bluuebunny/crossref_metadata_2025 huggingface dataset:
Elaboration of a criterion heat transfer equation of electrostatic fields influence in kerosene medium at free convection and deposit formation
Authors: Altunin K.V.
Published: February 2021

The paper focuses on the problem of deposit formation in engines and power plants operating on liquid hydrocarbon fuels and coolers, and analyzes hydrocarbon deposit formation on heated fuel-delivery metal at increased temperature. First, an experimental setup was created to study the effect of electrostatic fields on the heat transfer intensification in liquid aviation kerosene TS-1 and the process of deposit formation on a heated working plate. Then, the effect of electric wind on thermal processes was visualized using the Tepler optical setup and the influence of electrostatic fields on the processes of heat transfer of deposit formation in the kerosene medium when using coaxial needles as electrodes was studied. Finally, findings of the research were generalized and a new criterion equation with a created dimensionless similarity number of electric convection and deposit formation simplex was introduced.
Development of 25N oxygen-kerosene thruster
Authors: Salich V.L.
Published: February 2021

The paper introduces the scientific and technical groundwork obtained by the author and used as a basis for the development of an oxygen-kerosene rocket engine with a thrust of 25 N. This groundwork represents the results of research carried out on an experimental chamber developed by the author. The design of the chamber made it possible to study the effect of the configuration of the mixing element on its characteristics, the number of holes of oxygen supply to the internal cooling curtain, the length of the cylindrical section behind the curtain belt. The results of tests of various variants of the chamber and their analysis are presented. The results of tests of the developed engine, in which one of the camera variants is implemented, are given as well.
Numerical simulation of flow patterns of modified bullets at subsonic flight speeds
Authors: Moskalenko V.O. , Ilukhin S.N. , Bulavina V.V.
Published: February 2021

The purpose of the study was to carry out a numerical simulation in a special package of the subsonic air flow around a pneumatic bullet of various modifications, the latter being previously experimentally tested on the ballistic track of the Department of Dynamics and Flight Control of Rockets and Spacecraft at Bauman Moscow State Technical University. The paper briefly analyzes the applicability of the most common computing packages for solving the problem, justifies the use of the ANSYS CFX package, describes the requirements and features of the computational grid construction, and gives the boundary conditions. The verification problem was solved, which showed good correspondence of the constructed model to the results of field shooting carried out in previous studies. The influence of the longitudinal rotation of the reference model of the bullet on the pattern of its flow and aerodynamic characteristics were investigated. The results of the calculations confirmed the drag improvement and bullet dispersion effects obtained when testing a number of modified samples. The calculated flow patterns and pressure fields contributed to a complete understanding of the physics of the studied modifications in a wide range of flight speeds.
Life Strategies of the Parents of Children with Intellectual Disabilities in the Context of Mixed Social Situations
Authors: Niedbalski Jakub
Published: February 2021

This paper aims to analyze the phenomenon of the managing of the stigma of a child’s disability by their parents. Using the concept of stigma by Erving Goffman, I point to its usefulness in understanding the management of stigma by parents of children with intellectual disabilities in the context of mixed social situations. The research utilizes qualitative techniques with special emphasis on unstructured interviews. The data analysis was performed following the procedures of the grounded theory. As studies have shown, parents of children with disabilities adopt various strategies and tactics during the encounters with other persons and institutions while dealing with everyday hardships.
Post-Foucauldian Discourse and Dispositif Analysis in the Post-Socialist Field of Research: Methodological Remarks
Authors: Nowicka-Franczak Magdalena
Published: February 2021

Post-Foucauldian discourse and dispositif analysis, a methodological approach inspired by the work of Michel Foucault and developed in Western Europe, over the last decade has gained an increasing amount of attention from Eastern European researchers. Yet, this interest has not been accompanied by sufficient reflection on the post-Foucauldian perspective’s adequacy for studying power, governance, and subjectification in post-socialist societies. In particular, there is little criticism that would take into account the current discussion on Foucault’s ambivalent attitude towards neoliberalism. The goal of this article is to examine this line of criticism of Foucault’s late works and to point to its importance for dispositif analysis carried out in Eastern and Central European societies (e.g., Poland) in comparison to analyses carried out in Western Europe (e.g., Germany). I propose a number of methodological recommendations that aim at adapting post-Foucauldian research instruments to facilitate analyzing power relations in the post-socialist context; these include: an interdisciplinary combination of discourse analysis and an analysis of macroeconomic and macrosocial factors; an analysis of the practices of normalization in post-socialist societies with reference to the Center-Periphery relationship; introducing elements of semiology, anthropology of the contemporary and cultural identity analysis to dispositif analysis.
Effects of Beta-carotene Administration on Fertility in Lactating Dairy Cows
Authors: Bilen Ebru Karakaya , Mecitoglu Gülnaz Yılmazbaş
Published: February 2021

Background: Beta-(β-) carotene, is the precursor to vitamin A, in particular, has some potential benefits on reproduction. The main objective of this study was to investigate the efficacy of β-carotene administration on fertility following either prostaglandin F2 alpha (PGF) induced estrus or Ovsynch protocol in lactating dairy cows. Methods: Cows with at 47±3 postpartum days were divided into two groups: β-carotene group (βC, n=139) was treated with injectable β-carotene while untreated cows served as control (CON, n=227). In both groups, PGF was administered and heatmount detectors were applied at 54±3 days postpartum. Cows detected in estrus after PGF were inseminated. Cows that had not been detected in estrus were divided into two groups 7 days after PGF administration; βC-OVS (n=137) and CON-OVS (n=89). Ovsynch protocol was initiated 4 days after β-carotene administration. Result: The estrus detection rate was similar between the βC and CON groups (P = 0.19). Pregnancy per AI (P/AI) on d 31 was also similar between groups (P = 0.93). In the Ovsynch protocol, ovulation to the first GnRH and ovulatory follicle diameter at the time of insemination did not differ between groups. No difference was observed in P/AI at d 31 (P = 0.13). The results of this study indicated that β-carotene administration had no effect on fertility either PGF induced estrus or Ovsynch protocol in dairy cows.
Desarrollo histórico-epistemológico del álgebra: evolución hacia distintos significados
Authors: Mejías Cristian , Alsina Ángel
Published: February 2021

En este artículo se realiza una revisión del desarrollo histórico-epistemológico del álgebra. Indagamos acerca de su surgimiento desde la prehistoria hasta tiempos actuales; examinamos los aportes de la cultura egipcia, babilónica y china, entre otras, junto con un análisis del impacto que realizaron los árabes y los griegos en esta materia; y se muestra el tránsito hacia la consolidación del álgebra elemental, lineal, multilineal, homológica, conmutativa, no conmutativa y Booleana. Considerando estos antecedentes, presentamos una primera aproximación hacia una teoría del álgebra que considera distintas representaciones de ella, como es el significado intuitivo, clásico y matemático-axiomático.
Etude Comparative De La Croissance Et De La ProductivitÃ© Chez Le Taro (Colocassia Esculenta L.) Et Le Macabo (Xanthosoma Sagittifolium, Et X Anthosoma Sp) CultivÃ©s Dans Les Conditions PÃ©doclimatiques De La Ville De MbaÃ¯ki (Lobaye) En RÃ©publique Centrafric
Authors: Touckia Gorgon Igor , Yongo Olga Diane , Kosh Komba Ephrem , Alato Raba , Kokou Kouami
Published: February 2021

Methods: In order to evaluate the growth and production of taro, Colocassia esculenta, macabo, Xanthosoma sp and Xanthosoma sagittifolium varieties, a randomized Fischer block experimental design was set up. The trials were set up in the localities of MbaÃ¯ki in the southern part of the Central African Republic. The effects of varieties on growth and production parameters were assessed using analysis of variance (ANOVA) at a classification criterion with Software R version 3.1.3. Results: The vegetative growth and production parameters evaluated showed variability between the different varieties grown. Good vegetative growth was observed in macabo varieties, while in Taro, production was better, with the number of tubers per plant (16.83) and a yield of 13,260 t/ha against 11.42 t/ha and 5.30 t/ha for macabo varieties (V2 and V3). Conclusion: The varieties grown showed high yields except for the macabo variety V3 which had a lower yield than the average for the sub-region.
MÃ©thodes.- Dans lâ€™objectif dâ€™Ã©valuer la croissance et la production des variÃ©tÃ©s de taro, Colocassia esculenta, de macabo, Xanthosoma sp. et European Scientific Journal, ESJ ISSN: 1857-7881 (Print) e - ISSN 1857-7431 January 2021 edition Vol.17, No.3 www.eujournal.org 108 Xanthosoma sagittifolium, un dispositif expÃ©rimental en blocs de Fischer randomisÃ© a Ã©tÃ© mise en place. Les essais ont Ã©tÃ© installÃ©s dans les localitÃ©s de MbaÃ¯ki dans la partie sud de la RÃ©publique Centrafricaine. Les effets de variÃ©tÃ©s sur les paramÃ¨tres de croissance et de production ont Ã©tÃ© apprÃ©ciÃ©s grÃ¢ce Ã  lâ€™analyse de variance (ANOVA) Ã  un critÃ¨re de classification avec le Logiciel R version 3.1.3. RÃ©sultats.-Les paramÃ¨tres de croissance vÃ©gÃ©tative et de production Ã©valuÃ©s ont mis en Ã©vidence une variabilitÃ© entre les diffÃ©rentes variÃ©tÃ©s mises en culture. Une bonne croissance vÃ©gÃ©tative a Ã©tÃ© observÃ©e chez les variÃ©tÃ©s de macabo, tandisque chez le taro, la production a Ã©tÃ© meilleure, avec le nombre de tubercules par pied (16,83) et un rendement de 13,260 t/ha contre 11.42 t/ha et 5,30t/ha pour les variÃ©tÃ©s de macabo (V2 et V3). Conclusion.-Les variÃ©tÃ©s mises en culture ont prÃ©sentÃ© des rendements Ã©levÃ©s exceptÃ© la variÃ©tÃ© de macabo V3 qui a rendement infÃ©rieur par rapport Ã  la moyenne de la sous-rÃ©gion.
Covid-19 Pandemic Situation In The Arab World Till June 11, 2020: Spatial Panorama Obtained Following The Response Plan Implemented
Authors: Hadrya Fatine , El Hattimy FaiÃ§al , Hami Hind , Mokhtari Abdelrhani , Soulaymani Abdelmajid
Published: February 2021

Background: The COVID-19 pandemic is a global health emergency of this century. The Arab region is not spared from this scourge. This paper focuses on describing the current epidemiological situation of Coronavirus Disease 2019 (COVID-19) in the Arab world, as of June 11, 2020. Methods: An observational study of all laboratory-confirmed cases of COVID-19, reported in each Arab country since the appearance of the first case until June 11, 2020, was carried out. Results: Twenty-two Arab countries have reported a total of 398,954 confirmed cases of COVID-19 and 5,241 deaths, with a cumulative incidence of 950 cases per 1,000,000 population and a cumulative mortality rate of 13 deaths per 1,000,000 population. Of all recorded cases, 240,137 (60.19%) have recovered from COVID-19. The highest incidence rate of COVID-19 was observed in Qatar (26,988 cases per 1,000,000 population) and the lowest incidence was recorded in Libya (59 cases), Yemen (21 cases), and Syria (10 cases). Kuwait had the highest mortality rate for COVID-19 (67 deaths per 1,000,000 population). Eight countries had a case fatality rate (CFR) less than 1% (e.g., Bahrain, Oman and Qatar). The highest CFR was observed in Yemen (23.01%). Only three countries were ranked first in terms of remission (Morocco, Palestine and Tunisia). The rate of remission did not exceed 20% in Libya, Mauritania, and Yemen. Conclusion: Some countries were more affected than others in terms of morbidity and mortality. The success of a national response plan against COVID-19 is closely linked to the devotion of health professionals and community engagement.
Detection Of Fecal Coliforms In Water Used In Formal And Informal Food Outlets In Kasungu District, Malawi
Authors: Chavura Elton , Kapute F. , Chingatichifwe Mbakaya Balwani
Published: February 2021

Poor sanitary practices are common amongst many food handlers posing a health risk to consumers. Maintenance of high quality water is one of the most important aspects of ensuring consumer safety. Therefore, regular water testing is critical in public food outlets where bacterial contamination may cause outbreak of disease. The study aimed at analyzing water samples obtained from the formal and informal food outlets for the presence of fecal coliforms that are indicative of poor sanitation that result in foodborne infections amongst consumers. Using a cross-sectional design, water samples from participating food outlets (N=40) were analyzed using the membrane filtration method. Samples were filtered, under vacuum, through a cellulose acetate membrane of 0.45 Î¼m pore size. Fecal coliforms exceeding permissible range were detected in 15 test samples (N=40). The median (IQR) concentrations of fecal coliforms (FC/100ml) in dishwashing water was 1(136) and 145(340) for the formal and informal food outlets respectively. The median (IQR) for drinking water was 0(0) with a minimum and maximum range of 0 and 14 FC/100mls. The study established a positive correlation between fecal coliforms and electrical conductivity, and total dissolved solids (p<0.05) in dish washing water used at both formal and informal food outlets. Contamination was attributed to lack of running water, poor pest control and unwholesome practices in many food outlets. Based on the study findings, it is concluded that electrical conductivity, total dissolved solids and turbidity values may be used to deduce the presence of fecal coliforms in water. The study recommends that water drawn from unprotected sources must be boiled or treated at the point of use before it can be safely used in food outlets. Periodic water testing and sanitary supervisions for all food outlets must be mandatory to ensure compliance with minimum set standards.
AccÃ¨s Ã€ La Terre Et Profil De La PauvretÃ© Dans Le Delta Du Fleuve SÃ©nÃ©gal
Authors: Sylla El Hadji Malick , Sy Karalan , Mohamed Seck Sidy
Published: February 2021

Cet article tente de caractÃ©riser les mÃ©nages agricoles pauvres dans le Delta du fleuve SÃ©nÃ©gal aprÃ¨s la crise alimentaire de 2008, durant laquelle les politiques publiques ont rÃ©alisÃ© des amÃ©nagements hydroagricoles pour lutter contre la pauvretÃ© et lâ€™insÃ©curitÃ© alimentaire. Il sâ€™appuie sur des enquÃªtes de terrain auprÃ¨s des producteurs. Les rÃ©sultats montrent une forte inÃ©galitÃ© entre les cultivateurs en termes de capital foncier et de surfaces cultivÃ©es. Aussi les mÃ©nages les plus pauvres sont-ils ceux qui nâ€™emblavent pas assez de superficies, qui ne cultivent quâ€™en contre-saison chaude et, par consÃ©quent, ne gagnent pas assez de revenus agricoles pour amÃ©liorer leur condition de vie.
This paper attempts to characterise poor farming households in the Senegal River Delta after the 2008 food crisis, during which public policies implemented hydro-agricultural developments to combat poverty and food insecurity. It is based on field surveys of producers. The results show a strong inequality between farmers in terms of land capital and cultivated areas. As a result, the poorest households are those that do not cultivate enough land, only cultivate in the off-season and therefore do not earn enough agricultural income to improve their living conditions.
The Effect of Non-partisan Elections and Decentralisation on Local Government Performance
Authors: Richards Robin
Published: February 2021

This rapid review focusses on whether there is international evidence on the role of non-partisan elections as a form of decentralised local government that improves performance of local government. The review provides examples of this from Sub-Saharan Africa and South Asia. There are two reported examples in Sub-Saharan Africa of non-partisan elections that delink candidates from political parties during election campaigns. The use of non-partisan elections to improve performance and democratic accountability at the level of government is not common, for example, in southern Africa all local elections at the sub-national sphere follow the partisan model. Whilst there were no examples found where countries shifted from partisan to non-partisan elections at the local government level, the literature notes that decentralisation policies have the effect of democratising and transferring power and therefore few central governments implement it fully. In Africa decentralisation is favoured because it is often used as a cover for central control. Many post-colonial leaders in Africa continue to favour centralised government under the guise of decentralisation. These preferences emanated from their experiences under colonisation where power was maintained by colonial administrations through institutions such as traditional leadership. A review of the literature on non-partisan elections at the local government level came across three examples where this occurred. These countries were: Ghana, Uganda and Bangladesh. Although South Africa holds partisan elections at the sub-national sphere, the election of ward committee members and ward councillors, is on a non-partisan basis and therefore, the ward committee system in South Africa is included as an example of a non-partisan election process in the review.
Estimation of the red deer population and its impact on the Tugay forest ecosystem in the Lower Amu Darya State Biosphere Reserve, Uzbekistan
Authors: CORNELIS Daniel , KAN Elena , GOND Valéry , CESARO Jean-Daniel , PELTIER Régis
Published: February 2021

In 2011, the Government of Uzbekistan established the Lower Amu Darya State Biosphere Reserve (LABR). This reserve aims to conserve the Tugay, an endangered riparian forest ecosystem straddling the main rivers of Central Asia’s drylands, which is under extreme anthropogenic pressure. The LABR has reintroduced Bukhara red deer (Cervus hanglu bactrianus), a subspecies endemic to Asia whose numbers declined severely over the 20th century. The LABR development project aims to provide operational support to the Uzbek authorities for their application to join the World Network of Biosphere Reserves. GIZ (German Society for International Cooperation) requested CIRAD to provide a science-based estimate of the deer population in the LABR, using an internationally recognized method, and to issue recommendations to ensure ecologically and socio-economically sustainable management. The survey of the Bukhara red deer population began in October 2019. The study area covered 88 km2. The survey design consisted of 12 parallel straight lines 1400 m apart; the total transect length was 65 km. During the count, 127 observations of individuals or herds were made and a total of 336 individuals were observed. The data were analysed using DISTANCE 7.3 software. The encounter rates were 1.95 obs./km and 5.17 animals/km. The estimated density was 24 deer/km2 and the estimated total population was 2,112 deer [1,320 - 3,344, 95% CI]. The proportion of dead, dying or severely affected trees was roughly estimated at 10%, and the proportion of trees affected but with a good chance of survival at 15%. In the southern core area of the LABR, a very high proportion of seedlings and suckers was being eaten and the forest is no longer regenerating. Maintaining a population of 24 deer/km2 in the southern core area of LABR clearly seems incompatible with either the conservation of the Tugay forest ecosystem or the peaceful coexistence of deer with human populations adjacent to the LABR. Options to mitigate deer pressure include translocation to the northern core area of the LABR or other areas, and regulation of the deer population. The density is too high to ensure effective preservation of the species locally, although the deer population is under severe pressure in Asia as a whole.
Rural communes and Soviet farms on the eve and during the peasant rebellion of 1920–1921
Authors: Bezgin Vladimir B.
Published: February 2021

We examine the state of communes and farms, the attitude of the rural population to their organization and activities, as well as the state of collective farms on the eve and during the Tambov rebellion of 1920–1921. The relevance of the topic is determined by the need for a scien-tific understanding of the problem of insurrection in the Civil War and its manifestation in the form of a peasant rebellion led by A.S. Antonov. The purpose of the study is to establish the fate of collective farms during the armed protest of the Tambov peasants. The work was carried out on the basis of a wide range of archival sources, some of which are introduced into scientific circulation for the first time. The analysis of the problem is carried out taking into account the achievements of modern historiography of the issue and the use of scientific tools of advanced methodological approaches. We apply the entire arsenal of methods of historical research based on the principles of historicism, objectivity and consistency. It is established that the armed raids of rebel detachments on agricultural communes, Soviet farms were due to the need of the partisans for food, horses, forage, and the active participation of the local population in them stemmed from their view of the land and property of collective farms as rightfully belonging to them.
Legal discourse as a subject of study and teaching in the classroom in a foreign language specialty
Authors: Novikova Ekaterina R. , Polyakov Oleg G. , Hausmann-Ushkova Nadezhda V.
Published: February 2021

The current state of the problem of studying and teaching foreign language legal discourse is presented. Various points of view on discourse as an interdisciplinary phenomenon are analyzed. Legal discourse is considered as a kind of institutional discourse. Communication of participants in legal discourse is carried out on the basis of a certain number of rules that govern their role and normative behavior. In their actions, there is coordination inherent in this form of communication and allowing the participants in legal discourse to be perceived as components of a single whole – a larger institutional system. A brief description of the functions of legal discourse is given – prescriptive, informative, argumental, declarative, regulatory, interpretive, cumulative, presentation, strategic and code. Such properties of legal discourse as performativity and intertex-tuality are discussed, and its components are described. The difference between legal texts, in which the discourse of law is implemented, from texts of other specialties is shown. They are created in the legal language as a type of language for special purposes and have intra- and exter-nal-text specificity. Legal texts, in spite of their genre variety, have a predominantly standard for-mat. Such types of legal text as court decisions and regulations, powers of attorney and contracts, wills, etc., have a specific construction plan, are divided into parts in a certain way and are drawn up graphically. Discursive analysis is considered as the most acceptable method of studying and teaching a foreign language of law.
A didactic model providing plurilingual training in multidisciplinary university
Authors: Shostak Ekaterina V.
Published: February 2021

Current trends in higher education suggest a gradual transition from a monolingual education system to a multilingual one. Nowadays, there is a need for professionals who speak English as well as other foreign languages and are able to cooperate with representatives of other cultures to find better solutions to industrial tasks. The research aims at elaborating a didactic model for the development of plurilingual competence among students of a multidisciplinary university. Research methods: literature analysis in the field of psychological studies and didactics, modeling, observation, pedagogical experiment. The configuration of the plurilingual competence structure is determined by introducing two sub-competences (professionally-oriented linguistic competence in English and common linguistic competence in the second foreign language – Spanish). The model structure with detailed characteristics of the component composition is described in detail. Methodological component contains the following approaches (competence, cognitive, interdisciplinary and activity theory based approaches) and didactic principles (of integration, basic learning strategies, flexible skills content organization, situational afferentation and reverse afferentation principles, homogeneous skills reduced interference principle, iteration and language structure based organization principle). Content component represented with a further description of the procedural and content aspects. An iteration and language structure based system of exercises has been developed. A general diagnostic framework for competence assessment and measurement has been introduced. The relationships between the components of the model are indicated. Conclusions are made about the applicability of the model in the environment of a multidisciplinary university.
Pedagogical conditions for teaching foreign language intercultural interaction of students based on the case method
Authors: Danilin Roman A.
Published: February 2021

The work is devoted to identifying and substantiating the list of pedagogical conditions for teaching foreign language intercultural interaction of students based on the case method. At the present stage, the case method is one of the modern methods of problem learning, based on the students’ analysis of specific situations. The case method can be used in the development of the skills of foreign language intercultural interaction of students. However, in order to achieve the ef-fectiveness of the proposed teaching methods, it is necessary to identify and substantiate a number of pedagogical conditions. Based on the analysis of pedagogical and methods literature on the use of distance and information and communication technologies in foreign language teaching, as well as methods and approaches to teaching foreign language intercultural interaction of students, a list of such conditions is proposed. There are four of them: a) students’ proficiency in a foreign language at the B1 level and above; b) the ability and readiness of a foreign language teacher to draw up cases aimed at developing the skills of intercultural interaction; c) the ability and readiness of students for collective interaction in the process of completing cases; d) sequential execution of the stages of the cases. The work provides a detailed description of each of the pedagogical conditions.
Teaching Turkic-speaking school students the morphemic structure of the word in the Russian language classes: ethno-cognitive approach
Authors: Zheleznyakova Elena A.
Published: February 2021

In a modern Russian school, together with Russian-speaking school students, children of migrants study, for most of whom are native Turkic languages. For foreigners, traditional lessons should be supplemented with corrective lessons in Russian as a non-native language, the effectiveness of which will be high provided that an ethno-cognitive approach to teaching is followed. Learning the morphemic structure of a word based on an ethno-cognitive approach is the subject of this study. The aim is to develop methodic recommendations based on the analysis of the features of the morphemic structure of Turkic words, to identify possible difficulties in mastering the morphemic structure of the Russian word by Turkic-speaking students, and to highlight methods and techniques based on the principles of consciousness and the development of students’ cognitive abilities. Two main difficulties in the field of the morphemic word structure for foreign children are highlighted: Russian inflection and morphological ways of word formation: prefix and prefix-suffix. When working with these topics, the teacher should develop students’ ability to think analytically, comparing and identifying the essential features of a linguistic phenomenon, make assumptions and find confirmation for them. Mastering inflection will be more effective if you group words thematically, work according to ready-made patterns and models of inflection, increase the number of tasks “for substitution” and “for replacement”. The following stages of work on concepts are substantiated: analysis of linguistic material and highlighting the main fea-tures of a concept; generalization of signs, establishing a connection between them and introducing the desired term; concretization of concepts based on new linguistic material.
Optimasi Biaya Perawatan Sistem dengan Faktor Diskon
Authors: Ayuriza Desyandi , Suyono Suyono , Hermin Fariani
Published: February 2021

AbstrakKegiatan perawatan dapat meminimalkan biaya atau kerugian yang ditimbulkan, apabila terdapat kerusakan pada suatu sistem. Biaya total perawatan bergantung pada jumlah dari tindakan perawatan preventif dan korektif yang dilakukan selama interval waktu tertentu. Skripsi ini membahas biaya total perawatan sistem dari komponen dalam waktu yang terbatas. Strategi penggantian usia komponen diasumsikan sebagai kerusakan komponen yang mengikuti sebuah proses gamma. Asumsikan faktor diskon yang perlu dimasukkan ke dalam perhitungan untuk mempersiapkan biaya yang diperlukan untuk biaya perawatan komponen pada interval waktu [0,t], maka akan menghasilkan waktu yang optimal antara perawatan preventif yang dilakukan secara berurutan untuk meminimalkan nilai ekspektasi dari biaya total perawatan. Sebuah contoh numerik dibahas pada bagian akhir skripsi ini untuk mengilustrasikan hasil yang telah diperoleh.

Kata kunci: strategi penggantian usia, proses Gamma, pendiskonan, proses Renewal, transformasi Laplace.
Characteristics of the Herd Immunity to SARS-CoV-2 in Residents of the Saratov Region under COVID-19 Epidemic
Authors: Popova A. Yu. , Ezhlova E. B. , Mel’nikova A. A. , Kutyrev V. V. , Kozhanova O. I. , Cherkasskaya T. S. , Lyalina V. I. , Smirnov V. S. , Bugorkova S. A. , Portenko S. A. , Naydenova E. V. , Shcherbakova S. A. , Lomonosova V. I. , Totolyan A. A.
Published: February 2021

The global community is experiencing one of the largest infectious disease outbreaks in the 21st century. In the Saratov Region, the first case of new coronavirus infection was confirmed on March 19, 2020.The maximum increase in cases was noted between May 15 and June 30, during that time the total number of infected people in the region increased from 1526 to 6444. Since July 2020, a stable incidence level of new coronavirus infection has been observed in the Saratov Region, without a steady decline.

The aim of the study was to assess the status of population immunity to the SARS-CoV-2 virus among residents of Saratov and the Saratov Region under the COVID-19 epidemic.

Materials and methods. In the period from June 23 to July 26, 2020, a serological study of blood samples from 3372 volunteers of different age groups was conducted. The content of antibodies to SARS-CoV-2 was determined by ELISA using a set of reagents “ELISA anti-SARS-CoV-2 IgG” produced by the State Scientific Center of Applied Microbiology and Biotechnology of the Rospotrebnadzor (Russia).

Results and discussion. In general, the incidence of COVID-19 in the Saratov Region is taking place against the background of moderate seroprevalence to the SARS-CoV-2 virus, accompanied by a high incidence of non-apparent (asymptomatic) forms of the infectious process. The absence of clinical symptoms of the disease, in the context of the limited use of methods for determining the RNA of the SARS-CoV-2 virus in PCR (11 % of the region’s population) makes it difficult to assess the real spread of the virus in the population and to establish the timing of the formation of persistent herd immunity. A low rate of antibody response among individuals with a positive result of PCR analysis, as well as among volunteers who had an infection in May, June 2020, indicates a weak formation of the immune response, or the prevalence of individuals reacting mainly by activating the cellular link of the immune system in the population. The obtained results, although they need to be explained in a number of respects, can be applied to the organization of preventive measures, including vaccination, in the region.
Assessment of Population Immunity to SARS-CoV-2 Virus in the Rostov Region
Authors: Popova A. Yu. , Ezhlova E. B. , Mel’nikova A. A. , Noskov A. K. , Kovalev E. V. , Karpushchenko G. V. , Lyalina L. V. , Smirnov V. S. , Chemisova O. S. , Trishina A. V. , Bereznyak E. A. , Volovikova S. V. , Stenina S. I. , Yanovich E. G. , Meloyan M. G. , Asmolova N. Yu. , Usova A. A. , Slis’ S. S. , Totolyan A. A.
Published: February 2021

By August 2020, more than 850000 cases of new coronavirus infection (COVID-19) caused by SARSCoV-2 were confirmed in the Russian Federation, with the Rostov Region as one of the ten most affected regions in Russia. The spread of the disease is largely determined by the state of population immunity in a certain area. Our research focuses on specific humoral immune response and estimates the level of herd immunity to SARS-CoV-2 virus among the population of the Rostov Region.

Materials and methods. The study involved 3,048 people; the volunteers participating in the study were divided into seven age groups. The content of antibodies to SARS-CoV-2 was determined applying ELISA using a kit for the analysis of human serum or blood plasma for the presence of specific IgG to the nucleocapsid of the SARS-CoV-2 virus, manufactured by the State Scientific Center of Applied Microbiology and Biotechnology (Obolensk) in accordance with the instructions for use.

Results and discussion. The assessment of seroprevalence to SARS-CoV-2 in the Rostov Region showed that the proportion of people positive for IgG to the new coronavirus was 16.5 %, the range of seropositive individuals in the general population was between 13.9 % and 19.1 % (p<0.05). There were no significant gender differences in the degree of seroprevalence with a positive result registered in 16.6 % of women and 16.5 % of men. A high level of humoral immunity to SARS-CoV-2 was established in individuals aged 1–17 against the background of low incidence rates, which may indicate the dominance of asymptomatic forms of the disease in this age group. The highest level of seropositivity was found in preschool children (33.6 %), students (29.3 %), employees (17.3 %), and education professionals (15.3 %).
Preparation of Class Y Immunoglobulins that Neutralize the Marburg Virus
Authors: Polezhaeva O. A. , Zybkina A. V. , Zaikovskaya A. V. , P’yankov O. V. , P’yankov S. A. , Semenova A. V. , Semenova G. V. , Shcherbakov D. N.
Published: February 2021

The aim was to study the possibility of inducing Marburg-neutralizing chicken antibodies (MARV) using various immunogens.

Materials and methods. Recombinant vaccinia virus expressing the surface glycoprotein (GP) transgene MARV of Musoke strain and pseudovirus particles exhibiting GP of three strains of MARV – Popp, Musoke and DRC2000 based on lentivirus and recombinant strain of vesicular stomatitis virus (VSV) were used as immunogens. Two groups of birds were involved in the study. Chickens were immunized 9 times: first time they were injected with the recombinant vaccinia virus, and then 8 times – with pseudovirus particles (based on lentivirus and a recombinant strain of the vesicular stomatitis virus). The accumulation of specific antibodies was evaluated by enzyme-linked immunosorbent assay (ELISA). We used recombinant VSV exhibiting GP MARV, and natural MARV strain Popp for the analysis of accumulation of neutralizing antibodies.

Results and discussion. We have developed an effective immunization schedule for chickens with three recombinant constructs presenting GP MARV, which results in the induction of chicken IgY antibodies against Marburg virus with a titer in ELISA from 1:100 to 1:1 million. The obtained IgY neutralize MARV pseudoviruses (Popp, DRC2000, Musoke) at a dilution of 1/256 to 1/1024 and the natural MARV virus of the Popp strain at a dilution of 1/8. More stable results were demonstrated by immunization using Freund’s incomplete adjuvant.
Mobile Complexes of the Specialized Anti-Epidemic Teams (SAET) of the Rospotrebnadzor as an Effective Tool in the Implementation of Measures to Counter New Coronavirus Infection COVID-19
Authors: Popova A. Yu. , Ezhlova E. B. , Demina Yu. V. , Kulichenko A. N. , Maletskaya O. V. , Ryazanova A. G. , Kuznetsova I. V. , Gnusareva O. A. , Mikhailova M. E. , Siritsa Yu. V. , Manin E. A. , Portenko S. A. , Krasovskaya T. Yu. , Kuklev V. E. , Kazakova E. S. , Danilevskaya M. M. , Safonova M. V. , Tel’nova N. V. , Ivanova S. M. , Lopatin A. A.
Published: February 2021

The mobile complexes of the specialized anti-epidemic teams (SAET) of the Rospotrebnadzor (mounted on the platform of auto chassis) have been actively involved in implementation of operational measures to counter COVID‑19 in the Russian Federation, aimed at management and conducting of diagnostic studies. Analysis of the activities of mobile SAET in Moscow and Makhachkala made it possible to formulate the basic principles of organizing their work in the most difficult period of negative development of the situation, increasing incidence and insufficient readiness of laboratory bases for mass research: tactics of advance actions, flexibility in using the potential of SAET mobile complexes, monitoring over the implementation of anti-contamination measures at all stages of PCR analysis and the development of a consultative and methodological (training) aspects of activities of the team specialists. The use of mobile SAETs of the Rospotrebnadzor once again demonstrated their significance as a universal tool to counter epidemics of infectious diseases.
Revisión de bases de datos existentes y relevantes en el fraude y autenticidad alimentarias
Authors: Álvarez B. M. , Pascual M. , Rusu A. , Bogason S. G.
Published: February 2021

El fraude y la autenticidad alimentaria es un problema global que va en aumento y afecta a todas las etapas de la cadena alimentaria. Los consumidores demandan que los alimentos cumplan con las especificaciones que se indican en el etiquetado y las autoridades tienen el papel de establecer medidas para garantizar que éstos sean seguros. Desafortunadamente, debido a la gran complejidad para detectar el fraude alimentario, muchos casos pasan desapercibidos provocando que se mantengan dentro de la cadena de suministro de alimentos hasta llegar al consumidor final. A pesar de que los principios de las buenas prácticas en la fabricación alimentaria deben garantizar que los productos fabricados cumplan con las especificaciones de calidad marcadas por los organismos de salud, las empresas alimentarias necesitan tener acceso a herramientas de consulta fiables para asegurar la procedencia y seguridad de los productos que reciben. Este estudio recoge información relacionada con el fraude y la autenticidad alimentaria, y evalúa el acceso que tiene la industria y en particular, las pequeñas y medianas empresas (PYMES), a la información contenida en bases de datos on-line. Se han establecido varias categorias, y todas las bases de datos contenidas en cada una de ellas, han sido analizadas y seleccionadas según su estructura y relevancia para los usuarios. Todas las bases de datos incluidas han sido extraidas de internet y están desarrolladas tanto por organismos públicos, como privados, por lo que están destinadas a llegar a un gran número de usuarios. También se ha realizado un estudio general de bases de datos relevantes que han sido desarrolladas en proyectos europeos.
Out-of-phase cyclical sediment supply: A potential causal mechanism for generating stratigraphic asymmetry and explaining sequence stratigraphic spatial variability
Authors: Ainsworth R. Bruce , Vonk Adam J. , Wellington Paul , Paumard Victorien
Published: February 2021

Although acknowledged to be a simplification, the rate of sediment supply is usually assumed to be constant in sequence stratigraphic interpretations of clastic shelf systems. The simplified assumption taken in this work is that sediment supply can be represented by sine curves linked to climate changes driven by Milankovitch cycles. Three orders of sediment supply sine curves (amplitude and frequency scaled to order) are convolved with three orders of Milankovitch-forced eustatic sea-level sine curves and a constant rate of subsidence to generate curves for the ratio of rate of accommodation development to rate of sediment supply (δ A /δ S ). The relative-sea-level curve is then held constant whilst sediment supply is systematically changed from being constant to being cyclical across the three orders of Milankovitch frequencies and being in-phase, and out-of-phase with the eustatic cycles by 90°, 180°, and 270°. For each scenario, stratal architecture is then represented for sixty consecutive parasequences (fifth-order, regressive–transgressive shelf transit cycles) by converting the δ A /δ S curves into pseudo thickness / sandstone fraction plots (TSF plots). Constant sediment supply, in-phase sediment supply, and 180°-out-of-phase sediment supply produce symmetrical stratal geometries with equal periods of progradation, aggradation, and retrogradation. When sediment-supply cycles are 90°-out-of-phase (supply peak occurs later than sea-level peak), stratal geometries are asymmetrical with progradational architectures being dominant. When sediment-supply cycles are 270°-out-of-phase (supply peak occurs earlier than sea-level peak), stratal geometries are also asymmetrical but retrogradational architectures are dominant. These patterns are reproduced at all three orders of stratigraphic hierarchy (parasequence, sequence, and composite sequence). Comparison of these synthetic stratal geometries to real-world stratal geometries from Triassic to Neogene rocks across both the fifth-order (parasequence) and fourth-order (sequence) of stratal hierarchies suggests a consistently occurring asymmetrical, progradation-dominant motif. This indicates that 90°-out-of-phase sediment supply (supply peak occurs later than sea-level peak) may be a common occurrence through geological time. The work also corroborates the findings of earlier workers and suggests that sequence stratigraphic surfaces can change nature along depositional strike due to out-of-phase sediment supply and can thus also be diachronous. This work conceptually illustrates that Milankovitch climate-change-induced sinusoidal-sediment-supply cycles, out-of-phase with sinusoidal eustatic-sea-level cycles, may produce commonly observed asymmetrical stratal architectures and should be considered when invoking causal mechanisms for stratal architectures on clastic shelves.
Fringe or background: Characterizing deep-water mudstones beyond the basin-floor fan sandstone pinchout
Authors: Boulesteix Kévin , Poyatos-Moré Miquel , Hodgson David M. , Flint Stephen S. , Taylor Kevin G.
Published: February 2021

Mud dominates volumetrically the fraction of sediment delivered and deposited in deep-water environments, and mudstone is a major component of basin-floor successions. However, studies of basin-floor deposits have mainly focused on their proximal sandstone-prone part. A consequent bias therefore remains in the understanding of depositional processes and stratigraphic architecture in mudstone-prone distal settings beyond the sandstone pinchouts of basin-floor fans. This study uses macroscopic and microscopic descriptions of over 500 m of continuous cores from research boreholes from the Permian Skoorsteenberg Formation of the Karoo Basin, South Africa, to document the sedimentology, stratigraphy, and ichnology of a distal mudstone-prone basin-floor succession. Very thin- to thin-bedded mudstones, deposited by low-density turbidity currents, stack to form bedsets bounded by thin packages (< 0.7 m thick) of background mudstones. Genetically related bedsets stack to form bedset packages, which are bounded by thicker (> 0.7 m thick) background mudstones. Stratigraphic correlation between cores suggests that bedsets represent the distal fringes of submarine fan lobe elements and/or lobes, and bedset packages represent the distal fringes of lobe complexes and/or lobe complex sets. The internal stacking pattern of bedsets and bedset packages is highly variable vertically and laterally, which records dominantly autogenic processes (e.g., compensational stacking, avulsion of feeder channels). The background mudstones are characterized by remnant tractional structures and outsize particles, and are interpreted as deposited from low-density turbidity currents and debris flows before intense biogenic reworking. These observations challenge the idea that mud accumulates only from hemipelagic suspension fallout in distal basin-floor environments. Thin background mudstones separating bedsets (< 0.7 m thick) are interpreted to mainly represent autogenically driven lobe abandonment due to up-dip channel avulsion. The thicker background mudstones separating bedset packages (> 0.7 m thick) are interpreted to dominantly mark allogenically driven regional decrease of sand supply to the basin floor. The recognition of sandstone-prone basin-floor fans passing into genetically linked distal fringe mudstones suggests that submarine lobes are at least ∼ 20 km longer than previously estimated. This study provides sedimentological, stratigraphic, and ichnological criteria to differentiate mudstones deposited in different sub-environments in distal deep-water basin-floor settings, with implications for the accurate characterization of basin-floor fan architecture, and their use as archives of paleoenvironmental change.
Decision Supporting System For Malang City Baseball and Softball Athletes Selection Using The Vikor Method
Authors: Amalia Eka Larasati , Ikawati Deasy Sandhya Elya , Laksana Muhammad Arya Puja
Published: February 2021

Decision support system is a computer-based system that is used to solve problems by semi-structured and unstructured conditions. In this case, the best solution can be found from certain criteria and provided alternatives and is easy to use by users. In this study, researchers designed and built a website-based decision support system to select athletes in PERBASASI Malang with the provided test criteria, namely the hit test, catch test, throw test, and run test. The purpose of this study was to provide recommendations for participants who passed the selection based on test scores that have been processed using the VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) method. From the results of calculations, the use of the VIKOR method for this case study produced an accuracy value of 90.90%, a precision value of 93.33%, and a recall value of 93.33%. In addition, the VIKOR sensitivity test showed a consistent ranking of the calculation of the value with veto (value of v less than 0.5), by consensus (value of v is 0.5), and voting by majority rule (value of v more than 0.5). User testing that was applied by using each level of the existing account, i.e. administrator account level, selection account level, and members account level conducted on this information system concluded that the system that was built was running smoothly and was easy to use.