Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA. Electronic address:
TldD and TldE proteins are involved in the biosynthesis of microcin B17 (MccB17), an Escherichia coli thiazole/oxazole-modified peptide toxin targeting DNA gyrase. Using a combination of biochemical and crystallographic methods we show that E. coli TldD and TldE interact to form a heterodimeric metalloprotease.
View Article and Find Full Text PDFRSC Adv
September 2016
Department of Applied Physics , School of Science , Aalto University, P. O. Box 15100 , FI-00076 Espoo , Finland . Email:
Hybrid aerogels consisting of cellulose nanofibers (CNF) and modified few-walled carbon nanotubes (FWCNT) are investigated under cyclic mechanical compression to explore "electrical fatigue". For this purpose the FWCNTs were hydrophilized, thus promoting their aqueous dispersibility to allow FWCNT/CNF hybrid hydrogels, followed by freeze-drying to obtain hybrid aerogels. The optimized composition consisting of FWCNT/CNF 20/80 wt/wt showed conductivity of 10 S cm as promoted due to double percolation, and showed only small changes in electrical and mechanical behaviour upon cycling 100 times.
View Article and Find Full Text PDFJ Synchrotron Radiat
January 2017
Dipartimento di Fisica, Università degli studi di Milano, Via Celoria 16, 20133 Milano, Italy.
In this work the experimental uncertainties concerning electron spin polarization (SP) under various realistic measurement conditions are theoretically derived. The accuracy of the evaluation of the SP of the photoelectron current is analysed as a function of the detector parameters and specifications, as well as of the characteristics of the photoexcitation sources. In particular, the different behaviour of single counter or twin counter detectors when the intensity fluctuations of the source are considered have been addressed, leading to a new definition of the SP detector performance.
View Article and Find Full Text PDFEvol Dev
May 2016
Program in Molecular and Computation Biology, Dornsife College of Letters, Arts, and Sciences, University of Southern California, Los Angeles, CA 90089, USA.
Animal development is the product of distinct components and interactions-genes, regulatory networks, and cells-and it exhibits emergent properties that cannot be inferred from the components in isolation. Often the focus is on the genotype-to-phenotype map, overlooking the process of development that turns one into the other. We propose a move toward micro-evolutionary analysis of development, incorporating new tools that enable cell type resolution and single-cell microscopy.
View Article and Find Full Text PDFRev Sci Instrum
March 2016
Laboratorio TASC, IOM-CNR, S.S. 14 km 163.5, Basovizza, 34149 Trieste, Italy.
ULTRASPIN is an apparatus devoted to the measurement of the spin polarization (SP) of electrons ejected from solid surfaces in a UHV environment. It is designed to exploit ultrafast light sources (free electron laser or laser high harmonic generation) and to perform (photo)electron spin analysis by an arrangement of Mott scattering polarimeters that measure the full SP vector. The system consists of two interconnected UHV vessels: one for surface science sample cleaning treatments, e-beam deposition of ultrathin films, and low energy electron diffraction/AES characterization.
View Article and Find Full Text PDFPhys Rev E
February 2016
Université de Lyon, LaMCoS, INSA-Lyon, CNRS UMR5259, F-69621, France and Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, F-69622 Villeurbanne Cedex, France.
The vibrational properties of model amorphous materials are studied by combining complete analysis of the vibration modes, dynamical structure factor, and energy diffusivity with exact diagonalization of the dynamical matrix and the kernel polynomial method, which allows a study of very large system sizes. Different materials are studied that differ only by the bending rigidity of the interactions in a Stillinger-Weber modelization used to describe amorphous silicon. The local bending rigidity can thus be used as a control parameter, to tune the sound velocity together with local bonds directionality.
View Article and Find Full Text PDFCardiovasc Eng Technol
March 2016
Saint-Petersburg State Polytechnical University, Saint Petersburg, Russia.
Tubular grafts based on nanofibers of copolymer of ε-caprolactam and hexamethylendiaminadipate were obtained by the electrospinning method. The strength of materials based on the dry nanofibers was 6.2 MPa with elongation at break of 133%, or 7.
View Article and Find Full Text PDFInt J Pept
October 2015
FSBI Petersburg Nuclear Physics Institute, NRC Kurchatov Institute, Orlova Roscha, Gatchina 188300, Russia.
Changes in protein conformation can occur both as part of normal protein functioning and during disease pathogenesis. The most common conformational diseases are amyloidoses. Sometimes the development of a number of diseases which are not traditionally related to amyloidoses is associated with amyloid-like conformational transitions of proteins.
View Article and Find Full Text PDFEur J Mass Spectrom (Chichester)
October 2015
Institute for Analytical Instrumentation of RAS, Rizsky pr., 26, St.Petersburg, 190103 Russia. Ioffe Physico-Technical Institute of RAS, Politechnicheskaya, 26, St.Petersburg, 194021, Russia. Saint-Petersburg State Polytechnical University, Politechnicheskaya, 29, St.Petersburg, Russia..
Electrospray ionization with controlled in-source fragmentation and atomization (ERIAD) is promising method for mass-spectrometric elemental analysis. This paper concerns the main analytical features and necessary instrumentation for ERIAD. The method is shown to be effective for more than 70 elements of the periodic table: those that present as cations in a water solution.
View Article and Find Full Text PDFJ Psychosoc Oncol
January 2016
c Laboratory of Biomedical Informatics, Saint Petersburg Institute for Informatics and Automation of Russian Academy of Sciences, Saint Petersburg , Russia.
The goal of the present research is to investigate and analyze possible peculiarities of the psychological state of cancer patients undergoing treatment. Scores characterizing the trait and state anxiety were acquired using the Integrative Anxiety Test from four groups: adults with no appreciable disease, pregnant women, cancer patients examined during the specific antitumor treatment, and cancer patients brought into lasting clinical remission. Statistical analysis of the testing results revealed the bimodal type of the distribution of scores.
View Article and Find Full Text PDFJ Am Chem Soc
July 2015
†Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Unlabelled: Organic solar cells have been regarded as a promising electrical energy source. Transparent and conductive carbon nanotube film offers an alternative to commonly used ITO in photovoltaics with superior flexibility. This communication reports carbon nanotube-based indium-free organic solar cells and their flexible application.
View Article and Find Full Text PDFR Soc Open Sci
October 2014
Department of Theoretical Physics, Kursk State University, Radishcheva st. 33 , Kursk 305000, Russia.
The application of the continuous wavelet transform to the study of a wide class of physical processes with oscillatory dynamics is restricted by large central frequencies owing to the admissibility condition. We propose an alternative reconstruction formula for the continuous wavelet transform, which is applicable even if the admissibility condition is violated. The case of the transform with the standard reduced Morlet wavelet, which is an important example of such analysing functions, is discussed.
View Article and Find Full Text PDFExperimental data on spatial distributions of a pellet cloud electron density are necessary for the development of many applications of pellet injection, namely, plasma fuelling, discharge control, and plasma diagnostics. An improved approach of electron density measurements inside the cloud of a polystyrene pellet ablating in hot plasma of the large helical device is described. Density values of (1-30) × 10(16) cm(-3) depending on the background plasma parameters and distance from the solid pellet were measured.
View Article and Find Full Text PDFJ Inorg Biochem
August 2015
Institute of Chemistry, Saint Petersburg State University, Universitetskii Pr. 26, Saint Petersburg 198504, Russia. Electronic address:
Phys Chem Chem Phys
March 2015
Department of Physical Chemistry and Technology of Microsystem Devices, Saint Petersburg State Polytechnical University, Polytechnicheskaya st. 29, Saint Petersburg, 195251, Russia.
This paper covers the results from a study of the formation mechanism of fractal clusters from nanoparticles synthesised in atmospheric pressure radio frequency discharge. Two-dimensional structures with random configuration and self-similarity properties are formed by nanoparticles on a solid substrate surface. The typical linear dimensions of such structures are in the micron range.
View Article and Find Full Text PDFChem Biol
February 2015
Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. Electronic address:
Natural products are the most historically significant source of compounds for drug development. However, unacceptably high rates of compound rediscovery associated with large-scale screening of common microbial producers have resulted in the abandonment of many natural product drug discovery efforts, despite the increasing prevalence of clinically problematic antibiotic resistance. Screening of underexplored taxa represents one strategy to avoid rediscovery.
View Article and Find Full Text PDFAdv Gerontol
February 2018
Saint Petersburg Institute of Bioregulation and Gerontology, Saint-Petersburg, 197110, Rissian Federation;
The review describes neuro-immuno-endocrine signal molecules expression in human endometrial cells in the normal conditions, in the pathology and during aging. Human endometrial cells synthesizes estrogen, progesterone, estradiol, progestin, cell adhesion molecules (integrines α1β1, α4β1, αVβ3, L-selectin, Е-catgerin, MUC1), grow factors (TGF, EGF, HB-EGF, IGF), cytokines (IL-1, IL-2, INF-α, IL-12, СХСL10, CXCL11, CXCR3), various immune cells markers (CD68, CD105, CD163, CD16, CD56, CD4, CD8), heat shock proteins (HSP60, HSP70, HSP90, VEGF, MMP). Changes of this molecules expression level are the base of the social significant diseases as endometriosis, endometrial cancer and infertility.
View Article and Find Full Text PDFAdv Gerontol
February 2018
Institute of Human Brain, RAS, Saint-Petersburg, 197376, Russian Federation;
The review is dedicated to analysis of data available at present time concerning possible influence of stress upon telomere lengths and telomerase activity, as well as various ways of counteracting it. Present-day telomerase theory of aging gains a new impetus, shedding light upon the influence of psychological state of humans and their ability to counteract stress, upon the process of aging. It also tends to regard telomere shortening and the decrease in the activity of telomerase as a marker of level of the ability to adapt to both inner and outer influences.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
November 2014
Department of Mathematics and Statistics, University of Massachusetts, Amherst, Massachusetts 01003, USA.
The scattering of kinks and low-frequency breathers of the nonlinear sine-Gordon (SG) equation on a spatially localized parity-time-symmetric perturbation (defect) with a balanced gain and loss is investigated numerically. It is demonstrated that if a kink passes the defect, it always restores its initial momentum and energy, and the only effect of the interaction with the defect is a phase shift of the kink. A kink approaching the defect from the gain side always passes, while in the opposite case it must have sufficiently large initial momentum to pass through the defect instead of being trapped in the loss region.
View Article and Find Full Text PDFMol Cell
November 2014
Lomonosov Moscow State University, Department of Chemistry and A.N. Belozersky Institute of Physico-Chemical Biology, 119992 Moscow, Russia. Electronic address:
We demonstrate that the antibiotic amicoumacin A (AMI) is a potent inhibitor of protein synthesis. Resistance mutations in helix 24 of the 16S rRNA mapped the AMI binding site to the small ribosomal subunit. The crystal structure of bacterial ribosome in complex with AMI solved at 2.
View Article and Find Full Text PDFJ Proteomics
October 2014
Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Centre of the Russian Academy of Sciences, Kazan, Russia; Kazan (Volga Region) Federal University, Kazan, Russia.
Mycoplasmas (class Mollicutes), the smallest prokaryotes capable of self-replication, as well as Archaea, Gram-positive and Gram-negative bacteria constitutively produce extracellular vesicles (EVs). However, little is known regarding the content and functions of mycoplasma vesicles. Here, we present for the first time a proteomics-based characterisation of extracellular membrane vesicles from Acholeplasma laidlawii PG8.
View Article and Find Full Text PDFPhys Rev Lett
July 2014
Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany.
We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts.
View Article and Find Full Text PDFNeuron
April 2014
Department of Physiology, UT Southwestern Medical Center at Dallas, Dallas, TX 75390, USA; Laboratory of Molecular Neurodegeneration, Saint Petersburg State Polytechnical University, Saint Petersburg, 195251, Russia. Electronic address:
Mushroom dendritic spine structures are essential for memory storage, and the loss of mushroom spines may explain memory defects in Alzheimer's disease (AD). Here we show a significant reduction in the fraction of mushroom spines in hippocampal neurons from the presenilin-1 M146V knockin (KI) mouse model of familial AD (FAD). The stabilization of mushroom spines depends on STIM2-mediated neuronal store-operated calcium influx (nSOC) and continuous activity of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII).
View Article and Find Full Text PDFStructure
April 2014
Division of Biosciences, Institute for Structural and Molecular Biology, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK.
Eukaryotic TIP49a (Pontin) and TIP49b (Reptin) AAA+ ATPases play essential roles in key cellular processes. How their weak ATPase activity contributes to their important functions remains largely unknown and difficult to analyze because of the divergent properties of TIP49a and TIP49b proteins and of their homo- and hetero-oligomeric assemblies. To circumvent these complexities, we have analyzed the single ancient TIP49 ortholog found in the archaeon Methanopyrus kandleri (mkTIP49).
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