95 results match your criteria: "St. Petersburg Electrotechnical University[Affiliation]"
Nanomaterials (Basel)
December 2024
Personalized Medicine Centre, Almazov National Medical Research Centre, Akkuratova Str. 2, 197341 St. Petersburg, Russia.
This study addresses issues in developing spatially controlled magnetic fields for particle guidance, synthesizing biocompatible and chemically stable MNPs and enhancing their specificity to pathological cells through chemical modifications, developing personalized adjustments, and highlighting the potential of tumor-on-a-chip systems, which can simulate tissue environments and assess drug efficacy and dosage in a controlled setting. The research focused on two MNP types, uncoated magnetite nanoparticles (mMNPs) and carboxymethyl dextran coated superparamagnetic nanoparticles (CD-SPIONs), and evaluated their transport properties in microfluidic systems and porous media. The original uncoated mMNPs of bimodal size distribution and the narrow size distribution of the fractions (23 nm and 106 nm by radii) were demonstrated to agglomerate in magnetically driven microfluidic flow, forming a stable stationary web consisting of magnetic fibers within 30 min.
View Article and Find Full Text PDFSensors (Basel)
November 2024
Department of Microelectronics and Radio Engineering, St. Petersburg Electrotechnical University "LETI", 197022 St. Petersburg, Russia.
Power amplifiers are crucial components that significantly influence the linearity and energy efficiency of next-generation communication system radio units. A key challenge in designing power amplifiers is managing high peak-to-average power ratio (PAPR) in order to achieve both high linearity and energy efficiency during back-off conditions. This paper presents simulation and measurement results for a dynamic load modulation power amplifier based on a ferroelectric tunable matching network to operate at 2.
View Article and Find Full Text PDFFront Med (Lausanne)
November 2024
Personalized Medicine Centre, Almazov National Medical Research Centre, Saint Petersburg, Russia.
Acute and requiring attention problem of oncotheranostics is a necessity for the urgent development of operative and precise diagnostics methods, followed by efficient therapy, to significantly reduce disability and mortality of citizens. A perspective way to achieve efficient personalized treatment is to use methods for operative evaluation of the individual drug load, properties of specific tumors and the effectiveness of selected therapy, and other actual features of pathology. Among the vast diversity of tumor types-brain tumors are the most invasive and malignant in humans with poor survival after diagnosis.
View Article and Find Full Text PDFPolymers (Basel)
September 2024
Joint Stock Company Scientific and Production Corporation S.I. Vavilov State Optical Institute, Babushkina Str. dom 36, Korpus 1, St. Petersburg 192171, Russia.
A large number of the thin-film organic structures (polyimides, 2-cyclooctylarnino-5-nitropyridine, N-(4-nitrophenyl)-(L)-prolinol, 2-(n-Prolinol)-5-nitropyridine) sensitized with the different types of the nano-objects (fullerenes, carbon nanotubes, quantum dots, shungites, reduced graphene oxides) are presented, which are studied using the holographic technique under the Raman-Nath diffraction conditions. Pulsed laser irradiation testing of these materials predicts a dramatic increase of the laser-induced refractive index, which is in several orders of the magnitude greater compared to pure materials. The estimated nonlinear refraction coefficients and the cubic nonlinearities for the materials studied are close to or larger than those known for volumetric inorganic crystals.
View Article and Find Full Text PDFPhys Chem Chem Phys
September 2024
Department of Chemistry, Oakland University, 146 Library Drive, Rochester, Michigan 48309, USA.
The fascination with superheavy elements (SHE) spans the nuclear physics, astrophysics, and theoretical chemistry communities. Extreme relativistic effects govern these elements' chemistry and challenge the traditional notion of the periodic law. The experimental quest for SHE critically depends on theoretical predictions of these elements' properties, especially chemical homology, which allows for successful prototypical experiments with more readily available lighter homologues of SHE.
View Article and Find Full Text PDFMaterials (Basel)
July 2024
Department of Physical Electronics and Technology, St. Petersburg Electrotechnical University "LETI", Prof. Popov str., 5F, St. Petersburg 197022, Russia.
The purpose of this work is to study the kinetics of the heat flow heating the substrate, which is generated by a two-layer sandwich magnetron target when sputtered in argon. Its novelty resides in the application of the COMSOL Multiphysics to study the kinetics of thermal processes during sputtering of a target of the new type. The analysis was performed for a sandwich target with internal copper and external titanium plates when the discharge power varied in the range of 400-1200 W.
View Article and Find Full Text PDFSci Data
June 2024
Department of Computer Science and Engineering, St. Petersburg Electrotechnical University "LETI", 197022, Saint Petersburg, Russia.
Pulmonary hypertension (PH) is a syndrome complex that accompanies a number of diseases of different etiologies, associated with basic mechanisms of structural and functional changes of the pulmonary circulation vessels and revealed pressure increasing in the pulmonary artery. The structural changes in the pulmonary circulation vessels are the main limiting factor determining the prognosis of patients with PH. Thickening and irreversible deposition of collagen in the pulmonary artery branches walls leads to rapid disease progression and a therapy effectiveness decreasing.
View Article and Find Full Text PDFNanomaterials (Basel)
April 2024
Joint Stock Company Scientific and Production Corporation, S.I. Vavilov State Optical Institute, Babushkona Str. 36/1, 192171 St. Petersburg, Russia.
Among different inorganic and organic polarizer elements, thin-film light polarizers occupy a special place because of their flexibility, ease of integration into any optoelectronic circuit, and good functioning in the visible and near-infrared spectral range and can compete with Glan and Nicolas volumetric prisms. This paper presents the results of a study on how carbon-based nanoparticles influence on the basic properties of a well-known PVA-based polymer matrix, using which it is possible to obtain good transparency for parallel light components. An accent is made on graphene oxide nanoparticles, which are used as PVA sensitizers.
View Article and Find Full Text PDFPharmaceuticals (Basel)
January 2024
Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia.
Bull Exp Biol Med
January 2024
I. P. Pavlov First St. Petersburg State Medical University, Ministry of Health of the Russian Federation, St. Petersburg, Russia.
A morphological analysis of the liver of Wistar rats was performed 2 months after a single intravenous injection of porous silicon particles of different sizes (60-80, 250-300, and 500-600 nm; 2 mg/ml, 1 ml). Histological, immunohistochemical, and electron microscopic methods showed the development of CD68 granulomas in all experimental groups. Injection of 60-80-nm porous silicon particles led to the formation of single large granulomas (>2000 μm), while 500-600-nm nanoparticles caused the formation of numerous smaller granulomas.
View Article and Find Full Text PDFInt J Mol Sci
November 2023
Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 420008 Kazan, Russia.
In the last decade, Ficin, a proteolytic enzyme extracted from the latex sap of the wild fig tree, has been widely investigated as a promising tool for the treatment of microbial biofilms, wound healing, and oral care. Here we report the antibiofilm properties of the enzyme immobilized on soluble carboxymethyl chitosan (CMCh) and CMCh itself. Ficin was immobilized on CMCh with molecular weights of either 200, 350 or 600 kDa.
View Article and Find Full Text PDFHeliyon
November 2023
St. Petersburg Electrotechnical University "LETI", 5-F Professor Popov street, St. Petersburg, 197022, Russia.
In a changing climate, forest ecosystems have become increasingly vulnerable to continuously exacerbating heat and associated drought conditions. Climate stress resilience is governed by a complex interplay of global, regional, and local factors, with hydrological conditions being among the key players. We studied a Scots pine ( L.
View Article and Find Full Text PDFInt J Mol Sci
October 2023
Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia.
Small heat shock proteins (sHSPs) represent a first line of stress defense in many bacteria. The primary function of these molecular chaperones involves preventing irreversible protein denaturation and aggregation. In , fibrillar IbpA binds unfolded proteins and keeps them in a folding-competent state.
View Article and Find Full Text PDFJ Appl Stat
March 2023
Institute of Computer Science and Technologies, Peter the Great St.-Petersburg Polytechnic University, St.-Petersburg, Russia.
Change-point detection methods are proposed for the case of temporary failures, or transient changes, when an unexpected disorder is ultimately followed by a re-adjustment and return to the initial state. A base distribution of the 'in-control' state changes to an 'out-of-control' distribution for unknown periods of time. Likelihood based sequential and retrospective tools are proposed for the detection and estimation of each pair of change-points.
View Article and Find Full Text PDFNanomaterials (Basel)
August 2023
Computer-Aided Design Department, St. Petersburg Electrotechnical University "LETI", 5 Professora Popova St., 197022 Saint Petersburg, Russia.
AlF has interesting electrophysical properties, due to which the material is promising for applications in supercapacitors, UV coatings with low refractive index, excimer laser mirrors, and photolithography. The formation of AlF-based nano- and micro-wires can bring new functionalities to AlF material. AlF nanowires are used, for example, in functionally modified microprobes for a scanning probe microscope.
View Article and Find Full Text PDFPolymers (Basel)
June 2023
Vavilov State Optical Institute, Kadetskaya Liniya V.O. 5/2, 199053 St. Petersburg, Russia.
Due to the high demand for optoelectronics for use in new materials and processes, as well as the search for their modeling properties, the expansion of the functionality of modified materials using nanotechnology methods is relevant and timely. In the current paper, a specific nanotechnology approach is shown to increase the refractive and photoconductive parameters of the organic conjugated materials. The sensitization process, along with laser treatment, are presented in order to improve the basic physical-chemical properties of laser, solar energy, and general photonics materials.
View Article and Find Full Text PDFMicroorganisms
May 2023
Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia.
Probiotic bacteria exhibiting antagonistic activities against pathogenic bacteria are widely considered as potential options for the prevention and treatment of various infectious diseases and represent potential substitutes of antibiotics. Here we show that the AG10 strain represses the growth of and in vitro and diminishes their negative effects in vivo in a model of survival on embryonic (larvae) and pupa stages. In an agar drop diffusion test, AG10 exhibited antagonistic properties against , , and , and repressed the growth of and during milk fermentation.
View Article and Find Full Text PDFInt J Mol Sci
May 2023
Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia.
In the last decades, it has been shown that biofilm-associated infections in most cases are caused by rather two or even more pathogens than by single microorganisms. Due to intermicrobial interactions in mixed communities, bacteria change their gene expression profile, in turn leading to alterations in the biofilm structure and properties, as well as susceptibility to antimicrobials. Here, we report the alterations of antimicrobials efficiency in mixed biofilms of - in comparison with mono-species biofilms of each counterpart and discuss possible mechanisms of these alterations.
View Article and Find Full Text PDFMaterials (Basel)
April 2023
Department of Physical Electronics and Technology, St. Petersburg Electrotechnical University "LETI", Prof. Popov Str., 5F, 197022 St. Petersburg, Russia.
This work critically reviews the evolution of reactive sputtering modeling that has taken place over the last 50 years. The review summarizes the main features of the deposition of simple metal compound films (nitrides, oxides, oxynitrides, carbides, etc.) that were experimentally found by different researchers.
View Article and Find Full Text PDFSensors (Basel)
April 2023
Engineering Center of Microtechnology and Diagnostics, St. Petersburg Electrotechnical University (ETU «LETI»), Professora Popova str. 5, 197022 St. Petersburg, Russia.
The features of the wide band gap SiC semiconductor use in the capacitive MOSFE sensors' structure in terms of the hydrogen gas sensitivity effect, the response speed, and the measuring signals' optimal parameters are studied. Sensors in a high-temperature ceramic housing with the Me/TaO/SiC/4H-SiC structures and two types of gas-sensitive electrodes were made: Palladium and Platinum. The effectiveness of using Platinum as an alternative to Palladium in the MOSFE-Capacitor (MOSFEC) gas sensors' high-temperature design is evaluated.
View Article and Find Full Text PDFSci Data
March 2023
Institute for Fundamental Medicine and Biology, Kazan Federal University, Kazan, 420008, Russia.
Differential fluorescent staining is an effective tool widely adopted for the visualization, segmentation and quantification of cells and cellular substructures as a part of standard microscopic imaging protocols. Incompatibility of staining agents with viable cells represents major and often inevitable limitations to its applicability in live experiments, requiring extraction of samples at different stages of experiment increasing laboratory costs. Accordingly, development of computerized image analysis methodology capable of segmentation and quantification of cells and cellular substructures from plain monochromatic images obtained by light microscopy without help of any physical markup techniques is of considerable interest.
View Article and Find Full Text PDFFront Neuroinform
February 2023
Institute for Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia.
Introduction: Complex gait disturbances represent one of the prominent manifestations of various neurophysiological conditions, including widespread neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Therefore, instrumental measurement techniques and automatic computerized analysis appears essential for the differential diagnostics, as well as for the assessment of treatment effectiveness from experimental animal models to clinical settings.
Methods: Here we present a marker-free instrumental approach to the analysis of gait disturbances in animal models.
Biomed Eng (NY)
January 2023
Department of Biotechnical Systems, St. Petersburg Electrotechnical University (LETI), St. Petersburg, Russia.
Stages in the development of a system for remote monitoring of the state of health of people with chronic diseases are discussed, as are means of carrying out tasks at each stage, approaches to assessing ongoing state, and monitoring, controlling, and predicting exacerbations of chronic diseases.
View Article and Find Full Text PDFPathogens
December 2022
Laboratory of Molecular Genetics of Microorganisms, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia.
and are human pathogens that are able to form mixed biofilms on the surface of mucous membranes, implants and catheters. In biofilms, these pathogens have increased resistance to antimicrobials, leading to extreme difficulties in the treatment of mixed infections. The growing frequency of mixed infections caused by and requires either the development of new antimicrobials or the proposal of alternative approaches to increase the efficiency of conventional ones.
View Article and Find Full Text PDFPhys Rev Lett
December 2022
Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany.
One of the most enduring and intensively studied problems of x-ray astronomy is the disagreement of state-of-the art theory and observations for the intensity ratio of two Fe XVII transitions of crucial value for plasma diagnostics, dubbed 3C and 3D. We unravel this conundrum at the PETRA III synchrotron facility by increasing the resolving power 2.5 times and the signal-to-noise ratio thousandfold compared with our previous work.
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