Experimental Samples Research Articles

Influence of the Deformation Degree of Combined Loadings on the Structural and Mechanical Properties of Stainless Steels

Stainless steels have many practical applications requiring various mechanical or chemical demands in the working environment. By optimizing a device used in mechanical experiments for torsional loading, several cylindrical samples were tested (both ends twisted with the same torque value in opposite directions) of 316L stainless steel (SS) to evaluate changes in the structural, chemical, and mechanical characteristics. Initially, the experimental samples were pre-loaded by tension in the elastic range (6%) and then subjected to torsion (772°) at different rates: 5, 10, and 20 mm/min. The experimental sequence consisted of a combined loading protocol with an initial tensile test followed by a subsequent torsional test. Two reference tests were performed by fracturing the samples in both torsion and tension to determine the mechanical strength parameters. The macro- and microstructural evolution of the samples as a function of the torsional degree was followed by scanning electron microscopy. The microhardness modification of the material was observed because of the strain (the microhardness variation from the center of the disk sample to the edge was also monitored). Structurally, all samples showed grain size changes because of torsional/compressive deformation zones and an increase in the degree of grain boundary misorientation. From the tensile and torsional behaviors of 316L SS and the structural results obtained, it was concluded that these materials are suitable for complex stress states in the elasto-plastic range through tensile and torsion. A reduction in Young’s modulus of up to four times the initial value at medium and high stress rates was observed when complex stresses were applied.

Molecular evidence of the inhibitory potential of melatonin against sodium arsenite toxicity.

Sodium arsenite (SA), NaAsO2, is among the most hazardous toxicants, and wide use and presence of this toxicant leads to a severe environmental threat. Exposure to SA is associated with many health concerns, such as the prevalence of cancer and diabetes mellitus type 2 (DMT2). Many studies suggest that SA induces inflammation and biochemical impairments through different mechanisms, including increasing oxidative stress and altering vital genes such as biochemical and anti-inflammatory. Recent studies on melatonin (MLT), a harmless hormone secreted in the body generally for induction of sleepiness, find many beneficial and positive effects. Mitigating different harms and toxicities through different mechanisms, such as antioxidant properties, anti-inflammatory effects, and critical gene regulation, is essential. Due to these findings, this study aimed to evaluate the hypothesis that MLT may ameliorate pancreatic damage caused by exposure to SA. Forty-eight adult healthy male wistar rats aged 7-8 weeks were divided into eight for this research. Group 1 did not receive any intervention. Group 2 received 10mg/kg/day MLT through intraperitoneal (IP) injection. Groups 3, 4, and 5 received 1.5 (1/10 LD50), 5 (1/3 LD50), and 7.5 (1/2 LD50) mg/kg SA, respectively. Groups 6, 7, and 8 were given 1.5 (1/10 LD50), 5 (1/3 LD50), and 7.5 (1/2 LD50) mg/kg of SA along with 10mg/kg/day MLT, respectively, during the last ten days of the experiment. After 28 days of the experiment, the blood and tissue samples of the pancreas were removed for biochemical and pathological examination. MLT attenuates SA toxicity by reducing oxidative stress biomarkers and inflammation markers. Moreover, MLT improves SA exposure's biochemical and functional damages by regulating related genes and pathways. MLT poses protective and preventive effects on the pancreas against exposure to SA. However, MLT's therapeutic and beneficial impacts have great potential for further investigation.

Bell Jar: A Semiautomated Registration and Cell Counting Tool for Mouse Neurohistology Analysis.

For comprehensive anatomical analysis of a mouse brain, accurate and efficient registration of the experimental brain samples to a reference atlas is necessary. Here, we introduce Bell Jar, a semiautomated solution that can align and annotate tissue sections with anatomical structures from a reference atlas as well as detect fluorescent signals with cellular resolution (e.g., cell bodies or nuclei). Bell Jar utilizes Mattes mutual information-directed B-spline transformations to achieve precise alignments, even with damaged sample tissues. While user input remains a requirement for fine-tuning section matches, the platform streamlines the process, aiding rapid analyses in high-throughput neuroanatomy studies. As a standalone desktop application with a user-friendly interface, Bell Jar's performance, which surpasses traditional manual and existing automated methods, can improve the reproducibility and throughput of histological analyses.

Rapid Detection of Soil Available Phosphorus using Capacitively Coupled Contactless Conductivity Detection

Background: In China, the traditional method for analyzing soil available phospho-rus is inadequate for large-scale soil assessment and nationwide soil formulation demands. To address this, we propose a rapid and reliable method for soil-available phosphorus detection. The setup includes an on-site rapid pre-treatment device, a non-contact conductivity detection device, and a capillary electrophoresis buffer solution system composed of glacial acetic acid and hydroxypropyl-β-cyclodextrin. Methods: The on-site rapid pre-treatment process includes fresh soil moisture content detec-tion (moisture rapid detector), weighing (handheld weighing meter), stirring (handheld rapid stirrer), and filtration (soil rapid filter) to obtain the liquid sample, and direct injection (capil-lary electrophoresis detector). The phosphate ion detection parameters include capillary size, separation voltage, injection parameters, and electric injection. We used Liaoning brown soil, Henan yellow tidal soil, Heilongjiang black soil, and Anhui tidal soil as standard samples. Additionally, we used mathematical modeling methods and machine learning algorithms to analyze and process research data. Results and Conclusion: Following calibration with standard samples, the experimental blind test samples demonstrated conformity with the national standard method, exhibiting a relative standard deviation of less than 3%. The proposed pre-treatment device and non-contact con-ductivity detector are powered by lithium-ion batteries, rendering them ideal for extended field operations. The non-contact conductivity detector obviates the need for direct contact with test samples, mitigating environmental pollution. Furthermore, the neural network model exhibited the highest level of goodness of fit in chemical data analysis.

Improve the visualization effect of fingerprint immunolabeling based on biotin-avidin system.

Immunolabeling based on fluorescence is a new technique that has been recently applied in the field of forensic science. In this paper, a new immunofluorescence method based on signal amplification was applied to develop fingermarks and improve the quality of pattern recognition with clear ridge details and high contrast. The high affinity between biotin and avidin and the one-to-many binding mode can connect several fluorescent groups together to achieve a signal amplification effect. The results indicated that the fluorescence intensity of the fingermark sample, as displayed by the biotin-avidin signal amplification system (BAS), was nearly three times higher than that revealed by previous immunolabeling methods based on fluorescence. Specifically, more fluorescent chromophores were bound to the friction ridges in BAS. Two proteins were selected as experimental target proteins for fingermark immunofluorescence visualization to optimize the visualization effect. The results showed that compared to keratin 1, dermcidin as the target protein in BAS achieved a more desirable effect, with 88.9% of the experimental samples left on nonporous objects having identification value. This method provides new insights for the development of fingermark spectra and is expected to become an effective and safe technology in the field of forensic science.

Determining the reliability of the origin of Siberian sturgeon based on the results of microsatellite analysis and genetic similarity coefficients

In the present study, a statistical approach to determining genetic similarity in tetraploid animals was developed using the example of aquacultured Siberian sturgeon. The feasibility of using genetic similarity parameters to determine kinship relations, in particular, to establish the maternal and paternal origin of individuals, was determined. Genetic profiles of the parental population and their offspring were obtained by analyzing 7 microsatellite loci. As a result of the validation study, it was revealed that the ancestral groups of individuals were correctly determined on average in 95.39% of cases with a range of values from 79.17 to 100% in different experimental samples. The created algorithm does not always allow to correlate parental individuals and descendants with 100% accuracy, but it can identify genetically close groups within the herd. Thus, the developed approach has a number of prospects for application both in genetic studies and in the breeding process.

An analytical study of the availability of comprehensive knowledge marketing management in Iraqi sports institutions

Objective: The current study aimed to prepare a measure for comprehensive knowledge marketing management. In the Iraqi sports institutions under study, identifying the extent of each dimension of comprehensive knowledge marketing management. Research methodology: This study relied on appropriate scientific methods, mainly represented by the descriptive method and the analytical method, and on the case study method because it suits the nature of the study. The study population was determined from the administrative cadres in the Iraqi Sports Federation, and the research sample numbered (86) and was represented as follows: The preparation sample numbered (50) and a percentage amounted to (58.13%), the sample of the exploratory experiment was (5), with a percentage of (5.81%), and the main experiment sample (application sample) numbered (31) and had a percentage of (36.04%). Result: that the value of the arithmetic mean for the comprehensive marketing knowledge management scale reached (70.75) with a standard deviation of (20.84), which is less than the value of the hypothesized mean of (114), and the significance value of the error reached (0.00), which is less than the significance level of (0.05), and this is an indication of the weakness of sports institutions in comprehensive marketing knowledge management, and the researchers attribute the reason for this to the fact that sports institutions do not develop objectives related to knowledge management are achievable. Conclusions: There is a weakness in the sports institutions under study in managing comprehensive knowledge marketing, and there is a weakness in marketing planning.

The effects of the integrative strategy on fostering reflective thinking and imparting basic basketball offensive techniques to female students

Objective: The objective of this study is to develop instructional materials that teach fundamental basketball skills to female students enrolled in the first year of the College of Physical Education and Sports Sciences for Girls at the University of Baghdad while also encouraging reflective thinking (RT). Research methodology: the researcher chose the experimental methodology with the two equal group's method. Finding the community and choosing the right sample for the study's kind and goals are essential to the accomplishment of any research project. A sample for the primary experiment was picked at random after the researcher confirmed the students' first-year basketball curriculum. This study community consisted of (40) fourth-year female students for the year (2022-2023). The number of students was split into (2) groups. Twenty students in-group (B) represent the experimental group, which follows the curriculum that the researcher has developed in an integrated, strategic manner. Result: The method of selecting the (integrative) strategy that was given to the students is right to the level of their skills and characteristics, as well as while taking into consideration the distinct characteristics among them by means of the presentation offered by the stations—from a complete demonstration of the skill, then a slow delivery, then the appearance of the integrated strategy—is also attributed as the reason for the superiority of the members of the experimental group. Concludes: The study concludes that the integrated approach has a beneficial impact on the post-tests for reflective thinking and the growth of basketball skills.

Colorimetric and Textile Properties of Huacaya Alpaca Fibers Dyed With Cochineal: A Sustainable Approach

Objective: To investigate the colorimetric and textile properties of Huacaya alpaca fibers dyed with cochineal, promoting a sustainable approach in the textile industry through the use of natural resources and traditional methods, improving product quality and minimizing environmental impact. Theoretical Framework: The main concepts and theories that support the research on the colorimetric and textile properties of Huacaya alpaca fibers dyed with cochineal dye are presented, focusing on sustainability. Method: The methodology included a randomized experimental design with a factorial arrangement to evaluate the impact of different mordants and concentrations of cochineal dye on the colorimetric and textile properties of alpaca fiber, with data collection through experimental methods. Results and Discussion: The results showed significant differences in colorimetry parameters, textile characteristics, and chemical bands, depending on the type of mordant and dye concentration used. Wash fastness was notably high in the MAL-2 and MCOL-2 samples, indicating the effectiveness of sustainable practices. However, the study's limitations might be related to the experimental design, sample selection, and analysis method employed. Research Implications: The results promote the use of natural dyes in textile production, encouraging sustainable practices, reducing harmful chemicals, and conserving biological resources, which influences conservation policies and supports fair trade and local products. Originality/Value: This study applies innovative methodologies to evaluate Huacaya alpaca fibers dyed with cochineal, promoting sustainability, the use of natural dyes, conservation of biological resources, fair trade, and sustainable management policies.

Compressive Properties of Composite Sandwich Structure with Fractal Tree-Inspired Lattice Core

A novel sandwich structure of a fractal tree-like lattice (SSFL) is proposed. The geometry characteristics were constructed based on the fractal tree-like patterns found in many biological structures, such as giant water lilies and dragon blood trees. The compressive performance of the proposed structures with different fractal orders was experimentally and numerically investigated. The experimental samples were made by 3D printing technology. Axial compression tests were conducted to study the compressive performance and failure mode of the SSFLs. The results indicated that the new structure was good at multiple bearing and energy absorption. The finite element method (FEM) was performed to investigate the influence of geometry parameters on the compression behaviors of the SSFLs. The findings of this study provide an effective guide for using the fractal method to design lattice structures with a high bearing capacity.

АМИНОКИСЛОТЫ В ВИНАХ ИЗ ДОНСКИХ АВТОХТОННЫХ СОРТОВ ВИНОГРАДА

The purpose of research is to study the quantitative indicators of amino acids in wines from white autochthonous grape varieties of the Don ampelographic collection named after Ya.I. Potapenko (Novocherkassk). Objects: must and wine from white technical grape varieties: Sibir'kovyj, Kumshackij belyj, Belobulanyj. Research was carried out on the basis of the laboratory of ampelography and technological evaluation of grape varieties. Experimental samples were produced in batches (10-30 liters of each sample) according to the technology for preparing dry white wines. Clarification, fermentation and further maturation of the wine material took place in glass containers. The following indicators were determined in the must: pH, glucoacidometric index (GAI), technical maturity index (TMI). After completion of fermentation, the following indicators were determined: the content of alcohol, titratable and volatile acids, residual sugars and reduced extract. The organoleptic characteristics of the studied wine varieties were carried out according to a 10-point system by the tasting commission of the institute. Derivatives of amino acids are involved in the addition of aroma, taste of wine and determine its high quality, and also serve as the basis for yeast nutrition. In the studied samples, 13 amino acids were found. According to their total accumulation the Sibir'kovyj variety – 1451.43 mg/dm3 stood out. The samples Belobulanyj and Kumshackij belyj (943.2 and 944.97 mg/dm3) are practically at the same level. Based on the data obtained, it can be concluded that the accumulation of amino acids is a varietal feature of grapes.

СОСТАВ КОМПОНЕНТОВ, ВЛИЯЮЩИХ НА ВКУС ВИНА ИЗ СОРТА КРАСНОСТОП ЗОЛОТОВСКИЙ В ЗАВИСИМОСТИ ОТ ПРОВОДИМЫХ АГРОТЕХНИЧЕСКИХ ПРИЕМОВ

The aim of the study is to identify the features of the composition of biochemical indicators affecting the taste of dry red wines from the autochthonous grape variety Krasnostop Zolotovsky depending on the load of bushes with shoots. Objectives: to conduct a physicochemical and sensory analysis of the experimental wines. Objectives of the study: dry red wines from the technical grape variety Krasnostop Zolotovsky, grown in the vineyards of the All-Russian Research Institute of Viticulture and Winemaking. The studies were conducted at the laboratory for quality control of viticulture and winemaking products of the All-Russian Research Institute for Viticulture and Winemaking, a branch of the Federal State Budgetary Scientific Institution FRANTS. As part of the study, wines were prepared using the microwinemaking method in accordance with the following experimental options: B-1 – with a load of 20 shoots per bush (s/c); B-2 – 25 shoots per bush; B-3 – 30 shoots per bush; B-4 – 35 shoots per bush; B-5 – with a load of 40 shoots per bush. Analysis of the obtained data on the study of the composition of biochemical components affecting the taste of dry red wines from the autochthonous grape variety Krasnostop Zolotovsky depending on the load of the bushes with shoots showed that the sum of organic acids in the studied samples was within 6.7–8.1 g/dm3 with their highest content in Krasnostop Zolotovsky B-4 (35 p/k). The amount of tartaric acid was about 50 % of the total amount of acids in the wine. Variants with a bush load of 30 (B-3) and 35 (B-4) shoots per bush were distinguished by the accumulation of phenolic and coloring substances. The highest content of malic acid was noted in the experimental sample B-5 (load 40 p/k). The ratio of mass concentrations of tartaric and malic acids in all experimental variants was > 2, which contributes to obtaining a more harmonious taste. The highest content of lactic acid was observed in B-3 (1.01 g/dm3) and B-4 (0.85 g/dm3), these same variants were distinguished by the softest and roundest taste. The highest content of reduced and residual extract was noted in B-3 and B-4, and the least amount was in B-2. As a result of sensory analysis, it was revealed that the most complete, meaningful taste and complex aroma were distinguished by the experimental samples Krasnostop Zolotovsky B-3 and B-4 (8.9 points each). In these same variants, the highest content of phenolic, coloring and extractive substances was observed.

ИЗМЕНЕНИЕ АМИНОКИСЛОТНОГО СОСТАВА БЕЛКА ЗЕРНОВЫХ ТЕКСТУРАТОВ И МУКИ ПРИ ХРАНЕНИИ РАЗЛИЧНЫМИ СПОСОБАМИ

The aim of the study is to investigate changes in the amino acid composition of grain textured flour proteins during storage using different methods. The object of the study was textured flours obtained from barley and oat grain extrudates, barley and oat flour. The experimental samples were stored using different types of packaging with different barrier properties. Samples stored in bulk were selected for analysis directly at the enterprise. The amino acid composition was determined using a verified capillary electrophoresis system at the Research and Testing Center of the Krasnoyarsk State Agrarian University. The limiting amino acids in general for most storage periods and methods were: for oat flour – tryptophan, leucine + isoleucine, for barley flour – lysine, leucine + isoleucine; for textured flours from grain crop extrudates – lysine, tryptophan, leucine + isoleucine. The calculated index of essential amino acids (INA) had a value greater than 1, but did not characterize the protein of flour and texturate from grain extrudate as ideal, acquiring such a value due to the larger proportion of excess amino acids. The protein of oat grain extrudate texturate was less complete compared to the protein of the corresponding type of flour with storage periods of 1 and 12 months. The determined total content of calculated amino acids with the storage option in opaque and transparent polymeric material with an air environment inside the package was higher compared to other options. This allows us to consider these types of packaging as the most optimal of all those considered for storage.

Effects of Tasimelteon Treatment on Traumatic Brain Injury Through NRF-2/HO-1 and RIPK1/RIPK3/MLKL Pathways in Rats.

Secondary brain damageafter traumatic brain injury (TBI) involves oxidative stress, neuroinflammation, apoptosis, and necroptosis and can be reversed by understanding these molecular pathways. The objective of this study was to examine the impact of tasimelteon (Tasi) administration on brain injury through the nuclear factor erythroid 2-related factor 2 (NRF-2)/heme oxygenase-1 (HO-1) and receptor-interacting protein kinase 1 (RIPK1)/receptor-interacting protein kinase 3 (RIPK3)/mixed lineage kinase domain-like (MLKL) pathways in rats with TBI. Thirty-two male Wistar albino rats weighing 300-350g were randomly divided into four groups: the control group, trauma group, Tasi-1 group (trauma + 1mg/kg Tasi intraperitoneally), and Tasi-10 group (trauma + 10mg/kg Tasi intraperitoneally). At the end of the experimental phase, after sacrifice, blood samples and brain tissue were collected for biochemical, histopathological, immunohistochemical, and genetic analyses. Tasi increased the total antioxidant status and decreased the total oxidant status and oxidative stress index. In addition, Tasi caused histopathological changes characterized by a markedly reduced hemorrhage area in the Tasi-1 group. Normal brain and meningeal structure was observed in rats in the Tasi-10 group. Immunohistochemical analysis indicated that Tasi also decreased the expression of interferon-gamma, caspase-3, and tumor necrosis factor-alpha in the brain tissue. Although NRF-2 and HO-1 expression decreased, RIPK1/RIPK3/MLKL gene expression increased due to trauma. However, Tasi treatment reversed all these findings. Tasi protected against brain injury through the NRF-2/HO-1 and RIPK1/RIPK3/MLKL pathways in rats with TBI.

ВОЗМОЖНОСТЬ ИСПОЛЬЗОВАНИЯ ПЛОДОВ ГРУШИ И ОБЛЕПИХИ ДЛЯ ОБОГАЩЕНИЯ ПЕЧЕНОЧНЫХ ПАШТЕТОВ

The aim of the study is to establish the possibility of simultaneous use of pear and sea buckthorn fruits in chicken liver pate recipes to create a product containing functional substances. Objectives: to determine the rational dosage of pear and sea buckthorn fruits in the chicken liver pate recipe, providing the best quality indicators of the product; to conduct a tasting assessment of the product; to develop a basic technological scheme for obtaining the product. The object of the study is chicken liver pate. Among the many fruit crops grown in the agroecological conditions of the Krasnoyarsk Region, a large number of antioxidants are found in pear and sea buckthorn fruits. Plant components (pears and sea buckthorn fruits) were added to the experimental samples in various dosages instead of chicken liver. Pears and sea buckthorn fruits were collected in the vicinity of Kansk during their technical maturity. The organoleptic and tasting evaluation of finished products was carried out in accordance with GOST R 55334-2012 on a 5-point scale. Based on preliminary experimental studies, pears were added in the amount of 22; 23 and 24 %, sea buckthorn fruits – 8; 9; 10 %. The rational dosage of the introduced ingredients is: pears – 24 %, sea buckthorn fruits – 10 % instead of meat raw materials. A basic scheme for the production of liver pate from chicken liver with the addition of pears and sea buckthorn is proposed. The addition of pears and sea buckthorn fruits to the recipe for liver pates improves taste, enriches with physiologically significant components contained in plant materials, and also diversifies the range of canned liver.

ПЕРСПЕКТИВЫ РАЗВЕДЕНИЯ МУХИ ЧЕРНАЯ ЛЬВИНКА ДЛЯ РЕШЕНИЯ ПРОБЛЕМ БЕЛКОВОГО ПИТАНИЯ В ОРГАНИЧЕСКОМ СЕЛЬСКОМ ХОЗЯЙСТВЕ

The objective of the study is to determine the nutritional value of the black soldier fly at all stages of its development cycle, as well as to predict the efficiency of feeding fly processing products to egg-producing quails by calculating rations with the inclusion of the most nutritionally valuable raw materials. Objectives: study of the nutritional value of the experimental material; development of the experiment scheme; calculation of rations according to the experimental scheme using the KormOptima software. The studies were conducted in the scientific laboratory Feed and Metabolism of the Stavropol State Agrarian University. At the first stage, analyzes were carried out to determine the nutritional value of the fly at different stages of its development from larva to dead bodies. Quality indicators were determined in accordance with approved methods. When drawing up the experiment scheme for groups of egg-producing quails, 1 and 5 % of larvae and 1 and 5 % of prepupa were added to the main ration, thereby forming 5 groups of quails, including a control group. The rations of the control and experimental groups of quails aged 55 days were calculated in accordance with the standard of GOST 28460-2014. Egg-producing quails were selected using the method of pairs of analogues with 35 heads per group. The obtained protein product turned out to be highly nutritious: crude protein – 40–45 %, crude fat – up to 42 %, this provides high energy value, which is beneficial for balancing poultry rations. The amino acid composition of the black soldier fly larvae corresponds to the amino acid profile of animal feed, especially in terms of the high content of limiting amino acids. Based on the obtained nutritional value of the experimental samples, rations for egg-producing quails were calculated. When introducing 1 and 5 % of larvae into the diet, the cost decreased by 0.58 and 3.95 %, respectively, compared to the control. When introducing prepupa into the diet at 1 and 5 %, the price decreased by 0.75 and 3.77 %, respectively.

MEDIA EFFECTIVENESS OF ANDROID-BASED E-GEA APPLICATION TO IMPROVE CRITICAL THINKING SKILLS

<p data-pm-slice="0 0 []">This study aims to test the effectiveness of Android-based E-GeA learning media in improving the critical thinking skills of grade X students of SMA Negeri Kebakkramat, Karanganyar. The E-GeA application for Electronic Geography Adventure is designed to support geography learning through interactive features, such as learning videos, materials, animations, and pre-test and posttest-based exams. The study used an experimental and purposive sampling technique on 36 students in grades X-5. The data were analyzed using normality, n-gain, and t-test tests. The results showed that the t-test results showed a significant difference between the pre-test 30 and post-test 86 scores, with 94% of students achieving KKM scores. This study proves that E-GeA learning media improves students' critical thinking skills. These findings provide recommendations for integrating technology in geography learning to support improving the quality of education and skills in the 21st century.</p>

ИСПОЛЬЗОВАНИЕ НЕТРАДИЦИОННОГО СЫРЬЯ В ХЛЕБОПЕЧЕНИИ

Currently, there is a growing demand for bakery products. To expand the range and increase the nutritional and biological value of finished products, various herbal supplements are used. One such ingredient in wheat bread recipes can be spinach. The purpose of the study: to reveal the possibility of introducing chopped dried spinach into the recipes for the production of wheat bread as an enrichment additive, to expand the range of functional products. Tasks: to study the effect of chopped dried spinach on the main indicators of wheat bread; to determine the possibility of using chopped dried spinach in bakery production. Trial baking was carried out on the basis of the Belgorod State Agrarian University at the Department of Production and Processing Technologies of the Agricultural Industry. To make bread, 3 %, 5 and 10 % spinach was added to the dough by weight of baking wheat flour. With an increase in the amount of dried chopped spinach added to the dough, the taste of the finished product is enhanced; the smell becomes brighter and more pronounced, and the color is darker and richer. In terms of crumb moisture, all samples correspond to GOST, the lowest humidity was observed in the control sample – 37.8 %, in experimental samples it was: in 3 % spinach – 38.6 %, in 5 % spinach – 40.0, 10 % spinach – 38.1 %. The acidity of the test samples turned out to be higher than in the control by 33.3 %, 62.5, 79.2 %, respectively (control – 2.4 degrees). The porosity of the crumb both in the control and in the experimental samples is more than 72 %, and is in the range of 75.5–76.3 % for all bread products, which means that this indicator also complies with the standards of GOST R 58233-2018 “Bread from wheat flour. Specifications". Based on test baking and laboratory studies, it was found that the optimal dose of chopped dried spinach is 5 % by weight of the flour.

Atomic force microscopy combined with microfluidics for label-free sorting and automated nanomechanics of circulating tumor cells in liquid biopsy.

Liquid biopsies are expected to advance cancer management, and particularly physical cues are gaining attention for indicating tumorigenesis and metastasis. Atomic force microscopy (AFM) has become a standard and important tool for detecting the mechanical properties of single living cells, but studies of developing AFM-based methods to efficiently measure the mechanical properties of circulating tumor cells (CTCs) in liquid biopsy for clinical utility are still scarce. Herein, we present a proof-of-concept study based on the complementary combination of AFM and microfluidics, which allows label-free sorting of individual CTCs and subsequent automated AFM measurements of the mechanical properties of CTCs. With the use of a microfluidic system containing contraction-expansion microchannels, specific cancer cell types were separated and harvested in a marker-independent manner. Subsequently, automated AFM indentation and force spectroscopy experiments were performed on the enriched cells under the precise guidance of the label-free identification of cells using a deep learning optical image recognition model. The effectiveness of the presented method was verified on three experimental sample systems, including mixed microspheres with different sizes, a mixture of different types of cancer cells, and a mixture of cancer cells and blood cells. The study illustrates a feasible framework based on the integration of AFM and microfluidics for non-destructive and efficient nanomechanical phenotyping of CTCs in bodily fluids, which offers additional possibilities for the clinical applications of AFM-based nanomechanical analysis and will also benefit the field of mechanobiology as well as cancer liquid biopsy.

ПРОБООТБОРНИК ДЛЯ КОНТРОЛЯ КАЧЕСТВА СУШКИ ЗЕРНА

The objectivity of assessing the quality of stored grain depends on the efficiency of the grain samplers used and the technologies for their use. An analysis of commercially available samplers and new technical solutions in the development of technological equipment for taking grain samples showed the need to create a small-sized portable grain sampler for taking samples in hard-to-reach places and with small storage volumes. The purpose of the study is the development of technological equipment for sampling grain stored after drying. Research objectives: development of design and technical documentation, production and testing of an experimental sample of the sampler. In the course of the research, the design of technological equipment for sampling was developed and an application for a patent was filed, a patent for the invention No. 209612 “Grain sampler” was received. The materials of the paper include a kinematic diagram, a description of the design and the principle of operation of the sampler. According to the presented kinematic scheme, a prototype sampler was made and experimental studies were carried out to test it at a grain processing enterprise. The operating parameters of the experimental sample of the sampler were determined. Sampling was carried out using new equipment, which showed that the capacity of the sampler receiving hopper was 200 g, and for the surface of a grain lot of 100 m2 weighing 20 tons, it is necessary to take grain samples at 5 points of the total surface of the lot: in the center and at four points with an indent of 1 meter from the edge of the boundaries of the surface of the batch, while the grain of the first samples was taken at a depth of 15 cm, the second samples were taken in the middle of the surface, the third grain samples were taken from the bottom of the bunker. The mass of the total (combined) sample was about 3 kg and consisted of 15 patterns (samples) of grain. It has been established that the use of a new design grain sampler makes it possible to take grain samples with an error (in accordance with regulatory documents) up to ±5 % by weight.