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Intestinal microbiota correction in the therapy of irritable bowel syndrome (IBS) is an important medical problem. We conducted a laboratory and pilot clinical trial to investigate the effect of autoprobiotic bacteria, indigenous bifidobacteria and enterococci isolated from faeces and grown on artificial media to use as personified food additives in IBS treatment. Convincing evidence of the clinical efficacy of autoprobiotic was demonstrated by the disappearance of dyspeptic symptoms. The microbiome of patients with IBS was compared to a group of healthy volunteers and changes in the microbiome after autoprobiotic use were detected by quantitative polymerase chain reaction and 16S rRNA metagenome analysis. The possibility of reducing opportunistic microorganisms in the treatment of IBS with autoprobiotics has been convincingly proven. The quantitative content of enterococci in the intestinal microbiota was higher in IBS patients than in healthy volunteers and increased after therapy. An increase in the relative abundance of genera Coprococcus, Blautia and a decrease in the relative abundance of Paraprevotella spp. were found at the end of therapy. A metabolome study which was performed by gas chromatography and mass spectrometry demonstrated an increase in the content of oxalic acid, a decrease of dodecanoate, lauric acid, and other metabolome components after taking autoprobiotics. Some of these parameters correlated with the relative abundances of Paraprevotella spp., Enterococcus spp., and Coprococcus spp. representative of the microbiome. Apparently, they reflected the peculiarities of metabolic compensation and changes in the microbiota. Therefore, the use of autoprobiotics for treatment of IBS may lead to a stable positive clinical effect, associated with compensatory changes in the intestinal microbiota, and accompanied by corresponding changes in metabolic processes in the organism.

The article analyzes the current state of the fashion industry market during the coronavirus pandemic. Changes in the preferences of citizens and their impact on the production of fashionable good and selling them were identified. Methods of mathematical analysis, in particular the Gaussian normal distribution method, are able to overcome the difficulties of conducting full-scale sociological research during a pandemic and increase its effectiveness. © 2021 Ivanovo State Polytechnic University. All rights reserved.

The article presents the experience of the Institute of Pedagogy and Psychology of Petrozavodsk State University in creating the regional system of the continuous pedagogical education in the Republic of Karelia in conditions of the current socio-economic challenges to education, and the need to perform the tasks of the National project “Education”.The article reveals the problems of functioning and development of the system of professional pedagogical education, also describes the efficient mechanisms and directions of development. The key program activities and organizational conditions for improving the quality of the continuous pedagogical education in the Republic of Karelia have been identified.

Electrochemical sensors that can determine single/multiple analytes remain a key challenge in miniaturized analytical systems and devices. In this study, we present in situ synthesis and modification of gold nanodendrite electrodes to create an electrochemical system for the analysis of hydrogen peroxide. The sensor system consisted of the reference and counter electrodes as well as the working electrode. Electrochemical reduction of graphene oxide, ErGO, on the thin-film gold and gold nanodendrite working electrodes was used to achieve an efficient sensor interface for the adsorption of a biomimetic electrocatalytic sensor material, Mn(III) meso-tetra(N-methyl-4-pyridyl) porphyrin complex, with as high as 10–10 mol cm−2 surface coverage. The sensor system demonstrated a detection limit of 0.3 µM H2O2 in the presence of oxygen. Electrochemical determination of hydrogen peroxide in plant material in the concentration range from 0.09 to 0.4 µmol (gFW)−1 using the electrochemical sensor system was shown as well as in vivo real-time monitoring of the hydrogen peroxide dynamics as a sign of abiotic stress (intense sunlight). Results of the electrochemical determination were in good agreement with the results of biochemical analysis with the spectrophotometric detection. We anticipate that this method can be extended for the synthesis and integration of multisensor arrays in analytical microsystems and devices for the quantification and real-time in vivo monitoring of other analytes and biomarkers.

Comparative analysis of equilibrium structures of cations [RM(OCH2CH2)2NCH3]+ (M = Si, Ge; R = F, Me, Ph) and the corresponding neutral compounds HRM(OCH2CH2)2NCH3 was performed based on quantum-chemical calculations. The possibility was analyzed for expanding nuclear-chemical method to generation of cations having the atrane structure. Quantum-chemical method was applied to estimate the heights of barriers to hydrolysis by the М–О bond in ocanes acting as the sources of the corresponding cations with the atrane structure.

We report a new type of solid-state electrode (type I) of a simple design with polyvinyl chloride membranes based on Mn(III) tetraphenylporphyrin and with graphite as the electronically conducting substrate. Enlargement of the membrane/graphite contact area by soaking graphite in the plasticizer with subsequent conditioning of the electrode at 30 °C allowed us to shorten the time required to achieve steady potential values of the sensors to just 3 days. These electrodes do not require a specially added RedOx system in the transducer layer. Stabilization of the EMF response of type I electrodes is compared to type II electrodes which contain a Cu0/Cu2+ RedOx couple in the transducer layer. Type I sensors are suitable for measuring the salicylate ion concentration in the clinically important concentration range down to 2.5 × 10−4 M with a sensitivity to salicylate ion of −59.0 mV decade−1 in solutions with a high constant background of chloride ions of 0.12 M at pH = 5.3, making this a promising technique for an effective design of solid-contact ion-selective electrodes with polymeric sensing membranes.

Porphyrin macrocycles and their supramolecular nanoassemblies are being widely explored in energy harvesting, sensor development, catalysis, and medicine because of a good tunability of their light-induced charge separation and electron/energy transfer properties. In the present work, we prepared and studied photoresponsive porphyrin nanotubes formed by the self-assembly of meso-tetrakis(4-sulfonatophenyl)porphyrin and Sn(IV) meso-tetra(4-pyridyl)porphyrin. Scanning electron microscopy and transmission electron microscopy showed that these tubular nanostructures were hollow with open ends and their length was 0.4–0.8 μm, the inner diameter was 7–15 nm, and the outer diameter was 30–70 nm. Porphyrin tectons, H4TPPS42- : Sn(IV)TPyP4+, self-assemble into the nanotubes in a ratio of 2:1, respectively, as determined by the elemental analysis. The photoconductivity of the porphyrin nanotubes was determined to be as high as 3.1 × 10−4 S m−1, and the dependence of the photoconductance on distance and temperature was investigated. Excitation of the Q-band region with a Q-band of SnTPyP4+ (550–552 nm) and the band at 714 nm, which is associated with J-aggregation, was responsible for about 34 % of the photoconductive activity of the H4TPPS42--Sn(IV)TPyP4+ porphyrin nanotubes. The sensor properties of the H4TPPS42-- Sn(IV)TPyP4+ nanotubes in the presence of iodine vapor and salicylate anions down to millimolar range were examined in a chemiresistor sensing mode. We have shown that the porphyrin nanotubes advantageously combine the characteristics of a sensor and a transducer, thus demonstrating their great potential as efficient functional layers for sensing devices and biomimetic nanoarchitectures.

A series of chalcogenide glasses of various compositions, based on the TlI–Ag2S–As2S3 system, were prepared. The conductivity parameters and diffusion coefficients of silver and thallium radiotracers in the glass samples were determined. Chemical sensors with membranes of four glass compositions were prepared, and their analytical characteristics (sensitivity, selectivity, detection limit) were studied. Correlation between the ionic conductivity parameters of the ion-sensitive membranes and the analytical characteristics of chemical sensors for thallium ions in solutions was found.

Bioinspired molecular complexes that mimic the enzymatic catalysis of redox transformations offer a versatile platform for the development of non-enzymatic mediatorless sensors with high sensitivity, selectivity, and robustness without the use of precious metals. The aim of this study was to prepare and investigate biomimetic sensors based on the electrocatalytic reduction of hydrogen peroxide and oxygen by a series of immobilized complexes of iron and manganese with porphyrin macrocycles for the detection of hydrogen peroxide and glucose. The influence of substitution of the macroheterocyclic ligand, composition of the adsorption solution, Nafion membrane, and amino acids on the properties of the sensors was studied. Optimized sensor function is based on the electrogenerated reduced form of Mn(II) meso-tetra(N-methyl-4-pyridyl) porphyrin as a catalyst and allows high sensitivity of the hydrogen peroxide detection of 1.8 A M−1 cm−2 and 0.071 A M−1 cm−2 to be achieved in the lower and higher concentration ranges, respectively, with a low detection limit of 5⋅10−7 M at physiological pH 7.4 and in the presence of oxygen. The MnTMPyP electrode was investigated as an electrochemical transducer in the glucose-oxidase-based biosensor. The sensors were successfully applied for the detection of hydrogen peroxide and glucose in human serum samples. Along with a simple fabrication procedure and robustness of the sensor, the biomimetic electrocatalytic properties of the MnTMPyP complex facilitate excellent performance of the proposed sensors for hydrogen peroxide and glucose determination in biological media, emphasizing the importance of bioinspired electrocatalytic metalloporphyrin complexes for the development of sensors and point-of-care devices.

The tunable characteristics of the porphyrin molecular tectons have given rise to interest in investigating the self-assembled porphyrin nanoarchitectures for designing new materials. Nanostructures created by the self-assembly of meso-tetrakis(4-sulfonatophenyl)porphine and Co(III) meso-tetra(4-pyridyl)porphine chloride and their photoconductivity are reported here. These nanostructures were characterized by electron microscopy. The ratio of porphyrin tectons in the binary porphyrin nanostructures is about 3:2. The nanostructures demonstrate a high photoconductivity of about 5 × 10−5 S m−1. The dependence of the photoconductivity of the porphyrin nanostructures on the path length and temperature is demonstrated.

New membrane materials were studied for thallium (I)-selective chemical sensors based on chalcogenide glasses in the TlI-Ag 2 S-As 2 S 3 system. Using these studies on the radioactive tracers diffusion ( 108m Ag и 204 Tl) and electrical conductivity, an ionic conductivity of σ ion = 10 −7 Ohm −1 cm −1 (20 °C) was found for the glass composition 27%TlI-20%Ag 2 S-53%As 2 S 3 . This composition of chalcogenide glass was selected as a membrane material for the Tl-selective chemical sensor displaying a value of the electrode function of 57 mV/pTl and a detection limit of 3 × 10 −6 mol l −1 .

Two types of gold nanostructures are discussed: charge(citrate)-stabilized and sterically(OA)-stabilized gold nanostructures and their assembly with heme-containing metalloproteins, cyt c and horseradish peroxidase (HRP) enzyme into a bioelectrochemically active nanoarchitecture as well as a sensor application. The assembly of the nanostructures on the thin-film gold electrodes and the immobilization and electrochemical properties of metalloproteins on these electrodes are presented. The nanostructured bioelectrochemical interfaces provide a good environment for the stable and reproducible immobilization of electroactive proteins. We show that both molecules preserve their functionalities (electrochemical and biocatalytic activities). The amount of electroactive proteins immobilized on the nanostructured electrode surfaces is significantly increased compared to the flat electrode surfaces. The kinetic parameters of the heterogeneous direct electron transfer reaction of cyt c on the nanostructured electrodes are compared. The thin-film gold electrodes modified with OANWs, OANPs, and citrate-stabilized NPs and covalently immobilized HRP exhibit an excellent catalytic activity toward the oxidation of hydrogen peroxide with a working concentration range from 20 μM to 500 μM, a sensitivity of 0.031 A M−1 cm−2 (RSD 0.005), 0.027 A M−1 cm−2 (RSD 0.004), and 0.022 A M−1 cm−2 (RSD 0.0035), and a detection limit of 5 μM, 8 μM, and 14 μM, respectively (RSDs near the detection limits were 9–12%). The HRP sensor characteristics are improved significantly compared to the flat thin-film sensors by using gold nanostructures. Our study shows that ultrathin gold nanowires and nanoparticles with two different types of stabilizing agents are promising materials for assembling biomolecules into functional nanoarchitectures for metalloprotein-based bioelectrochemical sensors.

Modern research techniques with radioactive isotopes were used to study the transport characteristics, (conductivity and diffusion) in chalcogenide membrane materials of the Ag2S-As2S3-TlI system. It was demonstrated that, on raising the silver sulfide concentration in a glass, the total electrical conductivity grows by two orders of magnitude, which is due to the pronounced change of the band structure and to the increase in the electronic component of the conductivity. New chemical sensors for determination Tl ions in solutions were developed on the basis of these solid-state studies.

Conductivity and 204Tl tracer diffusion measurements have been carried out in the (Tl2S)x(GeS)60(GeS2)40 − x glassy system, where the Tl2S concentration changes between 0 ≤ x ≤ 25. The room temperature dc conductivity increases by 7 orders of magnitude with increasing thallium concentration, ranging between 10− 18 S cm− 1 for the 60GeS-40GeS2 matrix and 10− 11 S cm− 1 for Tl2S-rich glasses. The activation energy decreases from 1.22 to 0.79 eV, respectively. The conductivity and thallium diffusion results reveal that the ionic transport becomes to be predominant at high thallium concentrations (≈ 15 at.% Tl). The thallium ion transport number t Tl + increases from 10− 3 for low cation concentrations to t Tl + ≅ 1 for the x = 20 sample. The Haven ratio, HR ≈ 1, indicates uncorrelated ion motion even at rather high thallium concentrations. The obtained results are discussed in comparison with similar (Ag2S)x(GeS)60(GeS2)40 − x glassy system.

Tl4HgI6 solid electrolyte with a high ionic component of conductivity was synthesized for developing a thallium-sensitive sensor. The main sensor characteristics (tilt angle, detection limit, selectivity, pH range, potential drift) of the new thallium sensor were determined. The time stability of its operation and various ways of its application for determining thallium ions in solutions are demonstrated.

High aspect ratio ultrathin (d

Radioisotope studies of the choleresis function of the liver, ultrasonic studies of the liver and contractile function of the gallbladder and gastroduodenoscopy were carried out in eight subjects after a 24-h stay in a 12° antiorthostatic position (AOP) simulating the hemodynamic changes in the abdominal cavity caused by microgravity. The dynamically hindered venous blood outflow from the liver induced in the AOP model caused activation of choleresis on an empty stomach. This activation manifested itself as an increase in the central perfusion zone of the liver parenchyma, dilation of the biliary ductules, and contraction of the gall-bladder, as well as choleresis into the duodenum. Activation of choleresis in the liver took place against the background of a reduction of the area of radioactive marker distribution in the liver and a decrease in the hepatocyte metabolic activity and the concentration function of the biliary excretion system. The functional characteristics of the liver in the AOP model reflected the reaction caused by changes in its blood content due to the changes in the body position negative to the gravity vector. The mechanism of the changes includes the occurrence of a dynamic venous plethora in the liver; centralization of hepatic blood flow, and activation of choleresis activity against the background of peripheral blood flow depletion, as well as the reduction of metabolic activity of hepatocytes and the concentration function of the biliary excretion system.

The review presents a short record of the evolution of chemical sensors (ion selective electrodes) and multisensor systems of an electronic tongue type, based on the organization principles similar to those of biological sensors. The main types of chemical sensors and multisensor electronic tongue combinations elaborated today are considered along with sensitive materials used in them. Recent advances in chemical sensors, for example, lower detection limits and so-called true selectivity are scrutinized. Also, some widespread analytical applications of electron tongues, including those for the identification and classification of liquid media, for the quantification of various components in there, for the control of industrial processes, as well as the type and intensity evaluation of the taste of food and medications are discussed.

Dye molecules were suggested as a sensitive element for an optical sensor of parameters determining the efficiency of a fuel cell with a proton-exchange membrane, in which a water-methanol mixture is used as a fuel. The sensitivity of representatives of three different types of dyes to the concentrations of protons and methanol was examined.

A novel effective bioelectrochemical sensor interface for enzyme biosensors is proposed. The method is based on in situ synthesis of gold nanostructures (5–15 nm) on the thin-film electrode surface using the oleylamine (OA) method, which provides a high-density, stable, electrode interface nanoarchitecture. New method to activate the surface of the OA-stabilized nanostructured electrochemical interface for further functionalization with biomolecules (glucose oxidase enzyme) using Meerwein's salt is proposed. Using this approach a new biosensor for glucose determination with improved analytical characteristics: wide working range of 0.06–18.5 mM with a sensitivity of 22.6 ± 0.5 μA mM− 1 cm− 2, limit of detection 0.02 mM, high reproducibility, and long lifetime (60 d, 93%) was developed. The surface morphology of the electrodes was characterized by scanning electron microscopy (SEM). The electrochemical properties of the interface were studied by cyclic voltammetry and electrochemical impedance spectroscopy using a Fe(II/III) redox couple. The studies revealed an increase in the electroactive surface area and a decrease in the charge transfer resistance following surface activation with Meerwein's reagent. A remarkably enhanced stability and reproducibility of the sensor was achieved using in situ synthesis of gold nanostructures on the electrode surface, while surface activation with Meerwein's salt proved indispensable in achieving an efficient bioelectrochemical interface.

In this work, ion-selective field-effect transistors (ISFET), light-addressable potentiometric sensors (LAPS) and miniaturised ion-selective electrodes (μISE) are investigated for the detection of cadmium ions in aqueous solutions for future multi-sensor applications. The sensor membranes are based on a chalcogenide glass material (CdSAgIAs 2 S 3 ) that has been deposited as thin film onto different transducer structures by means of the pulsed laser deposition (PLD) technique. The prepared thin films were physically characterised by means of optical microscopy, Rutherford backscattering spectrometry (RBS) and scanning electron microscopy (SEM). The electrochemical characterisation was done by means of ion-selective potentiometry (μISE), current/voltage, constant current (LAPS) and constant-charge mode (ISFET) measurements.

Summary Crystallographic analysis of biological and non-biological minerals does not reveal any significant differences between the two, which is indicative of common crystallization processes. It can be supposed that the human organism is a biocrystalloid in a sense that it is regarded both at the level of the whole organism and individual cells as a composite entity consisting of a crystal-like structure and pericrystalline medium. A similarity can be found between the growing layer of a crystal in the crystal-forming medium and a cell structure with liquid washing it. A mineral organism therefore can be regarded as the active superficial part of a crystal taken together with pericrystalline crystal-forming medium which controls crystal growth and modifies the system depending on the structure of the growing system. Aggregation is one of the fundamental features of minerals as they are found primarily not only as separate objects but also as aggregates, i.e. regular cohesive masses or synmineralogical systems. Ability to aggregation in an orderly way is expressed as self-organization. This feature is inherent not only to compound molecules but also to associates of a higher order. The cell biology has shown that when similar cells touch each other they tend to cohere forming aggregates characteristic of the given cell population. Similar live systems and their components that perform the same function have an ability to integrate and form firstly a conglomerate (colony) and then an organism. Integration explains association of multi-segmented entities into a single organism and the resulting structure would consists of the two groups of segments, i.e. appearance of an organism consisting of two different but of the same type specimens, each of which had different number of segments. Phylogenetically, an early precursor of the man evolved from a simple cell into an integrated multi-segment organism through several stages – initially a simple cell, then a cell colony, then a single-segment organism, then an organism like a concave ball, then a colony of one-segment multicellular organisms and finally a multi-segment multicellular organism. Integration of five- and eight-segment organisms resulted in the formation of a 13-segment precursor organism of man. Segmentation is nothing else but traces of boundaries left following integration of separate multicellular non-segmented specimens with gradual fading of their differences and formation of a new entity in compliance with formation laws.

The light-addressable potentiometric sensor (LAPS) is a semiconductor-based chemical sensor with an electrolyte–insulator–semiconductor structure. The LAPS can have many measuring points integrated on the sensing surface, which are individually accessed by a light beam. By modifying the measuring points with different materials, a single sensor plate can be used as a multi-analyte sensor. In this paper, instrumentation and application of LAPS to multi-ion sensing and imaging are described. As a new application of LAPS, potentiometric imaging of a microfluidic channel is proposed.

A multisensor with a four-sectional membrane based on two Li- and two K-ionophores with different selectivities has been developed based on the laser-scanned silicon transducer (LSST), where the responses of the sensor sections have been measured by scanning the potentials at different points on the membrane surface. An artificial neural network (ANN) was employed for the analysis of mixed solutions. It has been demonstrated that by applying this hybrid sensor as a laser-scanned multisensor system, the concentration regions for the simultaneous determination of lithium and potassium ions in complex solutions have been enlarged significantly. It has been shown that using such a kind of multisensor system makes it possible to overcome the restriction of the selectivity in comparison with single sensors.

Various methods for the immobilization of urease and butyrylcholinesterase on the insulator surface of a laser-scanned semiconductor transducer (LSST) have been tested and compared for the development of an enzyme-based light-addressable potentiometric sensor (LAPS). The method of preparing photocurable membranes on LAPS is presented, and a new type of enzyme LAPS with photocurable polymeric enzyme membranes has been elaborated. It was found that sensors prepared by means of covalent bonding and cross-linking with inactive protein (type SIII) and with photocurable membrane matrices (type SIV) are more prospective. The enzyme LAPSensors with photocurable membranes demonstrate a degree of sensitivity close to the theoretical value and working ranges of 6.3·10−5−1.1·10−2 and 1·10−4−1·10−1 mol L−1 urea for acrylamide and acrylate-based membrane matrices, respectively, and 2.5·10−4−2·10−1 mol L−1 butyrylcholine for an acrylamide membrane matrix. It is shown that such sensors can be also used for the analysis of enzyme inhibitors.

A novel design of the light-addressable potentiometric sensor (LAPS) for realisation of a portable multisensor device is presented. Light sources and electronics including an oscillator, a multiplexer, a pre-amplifier and a high-pass filter are encapsulated in a pen-shaped case, on which the sensor plate is mounted. This sensor device is capable of measuring up to four different ion species by integrating different ion-selective materials on the sensing surface, each illuminated with an independent light source. The novel design of the sensor system is expected to make the measurement easier and to enlarge the field of practical applications.

A K+-sensitive capacitive electrolyte-membrane-insulator-semiconductor (EMIS) sensor has been developed. The sensor utilizes a valinomycin-containing PVC-based membrane with different contents of plasticizer. This new type of sensor has been investigated in terms of its intrinsic characteristics, like impedance behavior, capacitance/voltage characteristics and frequency dependence. The optimized working conditions of the sensor and various membrane compositions have been studied with regard to the sensitivity performance in different electrolytes. The possibility of future applications for the measurement of extracellular potassium-ion concentrations are discussed.

In the present work a double ion sensor based on a laser scanned semiconductor transducer (LSST) for the simultaneous determination of K + - and Ca 2+ -ions in solutions has been developed. Specially elaborated ion-sensitive membrane compositions based on valinomycin and calcium ionophore calcium bis[4-(1,1,3,3-tetramethylbutyl)phenyl] phosphate (t-HDOPP-Ca) were deposited as separate layers on a silanized surface of the Si/SiO 2 /Si 3 N 4 -transducer. The proposed multi-sensor exhibits theoretical sensitivities and the detection limits of the sensor were found to be 2×10 −6 mol l −1 for K + and 5×10 −6 mol l −1 for Ca 2+ . The elaborated double sensor is proposed for the first time as a prototype of a new type of multi-sensor systems for chemical analysis.

A new type of light-addressable potentiometric sensor (LAPS) has been developed by elaboration of photocurable ion-sensitive membranes based on matrices of mono- and diacrylates in combination with a silicon-based electrochemical transducer for the purposes of chemical and biochemical analyses. The characteristics of the elaborated K-, Li-, Cs-, Ca- and Mg-LAPS are presented to indicate the potential of the technology developed. For example, the sensitivities of the K- and Li-LAPS were found to be 58±1 mV/pK and 59±1 mV/pLi, respectively, over concentration ranges of 10 −5 –10 −1 mol/l. The detection limits were evaluated to be 2×10 −6 mol/l of the primary ion.

A lithium-selective polymeric membrane has been immobilised on the surface of a semiconductor transducer. This light-addressable potentiometric sensor (LAPS) with the induced lithium selectivity has been prepared with the aim at further development of a Li+ assay in liquid media, including biological fluids. The sensor developed exhibits Nernstian response interval of 10−5 to 10−1 mol l−1 with an ionic sensitivity of (58±1) mV/pLi. The detection limit was found to be (3±1)×10−6 mol l−1 Li+. The sensor has high selectivity for lithium over sodium and potassium ions with selectivity coefficients of KLi/NaPOT=(7±2)×10−3 and KLi/KPOT=(5±1)×10−3, respectively, and a response time of less than 30 s.

Methods of silicon planar technology and pulsed laser deposition were applied to fabricate fully solid-state chemical sensors for determining ions of copper, lead, cadmium, thallium, and also sulfide and chloride ions on the basis of thin chalcogenide films as ion-sensitive membranes.

Brief historical summary about Institute' vibroacoustic factors investigations development in the XXth century is presented. There are shown the data of noise, vibration, ultra- and infrasound hygienic rating in comparison with international approaches; the ways of its international harmonization in modern social and economic situation are selected.