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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 distribution of free water and water associated with molecules of biological matter determines its state. The electrophysical properties of free and bound water are significantly different, and the relaxation frequency of molecules lies in the microwave range. Therefore, microwave methods of measurement are effective. The microwave sensor circuit is analyzed, for which it is possible to create a rigorous analytical model. The results of calculations of the electromagnetic field components and the transfer function of the sensor are discussed, and the dimensions of its working area are estimated.

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.

This article discusses the possibility of applying the principles of Fourier polarimetry to the study of optically anisotropic networks of biological objects. The possibility of using statistical analysis to study the coordinate distributions of polarization states in the Fourier plane, the field of scattered laser radiation by virtual polycrystalline networks is demonstrated. The polarization-inhomogeneous structure of the Fourier transform of laser images of ensembles of optical-anisotropic biproenescent crystals has been revealed.

The radiophysical installation designed to study the effect of microwave radiation on biological objects, with an operating frequency of 915 MHz, was used to influence mice with Ehrlich ascites carcinoma. The laboratory animals were exposed to microwave EM radiation of different intensity. The experimental results obtained revealed the dependence of the tumor growth on the intensity of the microwave radiation exposure.

Plenoptic cameras use arrays of micro-lenses to capture multiple views of the same scene in a single compound image. They enable refocusing on different planes and depth estimation. However, until now, all types of plenoptic computational imaging have been limited to visible light. We demonstrate an x-ray plenoptic microscope that uses a concentrating micro-capillary array instead of a micro-lens array and can simultaneously acquire from one hundred to one thousand x-ray projections of imaged volumes that are located in the focal spot region of the micro-capillary array. Hence, tomographic slices at various depths near the focal plane can be reconstructed in a way similar to tomosynthesis, but from a single x-ray exposure. The microscope enables depth-resolved imaging of small subvolumes in large samples and can be used for imaging of weakly absorbing artificial and biological objects by means of propagation phase-contrast., Comment: The following article has been accepted by Applied Physics Letters

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 article discusses the effect of microwave radiation on the seeds of Scots pine (Pinus sylvestris L.). The aim of the research is to increase the efficiency of pre-sowing treatment of seeds with Ultra-high-frequency radiation (UHF) radiation, allowing one to increase the standard planting material yield and reduce its cultivation time. The specificity of enzyme systems for stressing effects is revealed, the dynamics of their change in the period after irradiation is ambiguous and depends on the time of irradiation. The stimulating and lethal doses of radiation are determined. The results show seed treatment with stimulating doses causes reversible changes in the structure and function of enzymes. The regularities and model of the impact of UHF radiation as a stimulating factor on seed viability are established. When exposed to stress factors (radiation), an increase in the activity of enzymes is observed, leading to the excitation or inhibition of growth processes at the first stages of development. As a result, a stimulating effect arises – the germination of seeds increases, the growth of seedlings in height increases, or depressing – the germination decreases and the growth of seedlings slows down.

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.

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.

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.

The chapter covers investigations of methods and means for the protection of biological and technical objects from the influence of electromagnetic (EM) irradiations both of the natural and artificial (anthropogenic) origin. Detailed are the theoretical and experimental data on the physical mechanisms and consequences of influences of these irradiations on the biological objects. Under consideration are the various designs of the reflective and absorbent protective screens. Special attention is attributed to the peculiarities of formation of multilayer special purpose screens for protection from the static magnetic fields, low frequency (LF) and pulse electromagnetic irradiations, as well as quasi-stationary fields.

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.

To image biological objects using coherent X-ray diffraction (CXDI), the resolution limitation is mainly resulted from insufficient photon flux at current XFEL facilities. In this report, a photon-flux master curve of particle detection is generated from single shot computer simulation of different biological particles in Protein Data Bank and EMDataBank. The master curve can be applied to estimate scatted X-ray intensity and guide the design of CXDI experiments.

Holographic tomography (HT) is an advanced label-free optical microscopic imaging method used for biological studies. HT uses digital holographic microscopy to record the complex amplitudes of a biological sample as digital holograms and then numerically reconstruct the sample’s refractive index (RI) distribution in three dimensions. The RI values are a key parameter for label-free bio-examination, which correlate with metabolic activities and spatiotemporal distribution of biophysical parameters of cells and their internal organelles, tissues, and small-scale biological objects. This article provides insight on this rapidly growing HT field of research and its applications in biology. We present a review summary of the HT principle and highlight recent technical advancement in HT and its applications.

An original experimental stand is presented, aimed at studying the impact of high-energy protons, produced by the laser-plasma interaction at a petawatt power level, on biological objects. In the course of pilot experiments with the energy of laser-accelerated protons up to 25 MeV, the possibility is demonstrated of transferring doses up to 10 Gy to the object of study in a single shot with the magnetic separation of protons from parasitic X-ray radiation and fast electrons. The technique of irradiating the cell culture HeLa Kyoto and measuring the fraction of survived cells is developed. The ways of optimising the parameters of proton beams and the suitable methods of their separation with respect to energy and transporting to the studied living objects are discussed. The construction of the stand is intended for the improvement of laser technologies for hadron therapy of malignant neoplasms.

The problem of digital holographic imaging of optically transparent objects in arbitrary spectral intervals is discussed. An optical scheme based on Mach−Zehnder interferometer with acousto-optic filtration of broadband light is proposed, and an experimental setup is described. Digital holograms of test patterns and real biological objects are presented.

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.

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 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.

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.

Two methods of using the X-pinch as a source of X-ray radiation for radiography of biological objects are presented. X-pinches are found to be a very flexible method for generation of radiation over a wide spectral range and provide a high spatial and temporal resolution.

Of great interest for the researches is the influence of electromagnetic emission on biological objects. This paper describes the effect of far-infrared radiation on the process of growth of A.laidlawii cells as a function of culture age.

We demonstrate a source of high power nanosecond RF pulses based on gyromagnetic nonlinear transmission line. The source is designed to explore the exposure of different biological objects to strong RF fields in an air filled rectangular waveguide loaded onto ethanol RF load. The RF pulse amplitude can be varied by 52 dB, reaching a maximum value of nearly 40 kV/cm and decreasing to tens of V/cm. The RF pulse amplitude is controlled by decreasing the incident pulse amplitude from the high voltage driver. The duration of RF pulses lies in the range from 4 to 25 ns and the frequency from 0.6 to 1.0 GHz.

Acousto-optic Bragg imaging is a technique that uses the interaction of light with ultrasound to optically image obstructions in acoustical fields. Existing reports of acousto-optic Bragg imaging based on transmission of acoustic fields through obstructions exhibit strong acoustic impedance mismatches manifested by poor image quality and missing details of physical structures of obstructions. In this work, the image quality was improved to exhibit detailed physical structures of an object by using an improved Bragg imaging system described in Sec. III below. This paper investigates the possibility of extending an acoustic Bragg imaging technique in transmission mode to image animal or plant tissues; a small azalea leaf is used as an illustration in this case. The Bragg image produced clearly shows the veins of the vascular azalea leaf serving as a proof of concept for cost-effective potential application of acoustic Bragg imaging of biological objects in the medical field. Moreover, acousto-optic Bragg imaging is potentially harmless to biological cells and is sensitive to density and elastic variations in the tissue.

Acoustic absorption has been measured in a series of biological tissue specimens—porcine muscle, renal and fat tissues—by the standard insert-substitution method, as well as by ultrasonic phase conjugation. Comparison of the experimental results and revealed differences confirm the promise of using phase conjugate waves to measure acoustic losses in biological objects. It is demonstrated that in inhomogeneous tissues, the phase conjugation method makes it possible to obtain a more reliable estimate of dissipative losses.

A new optical scheme for the microscopic investigation of biological objects is proposed, which combines principles of the optical-coherence and spectral microscopy. The proposed system is based on the acousto-optic filtration of images in the reception channel of a microinterferometer. A prototype of the instrument has been manufactured and it has been demonstrated that the acousto-optic filtration does not violate the interference of two beams carrying images, which makes it possible to extract information both about three-dimensional spatial features and about spectral properties of the object studied.

In the work digital x-ray apparatus on the basis of the gas-discharge linear detector is considered. X-ray images of laboratory rats are presented. Application prospects of gas-discharge detectors as a solution of the up-to-date radiographic problems are deduced.

Over the last decade there has been a significant increase in the number of patients with cancer worldwide. Although the new methods of cancer treatment are very effective, successful treatment is possible only with diagnosing the early stages of the disease. Therefore, creating new and harmless methods for early or pre-clinical diagnosis of cancer is an important task at present. The report describes the main issues and challenges related to development of microwave imaging systems of biological objects. The original hardware-software system for the study of biological objects was created. The system operates in the frequency range of 137.5 – 4400 MHz and has a sensitivity of 55 dB. The study and visualization of investigated object is performed according to the measurement scattering in the near field region. Solutions of salts and glucose were used as phantoms of biological objects. The fundamental possibility of detection and visualization of contrast areas of the internal environment as the gradients of the permittivity and conductivity is shown.

We succeeded in 3-D motion-picture imaging for dynamic motion of biological objects swimming at different depths by parallel phase-shifting digital holographic microscopy (PPSDHM). PPSDHM is a technique for high-quality instantaneous 3-D imaging of specimens in the microscopic field of view by single-shot recording of multiple phase-shifted holograms. We constructed a PPSDHM for recording high-speed dynamic phenomena and then motions of biological objects in water were recorded at 20 000 and 150 000 frames/s, respectively, which is the fastest among the previous reports on 3-D imaging of biological objects.

The imaging methods used at the ANKA Synchrotron Light Source (Institute for Synchrotron Radiation, Karlsruhe Institute of Technology) are briefly reviewed. Examples of recent applications of the phase-contrast imaging method using a grating interferometer and fast radiography with optic flow data analysis to study static and moving biological objects are presented.

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 issues of detecting the inhomogeneities are studied aimed at mapping the distribution of absorption and scattering in soft tissues. A modification of the method of diffuse optical tomography is proposed for detecting directly and determining the region of spatial localisation of such absorbing and scattering inhomogeneities as a cyst, a hematoma, a tumour, as well as for measuring the degree of oxygenation or deoxygenation of blood, in which the late arriving photons that diffuse through the scattering object are used.

A special probe with a 5-μm-diameter ball fixed at the end is developed for an atomic force microscope (AFM), with the use of which it is possible to obtain more correct values of the Young’s moduli of biological objects in liquid media and eliminate the risk of damaging the sample surface. In particular, the AFM measurements with this probe in situ revealed an increase in the Young’s modulus of rat blood vessel under the action of chlorhexidine.

Newly constructed 4th generation sources of intense synchrotron radiation in ultrafast pulses of only 10–50 fs and wavelengths up to X-rays, the free electron lasers, are expected to revolutionize development of biological science. To take full advantage of unique properties of the sources, new imaging techniques of molecular and microscopic biological objects are developed. Present article provides a short review of a stormy development of bioimaging with incoming soon 4th generation synchrotron radiation X-ray sources. Some implications for the future of new sources and techniques are discussed as well.

Acoustothermometrical measurements were carried out for the model biological objects. As model objects we used the plasticine bodies placed in the water. In the experiment the model objects were being heated up and cooled down. The temporal dependences of their acoustobrightness temperatures were obtained and the reconstruction of the 2-D temperature distribution was made. The position, size and temperature of the thermal source were detected. The reconstruction error was about 1{2mm for the position and size and about 1K for the temperature. These results were obtained when the measurement time was about 50s. As well we carried out the acoustothermometrical control during the laser hyperthemia of the mammary gland. The medicine procedure was continued 10min and the maximum gland acoustobrightness temperature was increased at about 7degrees.

In this article, the results of the experimental and theoretical developments for equipping the station “DICSI”, created on channel K1.3 (a) of the (Siberia-2) storage ring of the Kurchatov Centre for Synchrotron Radiation and Nanotechnology are considered. Argumentation for the basic parameters of the X-ray optical systems is given, photos and the schemes of created equipments are presented, in addition, the results of the test experiments with the biological objects are considered.

Photonic-crystal fibres with submicrometre waveguiding channels enhance nonlinear-optical processes, leading to unique regimes of nanoscale nonlinear-optical interactions. Here we provide an overview of the basic physical mechanisms behind the remarkable nonlinear-optical performance of micro- and nanochannel waveguides and discuss physically different scenarios of nonlinear-optical spectral and temporal transformations of ultrashort pulses in silica and multicomponent-glass photonic-crystal fibres, as well as in natural submicrometre waveguides encountered in biological objects. Small-size waveguides in photonic-crystal fibres with carefully optimized dispersion are used for the frequency shifting and shaping of ultrashort laser pulses, offering much promise for the creation of novel compact and convenient light sources for nonlinear spectroscopy.

In an optical tweezers system, the output signal of a photodiode quadrant detector and the temperature in a sample cell are two key factors for the quantitative measurements of mechanical properties of living biological objects such as cells, organelles and macro-molecules. In order to enhance the output of a quadrant detector and effectively control the temperature in a sample cell, the dependence of the temperature in the sample cell and the output of the quadrant detector for different illumination conditions are studied. The results show that appropriate illumination conditions can ensure both nearly constant temperatures in the cell and the desired output signal, which provides for the possibility of high precision and damage-free analysis of living biological objects.

The modification of biological objects (polysaccharides and cells) by CO2-laser radiation in water added drop by drop into the interaction region is studied theoretically and experimentally. Calculations are performed by using the models describing gas-dynamic and heterogeneous processes caused by absorption of laser radiation by water drops. It is found experimentally that the laser modification of polysaccharides leads to the formation of low-molecular derivatives with immunostimulating properties. A dose of the product of laser activation of the yeast culture Saccharamyces cerevisiae prevented the development of a toxic emphysema in mice and protected them against lethal grippe and also prevented a decrease of survival rate, increased the average life, and prevented the development of metabolic and immune disorders in mice exposed to sublethal gamma-radiation doses.

The methodological and technical aspects of the biological objects study by the time-resolved X-ray diffraction technique are described with reference to muscle contraction. The results of relevant investigations into the structural dynamics of a living muscle during its contraction are presented.

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.