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The micromechanical methods, among which optical trapping and atomic force microscopy have a special place, are widespread currently in biology to study molecular interactions between different biological objects. Optical trapping is reported to be quite applicable to study the mechanical properties of surface structures onto bacterial (pili and flagella) and eukaryotic (filopodia) cells. The review briefly summarizes the physical basis of optical trapping, as well as the principles of calculating the van der Waals, electrostatic, and donor-acceptor forces when two microparticles or a microparticle and a flat surface are used. Three main types of model systems (abiotic, biotic, and mixed) used in trapping experiments are described, and the peculiarities of manipulation with living (bacteria, fungal spores, etc.) and non-spherical objects (e.g., rod-shaped bacteria) are summarized.

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.

Stereology is the method of choice for the quantitative assessment of biological objects in microscopy. It takes into account the fact that, in traditional microscopy such as conventional light and transmission electron microscopy, although one has to rely on measurements on nearly two-dimensional sections from fixed and embedded tissue samples, the quantitative data obtained by these measurements should characterize the real three-dimensional properties of the biological objects and not just their “flatland” appearance on the sections. Thus, three-dimensionality is a built-in property of stereological sampling and measurement tools. Stereology is, therefore, perfectly suited to be combined with 3D imaging techniques which cover a wide range of complementary sample sizes and resolutions, e.g. micro-computed tomography, confocal microscopy and volume electron microscopy. Here, we review those stereological principles that are of particular relevance for 3D imaging and provide an overview of applications of 3D imaging-based stereology to the lung in health and disease. The symbiosis of stereology and 3D imaging thus provides the unique opportunity for unbiased and comprehensive quantitative characterization of the three-dimensional architecture of the lung from macro to nano scale.

Certified reference materials (CRM) composed of propyl (11383-2019) and isopropyl (11384-2019) alcohols solutions were created for validation of measurement procedures and control of measurement errors of measurement results of mass concentrations of toxic substances (alcohol) in biological objects (urine, blood) and water. Two ways of establishing the value of the certified characteristic – mass consentration of propanol-1 or propanol-2 have been studied. The results obtained by the preparation procedure and comparison with the standard are the same within the margin of error.

Label-free characterization of cell subpopulations is a very promising biomedical approach. Nowadays, there are several label-free methods based on different physical properties such as size, density, stiffness, etc. allowing the characterization of biological objects. However, fluorescence properties are the most suitable feature for the label-free study of tissue and cells. Understanding the autofluorescence level peculiarities of normal and pathological / live and dead cells can become a helpful tool for cells' metabolic activity, viability evaluation, and diagnostics of a number of diseases. In this study, we applied a series of mouse cell lines (RAW 264.7 - macrophages, L929 - fibroblasts, C2C12 - myoblasts, and B16-F10 - melanoma) to compare cell autofluorescence of live and dead cells under 488 nm laser excitation and found the difference between their autofluorescence depending on a cell state and type.

Novel luminescent derivatives of benzanthrone were obtained in nucleophilic substitution reactions of 3-(2-chloroacetamido)-benzanthrone with a number of heterocyclic amines. The structures of the obtained compounds were confirmed by spectral data. Target products, due to pronounced luminescent properties, can be used to visualize biological objects.

Atomic absorption spectrometry (AAS) is one of the most widely used and available methods for analysis of substances and materials. It allows one to determine about 70 elements from the periodic table and is characterized by rapidity, high accuracy and sensitivity, as well as simplicity of analytical techniques. A feature of AAS is simultaneous determination of only one element due to the use of a measurement design with a line source (hollow-cathode lamps, high-frequency electrodeless lamps, optical quantum generators, etc.). To make AAS more competitive, the first commercially available continuum source atomic absorption spectrometer was designed in 2004. Unique analytical capabilities of the new instruments found application first of all in the analysis of food, pharmaceuticals, waste and drinking water, oil and petrochemicals, biological objects, etc. This review covers publications on the application of continuum source AAS in analytical chemistry and provides a development outlook of the method.

Fluorescence change systems that can respond to biological objects have attracted attention for use as biological probes and sensors. In this study, we report emission enhancement in a fluorescent aggregate composed of amphiphilic donor-acceptor dye molecules. The emission efficiency of the aggregate was reduced upon introducing a hydrophilic galactopyranose moiety, because of the decrease in the aggregate stability, which in turn was due to disruption of the hydrophilicity-hydrophobicity balance. In contrast, emission enhancement could be achieved by treatment with β-galactosidase, as a result of the removal of the galactopyranose moiety. The change in aggregate stabilization based on the hydrophilicity-hydrophobicity balance leads to the emission enhancement into detectable β-galactosidase activity.

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.

This review addresses questions of the specific characteristics of power supply to implanted devices (ID), including the service life of supply elements and the level of power consumption of contemporary devices, the acceptable weight and size characteristics of ID, and priority areas for implantation. Known methods of energy transmission and transformation are compared and the ranges of potential specific power for these are determined −0.1-100 mW/cm2 for wireless energy transmission, 0.0001-0.1 mW/cm2 for transformation of energy for sources specific to biological objects, and less than 0.0001 mW/cm2 for isotope power sources.

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.

A device was developed for searching of optimal parameters for the treatment of biological objects by an alternating magnetic field, where the optimal parameters are determined through automated analysis of the dependencies of the physical characteristics of biological liquids obtained from those biological objects on the frequency and strength of the field.

A method for determining and correcting distortions in spectral-domain optical coherence tomography images caused by medium dispersion was developed. The method is based on analysis of the phase distribution of the interference signal recorded by an optical coherence tomography device using an iterative approach to find and compensate for the effect of a medium’s chromatic dispersion on point-spread function broadening in optical coherence tomography. This enables compensation of the impact of medium dispersion to an accuracy of a fraction of a radian (units of percent) while avoiding additional measurements and solution of the optimization problem. The robustness of the method was demonstrated experimentally using model and biological objects.

Promising biological objects containing the maximum amounts of lipids were selected for further study based on an analysis of published studies on the quantitative and qualitative composition of lipids accumulating in microalgae. The genera Navicula and Isochrysis were found to be most optimal for liquid biofuel production because they contained the maximum percentage of triacylglycerides in the total lipids. Freshwater species of these microalgae genera can be considered most suitable for cultivation in CFD bioreactors as a primary product of biofuel production. Innovative methods using vortex devices are proposed for removing the algal oil.

The paper considers technical implementation of the devices for examining the energy state of the body’s meridian structures based on analog front-end (AFE) interfaces used for measuring the impedance of biological objects. The application of AFE chips improves the accuracy of measurements, while reducing the cost of the devices for reflex diagnostics.

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 low-coherence interference microscope arrangement based on a common path shearing interferometer is proposed to obtain differential phase patterns of biological objects. The phase stepping method is used to reconstruct such patterns. Results are presented for experiments to study human blood erythrocytes.

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.

The possibility of expanding diagnostic capabilities in electrical impedance imaging using probing signals of different shape is described. A block diagram of a hardware–software complex that implements this feature is presented. Additionally, the results of test experiments on both biological objects and in equivalent circuits are presented.

A microwave radio thermometer for determining the temperature of local sections inside a biological medium is described. The basic operating principle is a modification of the zero-measurements method.

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.

Generation of the pulsed magnetic fields that are 5–6 orders of magnitude higher than the geomagnetic field requires switching of high pulsed currents. As a result, the occurrence of the Joule heating in the inductors limits the possible biological applications of the pulsed magnetic fields. This work is focused on the investigation of the generated Joule heating inside the inductors of different shapes. The analysis of the Joule heating influence on the vitality of biological objects during magnetic permeabilization is presented. The biological objects that are used in the study are the pathogenic fungi Candida albicans and Trichophyton rubrum, which are the common cases for human infections. The finite element method analysis of the pulsed inductors and the experimental results with the selected pathogenic fungi are overviewed. The limitations of the magnetic permeabilization technique due to the generated Joule heating are identified.

Contemporary biotechnical systems combining biological and technological elements with a given function are discussed. In addition to convenient control systems, such biotechnical systems provide studies of bioorganisms and biological materials of any origin, as well as their environment. A special class of biotechnical systems (channels connecting various elements) is discussed in particular. Basic problems of elucidation of properties of biological objects are formulated.

Photoactivated ("caged") fluorescent dyes are modern tools for structure and function studies of cell membranes and subcellular organelles. Recently synthesized precursors of rhodamine fluorescent dyes (abbreviations PFD813 and PFD814) important for microscopic probing of biological objects have been studied in solution. In order to characterize the behavior at interfaces, monolayers of PFD813 and PFD814 on water have been formed and investigated. The interactions of these precursors with the biomembrane component dimyristoylphosphatidylethanolamine in monolayers at the air-water interface and after transfer to glass plates have been studied by measuring monolayer parameters and spectroscopic properties before and after photo-chemical formation of the fluorescent rhodamine dyes Rho813 and Rho814, respectively.

We consider peculiarities in the use of an interference microscope in the research of biological objects (cells) and measurement of the parameters of homogeneous, nonhomogeneous, and dynamic biological micro-objects.

A simple recurrent equation is proposed as a model describing acute toxicity in homologous series of organic compounds in relation to various biological objects. The recurrent model of toxicity provided better extrapolation than linear and parabolic models. Plotting of The coefficients of recurrent equations plotted on planes defined by these coefficients for types of chemical compounds allowed the nonspecific or specific nature of toxicity in homologous series to be identified. Similar visualization in relation to different types of biological objects allowed toxicological relatedness to be identified on the basis of the distances between them. These results may provide grounds for creating computer programs predicting the acute toxicities of new chemical compounds on the basis of QSAR approaches.

Radiofrequency exposure at the mobile connection frequency (1 GHz) at different energy flow densities, 5 μW/cm(2)(2-fold below the maximum permissible level) and 50 μW/cm(2)(5-fold surpassing this level), caused a reduction of motor activity in unicellular hydrobionts Spirostomum ambiguum Ehrbg infusoria. In all cases, the effect was similar by the intensity and developed in a jump-wise manner after exposure of a certain duration, after which did not increase with prolongation of the exposure. The duration of radiofrequency exposure safe for the object varied significantly: 8-9 h and 10 min at 5 and 50 μW, respectively. These innovation data on harmful biological effects of very low radiofrequency exposure (5 μW/cm(2)), the threshold form of biological reaction, presence of "safe" periods of exposure, and the data demonstrating a clear-cut relationship between these periods and energy flow density are interesting from theoretical viewpoint and in connection with the problem of evaluating permissible levels of radiofrequency exposure of biological objects.

We have analyzed the feasibility and expediency of using a probabilistic neural network as a classifier for processing and interpreting data obtained using a biosensor we have developed that is based on whispering-gallery-mode optical resonance. We have established that the probabilistic neural network makes it possible to correctly classify the biological compounds under study with average 97.3% probability.

The metrological parameters of a phase-monitoring system were studied. The ability of this system for monitoring the state of biological objects (dental tissue) was demonstrated. The shift vector was used to test the accuracy of the specklegram processing method. Dental tissue under load was experimentally studied. Projections of the shift vector in loaded dental tissue along OX and OY were measured.

The coherent phase microscopy (CPM) provides a convenient and non-invasive tool for imaging cells and intracellular organelles. In this article, we consider the applications of the CPM method to imaging different cells and energy-transducing intracellular organelles (mitochondria and chloroplasts). Experimental data presented below demonstrate that the optical path length difference of the object, which is the basic optical parameter measured by the CPM method, can serve as an indicator of metabolic states of different biological objects at cellular and subcellular levels of structural organization.

A new method of protection against radiation emission of mobile cell phones is described. The results of experimental testing of the effect of electromagnetic emission of a cell phone on a test-object (daphnia) are discussed. The results of testing of the device for protection against radiation emission of mobile cell phones are considered. This device was demonstrated to provide effective protection against radiation emission of mobile cell phones.

Successful development of ultra-sensitive molecular imaging nanoprobes for the detection of targeted biological objects is a challenging task. Although magnetic nanoprobes have the potential to perform such a role, the results from probes that are currently available have been far from optimal. Here we used artificial engineering approaches to develop innovative magnetic nanoprobes, through a process that involved the systematic evaluation of the magnetic spin, size and type of spinel metal ferrites. These magnetism-engineered iron oxide (MEIO) nanoprobes, when conjugated with antibodies, showed enhanced magnetic resonance imaging (MRI) sensitivity for the detection of cancer markers compared with probes currently available. Also, we successfully visualized small tumors implanted in a mouse. Such high-performance, nanotechnology-based molecular probes could enhance the ability to visualize other biological events critical to diagnostics and therapeutics.

Currently available data on clinical use of therapeutic photomatrix systems (TPMS) used for irradiation of extensive body areas are summarized. A therapeutic photomatrix system is implemented as an array of visible of infrared light emitters. The problems of photomatrix equipment interaction with biological objects are discussed. The main results of the clinical use of photomatrix equipment for treatment of a number of diseases are considered. Four main variants of clinical application of photomatrix equipment are considered: use of TPMS alone; use of TPMS in combination with medicamentous treatment; use of TPMS in combination with other physiotherapeutic procedures; use of TPMS in combination with other physiotherapeutic procedures and medicamentous treatment.

Associations among biological objects such as genes, proteins, and drugs can be discovered automatically from the scientific literature. TransMiner is a system for finding associations among objects by mining the Medline database of the scientific literature. The direct associations among the objects are discovered based on the principle of co-occurrence in the form of an association graph. The principle of transitive closure is applied to the association graph to find potential transitive associations. The potential transitive associations that are indeed direct are discovered by iterative retrieval and mining of the Medline documents. Those associations that are not found explicitly in the entire Medline database are transitive associations and are the candidates for hypothesis generation. The transitive associations were ranked based on the sum of weight of terms that co-occur with both the objects. The direct and transitive associations are visualized using a graph visualization applet. TransMiner was tested by finding associations among 56 breast cancer genes and among 24 objects in the calpain signal transduction pathway. TransMiner was also used to rediscover associations between magnesium and migraine.

We have presented an overview of the literature and of our experimental data on the influence of electromagnetic radiation in the submillimeter spectral region on biological objects of molecular, cellular, and organism levels. Possible physical mechanisms involved and the reasons for limited development of the research in this spectral range are discussed.

A limited-coherence interferometer system for examination of biological materials has been developed. The microrelief profile of human skin was probed in vivo. It was found that the limited-coherence interferometer system can be used as an optical tomograph. Oil penetration into wrist skin subsurface layer was measured using this system.

The potential for the study and determination of the optical constants of strongly scattering biological objects using spectroscopic analysis of repeated attenuated total internal reflection (ATR) is considered. The optical circuits of repeated attenuated total internal reflection adapters intended for joint operation with infrared-range spectrophotometers are presented.

For studying the mechanism of the functioning and metabolism of progesterone, Semax, and Taftsin derivatives, a procedure was developed for their determination in complex biological systems. The labeling procedure was developed, and labeled analogs of these compounds, required as references, were prepared.

Background Imaging methods are used widely to understand structure of brain and other biological objects. However, sample penetration by light microscopy is limited due to light scattering by the tissue. A number of methods have been recently developed to solve this problem. In one approach (SeeDB) simple procedure for clarifying brain samples for imaging was described. However, this method is not compatible with immunostaining approach as SeeDB-prepared tissue is not permeable to the antibodies. Another technique for clearing brain tissue (CLARITY) was optimized for immunochemistry, but this method technically much more demanding than SeeDB. Results Here we report optimized protocol for imaging of brain samples (CLARITY2). We have simplified and shortened the original protocol. Following hydrogel fixation, we cut brain tissue to 1–1.5 mm thick coronal slices. This additional step enabled us to accelerate and simplify clearing, staining and imaging steps when compared to the original protocol. We validated the modified protocol in imaging experiments with brains from line M Thy1-GFP mouse and in immunostaining experiments with antibodies against postsynaptic protein PSD-95 and striatal-specific protein DARPP32. Conclusions The original CLARITY protocol was optimized and simplified. Application of the modified CLARITY2 protocol could be useful for a broad range of scientists working in neurobiology and developmental biology.

A novel approach based on atomic force microscopy (AFM) for exploring the elastic properties of the membrane-skeleton complex in living cells is presented. Three major elements constitute the basis for the proposed method: (a) Pulling the cell membrane by increasing the adhesion of the tip to the cell surface provided by the appropriate tip modification; (b) Measuring force-distance curves with the emphasis on the selection of the appropriate withdraw regions for analysis; and (c) Fitting of the theoretical model based on the bending deformation of an elastic plate to the experimental curve in the withdraw region, prior to the detachment point of the tip from the cell membrane. This approach, applied to human erythrocytes, suggests a complementary technique to the commonly used indentation method. The presented method enables us to avoid certain important problems relating to the measurements of elastic characteristics of biological objects by the indentation technique. Firstly, in the range of the pulling technique, it is not necessary to define a “point of contact”. A spurious definition of this point can produce significant errors in the estimation of elastic constants. Secondly, the problem of interference with the substrate is eliminated in the AFM pulling technique. The last feature is important when probing the elastic properties of thin soft samples like a thin flat cells or protein layers.

We propose and tested a method for studies of native blood cells by atomic-force microscopy in a humid chamber preserving viability, size, and shape of biological objects. The method has some advantages over scanning in a liquid cell: it allows studying non-fixed blood samples in the form of suspension of live cells and excludes mechanical and chemical influences on the cells.

A nitrogen cryosprayer and a liquid-nitrogen-cooled cryodestructor are described. They are general-purpose experimental devices designed for fast cooling (freezing) of biological objects, in particular, tissues of living organisms.

We developed “IKVOBAN-U” composite polymer implants to replace defects in bony tissue and fill large bone cavities. The presence of piezoelectric properties in the developed implants whose parameters are close to those of biological objects is revealed. Tests carried out on animals and the use of model media showed that the piezoeffect is preserved after prolonged holding in these media.

The dissipation of a microwave field in an inhomogeneous plane layer covered by external semitransparent screens is investigated. It is shown that use of the screens makes it possible to control the dissipation process: to displace the nodes and antinodes of the loss power density and to increase and decrease its values at the antinode points. The reported results can be of help in hyperthermia of biological objects in cancer treatment.

The molecular revolution and the development of biology-derived industry have led in the last fifty years to an unprecedented “leap forward” of life sciences in terms of experimental data. Less success has been achieved in the organisation of such data and in the consequent development of adequate explanatory and predictive theories and models. After a brief historical excursus inborn difficulties of mathematisation of biological objects and processes derived from the complex dynamics of life are discussed along with the logical tools (simplification, choice of observation points etc.) used to overcome them. “Autistic”, monodisciplinary attitudes towards biological modeling of mathematicians, physicists, biologists aimed in each case at the use of the tools of other disciplines to solve “selfish” problems are also taken into account and a warning against derived dangers (reification of monodisciplinary metaphors, lack of falsification etc.) is given. Finally “top-down” (deductive) and “bottom up” (inductive) heuristic interactive approaches to mathematisation are critically discussed with the help of a serie of examples.

Water is the medium in which all processes of vital activity, biochemical and biophysical reactions, occur. The information properties of water are most important to understand. The information properties of water were studied in experiments of Prof. Imoto Masaru (Japan) (10). Droplets of water in these experiments were frozen and examined using an optical microscope and builtin photographic camera. The structure of water crystals was unambiguously demonstrated to depend on the informa� tion factor affecting water before freezing. For example, Prof. Imoto Masaru studied the effect of music on the structure of snowflakes. A container with distilled water was placed between two musical speakers for several hours. Then the sonicated water was frozen. The structure of the resulting snowflakes depended of the type of music (Fig. 1). Studies of J. Grander on the noncontact biological effect of water are of considerable interest (1). Tap water treated using the method of Grander was found to be "vitalized". Such treatment caused alkalization of water and modified its redox potential. The water treated using the method of Grander had a remote effect on untreated water and biological objects. The effect was not prevented by a metal screen. There is still no physical explanation of this phenomenon. Therefore, the biological effects of active water were assessed using standard methods of bio� logical testing. The water treated using the method of Grander reduces concentrations and lifetime of aqueous bacterial microflora: gramnegative microflora, salmonellas, coli� form bacteria, thermotolerant bacteria, and allochthonic and autochthonic microflora. The water treated using the method of Grander had a pronounced therapeutic effect on volunteer subjects, the effect vanishing within two days after cessation of water intake. The therapeutic effect of water treated using the method of Grander may last for up to 3 weeks, depending on specific method of treatment (5). Similarly, water is able to process information of other types. In the 1980s Academician V. P. Kaznacheev demonstrated experimental evidence of transfer of bio� logical information from one aqueous medium to anoth� er (3). The following experimental scheme was used: one chamber contained cells infected by virus; another cham� ber contained cells uninfected by the virus. The chambers were sealed and there was only optical contact between the cambers. The death rate of infected cells was meas� ured in chamber 1. Later, a similar process was observed in chamber 2.