Biological Objects Research Articles

Influence of Electromagnetic Waves on the Temperature Field of Frozen Biological Objects in Arctic Conditions

Influence of Electromagnetic Waves on the Temperature Field of Frozen Biological Objects in Arctic Conditions

A neutron source for the study of biological objects formed from superficially touching cones made of borated spheroplastics

At the Prometheus medical accelerator with a proton beam energy of 225 MeV, a source of fast and epithermal neutrons was constructed and measurements of neutron dose profiles at the output of the neutron channel were carried out using the BDMN-100 detector. A heavy NaI target was used to produce fast neutrons. Together with the research laboratory of the Central Laboratory of Avangard JSC, a new protective material against neutrons called wikineutron was developed, with a different percentage of 10B. This new material has been studied many times at the Prometheus proton accelerator and the Pakhra electron accelerator. Based on the developed new protective materials against neutrons, a shadow protection was formed, made in the form of surface contacting cones, forming a channel of fast and epithermal neutrons. Fast neutrons can be used for remote therapy. Also, a neutron beam can be used to study biological objects and cells. It is also possible to use a neutron source from the Prometheus accelerator for the treatment of superficial tumors. The developed neutron channel can be used for medical work on the creation of new radiopharmaceuticals containing boron and other highly absorbing elements. The developed neutron source is a compact low-power source of therapeutic neutrons, which can be used for the treatment of superficial types of cancer. The main goal of the work was: the formation, based on the developed neutron-absorbing materials, of a neutron channel, which has a simple design and can be used for boron-neutron capture therapy and nadepithermal therapy; creation on the neutron channel of a beam of epithermal neutrons and supra-epithermal neutrons to assess the effectiveness of the use of radiopharmaceuticals.The developed neutron-absorbing materials made it possible to create a neutron channel of epithermal neutrons and supra-epithermal neutrons for therapy and the development of gold-based radiosensitizers.

Postmortem tissue changes and dynamics of their impedance parameters: a preclinical experimental study

Background. Establishing regularities in postmortem intervals comprises one of the main tasks of the forensic science of death and cadaveric phenomena. The knowledge of these regularities is directly related to reconstructing the postmortem conditions and, consequently, to determining the postmortem interval. Objective. To analyze postmortem changes in cadaver tissues and dynamics of their impedance parameters under the conditions of natural biocenosis. Methods. The study involved the cadavers of model biological objects – eight pigs, aged one to two months, weighing up to 10 kg. Experimental studies of cadaver decomposition were carried out under natural biocenosis conditions, daily for 28 days with two replications. Changes in cadaver tissues during decomposition were recorded and analyzed. The subject of biophysical studies was the tissue impedance parameters of three diagnostic zones of the biological object: the musculocutaneous flap, the cartilaginous part of the third rib and the calcaneal tendon. Impedance measurements for each postmortem interval were performed at five studied current frequencies: 100 and 120 Hz, 1, 10 and 100 kHz. A total of 2,400 readings were taken. Statistical analysis of the study results was carried out by means of Statistica 8.0 (StatSoft Inc., USA). Results. Postmortem biological changes in cadaver tissues correlate with the nature of their impedance dynamics. The study of impedance under conditions of natural biocenosis established its identical dependence on the postmortem interval for all current frequencies of the study of all diagnostic zones of model biological objects: in the initial interval of 0–4 days, the impedance gives a “surge” followed by a smoother decrease. Cadaver tissues were recorded to indicate the presence of impedance dispersion in general in the studied frequency range and the absence of dispersion directly for high frequencies. Conclusion. Understanding the causes and essence of postmortem processes contributes to assessing and substantiating changes in any characteristics of tissues measured quantitatively, including impedance indicators, as well as to predicting the prospects of their use for specific practical purposes, in particular, for determining the postmortem interval.

Use of Polyethylene Waste Contaminated with Oil Products in the Production of Asphalt Cement Concrete

It was shown that high-density polyethylene (HDPE) contaminated with engine oil is effective as a reinforcing and modifying element in the asphalt cement concrete composition. It was found that shredded packaging materials with engine oil contamination in the amount of up to 17.5 % can be successfully used as raw materials in the production of asphalt-cement concrete mixtures. It was proven that the use of HDPE with bitumen increasesthe heat resistance of the mixture due to the formation of new physical and chemical bonds between them. It was demonstrated that the inclusion of of oil-contaminated container waste in the asphalt cement concrete has no adverse effect on living biological objects.

Радиоэкологическая обстановка в районе вводимого в эксплуатацию рудника № 6 пао «Приаргунское горно-химическое производственное объединение»

Purpose: Study of the radioecological situation around mine No. 6 of PJSC ‘Priargunsky Industrial Mining and Chemical Association’ named after E.P. Slavskiy" before commissioning. Material and Methods: During the radiation survey, to measure the ambient dose equivalent rate, the pedestrian gamma survey method was used using the portable spectrometric complex MKS-01A ‘Multirad-M’ (Russia) and the dosimeter-radiometer MKS-AT6101s (Belarus). To study the specific activity of radionuclides in the soil, samples were taken in accordance with GOST 17.4.3.01-2017. The activity of gamma-emitting radionuclides was measured on a stationary gamma spectrometer manufactured by Canberra (USA). The activity of 210Po and 210Pb was measured on the radiometric system UMF-2000 (Russia) after their radiochemical extraction from samples. Dose assessment of exposure to biological objects was made using dose coefficients established in ICRP Publication 136, considering recommendations R52.18.820-2015. Results: The results of the study showed that the ambient dose equivalent rate of gamma radiation varied in a wide range from 0.1 to 4.9 µSv/h. The average value in the background areas is 0.14±0.02 µSv/h. The specific activity of natural radionuclides outside the rock dumps, except for 40K, in some areas exceeds the background values up to 10 times. The ecological risk for the considered terrestrial biological objects (grass, shrub, soil worm and mouse-like rodents) does not exceed 10‒2. Conclusion: There are areas on the territory with traces of anthropogenic activity, which led to man-made radiation contamination. The highest levels of ambient dose equivalent of gamma radiation occur near rock dumps. The rest of the territory has local areas with radioactive contamination. Doses of exposure to biological objects don’t have a significant effect on the incidence, reproduction, and life expectancy of terrestrial biological objects.

Интеграция моделей oir мкрз в дозиметрическую систему idose 2

Introduction: The iDose 2 dosimetry system is a tool for assessing the doses of internal irradiation of workers under the current individual dosimetry control (IDC). In this system, according to a series of measurements of the activity of radionuclides in biological objects (including those not exceeding the detection limit of the measurement technique) and information on contact times and types of compounds, estimates of the committed effective dose equivalent (CEDE) of internal irradiation, as well as their uncertainties, are made based on the Bayesian approach. It is possible to integrate practically any biokinetic models of the behavior of radionuclides in the human body, presented in the form of a system of ordinary differential equations (ODEs) with constant transition coefficients between compartments, into the iDose 2 dosimetry system without changing the source code. Purpose: Integration of new combined biokinetic models for the list of radionuclides: H-3, Sr-90, Cs-137, Pu-238, Pu-239 and Am-241 from Publications 100, 130, 134, 137 and 141 of the ICRP (conventionally called the series Occupational Intakes of Radionuclides (OIR)), for ingestion and inhalation routes of intake with AMAD = 1 and 5 microns. Material and methods: For each variant of the biokinetic model, the functions of retention/removal of radionuclides were found through the eigenvectors and eigenvalues of the matrix describing the ODE system. Results: A total of 65 new biokinetic models and 180 functions of radionuclide retention/removal in the form of a sum of exponents were integrated and quality control was carried out.

Modeling Biological Face Recognition with Deep Convolutional Neural Networks.

Deep convolutional neural networks (DCNNs) have become the state-of-the-art computational models of biological object recognition. Their remarkable success has helped vision science break new ground, and recent efforts have started to transfer this achievement to research on biological face recognition. In this regard, face detection can be investigated by comparing face-selective biological neurons and brain areas to artificial neurons and model layers. Similarly, face identification can be examined by comparing in vivo and in silico multidimensional "face spaces." In this review, we summarize the first studies that use DCNNs to model biological face recognition. On the basis of a broad spectrum of behavioral and computational evidence, we conclude that DCNNs are useful models that closely resemble the general hierarchical organization of face recognition in the ventral visual pathway and the core face network. In two exemplary spotlights, we emphasize the unique scientific contributions of these models. First, studies on face detection in DCNNs indicate that elementary face selectivity emerges automatically through feedforward processing even in the absence of visual experience. Second, studies on face identification in DCNNs suggest that identity-specific experience and generative mechanisms facilitate this particular challenge. Taken together, as this novel modeling approach enables close control of predisposition (i.e., architecture) and experience (i.e., training data), it may be suited to inform long-standing debates on the substrates of biological face recognition.

Характеристика модели асцитной карциномы Эрлиха и перспективы ее применения в экспериментальной фармакологии ветеринарных препаратов

The article provides an overview of the most significant works of domestic and foreign authors devoted to the Ehrlich ascites carcinoma biological model. The analysis of the available literary sources showed that despite the long history of the existence of this model and its application in biomedical research, it has not yet become widespread in veterinary medicine. It should be noted that the Ehrlich ascites carcinoma model has a number of peculiarities that allow it to be used for the needs of veterinary medicine, in particular, experimental pharmacology at the stage of drug design and its preclinical testing. The high resistance of malignant cells and tumor survival in experimental animals, as well as the ease of its cultivation and relatively rapid tumor growth, make this model a convenient biological object for research. The effect of tumor cells on the body of the animal with a tumor leads to a change in a number of biochemical indicators of various tissues and organs, and a general toxic effect. In this case, an imbalance of the free-radical and antioxidant systems is observed, the body is exposed to oxidative stress. The immune system under the effect of Ehrlich ascites carcinoma also undergoes a number of changes. Thus, in response to the development of tumor-induced pathological processes, recruitment of immunocompetent cells and an antitumor immune response are observed, which at the same time is suppressed as carcinoma cells grow under the action of immunosuppressive physiologically active compounds produced by the tumor, escape of tumor cells from immunological surveillance and remodelling of immune cells in the tumor microenvironment. These processes lead to suppression of the immune system and as a result to the death of animals. These peculiarities make it possible to use the Ehrlich transplantable ascites carcinoma model for testing new veterinary drugs with potential antiblastoma, immunomodulatory, antitoxic properties, as well as medicinal formulations for restoring biochemical indicators and redox homeostasis under conditions of tumor-induced immunosuppression and chronic inflammatory process, and also to study the mechanisms of cell adaptation, including the immune system, under the action of carcinogenesis factors.

Muc2-дефицитные мыши как модель хронического воспаления

The article provides an overview of the most significant works of domestic and foreign authors devoted to the Ehrlich ascites carcinoma biological model. The analysis of the available literary sources showed that despite the long history of the existence of this model and its application in biomedical research, it has not yet become widespread in veterinary medicine. It should be noted that the Ehrlich ascites carcinoma model has a number of peculiarities that allow it to be used for the needs of veterinary medicine, in particular, experimental pharmacology at the stage of drug design and its preclinical testing. The high resistance of malignant cells and tumor survival in experimental animals, as well as the ease of its cultivation and relatively rapid tumor growth, make this model a convenient biological object for research. The effect of tumor cells on the body of the animal with a tumor leads to a change in a number of biochemical indicators of various tissues and organs, and a general toxic effect. In this case, an imbalance of the free-radical and antioxidant systems is observed, the body is exposed to oxidative stress. The immune system under the effect of Ehrlich ascites carcinoma also undergoes a number of changes. Thus, in response to the development of tumor-induced pathological processes, recruitment of immunocompetent cells and an antitumor immune response are observed, which at the same time is suppressed as carcinoma cells grow under the action of immunosuppressive physiologically active compounds produced by the tumor, escape of tumor cells from immunological surveillance and remodelling of immune cells in the tumor microenvironment. These processes lead to suppression of the immune system and as a result to the death of animals. These peculiarities make it possible to use the Ehrlich transplantable ascites carcinoma model for testing new veterinary drugs with potential antiblastoma, immunomodulatory, antitoxic properties, as well as medicinal formulations for restoring biochemical indicators and redox homeostasis under conditions of tumor-induced immunosuppression and chronic inflammatory process, and also to study the mechanisms of cell adaptation, including the immune system, under the action of carcinogenesis factors.

Results of Photobiological Studies on Growing Lettuce under Multispectral Radiation Sources

Introduction. When growing plantations through using vertical farm technology, an important factor for regulating energy processes is electromagnetic radiation of irradiators with certain optical wavelengths. Aim of the Article. The aim of the study was to substantiate the technology of application of LED radiation for growing green crops in vegetation facilities under conditions of multispectral radiation by determining the patterns of changes in the qualitative indicators of lettuce varieties Cook, Chrysolite and Afitsion and to create the concept of LED irradiators for controllable crop production. Materials and Methods. The experiment was conducted in the vegetation facility, in three chambers of which different radiation (in spectrum) of biological objects (green plants) was created using irradiators of different spectrum, other things being equal. Results. Experimental studies have determined a range of diverse reactions to radiation of a certain spectral composition. Stable increase in the content of threonine, phenylalanine, valine, serine, alanine and sugars was found in lettuce variety Cook grown under the irradiator with adjustable spectrum. At the same time, a stable decrease in the content of these substances was observed in lettuce variety Chrysolite grown under the irradiator with controlled spectrum. For vitamin C content, the reaction was the opposite: a decrease in vitamin C content in lettuce variety Cook and an increase in vitamin C content in lettuce variety Chrysolite grown in a spectrum-controlled irradiator. For lettuce variety Afitsion, the response to the content of the test substances was dissimilar in both experiments. Discussion and Conclusion. The development and application of LED irradiators with fine turning for controlled crop production should be based on photobiological studies, taking into account specific responses of plantation varieties. For these purposes, there is proposed a technical solution with a set of LEDs controlled by individual channels using digital technologies.

Luminescent Media Based on Heteroligand Lanthanide Complexes and Lyotropic Mesophases for Bioimaging Application

New terbium and europium heteroligand complexes with substituted 1,2,3-triazole – bis-1,3-(4-methylcarboxyl-1,2,3-triazol-1-yl)xylylene have been synthesized. A study of luminescent properties showed that the complexes exhibit high optical characteristics. The luminescence efficiency of [Tb(AcAc)2(TR)(H2O)2], increases by 13 % compared to the monoligand complex [Tb(AcAc)3(H2O)2]. In order to create biocompatible systems, an approach for the solubilization of hydrophobic complexes by incorporating them into the lyomesophase structure of P123/DMSO has been developed. According to polarization optical microscopy, the hybrid system containing 0.2 % of the [Tb(AcAc)3(H2O)2] complex shows a lamellar mesophase. Fluorescence microscopy study showed that the [Eu(TTA)2(TR)(H2O)2] complex is efficiently adsorbed on the surface of the Paramecium caudatum microorganism and exhibits red luminescence allowing visualization of biological objects.

Применение нейронных сетей для классификации объектов в видеоданных в задачах автоматического мониторинга состояния биологических объектов

A steady trend towards the development of technologies in everyday life and industry leads to their constant complication, to the introduction of new developments and methods, new ways of acquiring and processing information. Video surveillance systems have become an integral part of everyday life. Cameras are installed in apartment buildings, public places, even in apartments and private houses. However, one of the most important areas where computer vision has found significant application is the observation of biological objects and analysis of their behavior and state, especially in the context of nature protection and automation of animal behavior research. With the growth of quality and quantity of video materials, the problem of accurate and efficient methods for classifying objects in real time becomes relevant, especially when it comes to automatic monitoring of animal condition. There can be no mistakes here, so it is necessary to use only the latest technology. This paper describes the main types of object recognition, considers popular modern neural network architectures, and performs a comparative analysis of some of them in relation to the problem to be solved. In the course of work using methods of additional processing and image annotators SuperVisely and VGG Image Annotator, a dataset with more than a thousand unique images for extraction of relevant characteristics of objects was formed, and experimental studies of the quality of object recognition on video using pre-trained known neural network models were carried out. The requirements to the initial data for effective solution of the problem of automatic monitoring and prediction of the condition of biological objects have been defined and formulated. It is shown that in order to avoid the appearance of blind zones in the animal habitat it is necessary to use a sufficiently large number of cameras placed with overlapping of the investigated space so that the monitoring objects were constantly in the field of visibility. This will subsequently make it possible to compile an overall high-resolution picture made up of images from all cameras and on the basis of the obtained picture to classify objects using artificial neural networks.

Model of Electrical Stimulation of Back Muscles in the Treatment of Scoliosis

The article presents a three-dimensional model of the tissues of the human back in the ZBrush and SolidWorks software packages. Modeling of the spinal column with a bend, muscles, adipose tissue and skin was performed. Using the COMSOL Multiphysics environment, the effects of electrical stimulation on biological objects are modeled, and characteristics are determined. When modeling, in the properties of each biological tissue, the values of electrical conductivity and relative permittivity were set, the electrodes were adjusted, a grid was created to divide the models into smaller parts and elements, and the required frequency was adjusted. To verify the simulation results, a study was carried out on the patient, the calculation and analysis of the results obtained. The developed models can be used in clinical medicine to determine the strength of the stimulating current and set the parameters of electrical stimulation. When building a model, one can change the thickness of adipose tissue, skin, muscle and bone sizes, change the size of the electrodes, and thereby select the most optimal parameters for electrical stimulation. Models can be used in the development of the most effective method of electrical stimulation and the scheme for applying electrodes for a certain type of scoliosis.

Potential of Multifractal Analysis for Characterizing Movements of Biological Objects

Potential of Multifractal Analysis for Characterizing Movements of Biological Objects

Determination of reference intervals for atomic force microscopy parameters characterizing erythrocyte size

Introduction. Atomic force microscopy (AFM) is the cutting-edge method for imaging of cells and subcellular structures, and it has wide application prospects in the laboratory diagnostics. For AFM effective using in practical medicine, it is necessary to determine the reference intervals (RI) for biological objects, particularly for erythrocytes (red blood cells). Aim.To determine the RI for AFM parameters characterizing erythrocyte size in healthy subjects. Materials and Methods. 32 blood donors aged 18–60 (22 males, 10 females) were enrolled into the study. All the participants have undergone light microscopy of a whole blood smear, clinical blood test, determination of the serum ferritin level, and AFM imaging of erythrocytes. Statistical analysis was done with SPSS, and parametrical criteria were used. RI were calculated according to the GOST (Russian State Standard) R 53022.3-2008. Results and Discussion. In all the participants, both all the parameters of clinical blood test and the ferritin serum level, were within their RI. According to light microscopy, in all the participants, erythrocytes were normocytes with unchanged form. So, investigated subjects showed their applicability to be used as the reference group for the determination of RI for AFM parameters characterizing erythrocyte size. We calculated RI and their confidential intervals for the following size parameters: minimal and maximal normocyte height, minimal and maximal normocyte diameter. Conclusion. Our results contribute to the development of AFM clinical methodology. Our results confirm the advisability of further investigations dedicated to the RI determination for AFM parameters characterizing erythrocyte size in increased samples of healthy subjects of different age groups.

Conductive Polymers and Their Nanocomposites: Application Features in Biosensors and Biofuel Cells.

Conductive polymers and their composites are excellent materials for coupling biological materials and electrodes in bioelectrochemical systems. It is assumed that their relevance and introduction to the field of bioelectrochemical devices will only grow due to their tunable conductivity, easy modification, and biocompatibility. This review analyzes the main trends and trends in the development of the methodology for the application of conductive polymers and their use in biosensors and biofuel elements, as well as describes their future prospects. Approaches to the synthesis of such materials and the peculiarities of obtaining their nanocomposites are presented. Special emphasis is placed on the features of the interfaces of such materials with biological objects.

Cold Non-equilibrium Plasma as a Tool for Air Disinfection and Destruction of Biological Objects

Introduction: The paper presents the results of experiments on the purification of air con-taminated with S. aureus, as well as the destruction of yeast under the action of cold nonequilibrium plasma of a nanosecond streamer corona discharge. Methods: It is shown that plasma is an effective means for destroying both bacteria in the air and biological objects on the surface. The main parameters of the nanosecond streamer corona discharge and their relationship with the operating time of the active plasma components were determined. It was experimentally established that the inactivation time of 80% of S. aureus bacteria with a con-centration of 2.1∙104 KOE m-3 was 0.4 s with a specific energy of 28 J∙l-1. Results: The results of measurements of the dependence of the yeast destruction degree on the yeast size, the time of direct exposure to the nanosecond streamer corona discharge, active elements of cold nonequilibrium plasma, and third-party ultraviolet radiation are presented. Conclusion: A comparison of the results of air disinfection experiments with data on yeast destruc-tion shows that the latter can be used for rapid analysis of the effects of low-temperature plasma on other biological objects.

Rapid-prototyping of microscopic thermal landscapes in Brillouin light scattering spectroscopy.

Since temperature and its spatial, and temporal variations affect a wide range of physical properties of material systems, they can be used to create reconfigurable spatial structures of various types in physical and biological objects. This paper presents an experimental optical setup for creating tunable two-dimensional temperature patterns on a micrometer scale. As an example of its practical application, we have produced temperature-induced magnetization landscapes in ferrimagnetic yttrium iron garnet films and investigated them using micro-focused Brillouin light scattering spectroscopy. It is shown that, due to the temperature dependence of the magnon spectrum, spatial temperature distributions can be visualized even for microscale thermal patterns.

Tuning hyperparameters of doublet‐detection methods for single‐cell RNA sequencing data

Doublet is a major confounder in single‐cell RNA sequencing data analysis. Computational doublet‐detection methods aim to remove doublets from scRNA‐seq data. The performance of those methods relies on the appropriate setting of their hyperparameters. In this study, we explore the optimal hyperparameters for scDblFinder, a cutting‐edge doublet‐detection method. Our optimization utilizes a full factorial design, a response surface model, and 16 real scRNA‐seq datasets. The optimal hyperparameters achieve top doublet‐detection performance under a wide range of biological conditions. Our methodology is applicable to broader computational methods in scRNA‐seq data analysis.BackgroundThe existence of doublets in single‐cell RNA sequencing (scRNA‐seq) data poses a great challenge in downstream data analysis. Computational doublet‐detection methods have been developed to remove doublets from scRNA‐seq data. Yet, the default hyperparameter settings of those methods may not provide optimal performance.MethodsWe propose a strategy to tune hyperparameters for a cutting‐edge doublet‐detection method. We utilize a full factorial design to explore the relationship between hyperparameters and detection accuracy on 16 real scRNA‐seq datasets. The optimal hyperparameters are obtained by a response surface model and convex optimization.ResultsWe show that the optimal hyperparameters provide top performance across scRNA‐seq datasets under various biological conditions. Our tuning strategy can be applied to other computational doublet‐detection methods. It also offers insights into hyperparameter tuning for broader computational methods in scRNA‐seq data analysis.ConclusionsThe hyperparameter configuration significantly impacts the performance of computational doublet‐detection methods. Our study is the first attempt to systematically explore the optimal hyperparameters under various biological conditions and optimization objectives. Our study provides much‐needed guidance for hyperparameter tuning in computational doublet‐detection methods.

Evaluation of efficiency and quality of mechanical cleaning of autopsy tools in ultrasonic cleaners

Discharging their duties, doctors manning autopsy departments and forensic examiners contact infected biological objects and risk contracting infectious diseases. The risk they run is much higher than dangers faced by specialists involved in other aspects of forensic investigations. This study aimed to assess the effectiveness and quality of mechanized cleaning of autopsy tools in ultrasonic cleaners following standard operating procedures. We compared the results of sanitary and bacteriological examination of the said tools washed manually and mechanically, with the help of ultrasonic cleaners. McNemar’s test used in the context of processing of the data allowed revealing the frequency of change of the monitored indicators between the two groups. Mechanical cleaning minimizes direct contact with the tools, allows decontamination of items of complex geometry (including their hard-to-reach parts) without damaging them and ensures high quality of cleaning. With ultrasonic cleaners, mechanized cleaning significantly shortens the time needed to clean medical tools, eliminates the need to wash them manually without compromising their operability, and brings down the risk of workplace injuries and occupational morbidity.