Principle Of Analogy Research Articles

Plasma lipid profile and sex hormone levels in rabbits under paraceta-mol-induced oxidative stress

Changes in the redox balance at different levels, which lead to the accumulation of toxic radicals against the background of a decrease in the content of redox-active compounds, i.e., a state of oxidative stress (OS), are considered the leading pathogenetic factor in pathological conditions. Processes of peroxide oxidation of biological substrates, especially cell membrane lipids and lipophilic compounds have both regulatory and pathological effects in the body of animals and humans. For now, it remains relevant to establish the regularities of interaction of metabolism during OS development. Among the large number of existing OS models, attention is drawn to those that can be reproduced in clinical practice, as a complication of treatment measures or an error in the medical strategy, due to a constant influence on peroxidation processes in the body. Important among such means is paracetamol (acetaminophen, APAP) – one of the most common antipyretic and analgesic drugs. In addition to the known hepato-, nephro- and neurotoxic effects of its long-term and/or excessive use, there are data on reproductive toxicity and disorders of lipid metabolism. Therefore, the aim of our work was to determine the lipid profile and the level of sex hormones in male rabbits during paracetamol-induced OS. The study was performed on male rabbits of the Khila breed. According to the principle of analogs, a control group (n = 12) was formed, which were kept on a standard diet, and an experimental group (n = 12), whose animals were simulated the state of OS by oral injection of a solution of paracetamol with food at a dose of 300 mg/kg of weight body once during 21 days. The following results were obtained by determining the dynamics of changes in biochemical indicators in the rabbit body during chronic injection of paracetamol: in the rabbits of the experimental group, after the injection of paracetamol, the level of diene conjugates was 63.0 % higher, and the content of thiobarbiturate-active products was 1.26 times higher (P ˂ 0.05). A decrease in the activity of the antioxidant defence system was also noted – the amount of reduced glutathione decreased by 35.4 %, and the activity of superoxide dismutase decreased by 25.6 % (P ˂ 0.05). The obtained changes were consistent with the comprehensive indicator of total antioxidant activity, which on the 21st day of the experiment was 34.1 % lower than the values of the control group (P ˂ 0.05). At the same time, the level of steroid hormones also changed during the study – the level of total testosterone gradually decreased (on the 21st day – by 22.8 %, and at the end of the experiment – by 30.9 %, P ˂ 0.05), while the level of 17β-estradiol had an upward trend and on the 21st day was higher than the control indicators by 10.7 % (P ˂ 0.05). Significant changes in lipid metabolism were found in male rabbits – the total cholesterol content on the 21st day of the experiment exceeded the data of control animals by 25.3 %, the level of triacylglycerols – by 42.3 %, and the content of low-density lipoprotein cholesterol also increased by 1.1 times (P ˂ 0.05), and the high-density lipoprotein cholesterol level, on the contrary, was reduced by 17.0 % (P ˂ 0.05). In general, the obtained results indicate the relationship between the development of OS with changes in lipid metabolism and the balance of sex hormones, which allows us to use the model of paracetamol-induced OS in rabbits for further research.

ОПЫТ ЛЕЧЕНИЯ ПОСЛЕРОДОВОГО ЭНДОМЕТРИТА У КОРОВ

The purpose of the study is to conduct a comparative analysis of the therapeutic effectiveness of a local antiseptic drug based on tea tree essential oil for acute postpartum catarrhal endometritis in cows. The study was conducted at the Department of VNB, Obstetrics and Physiology of Farm Animals of the Krasnoyarsk State Agrarian University, on the basis of the dairy farm of the Balakhta District of the Krasnoyarsk Region. The object of the study is red-motley cows. Research methods: obstetric and gynecological medical examination of breeding stock; the diagnosis of acute postpartum catarrhal-purulent endometritis was established during a clinical and gynecological examination of fresh cows, which inclu-ded thermometry, rectal and vaginal examination. The diagnosis was considered confirmed when pathological discharge of a catarrhal nature appeared from the uterus during rectal massage. Two experimental groups of fresh cows were formed according to the principle of analogues (based on live weight, age, lactation, clinical manifestation of the form of acute endometritis). In the 1st experimental group, scheme № 1 was used: a 25 % oil solution of tea tree essential oil was administered intrauterinely in a dose of 20 ml daily once a day until clinical recovery; eleovit 8 ml was administered intramuscularly on the 1st and 5th days of treatment; uteroton 10 ml was administered intramuscularly daily once a day for 3 days; 0.05 % chlorhexidine solution 200 ml – intravaginally; rectal massage of the uterus once a day. In the 2nd experimental group, treatment regimen № 2 was used, which differed from regimen № 1 by using a 50 % oil solution of tea tree essential oil in a similar dosage. The best therapeutic effect in the treatment of acute catarrhal endometritis was obtained using scheme № 2 using a 50 % oil solution of tea tree essential oil. Du¬ring the seven-day course of treatment, therapeutic effectiveness was obtained in 60.0 % of cases; prolongation of the course of therapy led to the recovery of all animals in this experimental group. The ave¬rage duration of treatment for the group was 8.0 days.

Creativity as an implementation of the idea of the integrity of the world

The article is devoted to the study of the areas of realization of creative activity, justification of the possibility of creativity as a process of creation of qualitatively new values, mechanisms of creativity, the main of which is intuition. One of the key questions, the answer to which determines the possibility of explaining creativity, is the choice of deterministic or irrational representation of the world. The author makes a reasoned choice in favor of a deterministic view of the world, within the framework of which intuition, and thus creativity, receive an adequate explanation. The research methodology in this article is based on the idea of creativity as a process manifested in the form of intuition, through which the mind reaches areas of world understanding inaccessible to reason based on reproductive thinking. As a result of the research conducted by the author, the key role of intuition in creativity has been established. Intuition, in its turn, is a consequence of isomorphism of forms and laws in different subject areas, at different levels of the universe. A generalization of the use of isomorphism in practice takes the form of the principle of similarity or analogy. The ability of human being to intuition is the result of his multisystem integration into many systems: physical and biological world, social and cultural environment, system of professional knowledge and relations, etc. The representation of the integrity of the world is an imperative of creativity. On the other hand, creativity is an indispensable tool for creating a holistic representation of the world. By virtue of its defining internal mechanisms, everything valuable that creativity gives birth to becomes a part of the holistic world. It can be stated that in the process of creativity the representation of its integrity is implanted (reproduced and used as a tool).

Anatomical, pathological, and histological features of experimental respiratory infection of birds by biofilm-forming bacteria Staphylococcus aureus.

The pathogenesis of staphylococcal infections is mediated by virulence factors, such as enzymes, toxins, and biofilms, which increase the resistance of microorganisms to host immune system evasion. Testing and searching for standardized multi-level algorithms for the indication and differentiation of biofilms at the early stages of diagnosis will contribute to the development of preventive measures to control the critical points of technology and manage dangerous risk factors for the spread of infectious diseases. This research aimed to study the main stages of Staphylococcus aureus biofilm formation in in vitro experiments and to analyze the dynamics of respiratory syndrome development in chickens infected with these bacteria. Experimental reproduction of the infectious process was performed using laboratory models: 10-day-old White Leghorn chickens (n = 20). Before the experiments, the birds were divided into two groups according to the principle of analogs: Group I (control, n = 10): the birds were intranasally inoculated with 0.5 cm3 of 0.9% NaCl solution; Group II (experiment, n = 10): the birds were intranasally inoculated with a suspension of S. aureus bacteria, 0.5 cm3, concentration 1 billion/cm3. Colonization of individual areas of the substrate under study in vitro occurred gradually from the sedimentation and adhesion of single motile planktonic cells to the attachment stage of microcolony development. Staining preparations with gentian violet due to the "metachromosia" property of this dye are a quick and fairly simple way to differentiate cells and the intercellular matrix of biofilms. Fixation with vapors of glutaraldehyde and osmium tetroxide preserves the natural architecture of biofilms under optical and scanning electron microscopy. Pure cultures of S. aureus microorganisms were isolated from the blood, lungs, small intestine, liver, kidneys, and spleen after 5-10 days during experimental infection of chickens. Clinical signs of respiratory syndrome developed within 5-6 days after infection. Acute and subacute serous-fibrinous airsacculitis, characterized by edema and thickening of the membranes of the air sacs and the presence of turbid, watery, foamy contents in the cavity, was the most characteristic pathomorphological sign. The signs of acute congestive hyperemia and one-sided serous-fibrinous pneumonia developed with significant thickening of fibrinous deposits. In Garder's gland, there was an increase in the number of secretory sections, indicating hypersecretion of the glands. In the lymphoid follicles of Meckel's diverticulum, leukocytes, usually lymphocytes, and pseudoeosinophils were detected. Hydration and heteromorphism of the internal environment of biofilms determine the localization of differentiated cells in a three-dimensional matrix for protection against adverse factors. The most characteristic pathomorphological sign was the development of acute and subacute serous-fibrinous airsacculitis when reproducing the infectious process in susceptible models. There was a significant thickening of fibrinous deposits and signs of acute congestive hyperemia and one or two serous-fibrinous pneumonia developed.

In Memory of the Q-File

Discussion of “digital performance” is preoccupied with themes of fluidity, variation, ambiguity, and resistance to rigid categorization. And yet these themes correspond more closely to analog principles. The digital ethos indicates regularity, precision, and the elimination of ambivalence. The rationalized industrial practices of stage management, blocking and, in particular, lighting cues prioritize the precisely timed and accurate reproduction of stage images through the instant recall of digital memory.

Peculiarities of the effect of zinc chelate on prooxidant-antioxidant homeosta-sis in the blood of sows and their relationship with the reproductive capacity

During the last decades, research has been actively conducted to increase the reproductive capacity of sows. It was determined that during puberty, the sow’s body actively assimilates nutrients that should provide for their own needs and embryos and creates a reserve for the lactation period. The study aimed to determine the influence of zinc in the form of chelate on the state of prooxidant-antioxidant homeostasis on the reproductive capacity of sows. In the experiment, 45 heads of the Large White breed sows were used, and they were selected and divided into groups (5 heads each) according to the principle of analogs. The norms fed barren and farrowing sows according to their physiological state. The diet of the control group of sows from sexual rest to the 28th day of farrowing remained unchanged; the 1st experimental group – MD+5 % Zinc in the form of zinc chelate, the II experimental group – MD+10 % Zinc in the form of Zinc chelate. Additional feeding of biologically active compounds was stopped one day before farrowing. During the phase of sexual rest, estrus, on the 90th and 104th days of farrowing, the day of farrowing, as well as on the 5th and 28th days of the suckling period, blood was taken from sows and their piglets to determine the state of PAH. It has been determined that in the blood of sows, the periods of the reproductive cycle determine the peculiarities of the formation of prooxidant-antioxidant homeostasis. In particular, during estrus, there is an intensification of peroxide oxidation processes – the content of diene conjugates increases by 56.9 %, TBC-active compounds by 12.3 %, and the level of low molecular weight antioxidants – reduced glutathione decreases (Р < 0.001). This is accompanied by a significant increase in the activities of antioxidant enzymes – superoxide dismutase (Р < 0.05) and catalase (Р < 0.05). It was found that the intensification of peroxide oxidation processes is intensified on the day of farrowing of sows – the content of diene conjugates increases by 26.6 % and TBC-active compounds by 31.8 % with a further decrease during lactation to the level of sexual rest. Animals that received zinc in the form of zinc chelate 5 % above the norm were characterized by a lower intensity of peroxide oxidation processes. Additional feeding of zinc in the form of zinc chelate to sows by 10 % more than the norm is accompanied by a decrease in fertility (Р < 0.05), the number of live piglets (Р < 0.05), litter weight at birth by 10.0 % and litter weight at weaning – 11.6 %. Sows that received this feed supplement of microelement 5 % above the norm are characterized by higher fertility by 4 % and litter weight at birth by 4.2 %.

Towards A 21st Century Systematize the Ideas; COVID-19, Sustainability and Discourse of SDG, (Sustainable Development Goals), The Cities and Housing Models

The research creates a theoretical basis for examining the metamorphic changes and transformations in urban and housing planning with the interaction created by the latest epidemic in the world, which is moving towards a period related to climate problems. The first quarter of the 21st century witnessed an unexpected event: Humanity found itself in the middle of a pandemic considered temporary, it would be permanent and change the world dramatically. The post-COVID-19 period has led to significant and permanent changes in our lives, from urban planning to housing typologies. The study aims to understand the changing dynamics in the post-pandemic period that converges on the same goal with SDG, (Sustainable Development Goals), as continuity by updated dialogues, and discourses on literature. This research focuses on the SDG, (Sustainable Development Goals), and the post-pandemic period, analysis of two phenomena separated, analogous paradigms or intertwined. The findings of the public perception are there is a distinction between sustainability and pandemics considered dissimilar processes, they contain similarities. Contrary to common ideas, the pandemic was a catalyst for sustainability, and these two concepts contain analogous ideas and principles. In conclusion, it is revealed that they both concentrated on similar ideas; SDG, (Sustainable Development Goals) is “health”, and pandemic is the “healthy city” concept like; clean air, zero carbon, living healthy and safely in airy and green areas, etc.

Stationary response of the system “Cylindrical shell – viscoelastic filler” to the effect of a moving load

The paper considers the stationary response of the system “cylindrical shell - viscoelastic filler” to the action of a moving load. The filler and the shell were assumed to be viscoelastic. Using the principle of analogy of viscoelastic and elastic problems (elastic-viscoelastic analogy), a stationary solution of the action of mobile loads on a shell with a viscoelastic filler is obtained. It is shown that this principle makes it possible to generalize the class of problems obtained for the case of viscoelastic media. Since the viscoelastic filler has damping properties, the inversion integrals have no singularities on the real axis, and the elements of the determinants in integrals become complex since in this problem in the image space, the Lame coefficients are complex and depend on the speed of the load movement, as well as the Fourier transform parameter. Numerical results are obtained, and an analysis is made.

Analysis of Coupled Vibration Characteristics of Linear-Angular and Parameter Identification

Abstract A steady-state sinusoidal and distortion-free excitation source is very important for the accuracy and consistency of the calibration parameters of micro-electro-mechanical systems (MEMS) inertial sensors. To solve the problem that the current MEMS inertial measurement unit (IMU) calibration device is unable to reproduce the spatial motion of linear and angular vibration coupling, research topics on the coupling vibration characteristics and parameter identification for an electromagnetic linear-angular vibration exciter are proposed. This research paper used Ampere’s law and Lorentz force to establish the analytical expressions for the electromagnetic force and electromagnetic torque of the electromagnetic linear-angular vibration exciter. Then, the main purpose of this paper is to establish uniaxial and coupled vibration electromechanical analogy models containing mechanical parameters based on the admittance-type electromechanical analogy principle, and the parameter identification model is also obtained by combining the impedance formula with the additional mass method. Finally, the validity of the coupling vibration characteristics and the parameter identification model are verified by the frequency response simulation and the additional mass method, and the relative error of each parameter identification is within 5% in this paper.

Mutable Collagenous Tissue: A Concept Generator for Biomimetic Materials and Devices.

Echinoderms (starfish, sea-urchins and their close relations) possess a unique type of collagenous tissue that is innervated by the motor nervous system and whose mechanical properties, such as tensile strength and elastic stiffness, can be altered in a time frame of seconds. Intensive research on echinoderm 'mutable collagenous tissue' (MCT) began over 50 years ago, and over 20 years ago, MCT first inspired a biomimetic design. MCT, and sea-cucumber dermis in particular, is now a major source of ideas for the development of new mechanically adaptable materials and devices with applications in diverse areas including biomedical science, chemical engineering and robotics. In this review, after an up-to-date account of present knowledge of the structural, physiological and molecular adaptations of MCT and the mechanisms responsible for its variable tensile properties, we focus on MCT as a concept generator surveying biomimetic systems inspired by MCT biology, showing that these include both bio-derived developments (same function, analogous operating principles) and technology-derived developments (same function, different operating principles), and suggest a strategy for the further exploitation of this promising biological resource.

ИСПОЛЬЗОВАНИЕ ЭКСТРАКТА КОРЫ ЛИСТВЕННИЦЫ В КОРМЛЕНИИ СВИНЕЙ

The article presents materials from research on the use of Dahurian larch bark extract in the nutrition of weaned piglets, as an activation of metabolic processes, increasing pathogenetic resistance and preventing diarrhea. The studies were carried out on the pig farm of the collective farm in Kaluga region. on two groups of large white x landrace crossbred piglets during the growing period after weaning until placement for fattening lasting 70 days. Based on the principle of analogues, two groups of weaned piglets were formed: control and experimental. Piglets in the control group received standard complete feed. The piglets of the experimental group received larch bark extract powder, 4 g per head per day, as part of their general diet. The use of larch bark extract in feeding piglets contributed to an increase in the body's adaptive capacity, pathogenetic resistance and correction of metabolic processes, which ensured a higher realization of the genetic potential of pigs. Thus, in the blood serum of piglets receiving larch bark extract. the total protein content was 72.6 g/l, which was higher than that of the control by 5.7%, mainly due to the albumin fraction. In piglets of the experimental group, the serum creatinine content was 6.4% higher. They also significantly improved the functional state of the liver, as indicated by a twofold decrease in the bilirubin content in the blood serum (P<0.01). Changes in metabolism in piglets of the experimental group had a positive effect on the productivity and safety of the livestock. Thus, during the 70-day period of application of Daurian larch bark extract, the gross gain of piglets was 33.1 kg with an average daily gain of 473 g versus 28.1 kg and 416 g, respectively, in the control, which was 13.7% higher.

THE STUDY OF CLINICAL AND PHYSIOLOGICAL PARAMETERS OF ENZYMATIC AND IMMUNE ACTIVITY IN NEWBORN CALVES AFTER THE APPLICATION OF MODERN DOMESTIC BIOPREPARATION RIBOTAN

The aim of the work was to study the clinical and physiological parameters of enzymatic and immune activity in newborn calves after the application of the domestic biological product Ribotan to their mother cows 3-9 days before calving. The objects of the study were 20 clinically healthy pregnant cows of the Black-and-white breed, selected according to the principle of paired analogues, which were divided into 2 groups (control and experimental) of 10 animals each (n=10), and newborn calves received from them. The cows of the experimental group were injected Ribotan given as a single dose intramuscularly in a dose of 5 ml 3-9 days before calving. The cows of the control group were injected isotonic sodium chloride solution. On the 2nd day of life, calves showed a decrease in lactic acid content by 45%, as well as a lactate/pyruvate ratio by 17.9%. An increase in the activity of superoxide dismutase by 50% and a decrease in the level of malondialdehyde by 25.8% were noted. It was found that the application of the biopreparation led to an improvement in clinical and physiological parameters in calves, namely: a firm standing position was realized 11.2 minutes faster, the sucking reflex formed 13.6 minutes faster. The level of total serum immunoglobulins increased by 63%. A higher level of colostral immunity caused a 2-3 – fold decrease in the incidence of omphalitis and gastrointestinal disorders in calves.

Effect of probiotics on height and weight parameters of young cattle

The main direction of agriculture is the search for effective methods of production to provide the population with the provision and to ensure the food independence of the Russian Federation. The purpose of this study was to determine the effect of feed yeast produced in Russia and abroad on the growth of calves up to six months of age. The scientific and production experiment was carried out on the dairy farm of "Gigant" Agricultural Production Cooperative Collective Farm of the Stavropol Territory. Four groups of ten heads of black-and-white calves were formed according to the principle of analogues. The animals were ten days old. Together with the main diet the calves of the 1st experimental group received I-SAK1026 drug in the amount of 11 g per animal per day, the animals of the second experimental group were fed with "Levisil SC+" drug in the amount of 5 g per animal per day, and the calves of the third experimental group received "Optisaf" drug in the amount of 15 g per animal per day. Changes of linear measurements of growth rate with age were different. The animals of the third experimental group had an advantage in most of the measurements. Compared to the control, they showed more significant results. Based on the results of the study, the following was established. Calves of the third experimental group that received "Optisaf" probiotic were characterized by more significant activity of metabolic processes. The calves of this group were ahead of the control calves in terms of development and growth.

Evaluation of the quality of cow’s milk when using a mineral feed additive

Optimal cow feeding is the basis for successful dairy production, since feed costs can be up to half the cost of milk. An effective feeding program should achieve several goals: planned milk productivity, increased consumption of dry matter and improved functioning of the rumen microflora. Feed additives that affect the animal’s body play an important role in the diet, which is expressed in an increase in the average daily weight gain, a decrease in conversion rates and an improvement in metabolic processes. However, it is important to remember that additives alone cannot guarantee high productivity or economic benefits of dairy production. The purpose of this study was to study the effect of the multicomponent feed additive “Felucene” on the hygienic quality and safety of cow’s milk. The experiment was carried out in an educational and experimental farm, where, according to the principle of analogues, two groups of dairy cows of 40 heads each were formed. Both groups received the basic diet adopted by the farm, but the first group additionally received “Felucene” at the rate of 5 g per 1 kg of body weight. The analysis of milk composition and productivity was carried out on the 10th, 30th, 60th and 90th days of the study. The use of Felucene led to a 10% increase in dairy productivity of cows and improved milk quality characteristics: the mass fraction of fat increased by 0.09%, protein — by 0.20%, lactose — by 0.18%. The number of fat globules increased by 22%, and the content of the casein fraction increased by 10%. At the same time, the volume of milk corresponding to Class I in rennet fermentation and thermal stability increased by 18% and 17%, respectively.

Changes in live weight and protein parameters of blood in growing heifers and steers up to the age of 13 months

The studies were conducted on bulls and heifers of Holsteinized black-breed. Two groups of 10 animals were formed in each group according to the analogy principle. In the first group, there were heifers and in the second group, there were steers. Feeding and growing conditions were the same. Blood for biochemical studies was taken at 1,3,6,9,12 and at 13 months of age. The live weight of the heifers and steers was monitored at the same time and we calculated the average daily gain. Total protein and albumin were determined by the colorimetric method. The number of globulins and the value of protein coefficient (albumin/globulins) were calculated by the calculation method. With increasing age of experimental animals, the level of total blood protein gradually increased. Thus, in heifers the concentration of total protein by 13 months of age increased by 9.3 g/l and amounted to 70.1±0.9 g/l. In steers, the increase was 11.3 g/l and amounted to 72.0±1.1 g/l. Comparing the indices of total protein between experimental animals it was found that during the experiment the level of total protein in blood was not significantly higher in steers. The amount of albumin in heifers from 1 to 13 months of age increased by 9.8 g/l, and in steers by 12.3 g/l. In all periods of the experiment, the level of albumin was higher in steers in relation to heifers. The level of globulins from 1 to 13 months of age in heifers and steers changed irregularly. There were no differences in this index between heifers and steers. The value of protein index increased with increasing age of heifers and steers. The live weight of the heifers at 13 months of age was 353.0±1.7 kg, and of the steers 377.7±2.1 kg.

The European Parliament Against the Background of the Rule of Law and the Standards of a Parliamentary System: Selected Issues

The aim of this study is to show the legal status and mechanism of action of the European Parliament against the background of classical standards of the rule of law in a democratic system. This study shows the extent of the deviation of the European Parliament from these standards and highlights its special features by using historical-, theoretical-, and dogmatic-legal methods. This helps to understand what parliamentarism is built into the present concept of the rule of law, and what distinguishes it from the classically understood assumptions of a parliamentary system. Specifically, this study comprises three key issues: the nature of the subject that equips the Parliament with democratic legitimacy, the way it is situated in the mechanism of power or, finally, the extent to which it is bound by existing legal norms. This research perspective is, of course, limited in nature and deals with selected issues. The crux of the study makes the reader aware that at the level of the European Union a new type of parliament and, consequently, a new type of parliamentarism has developed, and the rule of law applicable here is clearly different from the analogous principle found in traditional states.

Modeling of dynamic modes of a generalized pumping station with an asynchronous electric drive of centrifugal pumps

Transportation of large volumes of liquid to distribution pipelines is provided by transit facilities - main pipelines and pumping stations, which consume significant amounts of electricity and are of strategic importance. The requirements for continuity, reliability, safety, fault finding, and diagnosis of existing, as well as requirements for the design of new strategic objects, are usually regulated by national legislation. The possibility of conducting physical experiments to analyze the modes of operation of such complexes is significantly limited by the inadmissibility of interrupting their functioning, as well as technical and financial risks. The use of a hybrid model consisting of a digital model of the power equipment and a physical model of the control system makes it possible to solve this problem. In this work, attention is focused on the digital model of power equipment. Based on the system approach and the principle of electrohydrodynamic analogy, a formalized mathematical model of the generalized system of asynchronous centrifugal pump units of a multi-unit pumping station with asynchronous electric drive of centrifugal pumps was created. The use of the principle of electrohydraulic analogy made it possible to apply the basic principles of the theory of electric circuits to form the equations of the hydraulic subsystem. The achieved formalization makes it possible to automate the formation of equations to obtain a model of an object of a specific configuration. The use of pump parameters in the model, which depend on the geometry of the internal elements, the speed of the impeller, and the physical properties of the liquid, makes it possible to investigate the impact of emergency and operational deviations of the equipment characteristics on the operating modes both at the level of individual modules and at the level of the pumping station as a whole. The obtained mathematical model was verified by adapting it to the pumping station of the given configuration. A computer simulation of several operational and emergency modes of operation of a pumping station with four hydraulically connected pumps was carried out. The scope of use and ways of improving the developed model are proposed, as well as the direction of further research

Сравнительная оценка мясной продуктивности молодняка овец при различных способах откорма

Purpose. Comparative analysis of meat productivity of rams of the Edilbaev breed during their grazing and fattening. Materials and Мethods. Scientific and production experience was carried out in the peasant farm Abdulkhalikov M.A. (Svetloyarsky district, Volgograd region) on two groups of rams of Edilbaev breed. The total number of animals participating in the experiment is 40. The formation of experimental groups was carried out according to the principle of analogues according to the methodology of A.I. Ovsyannikov (1976). The duration of the main experimental period was 120 days. The dynamics of live weight of rams was determined by measuring this indicator in each animal in the morning, before feeding, at the age of 4, 6 and 8 months. The rams were slaughtered (3 heads from each group) when the animals reached the age of 8 months. When studying meat productivity, we took into account: the weight of animals after fasting, the weight of the chilled carcass, the yield of the carcass, the weight and yield of internal fat, the fat tail weight and the yield of fat tail, slaughter weight, slaughter yield. All digital material obtained during the research was processed using statistical methods and Microsoft Excel software and determination Student-Fisher's reliability criterion of the difference. Results. Data on the dynamics of live weight at the age of 8 months indicate that the average live weight of fattening rams was 55.20 kg versus 50.80 kg for their peers in grazing. The difference in favor of fattening rams was 4.40 kg or 8.66% and was significant. Their superiority in absolute and average daily growth was 3.70 kg and 30.8 g, respectively. Over a period of 4 to 8 months, i.e. over 120 days of research, the average daily gain of fattening rams was 185.0 g versus 154.2 g for grazing rams of the same age. Fattening animals were superior to their peers in other slaughter indicators: in carcass weight - by 1.96 kg or 3.6% (P≤0.01), in internal fat weight - by 0.20 kg or 17.24 % (P≤0.01), in fat tail weight – by 0.60 kg or 18.30% (P≤0.05), by slaughter weight – by 3.93 kg or 14.41% (P≤0.01). At the same time, the slaughter yield for fattening rams was 58.10%, which is 1.90% higher than for grazing animals. According to morphological indicators, fattening rams are superior to their peers in fattening in terms of pulp weight by 2.08 kg or 12.17%. There was no significant difference in the mass of bone and connective tissue between animals of different groups. According to the meatiness index, grazing rams were inferior to their peers by 0.43 absolute values. Conclusion. Intensive fattening of young sheep of Edilbayev breed is a more effective method of fattening compared to grazing. The level of profitability of mutton production for fattening rams was 36.16% versus 13.47% for grazing rams of the same age. The difference in favor of fattening rams was 22.69%.

Theoretical research on the application of impedance calculation in the design of high-intensity low-frequency acoustic generator

The impedance matching is essential in producing high-intensity acoustic waves. This paper studies the impedance calculation methods of modulators and double-chamber Helmholtz resonators based on fluid mechanics, aeroacoustics, and electro-acoustic analogy principles. The results: ① The impedance expression of the resonators is derived. ② The impedance variation law of the chamber volume, the stator size, the air supply pressure, the air supply flow, and the working frequency is calculated. ③ The impedance-matching design scheme of the two-chamber Helmholtz low frequency and high acoustic intensity generator is given. Based on the experimental results of the high acoustic intensity generating device that the author has manufactured in the closed space, the correctness of the impedance calculation and matching design scheme in this paper is verified. This method has guiding significance for the design of high-intensity acoustic generating devices in confined space.

Acute toxicity of zinc carbonate nanocrystals on white mice model

Zinc-based nanoparticles (NPs) are successfully used to meet the mineral needs of animals and poultry, capable of increasing the growth rate and the efficiency of their use of feed. Nanoparticles of zinc oxide are widely used, which are superior to conventional sources of zinc in terms of pharmacological activity and bioavailability, have a positive effect on productivity and antioxidant protection, and increase reproductive potential. However, a detailed investigation of their toxicological parameters showed the risks of their introduction into the body, as a result of which a large number of zinc oxide NPs were synthesized by the methods of “green chemistry”, the main drawback of which is a complex methodology and a high level of costs. We investigated the acute toxicity of a colloidal solution of zinc carbonate nanocrystals in a model of white mice. The experiment was conducted on 42 female non-linear white mice, 3–4 months old, with a live weight of 21–23 g, kept under optimal vivarium conditions. According to the principle of analogues, 6 experimental groups were formed: mice were injected with a colloidal solution of zinc carbonate nanoparticles in doses (by absolute weight of the drug) of 15,000.0; 20000.0; 25000.0; 30000; 35000.0 and 40000.0 mg/kg of body weight based on the absolute weight of the drug, which according to the active substance (zinc carbonate nanoparticles) was (37.5; 50.0; 62.5; 75.0; 87.5 and 100, 0 mg/kg of body weight), orally using an esophageal-gastric tube. Mice of the control group were injected with distilled water in a volume of 0.2 cm3 according to the same protocol. The clinical condition of the experimental animals was observed for 14 days, noting the appearance and development of clinical signs of poisoning, the time of death or recovery to the physiological norm. After the death (diagnostic slaughter) of the animals, a pathological autopsy was performed. Clinical observations showed that a single intragastric administration of the drug to mice of experimental groups 1-6 did not cause acute poisoning. The deaths of mice in all experimental groups were not observed during the 14-day observation period, as a result of which the LD50 indicator could not be calculated. At the same time, the maximum possible injected dose of the colloidal solution of zinc carbonate nanoparticles (by absolute weight) was 40,000.0 mg/kg of body weight (100.0 mg/kg by active substance), which allows the drug to be assigned to the VI class of toxicity – substances are relatively harmless (LD50 > 15000.0 mg/kg of body weight), and according to the degree of danger up to IV class – low-hazardous substances (LD50 > 5000.0 mg/kg of body weight).