This PDF file contains the front matter associated with SPIE Proceedings Volume 12192, including the Title Page, Copyright information, Table of Contents, and Conference Committee listings.

The mathematical model proposed for detection the function of size distribution of form for blood cells. Using the mathematical model we can theoretically calculate the size distribution function for particles of irregular shape with a variety forms and structures of inclusions that simulate blood cells in the case of in vivo and determine the degree of aggregation, for example, the platelet for case in vivo, which may indicate the presence of pathogenesis.

To assess changes in the level and localization of the proapoptotic proteins Pink1, Parkin, and Cofilin in rat dorsal root ganglia 24 hours after axotomy, we used the method of immunohistochemistry. To form an experimental model of axotomy, we dissected the rat sciatic nerve. As a control, we examined the ganglia of the intact nerve on the other side of the animal. It was demonstrated that in dorsal root ganglia, the proteins Pink1, Parkin, and Cofilin are localized in the cytoplasm of neurons. Their average level in the cytoplasm was significantly higher than the level in the nuclei. 24 hours after transection of the sciatic nerve, the mean level of Pink1, Parkin, and Cofilin proteins in the cytoplasm of neurons in the axotomized ganglion increased compared to the control. The Pink1/Parkin protein system is responsible for mitochondrial quality control. An increase in the expression of Pink1 and Parkin indicates that axotomy entails severe disturbances in the functioning of the mitochondrial network of neurons. Cofilin regulates the remodeling of the actin cytoskeleton by depolymerizing fibrillar actin during shape changes, cell movement, and endocytosis. Increased expression of Cofilin indicates that disruption of axon integrity triggers disassembly of actin filaments in the soma of neurons of dorsal root ganglia.

Using electron microscopy, we studied ultrastructural changes in neurons and glia cells of ganglia abdomibal 4 and 24 hours after transection of interganglionic connectives. Experiments on such model objects as ganglia of invertebrates provide information on the general biological mechanisms of the nervous system's reactions to mechanical damage. In the control samples, the bodies and nuclei of neurons had a rounded shape, the nuclear chromatin of neurons differed in the degree of condensation. The cytoplasm contained numerous Nissl bodies, the Golgi apparatus, located mainly in the perinuclear region, various elements of the cytoskeleton, ribosomes, elongated and rounded mitochondria with a moderately dense matrix and normal cristae filling the entire volume of mitochondria. Glial cells surrounded the bodies of neurons or unmyelinated axons of the neuropil and formed a multilayer sheath tightly attached to the neuron soma or axons. 4 hours after axotomy, disorganization of Nissl bodies and mitochondrial cristae was observed in the cytoplasm of neurons. 24 hours after the axotomy, ultrastructural changes in neurons intensified: compression of nuclei and compaction of nuclear chromatin were observed. There was a further disorganization of Nissl's substance, the appearance of voids and the loss of organelles. The internal structure of neuropil axons was completely destroyed. However, the ultrastructure of glial cells was found to be more preserved, and the presence of a certain amount of intact mitochondria in them indicated the continuation of synthetic processes in them. Some of the described ultrastructural changes in the ganglia of the abdominal nerve cord of crayfish indicate early stages of necrosis, but taking into account such changes as the contraction of nuclei and condensation of chromatin, these changes should be attributed to a mixed type of cell death.

Optical pacing (OP) has been proved to be a feasible noninvasive alternative to electrical pacing in recent years. IR lasers can be utilized for this purpose because of the absorption rate of infrared light, particularly wavelengths of 1450 nm, in biological tissue. As a result, the goal of this research is to look at the thermal effects of infrared radiation on cardiac pacemaker cells. To begin, we investigate the heat generation and temperature increases caused by IR pulses in biological tissues as a function of pulse length and radiant exposure depth. The toad heart is then treated with a pulsed infrared laser in an experiment (wavelength of 1450 nm). By measuring the toad's heart rhythm, the temperature effect of IR radiation on its cardiac pacemaker cells is examined. The findings reveal that the thermal effect of IR pulses can alter cardiac pacemaker cells based on variations in the T wave amplitude in the toad heart rhythm. In conclusion, this work shows that non-invasive IR pulses may successfully stimulate cardiac pacemaker cells.

Most radiological methods for examining the body, such as magnetic resonance therapy, radiography, ultrasound diagnostics, and many others demand the use of contrast agents. The existing contrast agents are imperfect and require further improvement. A special place among contrast agents is occupied by specific contrast agents, which allow targeted contrasting through the use of special ligands (for example, folic acid). In this work, we describe the preparation of stable gadolinium chelates with carbon nanostructures, which exhibit bright fluorescence and contain folic acid in their structure, available for binding to receptors. This opens up the possibility of using such structures for targeted contrast enhancement, as well as for local visualization of cancer cells and tissues.

Chronic hyperglycemia is the pathogenetic basis of the occurrence and development of macro- and microvascular disorders in diabetes mellitus (DM). The drug liraglutide is widely used to correct the glycemic profile in diabetic patients. The method of laser Doppler flowmetry (LDF) was used to study microcirculation disorders in rats caused by alloxan diabetes, as well as the state of the microvasculature against the background of hyperglycemia correction with liraglutide. Disturbance of microcirculation (MC) was manifested by a decrease in the perfusion index on the skin of the dorsum of the foot in combination with a decrease in the normalized amplitudes of endothelial and neurogenic fluctuations. In animals that underwent correction of hyperglycemia with liraglutide, stimulation of endotheliumdependent vasodilation and normalization of neurogenic vascular tone of the precapillary link were observed, which contributed to the restoration of impaired microcirculation of the hindpaw skin in rats with alloxan diabetes. Also, liraglutide caused a decrease in the concentration of markers of endothelial dysfunction (ED) in the blood serum and in the level of catecholamines (CA) relative to animals in the comparison group. Liraglutide contributed to the normalization of the serum concentration of vasculoendothelial growth factor (VEGF), the increased level of which indicated the inflammatory activation of endothelial cells.

Issues and solutions of data processing by Wiener's adaptive filtering and visualization in low-coherence interferometry system are described. Achieved speed for all steps of processing and visualization on different hardware is presented.

Medications with an antiseptic effect for the treatment of pain in the mouth and throat are especially relevant in the autumn-winter period. The composition of these drugs, in addition to the active substances with antiseptic action, also include auxiliary substances, for example, synthetic food colorants (SFC). The need to control the amount of SFC consumed is an important task, since exceeding the permissible daily intake can lead to allergic reactions, hyperactivity in children. Two chemometric methods applied were partial least squares (PLS) and principal component regression (PCR). These approaches were used to quantify the colorants in model colorants solutions and "Strepsils" lozenges aqueous solution based on information included in the visual absorption spectra. The calibration PLS and PCR models were evaluated by internal validation (prediction of compounds in its own designed training set of calibration) and by external validation over pharmaceutical preparation. The accuracy of the methods was evaluated through the root mean square error of prediction (RMSEP). The results of PLS and PCR methods were compared and the best models for the system were obtained with PCR. Ultimately, a method was developed for the chemometric-assisted spectrophotometric determination of E110 in the presence of E124 in the "Strepsils" tablets, which is characterized by simplicity and rapidity.

The paper presents the results of a study of conditionally healthy volunteers and patients with various maxillary sinuses diseases by digital diaphanoscopy with a comparison of the results obtained with CT studies. The results of the classification of pathological changes based on a quantitative assessment of the registered scattering patterns of light are also presented.

The comparative analysis of influence of low-intensity electromagnetic fields on the processes of self-assembly of core histones H2A and H2B was performed. To study the self-organization of histones H2A and H2B used the method of wedge dehydration. Image-facies analysis included their qualitative characteristics, as well as the calculation of quantitative indicators, followed by statistical analysis. It was established that electromagnetic radiation changes the self-organization of histones. At the same time, there is a differential sensitivity of histones to the influence of the red laser and UHF irradiation. Established fact influence of low-intensity electromagnetic fields on the process of self-assembly of core histones offers the prospect of further study of the biological effects of these types of radiation.

Various approaches to the characteristics of optical diffusion of the growing polymer foams as a specific version of the multiple scattering random media with a high level of disorder are considered. These approaches include the diffuse reflectance and transmittance measurements, low-coherence reference-based reflectometry, and full-field multi-speckle correlometry. The relationship between the key parameter of optical diffusion diagnostics, such as the transport mean free path of the probe light propagation in the foams and structural properties of polymer foams are discussed. A possible influence of the optical inversion effect under the wet-to-dry transition in expanding polymer foams on the diagnostic parameters is taken into account.

Biomechanics of eye tissues is an important parameter of the state of the ocular system and its study is of undoubted interest since there are several clinical situations in which an in vivo assessment of mechanical properties can help both in diagnosis and in treatment. The risk of developing glaucoma and keratoconus of the eye is associated with pathological changes in the biomechanical properties of such eye tissues as the cornea and sclera. Thus, the problem arises of studying tissue biomechanics and the possibility of influencing it. For this purpose, experiments were carried out to determine the dynamics of elastic properties of intact and modified tissue of the sclera and cornea of the pig’s eye by OCT elastography and speckle interferometry. Internal stresses found by numerical simulation from a comparison of subsequent OCT frames demonstrate a dependence on the biomechanics of the tissue sample. It was also shown that the time and temperature dependences of the contrast and correlation functions in speckle interferometry make it possible to track the onset of structural changes in the tissues during repetitively pulsed laser heating. A comparison was made in the behaviour of these curves for the central and peripheral regions of the cornea. The results obtained and their repeatability allow us to conclude that the speckle interferometry can be used as the basis for a system for monitoring structural changes in the cornea associated with the thermal effect of laser radiation. OCT elastography is a sensitive method for studying the biomechanical properties of eye tissues (cornea and sclera) under laser exposure, reflecting the dependence on the intraocular pressure of the eye. This method can be used as the basis for a control system in the development of medical technology for influencing the sclera and cornea of the eye.

The influence of organo-mineral fertilizer «Ekofus» on the growth, development and fluorescent parameters of ornamental plants Tagetes patula L. has been studied. It was found that the treatment of tagetes plants with ekofus accelerated the transition of plants to the flowering phase and increased the productivity of flowering, plant height, plant and root biomass. At the same time, no significant differences in the fluorescent parameters of plants in 3–4 weeks after treatment with ekofus were found in control and experimental plants, which indicates the absence of differences in the functional characteristics of the photosynthetic apparatus at late vegetation periods. Repeated spraying of tagetes plants during this period (in the phase of mass flowering) was also ineffective in terms of increasing photosynthetic activity.

The features of the structural and morphological characteristics of the powder of barium-containing tricalcium phosphate and coatings obtained by the method of thermal spraying on its basis have been investigated by the methods of optical and scanning electron microscopy. The optimal modes of plasma spraying of coatings on the basis of the studied powder, which make it possible to form a coating with a uniform and regular structure, have been established.

As is known, Spike surface glycoprotein (protein S) is present in all coronaviruses, including the novel SARS-CoV-2 virus causing a global pandemic in 2019. In the present day, the relevant gene S (encoding protein S) undergoes the most mutations compared with other SARS-CoV-2 genes. In the beginning of 2021, the newer variant of the SARS-CoV-2, the Delta variant B.1.617, was discovered in India. It is distinguished by the presence of a double mutation of the Spike protein. In this study, the protein S sequences have been transformed into the sequence of numbers to generate the genebased (GB-) speckles in order to identify the differences between the reference strain which was initially discovered in China, 2020 (GISAID: EPI_ISL_402124-S) and the new Delta strains which were recently found in either India (GISAID: EPI_ISL_254707; EPI_ISL_254707) or in the UK (GISAID:EPI_ISL_642476; EPI_ISL_255210). Differences in the relevant nucleotide sequences have been found and successfully characterized by means of virtual laser gene-based speckles (GB-speckles). In particularly, it has been demonstrated that implication of interference of two GB-speckles, generated on the virus nucleotide sequences, can be considered as a new direction in modern bioinformatics. It has been shown, that at the interference of two SARS–CoV-2 GB-speckle-patterns, two types of interference pictures are forming: quasi-random speckle structure without interference fringes or fringes, modulated by speckles.

The work investigated the effect of induction heat treatment (IHT) on the morphology of titanium coatings obtained by plasma spraying (PS). IHT of titanium samples was carried out at temperatures of 650±50 and 1200±50 °C and duration of 120 s. It was found that the porosity of the PS coating was 57±3 %. The average grain size was 9.57±0.2 μm, and the pore size was 13.01±0.5 μm. The thickness of the formed layers was 320±30 μm. Thermal modification at an inductor current of 2.6 kA led to an increase in the average grain size to 11.12±0.3 μm, the pore size remained practically unchanged and amounted to 12.40±0.4 μm, the surface porosity of the coating also did not change and remained equal to 58±5 %. The thickness of the modified layers decreased to 265±20 μm. With an increase in the inductor current to 8.0 kA, the average grain and pore size decreased to 8.95±0.2 and 8.12±0.2 μm, respectively. The porosity of the modified layer did not change and remained equal to 56±1%. After the modification process, the scale peeled off from the coating surface, which led to a decrease in the thickness to 197±25 μm. The study of adhesion strength by a qualitative method showed that this parameter increased after IHT.

In this paper, we report the synthesis of hydrophilic luminescent quantum dots (QDs) of the core/shell structure using two approaches: high-temperature organic synthesis of CdZnSeS/ZnS and aqueous synthesis of AgInS/ZnS. Dihydrolipoic and thioglycolic acids have been used as surface ligands to impart hydrophilic properties. The influence of whole blood and serum on the optical properties of both types of QDs was evaluated for their application in blood analysis. It has been shown that AgInS/ZnS QDs with emission in the red spectral region (λ_PL = 638 nm) remained the most stable in whole blood samples and its optimal dilutions (up to 1:100, inclusive). Whereas CdZnSeS/ZnS fluorescent in the green region of the spectrum (λ_PL = 530 nm) showed the best signal of fluorescence (PL) intensity in blood serum samples.

Advances in the development of ultra-compact semiconductor lasers have opened up new possibilities for the development of wearable devices implementing biophotonic technologies, such as laser Doppler flowmetry (LDF) and fluorescence spectroscopy (FS). This work is aimed to evaluate the correlation between diagnostic parameters simultaneously registered by a newly developed wearable device and a standard bedside fiber-based technique. Experimental studies with healthy volunteers using the occlusion test showed a high correlation between the parameters recorded by the two devices.

Optical characteristics of water in stratified lakes can be used to study the pigment composition of various groups of photosynthetic organisms, its depth distribution and changes in different seasons. In the Arctic zone it is especially important to explore the evolution of natural water bodies under the influence of climate change and urbanization processes. Several water bodies on the coast of the Kandalaksha Bay of the White Sea are known as being at different stage of isolation from the Sea. In some of them the colored water layers in their chemocline zone resulted from the massive development of anoxygenic phototrophic bacteria were observed. The most numerous inhabitants of the chemocline zone are green sulfur bacteria. Besides green sulfur bacteria and purple sulfur bacteria, there were found cyanobacteria above and inside the chemocline zone. To access the pigment concentration, we measured fluorescence spectra of acetone extractions prepared from water sampled from various depths within chemocline of the lake Trekhtzvetnoe in March 2021. To increase the sensitivity of fluorescence measurements to certain pigments we acquired synchronous spectra of luminescence spectrometer performing scanning with a constant wavelength offset of 30 nm. This paper presents for the first time depth distribution of photosynthetic pigments BChl d (from green sulfur bacteria) accompanied with phycobilins (from cyanobacteria) derived from synchronous fluorescence spectra of acetone extractions prepared from water from various depths. This type of spectral measurements allowed us to receive depth distribution of cyanobacteria within the bacterial plate of green sulfur bacteria with very high depth resolution.

The nucleotide sequences of the GPCR gene of Lumpy Skin Disease Virus (LSDV) and Sheeppox Virus (SPPV) strains have been transformed into 2D realizations of GB-speckles (Gene-Based speckles). Based on the analysis of statistical properties of corresponding GB-speckles, a possibility of differentiation between wild field LSDV and the SPPV strains which could be used as heterologous vaccines against Lumpy Skin Disease has been shown. It has been demonstrated that an application of the GB-speckles has the great perspectives from viewpoint of modern bioinformatics.

In this study, the GB-speckles were used to study the probable precursor for L. monocytogenes ST734 strains, which were detected twice in the world, namely: for the first time in Chile in 2009 and, recently, in 2019 in the Republic of Serbia. We found that these strains belong to the clonal complex I and differ fromL. monocytogenes ST1 strains by a single nucleotide change in the gene dat. This is the first report demonstrating the using GB-speckle-structures to detect evolutionary genetic changes in L. monocytogenes strains.

Light-sheet microscopy (LSM) is an imaging technique that has the facilities of fast and high contrast 3D imaging with minimal light exposure. In LSM, a conventional Gaussian beam has a rapid divergence so it prevents the generation of a uniformly thin sheet of light. An Airy beam remains diffraction-free over long distances compared to the Gaussian beam and also shows up an advantage of a self-healing property. Herein, beam shaping is widely noticeable to generate different types of beams and to modify their properties. The Airy beam could be combined with light-sheet microscopy to achieve a higher contrast over an extended field of view (FOV) and penetration depth. In this research, we investigate the effect of the Airy beam profile on the LSM properties including the light penetration depth and the image contrast. The beam properties are controlled by computer-generated hologram (CGH) patterns on a spatial light modulator (SLM).

This article describes the developed method for classifying the type of migraine in patients. For this, we analyzed the individual characteristics of patients with different types of migraine when performing cognitive tests. Evoked potentials were used for the analysis when observing the visual stimulus and solving the cognitive test. The cognitive test had different levels of complexity, which made it possible to consider separately the evoked potentials received in solving cognitive tasks of high complexity and separately with a small complexity of the cognitive task. These cases were compared with the case when the evoked potentials were built for all available cognitive tasks. The analysis of the emerging individual characteristics made it possible to determine the trends in the observed evoked potentials in different types of migraine, which makes it possible to more effectively monitor the condition of patients suffering from migraine during treatment.

In this report, we proposed a method for identifying individual characteristics in electroencephalography of the brain of people suffering from chronic migraine during cognitive load. The method is based on a recurrence analysis. The analysis was carried out separately for complex and simple stimuli during cognitive test and comparisons were made between them. This approach makes it possible to identify for each subject the connections between records in which the frequency increases at the time of the cognitive test and/or a stable pattern is formed. The proposed method has a large number of applications in medicine and neurophysiology.

Radiotherapy is one of the well-established and effective methods for many cancer treatments especially for brain tumors. Despite remarkable advancements, the dose tolerances of normal tissues continue being the main limitation in radiotherapy. Consequently, there is a high unmet medical need to develop predictive biomarkers, and particularly noninvasive real-time methods to establish the radiotherapy effect during the treatment, as well as to optimize radiotherapy dose planning to avoid severe short and long-term toxicities. Optical techniques are well suited for in vivo clinical tissue imaging as they are non-ionizing and can be label-free. In particular, near-infrared (NIR) spectroscopy technology is easy to exploit in online monitoring clinical treatments in demanding clinical environments. In this paper, we study its potential to utilize it in radiotherapy for measuring immediate effects of irradiation on skin tissue. Skin is sensitive to acute side effects of irradiation in radiotherapy and to reduce these unwanted effects is of high interest. We used diffuse reflectance spectroscopy, at spectral range of 650 nm – 1100 nm, and continuously measured human skin in radiotherapy before, during and after irradiation, and compared the response with ex vivo chicken sample measurements. In our results we show that irradiation causes dynamical changes in the detected NIR light when measured in vivo from human skin. These spectral responses could be potentially exploited in development of methods to perceive skin toxicity risks in radiotherapy.

The interaction of laser radiation of wavelengths of direct optical generation of singlet oxygen with cell culture media was simulated. Using the COMSOL Multiphysics software, the distribution of the thermal field over the culture media volume was obtained depending on the wavelength, power and exposure time. The results demonstrate the importance of taking temperature into account when conducting experimental studies at the cellular and organismal levels.

Near-infrared spectroscopy (NIRS) based techniques in brain monitoring utilize the spectrum range approximately between 650 nm and 950 nm, where light attenuation is low enough to enable reaching the cerebral cortex of the brain. In these studies, particularly oxygenation changes in the cerebral cortex are of great interest since the concentrations of oxyhemoglobin (HbO) and deoxyhemoglobin (HbR) change due to coupling of hemodynamics to cortical neural activity. There are numerous simulation and phantom studies that show near-infrared (NIR) light can penetrate in the human head to a depth of approximately 1–2 cm, reaching the brain cortex. However, NIR propagation and light attenuation is also dependent on anatomy and size of the subject’s head. This related, we studied experimentally the effect of layer thicknesses of dura and cerebrospinal fluid (CSF), skull and skin to detected light intensity when measured in vivo from human heads with different layer thicknesses. We studied anatomy of 15 human heads in magnetic resonance imaging (MRI), particularly the thickness and morphology of the tissue layers of CSF, skull and skin. At the same time, we measured intensity and absorbance spectrum, at range of 600 nm to 1100 nm, from the forehead of these subjects when fibre detector was placed at distances of 1 cm and 3 cm from the fibre source. Our results show that each layer affects the detected NIR spectrum when layer thickness changes, particularly at 3 cm source-detector distance. However, these small spectral variations, caused by changes head anatomy, most likely do not have significant influence in quantifying cerebral hemodynamics.

A modern trend in the development of optical non-invasive diagnostics (OND), which makes it possible to reduce the number of disadvantages in individual applications of methods, is a multimodal approach when one diagnostic technology combines various optical and other physical research methods, which makes it possible to provide early diagnosis of functional changes before clinical manifestations of the disease based on the measurement results. In the last decade, there has been a steady increase in interest in the problems of non-invasive research of microcirculatory tissue systems (MTS) of the human body, which is due to their significant role in the pathogenesis of various diseases. For a wider introduction of OND technologies into clinical practice, it is necessary to further improve the methodology of the multimodal approach in the development of new methods and technical means for assessing the functional state of MTS in various fields of medicine.

This article presents a liquid phantom technology that simulates the fluorescent properties of protoporphyrin IX (PPIX). A technology was developed for the isolation of PPIX from dark egg shells with a final concentration close to the real values in human tissues. A comparative analysis of the transmittance coefficient of the manufactured phantom as well as the fluorescence spectra measured through the combined use of a CCD spectrometer and a hyperspectral camera is presented as results.

The possibility of using the laser Doppler flowmetry (LDF) method for the diagnosis of masked hypertension is considered. Significant trends in changes in parameters between groups of volunteers were identified. This indicates the possibility of using the LDF method to make decisions about the further follow-up of patients for the presence of a hidden increase in BP.

The article is devoted to the analysis of skin perfusion oscillation processes with wild-type and synuclein-deficient mice with three knockout (KO) types: αγ-KO, β-KO, and αβγ-KO. The role of synucleins in tissues that exclude the central nervous system remains sparsely studied. Laser Doppler flowmetry was used to investigate the potential involvement of synucleins in murine microcirculation functioning This method is widely used to analyze microcirculatory disturbances in a variety of pathologies and has proven to be sensitive to the manifestation of abnormalities of normal function. The study revealed that deficiency of β-synuclein affects oscillation processes more than αγ-synuclein deficiency.

Currently, there is an increased interest in aluminosilicates of natural origin, both in connection with the use in detoxification of waters and soils, and as a matrix for the creation of biologically active composites. The morphological characteristics of glauconite grains from the Beloozersk deposit in the Saratov region and its composite have been studied by scanning electron microscopy. The main sorption characteristics of the enriched fraction of glauconite in relation to chlorhexidine digluconate were determined by spectrophotometry. On the basis of the presented sorption isotherm, the mechanism of immobilization of chlorhexidine ions on a glauconite matrix is analyzed in accordance with the provisions of Langmuir's theory. The basic constants of the Langmuir equation are determined. It was revealed that glauconite has a high sorption activity (up to 87%) in relation to chlorhexidine, which can be in demand as filter media in wastewater treatment, in agriculture, as well as in medicine and veterinary medicine, to create new types of enterosorbents with antibacterial properties.

The effect of sympathetic activation of sweat glands on the spatio-temporal distribution of skin temperature was studied. The practical significance of the study of sweat glands is supported by the fact that each sweat gland is controlled by the sympathetic cholinergic nerve. Dysfunction of the sympathetic nerve leads to inhibition of the activity of the sweat glands and accompanies many common diseases. In this study, the statistical and spectral properties of the dynamic infrared thermogram of skin with eccrine sweat glands during deep inspiratory gasp (breath test) were investigated. The number of open sweat pores was used as a ground truth measure for the activity of the sweat glands. Results: We found that the activation of the sweat glands, which characterizes the enhancement of the sympathetic response, leads to a change in the statistical spatial distribution of temperatures on the surface of the human body. The histogram of temperature showed a shift to the low-temperature region with a simultaneous increase in the standard deviation. The possibility of using the standard deviation and the skewness (asymmetry of the histogram) to assess the dynamics of the activity of sweat glands was shown. For the first time, the Statistical Pore Activation Index (SPAI) was introduced, which is more adaptive and shows greater accuracy than skewness. The activity of the sweat glands resulted in the appearance of spectral components within the region near 0.1 Hz, which is not typical for oscillations in skin temperature caused by hemodynamics. The results can be used for spectral separation of thermographic data from components caused by hemodynamics and activity of the sweat glands (vasomotor and sudomotor activities). Filtering the dynamic thermograms based on the investigated spectral and statistical features might serve as a method of mathematical processing for mapping the sweat glands and blood vessels on the skin surface. This might be used as a new diagnostic tool in the field of physiology and medicine.

For photodynamic therapy (PDT), galactose – Lutetium (Lu)-phthalocyanine, as a novel photosensitizer, was administered by intratumoral injection in 8 outbred albino male mice with inoculated hepatoma in a dose of 2 mg/kg. Then, tumors were irradiated through the skin by 670 nm-diode laser source with irradiation dose 200 J /cm2 applied for 1000 sec. The withdrawal of the animals from the experiment and sampling of tissues for morphological study were performed before (n=4) and 72 hrs after PDT (n=4). Tissue of the tumor was taken for morphological examination and fixed in 10% formalin. Serial paraffin sections were stained with hematoxylin-eosin and with the use of immunohistochemical staining with antibodies to proliferation marker Ki-67 and apoptotic marker BAX (Abcam, UK). 3 days after PDT with galactose- Lu-phthalocyanine, pronounced necrotic changes and inflammation reaction were observed in central tumor area, necrosis fields occupied up to 80% of the area. The dystrophic changes, reduction of proliferation degree and development of apoptosis in tumor cells were observed on tumor periphery. The decreased expression of proliferation marker Ki-67 and the increased expression of apoptotic marker BAX were noted in tumor cells after PDT.

For potential use as a diagnostic test, morphological changes in the lung tissue of rats after inhalationof e-cigarette liquid based on polypropylene glycol and glycerol were studied ex vivo and in vivo. Lungs of Wistar rats placed for 1 hour in ecigarette liquid were used in the ex vivo study. The in vivo study was performed on 12 mature male Wistar rats. The animals were divided into two groups - experimental and control, 6 rats in each. Rats of the experimental group were placed in aerosol administration chamber and exposed to an aerosol of nicotine-free liquid for electronic cigarettes. Rats of the control group were intact. The animals were removed from the experiment one hour after inhalation, lung tissue samples were examined ex vivo using optical coherence tomography (OCT) and lung tissue spectroscopy. After manipulations, lung samples were fixed in 10% formalin solution and embedded in paraffin. Then histological sections were made according to the conventional methods, followed by hematoxylin and eosin staining. Comparative analysis of B-scans ex vivo of lung tissue samples placed in e-cigarette liquid and control samples showed the presence of a luminescent effect on lung tissue in the studied solution, as alveoli are filled with the solution and scattering is reduced. The structure of the tissue differs from the control samples. B-scan in vivo studies are characterized by the presence of voids of rather large size. Histological examination of ex vivo and in vivo specimens noted morphological changes in lung tissue structure corresponding to the changes observed in OCT.

Optical properties of the porcine gingival mucosa under the influence of smoking vapes (mixtures of propylene glycol, glycerol, and water) using diffuse transmission and reflection spectroscopies were studied in a wide spectral range from UV to NIR. The principle of diffuse spectroscopy is based on the ability of tissue biological molecular chromophores (hemoglobin, oxyhemoglobin, collagen, DNA, etc.) to absorb diffusely scattered light of a certain wavelength. Scattering is a key feature in light transport and attenuation in tissues, especially in UV. Thus immersion optical clearing provided my tissue impregnation with smoking liquids may have a great impact on tissue optical properties. In this study, for the porcine gingival mucosa, the specific features of tissue optics with the formation of three dynamic optical windows in the UV were revealed. By combining the immersion technique with UV-spectroscopy, it was possible to verify and study the major optical clearing mechanisms - tissue dehydration and refractive index matching, and to discover that the optical clearing efficiency is much higher in the deep-UV than in the visible-NIR range. These results prove that the refractive index mismatch in tissues is strong in the UV wavelength range, which causes a strong light scattering. Suppression of light scattering of the oral mucosa at the application of smoking liquid can be included in clinical protocols for personalized treatment of dental diseases using phototherapy, physiotherapy, photodynamic therapy, laser treatment, and optical diagnostics. Fortunately, e-cigarette smoking vapes are certified by medical agencies around the world for human use.

The knowledge of the optical properties of biological tissues in a wide spectral range is highly important for the development of noninvasive diagnostic or treatment procedures. The dispersion coefficient is one of those properties, from which various information about tissue components can be retrieved. This study is focused on the measurements of the refractive index of ex vivo cow brain gray matter samples in the visible/near-infrared (NIR) spectral range at room temperature for characteristic laser wavelengths: 480, 486, 546, 589, 644, 656, 680, 800, 930, 1100, 1300, and 1550 nm. Measurements were performed using the multiwavelength Abbe refractometer. Cow brain gray matter samples of 0.5 mm thick obtained from ex vivo cow brain were investigated. The specific increment of the refractive index depending on the temperature of the samples and the Sellmeier coefficients was calculated. The experimental results allowed us to calculate the cow brain gray matter dispersion with the Cauchy, Conrady, and Cornu equations. It was observed that all those equations provided good data fitting in the spectral range of the measurements, but differences were observed outside these limits. We validated the proposed method using distilled water and the cow brain gray matter ex vivo, and the experimental results were consistent with the reference data.