145 results match your criteria: "Saint Petersburg Electrotechnical University "LETI[Affiliation]"
Int J Mol Sci
January 2022
Institute of Experimental Medicine, Almazov National Medical Research Centre, 2 Akkuratova Str., 197341 Saint Petersburg, Russia.
In this paper, we describe the synthesis of multilayer nanoparticles as a platform for the diagnosis and treatment of ischemic injuries. The platform is based on magnetite (MNP) and silica (SNP) nanoparticles, while quinacrine is used as an anti-ischemic agent. The synthesis includes the surface modification of nanoparticles with (3-glycidyloxypropyl)trimethoxysilane (GPMS), the immobilization of quinacrine, and the formation of a chitosan coating, which is used to fix the fluorophore indocyanine green (ICG) and colloidal quantum dots AgInS/ZnS (CQDs), which serve as secondary radiation sources.
View Article and Find Full Text PDFPlants (Basel)
January 2022
Laboratory of Molecular and Ecological Physiology, Komarov Botanical Institute, Russian Academy of Sciences, ul. Professora Popova 2, 197376 St. Petersburg, Russia.
The microalga (formerly ) is able to accumulate high amounts of the carotenoid astaxanthin in the course of adaptation to stresses like salinity. Technologies aimed at production of natural astaxanthin for commercial purposes often involve salinity stress; however, after a switch to stressful conditions, experiences massive cell death which negatively influences astaxanthin yield. This study addressed the possibility to improve cell survival in subjected to salinity via manipulation of the levels of autophagy using AZD8055, a known inhibitor of TOR kinase previously shown to accelerate autophagy in several microalgae.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2021
Youth Research Institute, Saint Petersburg Electrotechnical University "LETI", 197376 Saint Petersburg, Russia.
This paper proposes a novel identification method for memristive devices using Knowm memristors as an example. The suggested identification method is presented as a generalized process for a wide range of memristive elements. An experimental setup was created to obtain a set of intrinsic I-V curves for Knowm memristors.
View Article and Find Full Text PDFFront Med (Lausanne)
December 2021
Clinic Management Department, First Pavlov State Medical University, St. Petersburg, Russia.
The aim of this research is to develop an accurate and interpretable aggregated score not only for hospitalization outcome prediction (death/discharge) but also for the daily assessment of the COVID-19 patient's condition. In this single-center cohort study, real-world data collected within the first two waves of the COVID-19 pandemic was used (27.04.
View Article and Find Full Text PDFSensors (Basel)
November 2021
Department of Robotics and Industrial Systems Automation, Saint Petersburg Electrotechnical University "LETI", Professora Popova 5, 197376 Saint Petersburg, Russia.
This paper presents a methodology for creating a soft sensor for predicting the bearing wear of electrical machines. The technique is based on a combination of Park vector methods and a classifier based on an artificial neural network (ANN-classifier). Experiments are carried out in laboratory conditions on an asynchronous motor of AIR132M4 brand.
View Article and Find Full Text PDFPolymers (Basel)
November 2021
Department of Micro- and Nanoelectronics, Faculty of Electronics, Saint Petersburg Electrotechnical University "LETI", 197376 Saint Petersburg, Russia.
Flexible polymer-based actuators, often also called artificial muscles, are an essential part of biomimetic systems that mimic the movement principles of animal world creatures. The most used electrode material to force the actuator move is an ensemble of noble metal nanoparticles in the electroactive polymer surface. Noble metal electrodes have enough electrical conductivity and elasticity and are not subjected to oxidation.
View Article and Find Full Text PDFAnn Anat
February 2022
North-Western State Medical University Named After I.I. Mechnikov, Department of Morphology, St. Petersburg, Russia.
Background: Traditionally, dynamic and functional anatomy, in particular the dynamic anatomy of the neck, is studied on cadaveric material. However, the development of in vivo visualization technologies and in silico modeling has made it possible to expand these possibilities. Despite significant progress in the study of dynamic and functional anatomy of the neck by means of in silico methods, the issues of validating the developed models and taking into account the pronounced nonlinearity of soft tissues as well as local anisotropy remain open.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
November 2021
Laboratory of Genomic Diversity, Center for Computer Technologies, Saint Petersburg National Research University of Information Technologies, Mechanics and Optics (ITMO University), 197101 St. Petersburg, Russia;
Animals (Basel)
September 2021
Department of Automation and Control Processes, Saint Petersburg Electrotechnical University "LETI", 197376 Saint Petersburg, Russia.
Canine ADHD-like behavior is a behavioral problem that often compromises dogs' well-being, as well as the quality of life of their owners; early diagnosis and clinical intervention are often critical for successful treatment, which usually involves medication and/or behavioral modification. Diagnosis mainly relies on owner reports and some assessment scales, which are subject to subjectivity. This study is the first to propose an objective method for automated assessment of ADHD-like behavior based on video taken in a consultation room.
View Article and Find Full Text PDFMetabolites
October 2021
Center for Algorithmic Biotechnology, Saint Petersburg State University, Saint Petersburg 199004, Russia.
Microbial natural products are a major source of bioactive compounds for drug discovery. Among these molecules, nonribosomal peptides (NRPs) represent a diverse class of natural products that include antibiotics, immunosuppressants, and anticancer agents. Recent breakthroughs in natural product discovery have revealed the chemical structure of several thousand NRPs.
View Article and Find Full Text PDFSci Rep
October 2021
Department of Computer Science and Engineering, Jadavpur University, Kolkata, India.
The analysis of human facial expressions from the thermal images captured by the Infrared Thermal Imaging (IRTI) cameras has recently gained importance compared to images captured by the standard cameras using light having a wavelength in the visible spectrum. It is because infrared cameras work well in low-light conditions and also infrared spectrum captures thermal distribution that is very useful for building systems like Robot interaction systems, quantifying the cognitive responses from facial expressions, disease control, etc. In this paper, a deep learning model called IRFacExNet (InfraRed Facial Expression Network) has been proposed for facial expression recognition (FER) from infrared images.
View Article and Find Full Text PDFInt J Mol Sci
September 2021
Department of Descriptive Geometry and Graphics, Faculty of Basic and Human Sciences, Saint-Petersburg Mining University, 2, 21st Line, 199106 Saint-Petersburg, Russia.
It was developed a new technique to assess micro- and mesopores with sizes below a few nanometers. The porous materials with hierarchical fractal-percolation structure were obtained with the sol-gel method. The tetraethoxysilane hydrolysis and polycondensation reactions were performed in the presence of salts as the sources of metal oxides.
View Article and Find Full Text PDFChaos
September 2021
Graduate Program in Electrical Engineering, Department of Electronic Engineering, Federal University of Minas Gerais, Belo Horizonte, MG 31270-901, Brazil.
Chaos-based image encryption schemes have been extensively employed over the past few years. Many issues such as the dynamical degradation of digital chaotic systems and information security have been explored, and plenty of successful solutions have also been proposed. However, the impact of finite precision in different hardware and software setups has received little attention.
View Article and Find Full Text PDFMicroorganisms
August 2021
Center of Translational Cancer Research (TranslaTUM), Klinikum Rechts der Isar, Technical University Munich, 81675 Munich, Germany.
In this study, the magnetic properties of magnetosomes isolated from lyophilized magnetotactic bacteria SO-1 were assessed for the first time. The shape and size of magnetosomes and cell fragments were studied by electron microscopy and dynamic light scattering techniques. Phase and elemental composition were analyzed by X-ray and electron diffraction and Raman spectroscopy.
View Article and Find Full Text PDFInt J Nanomedicine
November 2021
Institute of Cytology RAS, Saint-Petersburg, 194064, Russian Federation.
Background: A promising approach to solve the problem of cytostatic toxicity is targeted drug transport using magnetic nanoparticles (MNPs).
Purpose: To use calculation to determine the optimal characteristics of the magnetic field for controlling MNPs in the body, and to evaluate the efficiency of magnetically controlled delivery of MNPs in vitro and in vivo to a tumour site in mice.
Material And Methods: For the in vitro study, reference MNPs were used, while for in vivo studies, MNPs coated in polylactide including fluorescent indocyanine (MNPs-ICG) were used.
Am J Otolaryngol
January 2022
Department of Automation and Control Processes, Saint Petersburg Electrotechnical University "LETI", Saint Petersburg, Russian Federation. Electronic address:
In recent decades, semiconductor lasers have been successfully used in rhinology. However, their usage in the reduction of the nasal swell body (NSB) is barely studied. Our research aimed to conduct an experimental selection of the laser exposure mode in the NSB zone using a 970 nm diode laser for safe and effective NSB reduction.
View Article and Find Full Text PDFSci Rep
July 2021
Department of Computer Science and Engineering, Jadavpur University, Kolkata, 700032, India.
Cervical cancer affects more than 0.5 million women annually causing more than 0.3 million deaths.
View Article and Find Full Text PDFNanomaterials (Basel)
June 2021
Almazov National Research Centre, 197341 Saint-Petersburg, Russia.
In this study, we aimed to develop a technique for colloidal silver nanoparticle (AgNP) modification in order to increase their stability in aqueous suspensions. For this purpose, 40-nm spherical AgNPs were modified by the addition of either human albumin or Tween-80 (Polysorbate-80). After detailed characterization of their physicochemical properties, the hemolytic activity of the nonmodified and modified AgNPs was investigated, as well as their cytotoxicity and antimicrobial effects.
View Article and Find Full Text PDFSensors (Basel)
June 2021
Department of Biomedical Engineering, Saint Petersburg Electrotechnical University "LETI", 5 Prof. Popov Str., 197376 Saint Petersburg, Russia.
This paper describes the experimental results of testing a prototype of a high precision human skin rapid temperature fluctuations measuring instrument. Based on the author's work, an original circuit solution on a miniature semiconductor diode sensor has been designed. The proposed circuitry provides operation in the full voltage range with automatic setting and holding the operating point, as well as the necessary slope of the conversion coefficient (up to 2300 mV/°C), which makes it possible to register fast temperature oscillations from the surface of the human body and other biological objects.
View Article and Find Full Text PDFMicromachines (Basel)
June 2021
Department of Automation and Control Processes, Saint Petersburg Electrotechnical University "LETI", 197376 Saint Petersburg, Russia.
The problems of chronic or noncommunicable diseases (NCD) that now kill around 40 million people each year require multiparametric combinatorial diagnostics for the selection of effective treatment tactics. This could be implemented using the biosensor principle based on peptide aptamers for spatial recognition of corresponding protein markers of diseases in biological fluids. In this paper, a low-cost label-free principle of biomarker detection using a biosensor system based on fluorometric registration of the target proteins bound to peptide aptamers was investigated.
View Article and Find Full Text PDFBiomolecules
May 2021
Institute of Macromolecular Compounds of the Russian Academy of Sciences, Bolshoi pr. VO 31, 199004 St. Petersburg, Russia.
This study investigates the thermal and structural properties of multilayer composites based on chitosan (CS) and polyanions with different functionalities, including sodium sulfoethyl cellulose (SEC), sodium alginate (ALG), and sodium hyaluronate (HA). Unlike polyelectrolyte complexes (PECs) obtained by polymer mixing, the formation of a PEC layer by a process of layer-by-layer deposition of oppositely charged polymers is accompanied by the transformation of the CS polymorphic state, and this affects the relaxation and thermal properties of the resulting multilayer composite. X-ray diffraction analysis showed that the formation of the PEC layer in the CS/SEC multilayer film is accompanied by crystallization of the CS chains and the formation of a predominantly anhydrous CS modification.
View Article and Find Full Text PDFMaterials (Basel)
May 2021
Department of Micro- and Nanoelectronics, Faculty of Electronics, Saint Petersburg Electrotechnical University «LETI», 197376 Saint Petersburg, Russia.
The spectra of dielectric relaxation of macroporous silicon with a mesoporous skin layer in the frequency range 1-10 Hz during cooling (up to 293-173 K) and heating (293-333 K) are presented. Macroporous silicon (pore diameter ≈ 2.2-2.
View Article and Find Full Text PDFNanotechnology
May 2021
Alferov University, Saint-Petersburg 194021, Russia.
InGaN nanostructures are among the most promising candidates for visible solid-state lighting and renewable energy sources. To date, there is still a lack of information about the influence of the growth conditions on the physical properties of these nanostructures. Here, we extend the study of InGaN nanowires growth directly on Si substrates by plasma-assisted molecular beam epitaxy.
View Article and Find Full Text PDFInt J Mol Sci
April 2021
Laboratory of Molecular and Ecological Physiology, Komarov Botanical Institute, Russian Academy of Sciences, ul. Professora Popova 2, 197376 Saint Petersburg, Russia.
Mounting evidence from genomic and transcriptomic studies suggests that most genetic networks regulating the morphogenesis of land plant sporophytes were co-opted and modified from those already present in streptophyte algae and gametophytes of bryophytes . However, thus far, no candidate genes have been identified that could be responsible for "planation", a conversion from a three-dimensional to a two-dimensional growth pattern. According to the telome theory, "planation" was required for the genesis of the leaf blade in the course of leaf evolution.
View Article and Find Full Text PDFSensors (Basel)
April 2021
Department of Engineering, University of Applied Sciences Brandenburg, 14770 Brandenburg an der Havel, Germany.
Diagnostic devices for point-of-care (POC) urine analysis (urinalysis) based on microfluidic technology have been actively developing for several decades as an alternative to laboratory based biochemical assays. Urine proteins (albumin, immunoglobulins, uromodulin, haemoglobin etc.) are important biomarkers of various pathological conditions and should be selectively detected by urinalysis sensors.
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