bluuebunny/crossref_metadata_2025 huggingface dataset:
DNA in Motion
Authors: Johnson David A.
Published: September 2021

Students often struggle to understand the full implications of some basic chemical concepts of DNA structure and function, especially how DNA’s directionality and antiparallel nature determine key functional features of replication and molecular recombination. Visualizing the complexities of these processes requires a working knowledge of how DNA’s nucleotides are assembled and how these components interact. This article describes a simple activity that can be used to visualize how nucleotides join together, how base pairs form, and, most importantly, how the active processes of replication and recombination are related to DNA chemistry. In this activity, students model DNA structure, with each student representing a single nucleotide, then join together to form a polynucleotide with 5′ to 3′ directionality. Two chains then pair to form the antiparallel DNA duplex. The activity not only illustrates the basic chemistry of DNA but also allows students to participate in active modeling of leading-strand and lagging-strand replication and in the formation of the Holliday junction molecule, the basic intermediate of recombination events including crossing over and gene conversion. The demonstrations can be videotaped from above to make a permanent copy of these events for teaching and study purposes. Example illustrations and links to videos are included.
Linking Genetics, Microbiology & Molecular Biology Courses to Provide Research Experiences in Undergraduate Biology
Authors: Lucas Bethany , Nichols Gena , Boeck Max
Published: September 2021

Course-based undergraduate research experiences (CUREs) can have benefits for many students, especially those who lack access to traditional apprenticeships for research. As part of an effort to create more opportunities for students to have access to primary research and move away from traditional cookie-cutter labs, we have created a multicourse CURE spanning three undergraduate teaching labs in which students can pick and choose to take any of the courses that most interest them. This CURE explores the essential understanding of the emergence of antibiotic-resistant bacteria as well as high-throughput sequencing and mutagenesis screens. These low-cost modular labs are designed to be flexible and integrated into any single teaching lab to increase exposure to both fundamental lab skills and primary research.
Chronic hyponatremia based on maxillary sinus mass
Authors: Tudor Darija , Kolombo Iva , Tot Ana , Cikojevic Drasko , Simunovic Marko , Skrabic Veselin
Published: September 2021

This is a case report of a child with chronic hyponatremia due to the syndrome of inappropriate antidiuretic hormone secretion (SIADH) as a paraneoplastic manifestation of olfactory neuroblastoma (OFN). We hereby report a clinical presentation as well as a pragmatic approach to one of the most common electrolytic disorders in the pediatric population and have emphasized the necessity of involving the sinonasal area in the diagnostic procedure while evaluating possible causes of SIADH. This report indicates that the chronicity of the process along with the gradual onset of hyponatremia occurrence is responsible for the lack of neurological symptoms at the moment of disease presentation.

Learning points

Hyponatremia is not infrequently attributed to SIADH.

Paraneoplastic syndromes are uncommon but they should be considered in the differential diagnosis of pediatric SIADH.

Chronic insidious hyponatremia may not be associated with clear neurological symptoms despite its severity.
Association between circulating insulin-like growth factor 1 and risk of all-cause and cause-specific mortality
Authors: Xie Yu , Huang Changzhi , Zhu Xingchen , Wang Jiayu , Fan Xikang , Fu Zan , Ma Yanan , Hang Dong
Published: September 2021

Background

Insulin-like growth factor 1 (IGF1) is an important growth factor modulating development, homeostasis, and aging. However, whether and how circulating IGF1 concentrations influence early death risk in the general population remains largely unknown.

Methods

We included 380 997 participants who had serum IGF1 measurement and no history of cancer, cardiovascular disease (CVD), or diabetes at baseline from UK Biobank, a prospective cohort study initiated in 2006–2010. Restricted cubic splines and Cox proportional hazards regression models were used to assess the association between baseline IGF-1 concentrations and all-cause and cause-specific mortality.

Results

Over a median follow-up of 8.8 years, 10 753 of the participants died, including 6110 from cancer and 1949 from CVD. Dose–response analysis showed a U-shaped relationship between IGF1 levels and mortality. Compared to the fifth decile of IGF1, the lowest decile was associated with 39% (95% CI: 29–50%), 20% (95% CI: 8–34%), and 39% (95% CI: 14–68%) higher risk of all-cause, cancer, and CVD mortality, respectively, while the highest decile was associated with 17% (95% CI: 7–28%) and 38% (95% CI: 11–71%) higher risk of all-cause and CVD mortality, respectively. The results remained stable in detailed stratified and sensitivity analyses.

Conclusions

Our findings indicate that both low and high concentrations of serum IGF1 are associated with increased risk of mortality in the general population. Our study provides a basis for future interrogation of underlying mechanisms of IGF1 in early death occurrence and possible implications for mitigating the risk.
Die kartellrechtliche Bändigung von Preisalgorithmen
Authors: Zurth Patrick
Published: September 2021

Algorithmen ermöglichen mit ihren enormen Rechenkapazitäten neue Preisbestimmungsmethoden. Sie versetzen ihre Anwender in die Lage, auf Veränderungen bei Konkurrenzpreisen sofort zu reagieren oder Preise auf einzelne Konsumenten individuell zuzuschneiden. Der Beitrag zeigt ökonomische Nachteile eines umfassenden Einsatzes dieser Technologie auf und untersucht, wie das Kartellrecht auf die neuen Herausforderungen der algorithmischen Preise antworten kann. Für personalisierte Preise wird dabei eine Ausrichtung an aktuellen legislatorischen Entwicklungen und für potentielle Kollusionen eine Anpassung des bisherigen Verständnisses vorgeschlagen.
Spontaneous Massive Pneumomediastinum in a Previously Well Infant With COVID-19
Authors: Dixit Anushri , Uvaise Mohammed , Canet-Tarres Anna , Lillie Jon
Published: September 2021

A 3-month-old boy presented with a 3-hour history of a neck lump and difficulty breathing after 5 days of fever and reduced feeding. Pneumomediastinum with subcutaneous emphysema were identified, and the child was intubated because of severe work of breathing, requiring significant levels of oxygen and ventilatory pressure. Computed tomography chest scan revealed massive pneumomediastinum and significant bilateral parenchymal disease. The child deteriorated cardiovascularly, so the mediastinum was dissected by cardiothoracic surgeons and 2 drains were placed. The patient clinically improved with resolution of air leak over 2 days. A diagnosis of coronavirus disease 2019 pneumonia was confirmed.
The great zeroing of the sustainability of the global social order through the destruction of socio-cultural identification
Authors: Plaksina Oksana
Published: September 2021

The aim of the article is to deepen the knowledge about ensuring the sustainability of the society’s development as a system. The main methods of work ground on dialectical, systemic and activity-based interdisciplinary approaches and include analysis, synthesis, observation, the method of decomposition, typologization, complementarity, comparative analysis, logical and historical analysis. The novelty of the article lies in the study of the correlation between the destruction of socio-cultural identification and the unprecedented modern process – the zeroing of the sustainability of the general planetary society initiated by the top of the world capitalist class. Conclusions. New philosophical knowledge about the mechanisms of ensuring the stability of society has been received, taking into account the new challenges initiated by the deepening crisis of capitalism. New scientifically based results have been received: the specific of identification as a process and state have been discovered; there the subject of the world society’s sustainable development at this stage of history and in the future have been defined - humanity as a whole, and the object - the environmental functioning and harmonious development of humanity on a planetary scale. The analysis of the super-rich elite’s strategies and socio-political processes in the United States shows the following: 1. The destruction of socio-cultural identification is an effective frontal tool for the destabilization of social life, for the sustainability of individual societies and states, and society in general. 2. General social imbalance and the diminution of social sustainability, in turn, feed the breakdown of socio-cultural identification. 3. The destruction of socio-cultural identification is one of the demonstrations that the great zeroing of the world social order’s sustainability has begun. The main social contradiction of modernity has been revealed and a forecast of its development has been given.
The impact of socio-cultural integration strategies on the life activities of migrants
Authors: Rahimli Ruslan
Published: September 2021

The features of the integration of Azerbaijani immigrants into a single European socio-cultural space have been discussed in the article. Strategies for the integration of immigrants into the external socio-cultural environment have been described and the issues of socio-cultural acceptance of Azerbaijani immigrants in Europe have been studied from a scientific and theoretical point of view by examining their pros and cons.

The issues of adaptation, acculturation, separation, marginalization and transnationalism have been studied. It has been noted by the author that the active part of Azerbaijani immigrants in Europe is mainly people who have received higher education in the country of origin or in the country of their arrival, who plan to build a career in the society they come, who join socio- cultural processes, try to become a part of society that accepts local cultural values. At the same time, it has been noted in the article that young immigrants also participate in the acculturation process and the reasons for this have been investigated. The author has noted that immigrant Azerbaijanis prefer to contact or establish business with either Turks or Iranian Azerbaijanis or Eastern Europeans as it is more convenient for the middle and older generation to communicate with Turks in Turkish and with Eastern Europeans through Russian.

In the article observations of Azerbaijani immigrants in Berlin, Germany, from December 2017 to January 2018, as well as interviews with immigrants belonging to different social groups allow to say that first-generation immigrants almost do not have or are very weak in relations with local society, society institutions and their activity in the socio-cultural process is low.

The features and effects of transnationalism among Azerbaijanis living in Europe has also been examined in the article. It has been noted that transmigration is widespread among Azerbaijani immigrants living in Europe. The dual life of Azerbaijani immigrants as a transmigrant continues to grow. Although European Azerbaijanis already live in European countries, they have extensive ties with Azerbaijan and some even continue their working lives in both Europe and Azerbaijan. These immigrants are engaged in both business and other fields in the country of origin, acquire property in the country of origin, open offices and lead an active socio-cultural life in both the sending and receiving societies. It has been shown in the article that Azerbaijani immigrants are trying to connect the future of both themselves and their children with the country of origin, and those who have economic opportunities take more advantage of this opportunity.
ВПЛИВ СТУПЕНЮ ПОДРІБНЕННЯ AGARICUS BISPORUS І СОЄВОЇ ОЛІЇ НА РЕОЛОГІЧНІ ВЛАСТИВОСТІ, РОЗПОДІЛ ВОЛОГИ І МІКРОСТРУКТУРУ СІЧЕНИХ ВИРОБІВ ІЗ ПТИЦІ
Authors: Нан Хайцзюнь , Лi Бо , В. Кондратюк Наталія , А. Сильчук Тетяна , М. Степанова Тетяна
Published: September 2021

Ця стаття присвячена оцінці впливу розмірних характеристик порошку з печериці двоспорової (Agaricus bisporus) та соєвої олії як замінника жиру на реологічні властивості, розподіл вологи та мікроструктуру січених виробів із птиці. Було виготовлено чотири види різних зразків: контроль (20 % жиру), D1 (178 μm), D2 (100 μm) та D3 (34 μm) (60 % заміни жиру на порошок із печериці двоспорової різного ступеню подрібнення та соєву олію, відношення грибного порошку до соєвої олії становило 1 : 2). Було досліджено реологічні властивості (модуль пружності G' та пластичний модуль G''), мікроструктуру (SEM), T2 час релаксації (T2b, T21, T22) та поверхню релаксації (PT2b, PT21, PT22). Модуль пружності (G') та пластичний модуль (G″) січених виробів із птиці зростав зі зниженням розмірних характеристик частинок грибного порошку, що були вищими, ніж у контрольних зразків. Це вказує на те, що поєднання грибного порошку із різними розмірними характеристиками та соєвої олії може покращити в’язко-пружні властивості січених виробів із птиці. Зразки з розмірами частинок D2 (100 μm) та D3 (34 μm) мали подібний ефект за в’язко-пружними властивостями. T2b, T21, T22 та PT22 курячого фаршу з додаванням грибного порошку та соєвої олії були значно нижчими ніж у групи зразків (P < 0.05) зі зменшенням розміру частинок. Це свідчить про те, що додавання грибного порошку та соєвої олії прискорює перетворення вільної вологи у зв’язану в матриці присутніх гідроколоїдів. Зразки D1 мали найнижчий час релаксації T2b та найбільшу поверхню релаксації PT2b. При цьому зразки D1 мали найвищу вологоутримуючу здатність. Мікроструктура січених виробів із курки з внесенням грибних порошків з різним ступенем дисперсності та соєвої олії була більш рівномірною, порівняно з контрольними зразками. Зразки D2 та D3 мали схожу та рівномірну структуру, що вказує на те, що невеликі розмірні характеристики грибного порошку та соєвої олії можуть покращити текстурні властивості січених виробів із курки. Було визначено, що невеликі розмірні характеристики грибного порошку покращують в’язко-еластичні характеристики фаршів, в той час, як фарші з порошками з більшою дисперсністю, мають кращу вологоутримувальну здатність Описані у статті дані стануть корисними під час розробки нових та вдосконаленні існуючих технологій виробництва харчової продукції оздоровчого призначення.
A política brasileira sobre drogas e a rede de atenção psicossocial
Authors: Bulla Leonia Capaverde , Dos Santos Camila Bassôa
Published: September 2021

No Brasil, a temática das drogas tem sido abordada por diferentes tendências teóricas, em especial, pelo prisma da saúde pública em oposição ao proibicionismo. Tais tendências perpassam a construção da política nacional dessa área no contexto brasileiro, o qual tem sofrido com o desmonte das políticas sociais e a mercantilização da saúde. O presente artigo versa sobre uma pesquisa, na qual foram realizadas entrevistas com usuários de drogas, familiares, profissionais e gestores, nos diferentes níveis da rede de atenção psicossocial. Tal estudo permitiu discorrer sobre os avanços e entraves da efetivação das políticas na área além de evidenciar a importância da integralidade na oferta e acesso às políticas, bem como a intersetorialidade como pilar para atingir a atenção integral aos usuários de drogas. Reforça, também, a importância da luta popular por uma política fundamentada nos direitos humanos e que compreenda o uso de drogas em sua complexidade.
Irresolução, luto e elaboração em Orestes
Authors: Mesquita Cláudia Cardoso
Published: September 2021

Na trilha proposta pelo historiador alemão Andreas Huyssen (2014), que identifica uma preocupação central com a memória na cultura ocidental contemporânea, propomos, neste artigo, uma aproximação ao filme Orestes, atenta a seu esforço de rememoração crítica do período da ditadura militar no Brasil, entendido como força que age no presente (perpetuando um histórico de arbitrariedades e violências policiais). Sem desconsiderar suas singularidades — notadamente o uso da tragédia como máquina de compreensão histórica —, o filme de Rodrigo Siqueira nos permite examinar e especificar algumas hipóteses que desenhamos no contato com a produção fílmica contemporânea mais abrangente. Em especial a aposta em uma “estética da elaboração”: sob a sombra de um “passado que não passa”, o presente ganha centralidade nessa obra em que o próprio trabalho de elaboração da experiência, assumido em sua processualidade, encaminha a narrativa. Metodologicamente, buscamos “historicizar a estética”, como propõe Naara Fontinele dos Santos (2020): ao analisar as imagens, enredá-las na complexidade de processos históricos mais abrangentes de que os filmes participam.
Comparison between shear wave elastography and serological findings for the evaluation of fibrosis in chronic liver disease
Authors:   Radiology, The University of Lahore, Pakistan, Liaqat Mahjabeen , Siddique Kashif ,   Radiology, Shaukat Khanum Hospital, Pakistan, Yousaf Imran ,   Radiology, Shalamar Hospital, Pakistan, Bacha Raham ,   Radiology, The University of Lahore, Pakistan, Farooq S. Muhammad Yousaf ,   Radiology, The University of Lahore, Pakistan, Gilani Syed Amir ,   Radiology, The University of Lahore, Pakistan
Published: September 2021

Aim: In this study, we sought to examine the optimal cutoff values for predicting different stages of liver fibrosis, and to determine the level of agreement between shear wave elastography and aspartate aminotransferase to platelet ratio index (APRI) and fibrosis-4 index (FIB-4) scores in patients with chronic liver disease. Methodology: A descriptive, cross-sectional study was performed at the Radiology Department of Shaukat Khanum Memorial Hospital Lahore from 1 Jun 2019 until 1 June 2020. FIB-4 and APRI scores were determined by the following formula: FIB-4 = (age × AST) ÷ (platelet count × (√ (ALT)) and APRI = (AST÷AST upper limit of normal) ÷ platelet × 100. Data was analyzed with the help of SPSS version 24.0 and Microsoft Excel 2013. Results: Eighty individuals were conveniently selected, of which 62.5% were men and 37.5% were women. The mean age of the subjects was 43.47 SD ± 13.85 years. APRI and FIB-4 scores predicted F4 patients using the cutoff values of 0.47 (Sn. 72%, Sp. 70%) and 1.27 (Sn. 78%, Sp. 73%), respectively. The cutoff values of 0.46 for APRI and 1.27 for FIB-4 predicted F3–F4 patients (Sn. 74% and 77%; Sp. 76% and 76%), respectively. To predict F1–F4 compared to F0, the cutoff value was 0.34 (Sn. 68%, Sp. 75%) for APRI, while the cutoff value for FIB was 0.87 (Sn. 72%, Sp. 75%). The findings suggest that FIB-4 shows better diagnostic accuracy than APRI. Conclusion: This study provides optimal cutoff values for different groups of fibrosis patients for both serum markers. Also, the diagnostic accuracy of FIB-4 for predicting liver fibrosis was found to be superior to APRI in all disease stages.
Shear wave elastography in optic neuritis: diagnostic accuracy of the optic nerve and adjacent fat tissue values
Authors:   Radiology Department, Medıgold Sultan Hospıtal, Turkey, Aybar Mustafa Devran , Turna Onder ,   Radiology Department, Mehmet Akif Ersoy Training and Research Hospital, Turkey
Published: September 2021

Introduction: In this study, we attempt to determine the diagnostic performance of shear wave elastography of the optic nerve and adjacent fat tissue in patients with optic neuritis. Methods: The study included a patient group consisting of 72 eyes of 36 patients who were diagnosed with unilateral optic neuritis, and an age-matched control group of 36 eyes of 18 healthy subjects. The patient group consisted of 25 multiple sclerosis patients and 11 recurrent isolated optic neuritis patients. The mean shear wave elastography values of the optic nerves and intraorbital fat tissue adjacent optic nerves were recorded using m/s and kPa as units. ROC curve analysis was performed, and the diagnostic accuracy of shear wave elastography values was determined. Results: The mean shear wave elastography values of the optic nerves with neuritis (2.49 ± 0.41 m/s and 17.56 ± 4.42 kPa) were significantly higher than the values of the contralateral normal optic nerves (1.71 ± 0.32 m/s and 9.02 ± 2.34 kPa) (p = 0.006 and p = 0.004, respectively) in the optic neuritis group. The mean shear wave elastography values of intraorbital fat tissue adjacent optic nerves with neuritis (1.87 ± 0.32 m/s and 9.65 ± 1.12 kPa) were significantly higher than the values of the contralateral normal side (1.47 ± 0.27 m/s and 6.78 ± 1.14 kPa) (p = 0.025 and p = 0.022, respectively) in the optic neuritis group. ROC curve analysis showed a high diagnostic accuracy for determining optic neuritis with shear wave elastography values of the optic nerves (AUC 0.955 [95% CI, 0.933–0.978] in m/s and AUC 0.967 [95% CI, 0.940–0.985] in kPa). Conclusions: Shear wave elastography may be an important alternative diagnostic tool in the diagnosis of optic neuritis.
Rational conditions of fatty acids obtaining by soapstock treatment with sulfuric acid
Authors: Sytnik Natalia , Kunitsia Ekaterina , Mazaeva Viktoria , Kalyna Viktoriia , Chernukha Andrii , Vazhynskyi Serhii , Yashchenko Oleksandr , Maliarov Murat , Bogatov Oleg , Bolibrukh Borys
Published: September 2021

As a result of alkaline neutralization of oils, a significant amount of soapstock is formed, the utilization of which creates an environmental and economic problem. The production of fatty acids from soapstock using sulfuric acid decomposition is investigated in this work.
The peculiarity of the work is the determination of regression dependences of the yield and neutralization number of fatty acids on the soapstock processing conditions: temperature and duration.
Soapstock obtained after neutralization of sunflower oil was used as raw material. Soapstock indicators: mass fraction of moisture – 15.4 %, total fat – 71.9 %, fatty acids – 64.5 %, neutral fat – 7.4 %.
Rational conditions of soapstock processing are determined: temperature (90–95) °С, duration 40 min. Under these conditions, the fatty acid yield is 79.0 %, the neutralization number is 180.0 mg KOH/g. Quality indicators of the obtained fatty acids: mass fraction of moisture and volatile substances – 1.8 %, mass fraction of total fat – 97.0 %, cleavage depth – 64.5 % of oleic acid, the presence of mineral acids – no. Fatty acids correspond to fatty acids of the first grade according to DSTU 4860 (CAS 61788-66-7).
An increase in the temperature and duration of soapstock contact with sulfuric acid increases the yield and neutralization number of fatty acids. This is due to a decrease in the viscosity of the reaction medium, an increase in the depth of cleavage of soapstock soaps with sulfuric acid, an increase in the intensity and duration of mass transfer.
The developed rational conditions allow obtaining fatty acids from soapstock, which correspond in composition to fatty acids from refined deodorized sunflower oil.
The results allow solving a number of economic and environmental problems associated with soapstock utilization and can be implemented in oil refineries and fatty acid production
Justification of the use of square pipes in the frame of the removable roof of the open wagon
Authors: Fomin Oleksij , Lovska Alyona
Published: September 2021

This paper reports determining the basic strength indicators for the removable roof of a railroad gondola. It has been established that the typical roof design has a significant margin of safety in the components of the supporting structure. In order to reduce the roof material intensity, the reserves of its strength have been determined and optimized based on the criterion for minimal material intensity. Pipes of square cross-section have been proposed for using as the components of the roof frame.
When taking into consideration the proposed measures, it becomes possible to reduce the mass of the frame of the removable roof for a railroad gondola by almost 15 % compared to the typical design. At the same time, to apply the roof on different types of gondolas, its cantilevered parts can move in a longitudinal plane. It is possible to use deflectors on the removable roof. The roof can be attached to the body in a regular way. It is also possible to fix it using shog-connections.
To substantiate the proposed solution, the strength of the improved structure of the removable roof was determined. It was established that the maximum equivalent stresses in the load-bearing structure of the removable roof did not exceed permissible ones. To define the indicators of removable roof dynamics, its dynamic loading was investigated. The calculation was performed in a flat coordinate system. The oscillations in bouncing and galloping were taken into consideration as the most common types of a railroad car oscillations when running on a rail track. The mathematical model of dynamic loading was solved in the Mathcad software package (Boston, USA). The study has shown that the acceleration of the body in the center of masses is 0.4 g and is within the permissible limits. At the same time, the ride of a railroad car is excellent.
The study reported here would contribute to the improvement of the efficiency of railroad transportation.
Estimating the effect of aqueous cationic latex from the class of thermal elastic plastics on the properties of bitumen emulsions
Authors: Zhdaniuk Valeriy , Novakovska Victoria
Published: September 2021

To produce cationic bitumen emulsions, bitumen is used, whose penetration is not lower than 90 mm-1. Such bitumen has a small plasticity interval, which leads to a deterioration in its heat resistance at elevated temperatures and narrows the scope of application of emulsions based on it.
Based on the review of emulsion modification methods, the modification has been proposed that involves mixing the finished bitumen emulsions with aqueous cationic latex.
The process of interaction between a bituminous emulsion and an aqueous cationic latex has been considered. A mechanism for the disintegration of the modified bitumen emulsion on the surface of mineral materials was proposed. The emulsifiers have been selected and the composition of the aqueous phase has been chosen based on the analysis of surface tension isotherms. The influence of the modification on the properties of bitumen emulsions was investigated.
It was established that the main physicochemical characteristics of the interphase surface accept similar values for the aqueous phase and emulsions based on it.
It has been proven that the introduction of aqueous cationic latex quite moderately affects the basic physical-mechanical properties of emulsions, which makes it possible not to change the main technological parameters when using them.
It was established that increasing the concentration of the polymer in the emulsion has a positive effect on the physical-mechanical properties of the binder. With an increase in the concentration of the polymer to 6 % the softening temperature increases by 16 °C, elasticity is 74 %, and the holding capacity at minus 25 °C is approaching 100 %.
Improving the physical-mechanical properties of residual binder as a result of emulsion modification could increase the durability of layers in a roadbed based on bitumen emulsions and expand the scope of their application in the construction and repair of motorways
Development of low-pressure electric steam heater
Authors: Mekhtiyev Ali , Breido Iossif , Buzyakov Rustam , Neshina Yelena , Alkina Aliya
Published: September 2021

The study was devoted to solving the issue of creating new electric heating devices that can be used in autonomous heat supply systems. The issues were resolved by developing an original low-pressure electric steam heater. The study was aimed at improving the efficiency of heat supply systems for buildings and structures. Given the current trends in the global striving for energy conservation, it cannot be fully realized without the introduction of high-tech and low-energy-consuming electrical equipment. As a result of theoretical studies of a heat pipe with an electric heater, a design of an electrovacuum heating element has been developed. The low-pressure electric steam heater can be used in heat supply systems of autonomous users. Thermal energy transfer is currently accompanied by substantial energy losses since the heat carrier has to pass considerable distances. Switching of the facility to the heating plant is impossible in some cases because of technical problems or significant material costs for laying pipelines. As a result of the study, the dependence of heating the heat pipe at various volumes of the heat carrier and mass of the pipe itself was established. When a certain mass is reached, the temperature of the heating surfaces can reach 70 °C which is considered acceptable. The experimental data obtained have made it possible to develop an electric heater of new generation with a fundamentally new design of the heating element. It combines the efficiency of an electric spiral and comfortable warmth from a traditional radiator. This heater is an explosion and fire-safe and can be integrated into the Smart Home system
Constructing Steklov-type cubature formulas for a finite element in the shape of a bipyramid
Authors: Motailo Anzhelika , Tuluchenko Galina
Published: September 2021

This paper reports the construction of cubature formulas for a finite element in the form of a bipyramid, which have a second algebraic order of accuracy. The proposed formulas explicitly take into consideration the parameter of bipyramid deformation, which is important when using irregular grids. The cubature formulas were constructed by applying two schemes for the location of interpolation nodes along the polyhedron axes: symmetrical and asymmetrical. The intervals of change in the elongation (compression) parameter of a bipyramid semi-axis have been determined, within which interpolation nodes of the constructed formulas belong to the integration region, while the weight coefficients are positive, which warrants the stability of calculations based on these cubature formulas. If the deformation parameter of the bipyramid is equal to unity, then both cubature formulas hold for the octahedron and have a third algebraic order of accuracy.
The resulting formulas make it possible to find elements of the local stiffness matrix on a finite element in the form of a bipyramid. When calculating with a finite number of digits, a rounding error occurs, which has the same order for each of the two cubature formulas.
The intervals of change in the elongation (compression) parameter of the bipyramid semi-axis have been determined, which meet the requirements, which are employed in the ANSYS software package, for deviations in the volume of the bipyramid from the volume of the octahedron.
Among the constructed cubature formulas for a bipyramid, the optimal formula in terms of the accuracy of calculations has been chosen, derived from applying a symmetrical scheme of the arrangement of nodes relative to the center of the bipyramid. This formula is invariant in relation to any affinity transformations of the local bipyramid coordinate system. The constructed cubature formulas could be included in libraries of methods for approximate integration used by those software suites that implement the finite element method.
Influence of yttrium and niobium oxides modifiers on physicochemical and photocatalytic properties of titanium (IV) oxide
Authors: Kyrii Svitlana , Dontsova Tetiana , Kosogina Iryna , Podopryhor Valeriia , Serhiienko Alla
Published: September 2021

The photocatalytic and physicochemical properties of titanium (IV) oxide modified by yttrium and niobium oxides were studied. It is shown that modification is a powerful way to increase the efficiency of catalysts' photocatalytic properties and improve the photocatalytic process as a whole. Commercial and laboratory-synthesized titanium (IV) oxides were used as catalysts for modification. Modification of titanium (IV) oxide powders in an amount of 1 wt. % by appropriate modifiers was performed by the hydrothermal method, after which they were characterized by diffraction and X-ray fluorescence methods. The structural characteristics of modified and non-modified titanium (IV) oxide samples by the method of low-temperature nitrogen adsorption-desorption have been studied. A slight increase in the specific surface area was found: from 61 m2/g to 70 m2/g for the commercial sample and from 172 m2/g to 180 m2/g for the synthesized one in this work. Similar dependencies are observed when studying the optical properties by the spectrophotometric method. Determination of surface properties (surface acidity) of modified and non-modified photocatalysts based on TiO2 showed different effects of modifiers on TiO2 acidity: in the modification by yttrium oxide, the acidity decreases, and in the case of niobium oxide – increases. Studies of photocatalytic and sorption activities with respect to dyes of different nature are not the same – the photocatalytic activity after modification increases, the sorption capacity with the cationic dye decreases, anionic – increases. Additional studies on dye destruction are in full accordance with photocatalytic and sorption experiments.
Devising scientific and methodological tools to strengthen the economic security of a region through the improvement of technologies for marketing support of tourism
Authors: Ratynskyi Vadym , Tymoshyk Nataliia , Sherstiuk Roman , Dudkina Olena , Dunayev Igor , Petrovska Iryna , Mital Olena , Nosyriev Oleksandr
Published: September 2021

The concept of marketing support for strengthening the economic security of a region by intensifying tourist business was developed. It was established that the economic security of a region is the result of the influence of a number of processes of different nature and degrees of influence. The safety assessment depends on its purpose and groups of partial indicators that provide a comprehensive assessment. The result of the evaluation procedure should be a grounded conclusion on one of the possible states: economic security, economic danger, economic risk, and economic threat. The tourism sector, influencing the level of security of a region through the generation of additional financial and related flows, requires clarification of the content of scientific and methodological approaches to management. It is proposed to separate administrative methods and market mechanisms as complementing each other. At the level of separate tourist enterprises and their associations, it is advisable to implement marketing strategies for traditional expansion of the market, product, and innovative updating of the portfolio of tourist products. The main tools and technologies for achieving set goals are digital information and communication technologies. Their application is associated with the use of the method for economic and mathematical modeling, as well as SWOT analysis technology and the use of a special BITOUR platform. The use of the proposed theoretical and methodical proposals will make it possible to assess the economic security of a region in terms of its possible condition. It will also be useful in the development of strategic and tactical plans for regulating tourism business in the system of ensuring the economic development of a region.
Analysis of performance parameters for wireless network using switching multiple access control method
Authors: Shijer Sameera Sadey , Sabry Ahmad H.
Published: September 2021

The developments of wireless networks have directed to search for opportunities of a broad diversity of improved and new networking contributions. Wireless Asynchronous Transfer Mode (ATM) is a non-synchronous or random mode of transferring information. The advantages of circuit switching include dedicated connections and guaranteed traffic parameters and the benefits of packet switching are the efficiency at the physical layer and a more cost-effective design. ATM is the only protocol that offers the best of both communication methods. Although the Variable Bit-Rate (VBR) transmission presents a promising prospective of stable data quality, it is usually accompanied by network traffic overload and cell packet loss, which extensively weakens that potential. This work overcomes these concerns by developing a switching-based multiple access control model to improve the data transmission performance of wireless ATM. Therefore, this work discusses the effectiveness of the developed approach to minimize the cell packet losses and network traffic overload in wireless ATM. Three control access is processed; polling, token passing, and reservation algorithms for collision avoidance. The reservation stage reserves the data before sending, which includes two timeline intervals; a fixed-time reservation period, and variable data transmission interval. Using OPNET 10.5, the results show that the presented switching-based multiple access control model can achieve a throughput value of 98.3 %, data transmission delay of about 40.2 ms, and 0.024 % of packet losses during data transmission between the source and destination. It is demonstrated that the introduced method effectively transmits information without creating any network complexity and delay
Improving the ecological safety of potato chips production by devising a method for wastewater treatment and recycling
Authors: Hetta Oksana , Shestopalov Oleksіi , Duhanets Viktor , Shubravska Olena , Rudkovskyi Oleksandr , Paraniak Nаdiia , Riazanova-Khytrovska Nataliia , Maksimenko Olena
Published: September 2021

The study deals with determining the effectiveness of mechanical and physical and chemical methods for the treatment of wastewater of potato chips enterprises. It was established that the wastewater that is formed at different stages of production differ in composition. Wastewater after washing and peeling potatoes is contaminated mainly with suspended soil substances of about 500 mg/l, which are not settled, and also has soluble organic substances with a value of COD of about 1,000 mg/l.
It was found that the use of coagulation-flocculation treatment makes it possible to get clear water suitable for reuse for washing potatoes. Coagulant – aluminum sulfate in the amount of 250 mg/l turned out to be effective to destroy the stability of the dispersed system. To intensify the sedimentation of coagulated flakes of suspended particles, non-ionogenic flocculant, which is recommended to be dosed after the introduction of coagulant in the amount of 2.5 ml/l, was selected. Analysis of clarified water indicates a decrease in the concentration of suspended particles up to 26 mg/l and a decrease in COD and BOD5 to values of 262 mg/l and 176 mg/l, respectively.
The completed studies made it possible to propose a circuit of treatment of wastewater after washing potatoes, which consists of pre-filtering, reagent treatment, water clarification, and sediment dehydration. This circuit makes it possible to intensively clean the water to the standards of its discharge into the sewage network. However, additional disinfection of water with oxidizers, for example, ozone, was proposed for the reuse of clarified water to wash vegetables at an enterprise itself.
The use of the proposed circuit of intensive water treatment will allow increasing the environmental safety of the production of potato chips by preventing environmental contamination through reducing the volume of tap water consumption
Determination of influence of pH on reaction mixture of ferritation process with electromagnetic pulse activation on the processing of galvanic sludge
Authors: Kochetov Gennadii , Samchenko Dmitry , Arhatenko Tetiana
Published: September 2021

This paper considers prospects for increasing the level of environmental safety of industrial enterprises as a result of the implementation of resource-saving technology of processing galvanic sludge using the ferritization method. The effectiveness of the use of electromagnetic pulse discharges for resource-saving activation of the ferritization process with the extraction of heavy metal ions from sludge (Fe, Ni, Cu, Zn) has been confirmed. The influence of key parameters of the process such as the pH value of the reaction mixture and the initial concentrations of metals in the solution on the quality of processing galvanic sludge by ferritization has been experimentally investigated. It was determined that with an increase in the pH value from 8.5 to 10.5 the residual concentrations of metal ions decrease to the values of 0.1÷0.25 mg/dm3 regardless of the total initial concentrations. It has been established that the technique of electromagnetic pulse activation ensures an adequate degree of extraction of metal ions of 99.9 %; it also has indisputable energy advantages compared to the thermal method: energy costs are reduced by more than 60 %. That indicates the suitability of purified water for reuse in galvanic production in terms of the requirements for the content of heavy metal ions in it. In addition, the structural studies of ferritization sediment samples have been carried out. The sediment is characterized by the maximum content of crystalline ferromagnetic phases of ferrite. It was established that an increase in the pH of the initial reaction mixture leads to an increase in the ferrite phase in sedimentation: at pH=10.5, phases were detected, which are characterized by a maximum ferrite content (exceeding 76 %). The proposed resource-saving ferritization process prevents environmental pollution, ensures efficient and rational utilization of raw materials and energy in the industry; it also makes it possible to obtain commodity products from industrial waste.
Development of the model and the method for determining the influence of the temperature of gunpowder gases in the gun barrel for explaining visualize of free carbon at shot
Authors: Brunetkin Olexander , Maksymov Maksym , Brunetkin Vladimir , Maksymov Оleksii , Dobrynin Yevhenii , Kuzmenko Vitalii , Gultsov Pavlo
Published: September 2021

A phenomenon that is present in almost every shot is highlighted. It manifests itself in the muzzle discharge as a certain amount of free carbon. The thermochemical reaction of Boudouard-Bell (disproportionation of carbon monoxide) was determined, which explains the formation of free carbon in the gunpowder gases during the firing process. A feature of this reaction is the formation of a condensed phase of carbon during the firing process after the gasification of the gunpowder charge.
The reason is revealed that does not allow describing the formation of free carbon during firing on the basis of existing models of internal ballistics processes. It is the lack of taking into account the temperature distribution of the gunpowder gases along the length of the gun barrel and its change. A mathematical model is proposed that makes it possible to estimate the temperature distribution during the shot.
A method has been developed for solving the problem of internal ballistics with the ability to determine the temperature of gunpowder gases along the length of the gun barrel at different times and at different positions of the projectile in the barrel. The original model is built using generally accepted assumptions. Modeling results can only be estimated. For this reason, the method is based on simple calculations, which makes it possible not to involve high-power computing equipment.
The modeling of the temperature distribution of gunpowder gases in the space of the gun barrel between the charging ball and the moving projectile in the model system is carried out. The possibility of changing the length of the zone of the Boudouard-Bell reaction (the zone of formation of free carbon) depending on the initial data is shown. The use of a fresh gunpowder charge and a degraded one is simulated. Full and reduced charges are considered. The simulation results showed the reason for the possibility of initiating a secondary muzzle discharge flash both from the front side and from the side of the muzzle brake.
Improvement of trawler hull structure under condition of ensuring fatigue strength
Authors: Korostylov Leontii , Lytvynenko Dmytro , Sharun Hryhorii , Davydov Ihor
Published: September 2021

The structure of the hull of the project 1288 trawler in a region of fore hold was improved to ensure fatigue strength of assemblies of the intersection of main frames with the second bottom. To this end, a study of the fatigue strength of these assemblies was carried out for the original side structure and two versions of its modernization.
Values of internal forces at the points of appearance of fatigue cracks in the compartment have been determined for three design versions of the side. It was found that the greatest forces act in the middle of the fore half of the compartment.
Calculations of parameters of the long-term distribution of magnitudes of ranges of total equivalent operating stresses according to the Weibull law in the points of occurrence of fatigue cracks for different design versions of the side grillage have been performed. These parameters were determined for the middle of the fore hold of the vessel and for the areas in which maximum values of bending moment ranges are in effect with and without corrosive wear.
Values of total fatigue damage and durability of the studied assemblies were determined. Calculations were carried out by nominal stress method, hot spot stress method, and experimental and theoretical method.
It was shown that in order to ensure fatigue strength of the assembly under consideration, it is necessary to extend the intermediate frames of the original version of the side structure to the level of the second bottom fixing them to the deck. It is also necessary to attach a cargo platform to the side thus reducing the frame span. As a result, the level of fatigue damage over 25 years of operation will decrease by about 3.5 times.
As it was found, approximate consideration of the slamming effect does not significantly increase the amount of fatigue damage to the assembly.
The results of the development of recommendations for modernization of the side structure can be implemented both on ships of the 1288 project and on other ships with a transverse side framing system.
Development of security systems using DNN and i & x-vector classifiers
Authors: Mamyrbayev Orken , Kydyrbekova Aizat , Alimhan Keylan , Oralbekova Dina , Zhumazhanov Bagashar , Nuranbayeva Bulbul
Published: September 2021

The widespread use of biometric systems entails increased interest from cybercriminals aimed at developing attacks to crack them. Thus, the development of biometric identification systems must be carried out taking into account protection against these attacks. The development of new methods and algorithms for identification based on the presentation of randomly generated key features from the biometric base of user standards will help to minimize the disadvantages of the above methods of biometric identification of users. We present an implementation of a security system based on voice identification as an access control key and a verification algorithm developed using MATLAB function blocks that can authenticate a person's identity by his or her voice. Our research has shown an accuracy of 90 % for this user identification system for individual voice characteristics. It has been experimentally proven that traditional MFCCs using DNN and i and x-vector classifiers can achieve good results. The paper considers and analyzes the most well-known approaches from the literature to the problem of user identification by voice: dynamic programming methods, vector quantization, mixtures of Gaussian processes, hidden Markov model. The developed software package for biometric identification of users by voice and the method of forming the user's voice standards implemented in the complex allows reducing the number of errors in identifying users of information systems by voice by an average of 1.5 times. Our proposed system better defines voice recognition in terms of accuracy, security and complexity. The application of the results obtained will improve the security of the identification process in information systems from various attacks.