bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Different Concentrations of Melatonin on the Time-course of Nitriteâ€“induced Oxidation of Hemoglobin: In vitro Study
Authors: A.Hussain Saad , M. Mohammed Shaima , T. Numan Intesar , I. Abdulwahhab Ihab
Published: March 2022

Melatonin is a potent scavenger of reactive oxygen species or free radicals like superoxide and hydroxyl radicals. The oxidation of hemoglobin to methemoglobin (meth-Hb) by oxidizing compounds has been widely studied. The present work was designed to evaluate the ability of different concentrations of melatonin to inhibit nitriteâ€“induced oxidation of hemoglobin. Blood samples were obtained from apparently healthy individuals from which erythrocyte hemolysate was prepared. Different concentrations of melatonin (10-9-1.0 mg/ml) were incubated for 10 min with the hemolysate, then to the resultant mixture 1 ml of sodium nitrite (final concentration 0.6 mM) was added, and the formation of meth-Hb was measured by monitoring absorbance of light at 631 nm each min for 30 min. Control samples without melatonin were utilized for comparison. Nitrite caused rapid oxidation of hemoglobin to meth-Hb in control samples; in the presence of melatonin, the oxidation process was delayed in a doseâ€“dependent manner. The effect of melatonin on the time course of nitrite-induced oxidation of Hb showed that melatonin has a protective effect initiated early after addition along with nitrite. Melatonin also affect the time required for the formation of meth-Hb, the   time required to convert 50% of the available Hb to meth-Hb was 4 min in the absence of melatonin, and became  17, 22, 26, 30, 114 and 383  min with increasing melatonin concentrations (10-9, 10-6, 0.001, 0.01, 0.1, and 1.0 mg/ml  respectively). In conclusion, melatonin in a concentration  and time dependent manner can protect Hb from oxidation by nitrite; melatonin delays the onset of autocatalytic stage and the protective effect extended over long period of time.

Key words: melatonin, erythrocytes oxidation
ONTOGENETIC AGE AND INOCULATION METHODS FOR THE IN VITRO ESTABLISHMENT OF Eucalyptus pilularis Smith
Authors: Martins Avelar Maria Lopes , Moscardini Bruno Alves , Santana Costa Souza Denys Matheus , Vaz Molinari Letícia , Santos Gonçalves Douglas , Tannure Faria Júlio Cezar , Brondani Gilvano Ebling
Published: March 2022

We aimed to evaluate the in vitro establishment of nodal segments of Eucalyptus pilularis Smith considering two origins of tissues (Or1 - epicormic shoots collected from pruned branches of selected adult trees; Or2 - shoots collected from seminal mini-stumps) and four inoculation methods (Me1 - culture medium supplemented with 0.5 g L-1 activated charcoal; Me2 - culture medium supplemented with 800 mg L-1 PVP30; Me3 - exposure to light for 30 days; Me4 - exposure to dark for 7 days). At 30 days after the in vitro inoculation of tissues, there was no establishment of tissues from epicormic shoots (Or1). Or2 resulted in lower percentages of tissue oxidation and contamination by microorganisms, in addition to having presented establishment and formation of shoots. Me1 resulted in a lower mean tissue oxidation, although it differed statistically only from Me4. An origin of the tissues of ontogenetic age was a determining factor for the successful in vitro establishment of E. pilularis. The use of the Or2 origin and the Me1, Me2, and Me3 methods are recommended to reduce phenolic oxidation of tissues in the in vitro establishment.
Keywords: antioxidant agents; exposure to light; epicormic shoots; tissue oxidation.
 
Idade ontogenética e métodos de inoculação para o estabelecimento in vitro de Eucalyptus pilularis Smith
 
RESUMO: Objetivou-se avaliar o estabelecimento in vitro de segmentos nodais de Eucalyptus pilularis considerando duas origens de tecidos (Or1 - brotos epicórmicos coletados em galhos podados de matrizes adultas e Or2 - brotos coletados de minicepas seminais) e quatro métodos de inoculação (Me1 - meio de cultura suplementado com 0,5 g L-1 de carvão ativado, Me2 - meio de cultura suplementado com 800 mg L-1 de PVP30, Me3 - exposição à luminosidade por trinta dias e Me4 - exposição em ambiente com ausência de luminosidade por sete dias). Aos 30 dias após a inoculação in vitro dos tecidos, constatou-se que não houve estabelecimento de tecidos oriundos da Or1. A utilização de segmentos nodais provenientes da Or2 resultou em menores percentuais de oxidação e de contaminação por microrganismos, além de ter apresentado estabelecimento e emissão de brotos. O uso do Me1 resultou em menor média de oxidação, embora tenha diferido estatisticamente somente do Me4. A origem dos tecidos associada à idade ontogenética foi um fator determinante para o sucesso do estabelecimento in vitro de E. pilularis. Recomenda-se a utilização da Or2 e dos métodos Me1, Me2 e Me3 a fim de reduzir a oxidação fenólica dos tecidos durante o estabelecimento in vitro.
Palavras-chave: agentes antioxidantes; exposição à luminosidade; brotos epicórmicos; oxidação de tecidos.
Rationale of the dielectrometric method of definition of lubricant oils' tribological characteristics' changes
Authors: Shostakivskyi I. I. , Kharun V. R.
Published: March 2022

The article demonstrates the contradiction of generally accepted methods of research of lubricants tribological properties on the example of spent oil studies and critically considers the possibility of using the obtained results as criteria for assessing the serviceability of lubricating oils after a certain service life. In particular, regulatory parameters such as viscosity, flash point, acid value and insoluble sludge content were considered. Viscosity, in particular, was assessed by the Heppler’s and the Ostwald’s methods. As a result, it was found that the first of these methods shows lower values. Similar ambiguity is demonstrated by normative methods for determining the flash point in open and closed crucibles, determining the acid number by potentiometric or calorimetric titration of an oil sample dissolved in various solvents and determining the sludge content by extraction with n-pentane, n-heptane and extraction benzene. As it turned out, the results obtained by different methods are impossible to compare. The analysis of the obtained data also confirms the opinion that the indicators determined in the laboratory have no practical application, because they do not correlate with the real operating conditions of the oil. Such laboratory studies can only be used to compare two or more samples of lubricants. As an objective criterion that would reflect the interaction of the components of lubricating oils and friction units during operation and could serve as an indicator of the degree of aging of the oil, the author proposed to use the dielectric constant in an alternating electric field. These first research results show that changes in dielectric constant as a function of service life can be considered an indicator of the degree of aging of the oil, and the results allow us to estimate the concentration of sludge and mechanical contaminants in oils. However, given the multicomponent nature of modern oils and the influence of other factors on the dielectric penetration of the material, the results obtained should be considered only preliminary and those that require further refinement and processing.
Research of technology of parameters of manufacturing of the reinforced teeth of cones of drill bits
Authors: Shuliar I. O. , Kustov V. V. , Borushchak L. O. , Virstiuk A. B.
Published: March 2022

The increase in oil and gas drilling is closely linked to the use of high-performance, reliable and durable cone drill bits equipped with solid teeth or plug-in, reinforced wear-resistant materials. The decisive factor influencing the technical and economic efficiency of the process of drilling rocks, where oil and gas deposits occur, is the wear resistance of rock-destroying elements of chisels, made in the form of plug-in teeth and made together with the cone body. In this work, based on the results of drill bits design and manufacturing technologies, cones equipped with plug-in teeth formed by centrifugal reinforcement by hard alloys with rotation around two mutually perpendicular axes are selected for evaluation. The research was conducted on the developed stand. According to the results of experiments, a mathematical model was obtained that describes the influence of technological factors on the optimization parameter - the amount of tooth wear. As factors influencing the efficiency of the use of reinforced teeth were taken: Х1 - pouring temperature of steel, 0С; Х2 - the amount of introduced hard alloy, g; Х3 - frequency of rotation of the mold around the vertical axis, min-1; Х4 - the frequency of rotation of the mold around the horizontal axis, min-1. Their basic level and limits of variation of the upper and lower are established. The full factorial experiment 24 was used in the work. The plan of the experiment was made. In accordance with the selected plan, 16 active experiments were performed, and each experiment was repeated three times. Next, a mathematical model and a regression equation describing it are constructed. The degree of influence of process factors on the amount of abrasive wear of teeth and their optimal values is established.
Use of complex action to prevent and liquidation of asfalt, resin and paraffin deposits in the trunk of the well
Authors: Kopey I. B. , Serediuk V. D. , Demianchuk Ya. M. , Lialiuk M. Ya.
Published: March 2022

The purpose of article is development of technology and selection of the necessary equipment and chemical materials for fight against asfalt, resin and paraffin deposits. The way of prevention and elimination of deposits of paraffin and asphaltic substances on the borehole equipment of oil wells by complex effect of chemical reagents and thermal heating of a zone of adjournment is offered. It is specified problems of thermodynamic changes of rather phase condition of a stream and their account at establishment of technological operating modes of wells and use of new effective chemical reagent is proved. The choice of chemical reagent for prevention of adjournment of paraffin, pitches and asphaltenes for each field is individual. Even on certain wells within one field the selection is carried out after studying conditions of adjournment and their physical and chemical structure that causes a large amount of reagents and technologies which are recommended for using on fields of Ukraine. As a result of researches the established efficiency of use of Twin-80 inhibitor which mechanism of action is in what in the presence of Twin-80 water contacts to microcrystals of paraffin and salts moistens them, prevents their adhesion and adjournment on walls of pipes. The technology of cleaning of the equipment consists in constant or periodic supply of reagents to the well. The experimental copy of the borehole electric heater by means of which there is a cleaning of a column of lifting pipes by the principle of dot and plane heating is developed and manufactured. As a result of use of technology of complex action for prevention and elimination of asfalt, resin and paraffin deposits the technical result – the accelerated cleaning of a trunk of the well and the borehole equipment, increase in efficiency of its operation and economy of the electric power turns out.
Determination of the characteristics of a jet pump during its asymmetric rotation in a well
Authors: Panevnyk D. O.
Published: March 2022

The hydraulic model of low-pressure jet pump working process for conditions of its asymmetric rotation is proposed on the basis of law of conservation of liquid momentum of parallel mixed potential flows with linear distribution of tangential velocities and radial displacement relative to borehole axis. In the process of derivation of the equation of pressure characteristic of low pressure jet pump at its asymmetrical rotation in a borehole the law of conservation of flow energy in the form of Bernoulli's equation and the law of continuity conservation of mixed currents have been used. To characterize uneven distribution of kinematic parameters in the mixing chamber of jet pump, the unevenness coefficient in the form of ratio of average and axial circumferential velocities of mixed flows is introduced. Flow rates of working, ejected and mixed streams are determined by integration of the adopted velocity profiles in the inlet and outlet sections of the mixing chamber of the jet pump. The developed hydraulic model allowed obtaining a dimensionless relative form of equation for determining the additional head of the jet pump caused by its asymmetric rotation in the borehole. The magnitude of the additional dynamic head increases as the peripheral velocity increases and the operating flow rate decreases. The total head produced by the jet pump is calculated by summing the additional head and the head obtained for the stationary ejector system. The rotation of the borehole ejection system causes the head and the efficiency of the jet pump to increase. The proposed hydraulic model can be used to improve the efficiency of jet pump mode prediction as a part of assemblies for drilling and bottomhole cleaning.
Nasal type extranodal natural killer/T-cell lymphomaassociated hemophagocytic lymphohistiocytosis: A Case report and literature review
Authors:   Department of Hematology, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China, Liu Xuelin , Wei Liqiang ,   Department of Hematology, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China, Yang Jing ,   Department of Hematology, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China., Ye Jin Ye ,   Department of Hematology, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China, Wang Liang ,   Department of Hematology, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
Published: March 2022

Hemophagocytic lymphohistiocytosis (HLH) is a clinical syndrome in which a large number of inflammatory cytokines, such as IL-6, TNF-α, and sCD25, are released into the blood circulation due to cytotoxic killing cells and dysfunction of natural killer (NK) cells. HLH can be induced by various infections, cancer, or hereditary disorders. HLH is usually fatal due to severe cytopenia and multiple organ failure. Nasal type extranodal natural killer/T-cell lymphoma (ENKTCL) is an aggressive non-Hodgkin’s lymphoma that is closely related to Epstein-Barr virus. ENKTCL can be complicated by HLH at initial diagnosis and recurrence. However, the optimal treatment strategies for ENKTCL-associated HLH are not well defined. Here, we report a case of ENKTCL-associated HLH that was successfully treated with liposomal doxorubicin, etoposide, methylprednisolone, and pegaspargase (DEPL regimen), followed by immunotherapy. This report aims to contribute to improved recognition, diagnosis, and treatment of lymphoma-associated HLH. Keywords: Hemophagocytic lymphohistiocytosis, extranodal natural killer/T-cell lymphoma, liposomal doxorubicin, pegaspargase, lymphoma-associated HLH
Fear-Inducing Coronary Spasm in an Asthmatic Patient with Right Bundle Branch Block; Oxygen Reversal and Reassurance
Authors: Hassanain Elsayed Yasser Mohammed
Published: March 2022

Rationale: Fear is one of the most psychosomatic risk factors in clinical medicine. Generally, ischemic cardiovascular events are strongly linked with psychological stress. Patient concerns: An elderly-aged housewife female asthmatic patient presented to the physician outpatient clinic for cardiovascular follow-up is getting coronary artery spasm after inducible fear. Diagnosis: Fear-inducing coronary spasm in an asthmatic patient with right bundle branch block. Interventions; Electrocardiography, oxygenation, and echocardiography. Outcomes: Dramatic of both clinical and electrocardiographic improvement post-oxygenation had happened. Lessons: The fear may be an inducible factor for coronary artery spasm and cardiovascular events. It signifies the role of oxygenation in the reversal of coronary artery spasm and it is the future concept. The association of patient right bundle branch block in an asthmatic patient is reasonable. The presence of the patient’s relatives or friends during medical procedures may be a source of danger to the patient.
Mandibular AV Malformation: Life-Threatening Bleeding from the Mouth managed by Endovascular Intervention Complicated by Acute Ischemic Stroke on table. Case Report
Authors: Habib Mohammed , Hillis Mohammed , Almobayed Aghayed , Alhadad Mohanned , Alkhodari Khaled
Published: March 2022

Arteriovenous malformations (AVM) of mandibula are rare abnormal congenital vascular condition that can result in serious complications. Although, various treatment options have been advocated in the literature, there seems to be no complete consensus on a suitable treatment option in these cases. Here, we describe a case of mandibular AVM, who has presented with massive oral bleeding, treated successfully by embolization of the bilateral external carotid arteries and the left superior thyroid artery. During the procedure, the patient developed symptoms of acute ischemic stroke that was diagnosed and managed during the same session by endovascular techniques.
Atherosclerosis and Human Life Expectancy
Authors: Ermoshkin Vladimir Ivanovich
Published: March 2022

The relationship between a person's lifestyle and the degree of atherosclerosis is very important. Trying to find such a connection is the goal of many researchers. It is also the purpose of the author's work, a brief description of which is given in this review. Method: Study of information on the Internet, participation in medical conferences, participation (only for 2021) in 3 international webinars on atherosclerosis, publication of articles. Results: The importance of this issue for modern man is very great.
Decades of serve dyslipidemia without plaque formation in a caucasian female
Authors: E. Feeman William
Published: March 2022

Dyslipidemia is a well-known cause of atherothrombotic disease (ATD) The author presents an unusual case of a woman with severe dyslipidemia who was unable to tolerate any dyslipidemic medication combination for any length of time over the last 25 years and yet has a normal coronary artery CAT scan done for chest pain, which is presumed to be micro vascular angina.
Tips in Anesthetic Techniques in Hypertrophic Cardiomyopathy
Authors: Değirmenci Hüsnü , TAŞ Hakan Gökalp
Published: March 2022

Hypertrophic cardiomyopathy (HCM) is a common hereditary cardiomyopathy that affects up to 1 in 200 people in the general population [1,2] Patients with HCM usually have asymmetric or isolated areas of left ventricular hypertrophy >15 mm that aren't caused by anything else. The majority of patients have left ventricular outflow tract (LVOT) blockage at rest or with provocation owing to systolic anterior motion (SAM) of the mitral valve with mitral-ventricular septal contact. In addition, SAM causes mild to moderate mitral regurgitation (MR), which is usually oriented posteriorly [3, 4]. Up to 60% of HCM patients experience cardiac issues after surgery (myocardial infarction (MI), congestive heart failure (CHF), or both) [5]. We will discuss anesthetic technique selection during noncardiac surgery for individuals with a preoperative diagnosis of HCM and provide some tips in this review.
The Arkansas Lincoln Project: Design of a Novel Interventional Model to Address Cardiovascular Health Disparities in Rural, Underserved Communities of the Arkansas Delta
Authors: W. Pursell Irion , W. Barnes Jessica , Massing Mark , Dugyala Sushma , Cottoms Naomi
Published: March 2022

Serious health-related disparities continue to disproportionately impact underserved, low-wealth, and minority communities driven by an entanglement of factors. Studies show cardiovascular disease (CVD) prevalence in rural areas is advancing with widespread consequences on the local economies, health care systems, and population. Previous efforts in healthcare and community-based systems to impact rural CVD and CVD-related outcomes have been mostly unsuccessful for various reasons. The Lincoln Project (TLP) in Arkansas was conceived in response to this serious unmet need and with historical shortcomings in mind. TLP adopts a novel community health worker-led neighborhood-based strategy, bridging the gap between social resources, health care services and the rural communities they serve with the goal of rebalancing CVD-based health equity in areas of Arkansas with the most severe health disparities.
Figury retoryczne w dyskursie perswazyjnym – konfrontacja na podstawie analizy reklam polskich, włoskich i francuskich
Authors: Dolata-Zaród Anna , Pastucha-Blin Agnieszka
Published: March 2022

The aim of the present article is to offer a comparative analysis of advertising discourse with regard to the presence and classification of rhetorical figures as an efficient strategy of persuasion. Short commercial texts extracted directly from trade offers of producers, sales companies and online shops, as well as advertisements published on websites and in on-line versions of magazines have been analyzed. Due to limited textual capabilities, we have decided to restrict the scope of the analysis to texts which promote cosmetic products, as well as those that advertise various beauty treatments as a means of improving the appearance and well-being of contemporary women. In order to fully demonstrate the comparative aspect of the study, we have analyzed advertisements of the same products (of commonly known brands) in three linguistic versions, Polish, Italian and French, thus indicating the differences and similarities stemming from the employment of rhetorical figures.
Rola powtórzeń w "Civilisation universelle et cultures nationales" Paula Ricœura
Authors: Bobowska-Nastarzewska Patrycja
Published: March 2022

This paper concerns the role of repetitions in Paul Ricoeur’s text entitled Universal Civilization and National Cultures (1961). The analysis aims to prove that the repetitions are a characteristic element of the philosopher’s style. In the analysis the author focuses on the repetitions in the connected and disconnected word order and on repetitions as figures of speech. Ricoeur repeats in his text words, expressions and grammatical constructions. A distinctive element of Ricoeur’s style is also the text structure, e.g., the text division into three parts, the so-called triad system.
"Poemat o zagładzie Lizbony" (1755) i "Kandyd" (1759) czyli Wolter wobec Leibniza
Authors: Niedziela Mateusz
Published: March 2022

This article deals with the ways Voltaire makes references in his texts to the philosophical thought of Leibniz. To achieve maximum coherence, this paper only discusses those writings by Voltaire that most directly refer to the Leibnizian issues. These are primarily Poem on the Lisbon Disaster and the philosophical tale Candide, or Optimism. The article critically examines various aspects of Leibniz’s philosophy, such as the theory of pre-established harmony and the concept of monads, and above all the notion of the best possible universe. Moreover, selected aspects of Voltaire’s and Leibniz’s thoughts are compared. For the purpose of consistent analysis, the article primarily focuses on those features in the German philosopher’s system that were particularly questioned by the author of Candide.
Obraz kaukaskich rzek w poezji Tadeusza Łady-Zabłockiego
Authors: Tarnowska Beata
Published: March 2022

This paper presents the image of Caucasian rivers in the poetry of Tadeusz Łada-Zabłocki (1811–1847), a tsarist exile to the Caucasus. Zabłocki’s poetic vision of the rivers that flow through the Caucasus Mountains (the Alazani, the Kura, the Samur, the Kodori, the Aragvi and the Terek) is clearly ambivalent. Unlike his domestic, Belarusian rivers – a symbol for familiarity and idyllic harmony with nature – they are perceived as rapid, wild and dangerous entities. Yet, they stand for both the dominion of death and the unbridled power of life.
Posesión de Tiempo Inmemorial (Possession of Time Immemorial)
Authors: Brangier Víctor , Lorca Mauricio
Published: March 2022

This study focuses on disputes between small and medium tenants, who sought to formalize old land rights. The context under study is Rengo Valley, Chile, between 1820 and 1830, where there was increasing pressure to clarify rights over possessions. The analysis of a sample of 31 trials showed the relevance of the judicial use of the figure Posesión de Tiempo Inmemorial (Possession of Time Immemorial). This was a resource derived from the value of possession in the Hispanic American agrarian legal culture, one that the litigants used strategically. This study’s findings provide new data on the use of socially valued legal figures in justice to defend possession, thus contributing to the discussion on the dispossession of peasants in contexts of proprietary formalization.
General Collective Intelligence as a Platform for Computational Social Systems
Authors: Williams Andy E
Published: March 2022

The emerging science of General Collective Intelligence or GCI defines the requirements for a hypothetical platform able to self-organize individuals in a self-sustaining way into massive networks of cooperation with the capacity to execute collective reasoning in a way that might exponentially increase the general problem-solving ability of the group. Some of these requirements of a GCI include the property of “dynamic decentralization”, without which any modeling, simulation, analysis or understanding of social systems from a quantitative and/or computational perspective are hypothesized to be centralized in a way that prevents them from being free of being constrained to be aligned with the individual interests of any powerful decision-makers involved in any of these processes. This paper explores why, as a consequence, building computational social systems on top of GCI is critical in ensuring that any class of problem can be solved where that class relates to the misalignment between the interests of influential individual decision-makers, and the outcomes that would be beneficial for the group.
Human-Centric Functional Modeling and Defining Metrics for the Function and Level of Consciousness
Authors: Williams Andy E
Published: March 2022

Human-Centric Functional Modeling provides a methodology for defining the properties of systems. This short paper explores its application to defining a representation of, and metrics for, both impaired consciousness as well as the heightened levels of consciousness sometimes referred to as “enlightenment” in various traditions.
Poblamiento y dinámica demográfica de San José del Álamo (Viesca) y los asentamientos de La Laguna (1731–1825)
Authors:   Universidad Autónoma de Coahuila, González Flores José
Published: March 2022

This text analyzes the population and demographic dynamics of San José del Alamo and its jurisdiction in the area known as La Laguna in the current southwest of the state of Coahuila. The Alamo Indian town arose when the colonization project of the Tlaxcalans of Parras was imposed on that of the powerful landowner Marquis de Aguayo. The first years were difficult but the population of La Laguna had moderate growth despite the constant incursions of enemy Indians. By 1825 the Alamo and nearby haciendas were already established and their demographic structure was similar to that of other consolidated settlements in the Mexican northeast.
INVESTIGATION ABOUT ELECTROMAGNETIC FIELD TOPOLOGY OF THE SPIRAL COIL FOR NQR DETECTOR OF EXPLOSIVE AND NARCOTIC SUBSTANCES
Authors: MOISIUK Oleksandr , SAMILA Andrii ,   Yuriy Fedkovych Chernivtsi National University
Published: March 2022

Given the increased likelihood of dangerous situations in Ukraine and abroad related to the intensification and scale of terrorist acts, it is important not only to quickly locate and eliminate the terrible consequences, but also to prevent, including prevent destabilizing factors. That is why remote detection of explosives and drugs is relevant and promising in the direction of strengthening the fight against terrorism and increasing national security. A promising method for detecting the vast majority of explosives and narcotics that contain nitrogen (14N) or chlorine atoms (35Cl, 37Cl) is the nuclear quadrupole resonance method. In the presence of a gradient of high-frequency field strength inside the sample in the process of forming the response signal is “blurring” the vector of the total spin magnetization, which leads to the expansion of the resonant signal and reduce its amplitude. Increasing the homogeneity of the high-frequency field is especially important for the detection of weak signals observed in the study of substances with a low natural prevalence of magnetoactive nuclei. The paper presents the results of research on the topology of the electromagnetic field strength of a helical coil designed for use as a transmitting and receiving antenna of a portable detector of explosives and drugs, the principle of which is based on the registration of 14N isotope signals by nuclear quadrupole resonance. To determine the topology of the electromagnetic field, a computational domain was created, which is a model of the physical structure of the spiral coil. The finite element method performed numerical simulations in COMSOL Multiphysics. The simulation was performed at a frequency of 3.4 MHz, which is close to the value of the detection frequency of the attenuation signal of free induction from sodium nitrite 3.41 MHz. The best results were shown by the model of the coil with five turns, internal radius of 25 mm, external radius of 225 mm. The obtained magnetic field diagrams indicate better resistance to radio frequency interference when working in a real experiment. Based on the data obtained during the simulation, a multilayer (Multislice) model of the electric field and the isosurface of the electromagnetic field of the studied model were created, which demonstrate the dynamics and density of the electromagnetic field around the coil. From the obtained graphical dependences it is possible to draw a conclusion about the normalized attenuation of the intensity of electric field radiation from the geometric center of the coil, which, in turn, makes it clear exactly how to place the sample.
DYNAMICS OF A CIRCULAR KNITTING MACHINE WITH A DEVICE OF REDUCTION OF DYNAMIC LOADS WITH TWIN SPRINGS
Authors: Kovalyov Yuri , Pleshko Sergey , Lopukhov Evgeny ,   Kyiv National University of Technologies and Design
Published: March 2022

The issue of improving the efficiency of circular knitting machines remains relevant, so the task of research is to develop a new design of circular knitting machine with a device to reduce dynamic loads with torsion springs, engineering method of choosing rational parameters of the device, and evaluate its efficiency. The aim of the work is to analyze the feasibility of using a device with torsion springs to reduce the dynamic loads in the drive of circular knitting machines, to develop a method for selecting rational parameters of the device and evaluate the effectiveness of its use. The article uses modern methods of the theory of dynamics of mechanical systems in order to assess the feasibility of using a device with a torsion spring to reduce the starting dynamic loads in the drive of machines. Based on the analysis of the dynamics of mechanical systems with elastic ties, an algorithm for calculating the dynamic loads that occur during the start of circular knitting machines, the calculated dynamic model of which is reduced to a three-mass dynamic model with an average leading mass. A new design of the device is proposed to reduce the dynamic loads that occur during the start of circular knitting machines. In contrast to the known devices, the proposed device is made in the form of two cylindrical torsion springs and bypass couplings, which increases its efficiency. The new design of the drive of the circular knitting machine with the device of reduction of dynamic loadings with torsion springs, a method of a choice of rational parameters of the device and results of an estimation of efficiency of its use are presented. A scientific novelty is the development of scientific bases and engineering methods for designing devices for reducing dynamic loads in the drive of knitting machines. The practical significance lies in the development of a new design of the device for reducing dynamic loads in the drive of circular knitting machines and an engineering method for selecting its rational parameters.
INFLUENCE OF COLOR OF THE IMAGE-TEST BACKGROUND ON THE TIME OF DETECTION BY THE HUMAN-OPERATOR OF THE OBJECT LOCATED ON IT, IN COMPUTER TRAINING SYSTEMS
Authors: Boichuk A. , Kaminsky R , Shakhovska N. , Khudoba B. ,   Lviv Polytechnic National University
Published: March 2022

The paper presents the results of an experimental study regarding the influence on the recognition time of an object of a given color, from the background color on which this object is randomly localized. The following factors were taken into account: background orientation, object localization sector, area of the site with the object, color of this area, and the complexity of the recognition itself. Eight young students agreed to take part in the experiment. The working hypothesis was whether the recognition time depends on the color of the background area on which the object of attention is located. The object of attention was a light gray image of the plane. The research results are presented in the tables of values of expert estimates of factors and diagrams of the scope – box plot diagrams. The homogeneity of the psychophysical characteristics of the recipients is represented by the result of cluster analysis using as signs of indicators of individual time series, multiple regression equations. The organization of the experiment was to provide the recipient on the monitor of a computer simulator sequence of test images with the appropriate characteristics. The analysis of the results showed that despite the differences in individual psychophysical characteristics, background-color influences the time of recognition of the object of attention. In general, the study showed that, despite some simplicity and primitiveness of the test image, we could confidently accept the assumption of the influence of background color on the time of search and detection of objects of attention. As the sets of scale diagrams show, each recipient perceives the color differently, and in this case, for some background colors, the difference between the recipients is quite small.
DIGESTIBILITY OF NUTRIENTS AND BROILER CHICKEN PRODUCTIVITY UNDER THE ACTION OF PROBIOTIC ENTERO-ACTIVE
Authors: Poberezhets J. , Kupchuk I. , Yaropud V. , Burlaka S. ,   Vinnytsia National Agrarian University
Published: March 2022

The probiotic “Entero-active”, due to the formation of lactic and acetic acids, creates an unfavourable pH environment for pathogenic microflora, stimulates the growth of intestinal normal flora, which has a positive effect on the composition of the microbiocenosis. In addition, probiotic microorganisms produce biologically active substances, enzymes and amino acids. The aim of the research was to investigate the digestion of feed nutrients by broiler chickens fed by the probiotic supplement Entero-active. Optimal doses of probiotic feeding are determined on the basis of obtained results. The influence of probiotic supplement on digestibility of feed nutrients, availability of amino acids and retention of mineral elements of mixed fodder is established. Tendencies of changes in productivity and safety of poultry under the effect of probiotic are revealed. The broiler chickens fed by additive Entero-active have increased the digestibility of dry matter by 2.4% (P <0.01), protein by 3.4% (P <0.001), fiber by 31.1% (P <0.001) and NFE by 4.0% (P <0.001) comparing with the control group. According to our research, the application of probiotic supplement Entero-active for the broilers’ feeding increases the availability of essential amino acids, i.e. lysine by 4.8%, histidine by 3.8%, arginine by 4.9%, threonine by 7.5%, valine by 4.1%, methionine by 2.6%, isoleucine by 7.6% compared with the control indicator. It was found the absorption of Ca, P, Mg, Mn, and increases respectively, by 23.5%, 6.9%, 12.2%, and by 33.1% under the action of probiotics. The Entero-active probiotic application in the diet of broiler chickens increases the pre-slaughter live weight by 16.7%, the weight of ungutted carcasses by 15.0% and gutted carcasses by 17.3%, feed costs per 1 kg increase by 12.9%, relative to control. Our studies have made it possible to identify certain patterns in the digestion of nutrients by poultry, depending on the different doses of probiotic Entero-active used in their diets.
ANALYSIS OF PEER-TO-PEER NETWORKS TRENDS
Authors: KUPERSHTEIN LEONID , KRENTSIN MYKHAILO ,   Vinnytsia National Technical University
Published: March 2022

The concept and nature of peer-to-peer networks are analyzed, a short history of their development is researched and presented. The first network of this type (Usenet), its features and prerequisites are described. Three types of peer-to-peer network architectures are considered – pure, federal and hybrid; advantages and disadvantages of each. The hybrid architecture is the most widely used today, as using a central server to connect nodes is a promising approach. Three generations of peer-to-peer networks are considered and their architectural features are presented. The first generation involved only file sharing, its feature was the use of a central server, which had information about which node contains which file. The second generation was characterized by the absence of a central server, but there was no indexing of nodes and data, which caused long delays in finding a node to connect. The third generation is more advanced, because it provides storage in each node of hash tables with information about other network members. The main advantages and disadvantages of peer-to-peer network architectures are investigated. A comparative analysis of peer-to-peer and multi-peer networks is performed. It is determined that it is more expedient to use decentralized networks in comparison with centralized ones, especially in cases where anonymity, confidentiality, fault tolerance and scalability are a priority. The most known directions of practical use of peer-to-peer networks are investigated. Today they are used in chat systems, banks, cryptocurrency systems, video communication systems. Decentralized systems are also used when working with digital wallets, because it makes online payments more effective.
ASSESSMENT OF THE QUALITY OF HIGHER EDUCATION INSTITUTION’S WEB RESOURCES INFORMATION CONTENT TAKING INTO ACCOUNT THE PARAMETERS WHICH CHARACTERIZE THE COMMUNICATIVE ACTIVITY EFFECTIVENESS
Authors: SHILINH Anna , KHOMYN Natalia ,   Lviv Polytechnic National University
Published: March 2022

The aim of the article is to study the web resources of a higher education institution as an effective means of communicating the activities of this HEI. The study is based on the choice of methods for assessing the quality of higher education institutions’ web resources information content, taking into account the parameters of the effectiveness of its communication. The article identifies the role of official web resources of higher education institutions in modern conditions (in particular, in the context of the Covid-19 pandemic). In this paper, the information content of web resources of higher education institutions is defined as an information product. It is established that high-quality information content is a necessary condition for effective communicative activity of a higher education institution in the virtual space. The article uses approaches to assessing the quality of higher education institutions web resources information content by assessing the quality of such information products as software. That is why their quality is determined by a set of indicators determined according to the ISO / IEC-25010 standard, taking into account the parameters of the effectiveness of communicative activities of higher education institutions in virtual space. As a result of research it is established that to assess the quality of the higher education institution’s web resources content, taking into account the parameters of the effectiveness of its communication, the appropriate characteristics / sub-characteristics of software quality in accordance with ISO / IEC-25010 standard. It is this approach that allowed us to practically assess the effectiveness of free resources of the higher education institution in communicating with consumers of educational services in cyberspace.
IMPROVEMENT OF SOFTWARE SYSTEMS FAULT TOLERANCE ENSURING ALGORITHMS
Authors: ANTICH DMYTRO , RADELCHUK GALINA ,   Khmelnytskyi National University
Published: March 2022

The study investigates the concepts of fault tolerance and methods of system responses to failures. The study is based on the research of modern resiliency patterns and common approaches of reaction to failures. During the research, the common unresolved issues with modern resiliency and fault tolerance approaches were defined. The study improved the method of the system response to failures by designing a comprehensive solution that includes refinement and expansion of classical patterns of fault tolerance as a proposal to resolve common problems. The new solution of fault tolerance is based on the combination of basic monitoring approaches, load balancing approaches, circuit breaker pattern, and re-designing of the sharding pattern to be applicable not only for databases but also for modern applications. The new solution is based on an automatic decision-making expert system, which based on anonymous data saved by the monitoring layer decides the root cause of the issue and validates which scenario is applicable for the current situation. Based on the decision system can either enable a user and load balancing approaches by isolating harmful users using improved sharding and load-balancing solutions or enable a circuit breaker to temporarily disable the faulty features. The new method of resiliency is supposed to prevent and reduce more errors compared to the existing solutions in the domain of fault tolerance and resiliency, thus the efficiency of the new approach is higher. The expediency and urgency of designing a new method of fault tolerance are substantiated by expressing the importance of resolving existing problems. Improved methods of automatic response and failure prevention, which allowed to reduce the number of errors that occur in the system compared to existing solutions in resiliency and fault tolerance.
FEATURES OF APPLICATION OF E-LEARNING COURSE IN THE STUDY OF CHEMICAL DISCIPLINES
Authors: KHYZHAN O. , NESTEROVA K. ,   National University of Life and Environmental Sciences of Ukraine, KHYZHAN O. ,   L.M. Litvinenko Institute of Physical Organic and Coal Chemistry, National Academy of Sciences of Ukraine
Published: March 2022

The paper presents the methodology of developing a distance learning course in organic chemistry for students majoring in “Biotechnology and Bioengineering” in the Moodle shell. An e-learning course is offered to organize distance learning for students. Based on the use of Moodle modules, there is a system of learning and control over it, which is focused on the organization of interaction between teacher and students and can be effectively used for the organization of blended learning and distance learning. With the help of such a system the student can remotely, get acquainted with the study material, perform tasks and send the results of their performance for verification, pass electronic testing in the mode of self-control and control. In the period of growing relevance of distance learning, the use of such elements as video and audio clips, animations, illustrated graphics and diagrams, interactive educational games, links to Internet resources, simulations and various tools for communication, collaboration and messaging are appropriate. It includes a course business card, general information, 3 content modules and a control unit. The course contains different types of elements: lectures, presentations, glossary, news forum, tests, tasks. The task of the course is to organize distance and independent work of students and perform tests. Laboratory works are presented using video materials. The developed electronic course in the discipline is constantly evolving and focused on the needs of students with the ability to modify the presentation of the material. The course in organic chemistry for distance learning activates the independent work of students. The use of e-course in the educational process allows you to write and test in a remote format.
CURRENT ISSUES OF MONITORING THE CHLORITE AND CHLORITE CONTENT IN DRINKING WATER AFTER OXIDATION DISINFECTION
Authors:   Odessa National Medical University, MOKIENKO A. , SPASIONOVA L. ,   National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, BONDARCHUK Yu. ,   National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”
Published: March 2022

The use of oxidants (chlorine, chlorine dioxide and ozone) is a priority way of safe water supply. However, their use involves control of the formation, determination and normalization of chlorites and chlorates as by-products of disinfection. The aim of the work was to characterize the topical issues of monitoring the content of chlorites and chlorates in drinking water after disinfection with oxidants. Research methods included bibliometric and analytical. The results are as follows. The analysis of foreign and domestic normative documents testifies to the need to harmonize the current DSanPiN 2.2.4-171-10 “Hygienic requirements for drinking water suitable for human consumption” regarding the standardization of chlorites and chlorates in accordance with international requirements. It should be noted that these values, namely the normative values ​​for chlorites and chlorates at the level of 0.7 and 0.7 mg / l, respectively, were included in the latest version of the above-mentioned normative document DSanPiN 2.2.4-171-20. An analysis of the experience gained in Europe (European federation of national associations of water services) shows that the main source of chlorite and chlorate formation is not chlorine dioxide, as previously thought, but sodium hypochlorite. According to the WHO, chlorate is a typical by-product of disinfection in the treatment of water with oxidants (sodium hypochlorite, chloramines, chlorine dioxide, ozone). Currently, research on the development of technological principles for minimizing the content of chlorites and chlorates as by-products of water disinfection by oxidants in Ukraine has not been conducted. The above necessitates the implementation of the following tasks: generalization of research results of chlorite content in drinking water from centralized drinking water supply systems, where chlorine dioxide is used; development, testing and implementation of the method of determination of chlorates in drinking water; determination of the content of chlorites and chlorates in the finished sodium hypochlorite, which is supplied to water utilities, depending on the shelf life; monitoring the content of chlorites and chlorates in drinking water of settlements where sodium hypochlorite is used in the process of water treatment; determination of chlorate content in chlorinated tap water after its treatment with ozone; substantiation of optimal modes of water treatment with oxidants to minimize the content of chlorites and chlorates in drinking water from the water distribution network; development of technological principles for minimizing the content of chlorites and chlorates in drinking water after disinfection with oxidants.