Search

Therapeutic significance in the studies of HIFU-induced effects of is attached to the local heating of tissues, but the role of the mechanical component caused by non-stationary cavitation is practically not taken into account. Calculations show that the temperature inside cavitation bubbles can differ significantly from the temperature in the thermal ablation zone, and the developing temperature gradient can change the formation of the thermal field. Collapsing bubbles can cause mechanical destruction of tissues.

Results are presented from research to determine dependences of characteristics of dose distributions in biological objects on their thickness and density, and the energy of electron beams used in the radiation processing of food products.

Publications showing the prospects of combining computer simulation with atomic force microscopy in the study of polymer biological objects and materials for various purposes are analyzed. The problems that arise when these methods are used together are described. Three main directions are presented in which atomic force microscopy is used in conjunction with computer simulation: study of the surface topography of polymer materials; measurement of the force curve of the interaction of the atomic force probe with polymer structures; and determination of the energy of intermolecular interactions.

Using carbon nanotubes for sensing the mass in a biosensor is recently proven as an emerging technology in healthcare industry. This study investigates relative frequency shifts and sensitivity studies of various biological objects such as insulin hormone, immunoglobulin G (IgG), the most abundant type of antibody, and low-density lipoproteins (LDL) masses using the single-wall carbon nanotubes as a biomass sensor via continuum mechanics. Uniform distributed mass is applied to the single-wall carbon nanotube mass sensor. In this study, fixed-free and fixed-fixed type single-wall carbon nanotubes with various lengths of relative frequency shifts are studied. Additionally, the sensitivity analysis of fixed-free and fixed-fixed type CNT biological mass sensors is carried out. Moreover, mode shapes studies are performed. The sensitivity results show better, if the length of the single-wall carbon nanotube is reduced.

The paper presents the results of calculating the angular spectra of light reflection under the condition of excitation of surface plasmons in the Kretschman scheme. The silver layer in this scheme plays the role of a reference material, the minimum in the angular spectrum of which serves as a reference point for the shift of the minimum of the angular spectrum when a layer of the studied biological material is added to the considered layered system, which were melanin and biological tissue. As a result of the work, specific pronounced minima in the angular spectra were obtained, which make it possible to identify these materials with a high degree of accuracy due to the narrow resonance peaks in the angular reflection spectra, which are spaced from the peak in the reflection from the silver film by certain angles. The method contains all the characteristic features of the resonance spectroscopy method; the conditions for the excitation of a surface plasmon at the metal boundary act as resonance conditions.

Methods of electrochemical analysis of biological objects based on the reaction of electro-oxidation/electro-reduction of molecules are presented. Polymer nanocomposite materials that modify electrodes to increase sensitivity of electrochemical events on the surface of electrodes are described. Examples of applications electrochemical biosensors constructed with nanocomposite material for detection of biological molecules are presented, advantages and drawbacks of different applications are discussed.

Scanning helium-ion microscopy (HIM) is an imaging technique with sub-nanometre resolution and is a powerful tool to resolve some of the tiniest structures in biology. In many aspects, the HIM resembles a field-emission scanning electron microscope (FE-SEM), but the use of helium ions rather than electrons provides several advantages, including higher surface sensitivity, larger depth of field, and a straightforward charge-compensating electron flood gun, which enables imaging of non-conductive samples, rendering HIM a promising high-resolution imaging technique for biological samples. Starting with studies focused on medical research, the last decade has seen some particularly spectacular high-resolution images in studies focused on plants, microbiology, virology, and geomicrobiology. However, HIM is not just an imaging technique. The ability to use the instrument for milling biological objects as small as viruses offers unique opportunities which are not possible with more conventional focused ion beams, such as gallium. Several pioneering technical developments, such as methods to couple secondary ion mass spectrometry (SIMS) or ionoluminescence with the HIM, also offer the possibility for new and exciting research on biological materials. In this review, we present a comprehensive overview of almost all currently published literature which has demonstrated the application of HIM for imaging of biological specimens. We also discuss some technical features of this unique type of instrument and highlight some of the new advances which will likely become more widely used in the years to come.

A series of comprehensive studies is performed to optimize the use of radiation technologies in the sterilization and processing of biological objects. Experimental study reveals the nonlinear dependence of the effectiveness of suppressing pathogenic microorganisms on samples of chilled turkey meat on the dose rate with the doses ranging from 0.25 to 6 kGy. Fluorescence fingerprinting reveals no appreciable differences between irradiated and non-irradiated samples.

The design of a thermoelectric refrigerator for short-term storage and transportation of biological substances based on a cascade thermoelectric battery (TEB) is assessed. One feature of the device is the ability to store several types of biological objects with different temperature conditions simultaneously. Relationships between changes in temperature at monitoring points within the device over time at different TEB supply currents are addressed. Organization of the required temperature regime for storage of biological materials can be achieved using standard manufactured TEB.

A novel technological approach based on ion implantation for obtaining nanostructured substrates for the visual characterization of ultrasmall biological objects and microorganisms has been described. By means of argon-ion implantation of silicate glasses through surface masks made of copper wire mesh, periodic microstructures in the form of gratings with mesh sizes of 50 × 50 μm were formed. The novel substrates were tested by scanning electron microscopy and energy-dispersive X-ray analysis, as well as atomic force microscopy, using bacteria of the genera Bacillus and Staphylococcus deposited onto their surface.

Subject and Purpose. Synthesis of biological sorbents has become one of the ways to solve the problem of environment contamination with heavy metals. Today, studying properties of biosorbents with injection of magnetic nanoparticles is important. Thus, injection of magnetic nanoparticles of magnetite (Fe3O4) improves absorption properties of biosorbents. The subject of the present work is magnetic resonance properties of nanoparticles inside biosorbents, such as macromycetes like Pleurotus ostreatus. The purpose is to examine these magnetic resonance properties and analyze the state of magnetite nanoparticles inside Pleurotus ostreatus. Methods and Methodology. The X-band Electron Spin Resonance (ESR) method is employed to register ferromagnetic resonance (FMR) spectra at T = 294 K. TEM-images of magnetic nanoparticles are made in the transmission electron microscope. Mathematical modeling for the properties of the arising clusters of magnetic Fe3O4 nanoparticles inside macromycetes Pleurotus ostreatus is performed using a phenomenological model upon the well-known Kittel equation. A model enhancement is proposed in the case of interacting nanoparticles inside an ellipsoidal magnetic cluster. Results. It has been shown that Fe3O4 nanoparticles are well absorbed by macromycetes and gather into structural clusters regardless of the concentration of magnetic nanoparticles injected. These magnetic clusters of magnetic nanoparticles have ellipsoidal shapes with an aspect ratio of 3:1:1. The developed mathematical model makes it possible to obtain dimensions of magnetic clusters from the FMR spectra and evaluate their shape and mutual magnetic interaction. The mathematical modeling results are in good agreement with TEM-images of these clusters inside Pleurotus ostreatus. As a result of modeling are in good agreement with the TEM-images of these clusters inside Pleurotus ostreatus. Conclusion. The presented results will contribute to the development of non-destructive testing of the state of biological sorbents using magnetic resonance radio spectroscopy methods.

The interface between electronic components and biological objects plays a crucial role in the success of bioelectronic devices. Since the electronics typically include different elements such as an insulating substrate in combination with conducting electrodes, an important issue of bioelectronics involves tailoring and optimizing the interface for any envisioned applications. In this paper, we present a method for functionalizing insulating substrates (SiO

The capabilities of manipulating and analyzing biological cells, bacteria, viruses, DNAs, and proteins at high resolution are significant in understanding biology and enabling early disease diagnosis. We discuss progress in developments and applications of plasmonic nanotweezers and nanosensors where the plasmon-enhanced light-matter interactions at the nanoscale improve the optical manipulation and analysis of biological objects. Selected examples are presented to illustrate their design and working principles. In the context of plasmofluidics, which merges plasmonics and fluidics, the integration of plasmonic nanotweezers and nanosensors with microfluidic systems for point-of-care (POC) applications is envisioned. We provide our perspectives on the challenges and opportunities in further developing and applying the plasmofluidic POC devices.

A new method of forming substrates (devices) with periodic micron surface grids for statistical analysis and visual characterization of ultra-small biological objects and microorganisms is suggested. For this aim an implantation by Ar+ of silicate glasses through surface masks as wire meshes is used to form surface periodic structures in the form of grating with cell sizes of 25 μm and a depth of 100 nm. Testing of novel types of devices was carried out applying scanning electron and atomic force microscopy, as well as EDX analysis using substrates with deposited bacteria as Bacillus subtilis.

To substantiate the quantitative values of the process of destruction of weeds by means of electric impulse and to elucidate the mechanism of damage and the sequence of disturbances that occur in the internal structure of the processed plants, it is necessary to know not only the design of the electrical circuit of the plant tissue substitution but also to have information on the nature of the change in the parameters of the elements of this scheme during electric damage. The presented technique allows (with the help of inexpensive and accessible technical means) to control the damage to the tissues of a weed plant and to calculate quantitative values using developed mathematical apparatus. The analysis shows that the damage to weed plant tissues can be characterized, first of all, by the loss of cell membranes in their semipermeable functions and an increase in the active conductivity of the processed areas of plants. Such changes in the internal structure of plant tissue lead to loss of cell viability in the areas subjected to the electric impulse treatment. The presented analysis fits the current thinking of biophysicists on the electrical damage to the internal structure of biological objects. The technological studies of the process of the electric impulse irreversible damage to plant tissues conducted, based on the analysis presented in the article, allow us to limit the supplied electric energy that makes it possible to make electric impulse weeding an energy-saving means of combating weeds.

The proposed correction allows to refine the surface temperature determined by a standard noninvasive thermographic method based on IR images for the human skin with a nonuniform in depth temperature distribution. The nonuniformity is due to the biophysical necessity of normal functioning of the organism, as well as to a possible presence of pathological processes in certain areas of the body. The measured brightness can be spectral or polychromatic. The value of the correction is analyzed depending on the size, shape, and thermal power of the source of pathology, as well as the depth of its location, thermophysical and optical characteristics of the biological environment.

The biological activity of laser radiation (wavelength, 632.8 nm) when it interacts with human serum albumin is demonstrated. The most noticeable effect of exposure to laser radiation is observed when the energy density is 28.8 J cm−2. It is assumed that three-photon absorption is the main mechanism of biological stimulation.

Detection systems with deferred registration of luminescence signals are promising for performing complex tasks of imaging of biological objects due to their simplicity and low cost. In the present work, β‑NaYF4:Tm3+Yb3+/NaYF4 nanocrystals with anti-Stokes photoluminescence have been used in deferred registration systems. It has been shown that there is a significant time delay between the exciting laser pulse and luminescence signal, which makes it possible to use this class of nanoparticles in the creation of wide-field imaging systems with deferred registration. The possibility of using nanoparticles for detecting a photoluminescence signal in the second transparency window of biotissue has been demonstrated. This system can be based on the resonance excitation and detection of the photoluminescence signal of Yb3+ ions.

Classification of methods and means of laser polarimetry of biological tissues (liquids) is described, methods and means of imaging mueller-matrix polarimetry for reproduction of anisotropic characteristics of biological layers are analyzed. According to the results of the analysis factors of possible increase of reliability of diagnostics of pathological changes of biological objects in application of polarization technologies are determined.

Raman spectroscopy provides a non-invasive, chemically-specific optical imaging of biological objects without relying on endogenous labels. Nonlinear Raman spectroscopy allows non-invasive imaging at much faster speed with an improved spatial resolution and axial sectioning capability. In this report we propose a novel use of nonlinear Raman spectroscopy as a sensor of local nano-environment. Time-resolved coherent anti-Stokes Raman spectrograms are found to be sensitive to small variations of local structural changes, which are not normally observed using conventional Raman spectroscopy.

In recent years, research has been intensively carried out on the applicability of magnetic beads (MBs) and magnetic nanoparticles coupled to biological objects such as red blood cells (RBCs). The magnetoresistance (MR) of a solution of RBCs and MBs (RBCs+MBs) was evaluated when MBs migrated in the presence or absence of an external magnetic field. The pattern of distribution of the MBs, which were homogeneously suspended in deionized distilled water, varied depending on the magnitude of the external magnetic field applied between the Cu electrodes connected to the two terminals. As the magnitude of the external magnetic field is increased or decreased, MBs are split on both sides and evenly mixed, respectively. The ratios (ΔMR/MR) versus an external magnetic field for the solutions of only MBs and a mixed RBCs+MBs were −33.4% and −27.4% at ±30 Oe and ±46 Oe of coercive fields, respectively. These results show that a solution of RBCs+MBs can act like a high-resolution biosensor that detects the oxygenation state of RBCs.

The article is devoted to the study of the possibilities of ultrasonic cavitation inactivation of microorganisms. The possibilities of constructing mobile processing equipment for implementing the technology of ultrasonic cavitation inactivation of harmful and dangerous microorganisms for human health are considered. Two possible ways of increasing the intensity of ultrasonic exposure to biological objects were presented due to the concentration of ultrasonic energy and cavitation treatment in a thin layer on the radiation surface. The results of microbiological analysis as well as recommendations to increase the efficiency of cavitation inactivation of microorganisms had given.

Purpose: Extension of the method of surface plasmon resonance spectroscopy to the case of polarized laser radiation.

A Ti&ndash, 25Nb&ndash, 13Ta&ndash, 5Zr alloy was produced and studied in this work, and plates and wires were made from this alloy. It is shown that the Ti&ndash, 5Zr alloy has the required mechanical properties and a &beta, crystal phase. Microstructures were present on the surface of the alloy with a height of several hundred nm, located at a distance of 1.5&ndash, 2 &mu, m from each other. Ti&ndash, 5Zr was superior to nitinol in terms of the formation of long-living reactive protein species and the generation of reactive oxygen species. Cell cultivation on Ti&ndash, 5Zr alloy surfaces revealed a significant mitotic index (2%) and a small number of nonviable cells (&lt, 5%). The cells were actively attached and spread over the alloy. The biocompatibility of Ti&ndash, 5Zr was verified by experiments on the implantation of the alloy in the form of plates and coiled wires. The surface morphology of the specimens after biological trials was not significantly altered. The experimental data we obtained suggest that Ti&ndash, 5Zr is suitable for potential applications in biology and medicine.

The prehistory, present state, and prospects of LENR and transmutation of stable and radioactive isotopes in growing biological objects are considered in detail. The prerequisites, biological, and physical causes and methods for optimizing the process of isotope transmutation are discussed. Experiments on transmutation of various isotopes (including the production of rare stable isotopes and the deactivation of reactor radioactive waste) are also considered. It is shown that the most likely physical mechanism of LENR in biological systems is connected with the formation of coherent correlated states of interacting particles. This process is accompanied by giant energy fluctuations, which can exist for a long time, sufficient to produce nuclear reactions. This process happens automatically in nonstationary potential nano-wells, which are formed in various biophysical and biochemical processes in growing biological objects—for example, during cell division, at DNA replication, at the entrance to ion channels in plasma membranes, and in other places of growing objects.

The optoacoustic effect leading to excitation of acoustic waves upon absorption of a variable light flux is considered. This effect is of interest from the viewpoint of practical application in biomedical measurements as a promising noninvasive method for diagnostics of biological objects. The results of experimental flow diagnostics based on laser excitation of an optoacoustic signal in liquid are presented. An algorithm of the flow cytometry procedure is developed.

The paper presents results of experimental biotechnological research that has been carried out at the Nanotechnological Center of the Central Research Institute of Structural Materials Prometey. This includes development of gradient functional coatings (bactericidal, anticorrosion, catalytically active) and defense systems for biological objects against negative influence of magnetic and electromagnetic radiation; high-speed shock wave treatment of medicines, phytomaterials, and alimentary, fodder, and medical products; and laser technologies for creating hybrid biomimetic compositions.

Thermal design of devices for safe storage of biological objects was performed. Three-dimensional models of a safe storage device with multi-layer walls were constructed. Computational experiments with subsequent analysis of the temperature distribution over the computational domain and the time dependence of various parameters were performed.

A possibility of detecting biogenic gases by the laser optoacoustic gas-analysis method is shown. The construction and specifications of instruments, developed for this purpose, are described. Examples of the analysis of gas samples of various biological objects, like air, expired by patients, suffered from different illnesses, and residual gases in the wood of year rings of conifers are given together with recommendations on applying the received information.

A new approach to the use of nanotubes as an alloying tool for living biological objects is proposed. The basis of the mechanism of doping is chemical detonation in the nanotube. A procedure for the accelerated calculation of nanotube parameters for the purpose of doping is proposed. The possibilities of parallel programming in calculating the parameters of a detonation gas mixture are shown.

The features of the X-ray microtomography method are considered. The possibility of using the method for the diagnosis of biological objects is described. The results of the study of the internal structure of a laboratory rat and jaw of a man with metal structures are presented. Evaluation of the necessary technical parameters for the possibility of using the method in medicine was performed.

Designing radiophysical devices for investigating the effect of microwave radiation on biological objects is one of the main directions in applied modern radio-electronics. An installation for investigating the radiophysical microwave radiation effects on laboratory animals has been developed, with the frequency being 915 MHz, power of electromagnetic radiation being 10 μW/cm2. The results obtained demonstrate the survival rate of mice with tumor under the influence of electromagnetic field.

Using acoustoelectronic sensors not containing sensitive coatings, we studied a series of microbiological preparations: yeast cells and bacteria, as well as virus particles, immobilized in hydrogels of different concentration. The obtained measurement data on the acoustic characteristics make it possible to (1) reveal the presence of biological objects in both fluid media and agarose-based hydrogels of various concentration; (2) establish the physical mechanism that results in acoustoelectronic detection; (3) evaluate changes in the concentration of biological objects and their electric conductivity. The data confirm the possibility of applying the acoustoelectronic technique to detect microbiological objects and observe their growth in hydrogel media. We discus the limitations and drawbacks of the acoustoelectronic technique.

Superior spectral sensitivity and functional abilities of anisotropic, instead of the usually used spherical, noble metal nanoparticles, allow development of new surface-enhanced Raman spectroscopy (SERS) approaches to analyse biological objects. We found and resolved for the first time the particular risks of survival of silver nanoparticles in different salines to succeed in recording the SERS spectra of intact erythrocytes as an important family of living cells. The ensemble of nanoplatelets with varied shapes and sizes grants multispectral absorption of laser irradiation since a fraction of the nanoparticles with a given position of a plasmonic band always exists in such a mixture, thereby providing an effective SERS amplification. At the same time, fast recrystallization of anisotropic silver nanoplatelets occurs in a standard chloride-based saline, being important to keep the erythrocytes alive but neglecting the benefits of the silver platelets as the most versatile and prospective components of SERS sensors. Substitution of chlorides with nitrates keeps both the intact cells and anisotropic nanoparticles safe on biocompatible cellulose SERS scaffolds containing the mixture of silver nanoplatelets thus promoting the development of new SERS devices for biomedical diagnostics.

Nanostructures research plays a crucial role in the transformation of breakthrough scientific ideas into next-generation technology. In the way that silicon revolutionized the microelectronics industry, plasmonic nanostructures can greatly impact on the field of analytical instruments for molecular analysis of materials, even biological objects. Currently, research in the plasmonics has been faced the problem of choosing the optimal plasmonic nanostructures in order to realize useful devices. Usually, metal components such as gold, silver and copper serve for working elements of plasmon-active surfaces, which have a number of advantages in comparison with other materials. However, on the stage of devises design, the choice even between three different metals causes great difficulties. In order to take the first steps to solve this problem, here we consider the criteria for plasmon-active metals choice, and also give examples of Au, Ag, and Cu nanostructures obtained by the controlled self-assembly in limited pore volume of the SiO 2 /Si template for SERS applications.

The tendency of arch-trapped microwave propagation at curved surfaces is a kind of diffraction which needs more attention in the development of measurement systems, from the oil industry to the investigations using antenna applicator systems for biological objects. We develop equations for propagation in very Iossy substances in metal pipes. Similar such propagation occurs at the periphery of rounded objects in air, where also surface wave effects occur and can cause measurement problems. We show a modified contacting antenna applicator minimizing arch-trapped as well as surface waves.

Different steady-state fluorescence spectroscopy approaches are investigated to obtain the highest quality spectral information from biological objects. Synchronous fluorescence spectroscopy (SFS) leads to improved spectral resolution in detection of multi-compound and complex systems, where several fluorophores with similar excitation and emission properties have place. In this study SFS was used to detect and differentiate normal and neoplastic skin and gastrointestinal lesions.

A laser medical device has been created to conduct an exact photodestruction of the vascular formations of the skin and subcutaneous tissue. Conducted studies on model biological objects for confirmation the possibility of realizing the optimal parameters of laser radiation providing photodestruction of hemoglobin containing tissues.

Stimulated Raman scattering (SRS) is non-linear vibrational spectroscopic technique with sub-millisecond sampling times allowing to perform video rate imaging on biological objects including even few tens of cells simultaneously. In this work SRS was used for in vivo study of cell division in zebrafish embryo in order to get insight into temporal evolution of the related processes.

The possibility of noninvasive detection of magnetic particles in biological objects has been investigated. It has been found that magnetic particles, including magnetite, hematite, and catalytic iron particles in carbon nanotubes, can be detected by ultrasensitive magnetic field sensors with resolutions of 10−8-10−14 T. This research direction is shown to be promising for noninvasive monitoring of organs, implants, prosthesis, and other elements of biological systems.

This paper presents the results of research aimed at determining the effect of an oscillating magnetic field on water substrates of various biomass wastes. The methodology of modeling physical processes in substrates is presented. The results of experimental studies of water substrates in the magnetic field of permanent magnets on a laboratory installation are given. The recommendations on the use of the presented research results are formed.

Optic properties of cholesterol liquid crystals promote their use as active elements of optic sensors for quantitative and qualitative evaluation of biological substances. The change of spectral characteristics of cholesterol liquid crystals occurs during contact with biological substances, which is the basis for detection, identification and diagnostics of biological objects. Spectral characteristics of liquid crystal substances based on cholesterol liquid crystal BLO-62 with admixture of nematic liquid crystal 5CB and their change on introduction of aqueous solutions of pepsin and trypsin have been investigated. Concentration of pepsin (6%) and trypsin (10%) in aqueous solutions and their content in liquid crystal medium has been optimized to achieve maximal value of spectral sensitivity coefficient. The optical converter was developed with cholestric liquid crystal as a sensitive element. For the enzymes investigation the structural scheme of the sensor device is developed and the peculiarities of the information signal formation are presented. The sensor operation algorithm is developed to measure different types of enzymes.

It is analyzed ways and methods of contrast improvements of biological objects images, which are created by television optical microscope. Advantages of TV scanning microscope usage for biological objects images formations are reviewed. Methods of research stages which allow to improve microscope parameters are shown in this paper.

A model of a device for studying the effects of high-voltage electric fields on biological objects in aqueous solution, showing the range of output parameters, is described. A scheme for the device was developed, on which basis an existing experimental model was assembled for subsequent testing in a laboratory setup.

A method for recording the metabolic frequencies lying in the extremely high-frequency range, which are characterized by changes in the admittance of biological objects and lead to changes in the activity of their life processes, is proposed. The measuring facility uses the “pass-through” method to identify these frequencies in special containers with biological media. It is shown that the metabolic changes may occur owing to chiral-dependent effects, which take place in the volumes of these media. Performed calculations illustrate the contribution of chiral components to the output admittance of media for different concentrations of liquid.

Biomedical studies for identifying response parameters of biological objects correlated with phototherapeutic effects are discussed. Investigations were performed during phototherapeutic treatment of patients with post-mast-ectomy syndrome who underwent surgical removal of a mammary gland affected by cancer. Matrix LED emitters with wavelengths from 660 to 860 nm were used. To determine the correlated response parameters, a two-channel digital thermometer and a two-channel photoplethysmograph were used. Both amplitude of the pulse curve and temperature of the surface tissues can serve as correlated response parameters. By monitoring these parameters, feedback systems can be created that enable individual dose setting of optical exposure for an individual phototherapeutic procedure, as well as for the whole course of treatment.